The phenomenon of Förster (or fluorescence) resonance energy transfer (FRET) between two fluorescent proteins of different hues provides a robust foundation for the design and construction of ...biosensors for the detection of intracellular events. Accordingly, FRET-based biosensors for a variety of biologically relevant ions, molecules, and specific enzymatic activities, have now been developed and used to investigate numerous questions in cell biology. An emerging trend in the use of FRET-based biosensors is to apply them in combination with a second biosensor in order to achieve simultaneous imaging of multiple biochemical parameters in a single living cell. Here we discuss the particular technological challenges facing the use of FRET-based biosensors in multiparameter live cell fluorescence imaging and highlight recent efforts to overcome these challenges. In addition, we survey recent applications and provide an outlook on the future opportunities in this area.
Unpasteurized dairy products are known to occasionally harbor Listeria monocytogenes and have been implicated in recent listeriosis outbreaks and numerous sporadic cases of listeriosis. However, the ...diversity and virulence profiles of L. monocytogenes isolates recovered from these products have not been fully described. Here we report a genomic analysis of 121 L. monocytogenes isolates recovered from milk, milk filters, and milking equipment collected from bovine dairy farms in 19 states over a 12-year period. In a multi-virulence-locus sequence typing (MVLST) analysis, 59 Virulence Types (VT) were identified, of which 25% were Epidemic Clones I, II, V, VI, VII, VIII, IX, or X, and 31 were novel VT. In a multi-locus sequence typing (MLST) analysis, 60 Sequence Types (ST) of 56 Clonal Complexes (CC) were identified. Within lineage I, CC5 and CC1 were among the most abundant, and within lineage II, CC7 and CC37 were the most abundant. Multiple CCs previously associated with central nervous system and maternal-neonatal infections were identified. A genomic analysis identified variable distribution of virulence markers, Listeria pathogenicity islands (LIPI) -1, -3, and -4, and stress survival island-1 (SSI-1). Of these, 14 virulence markers, including LIPI-3 and -4 were more frequently detected in one lineage (I or II) than the other. LIPI-3 and LIPI-4 were identified in 68% and 28% of lineage I CCs, respectively. Results of this analysis indicate that there is a high level of genetic diversity among the L. monocytogenes present in bulk tank milk in the United States with some strains being more frequently detected than others, and some being similar to those that have been isolated from previous non-dairy related outbreaks. Results of this study also demonstrate significant number of strains isolated from dairy farms encode virulence markers associated with severe human disease.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Gene expression is known to be affected by interactions between local genetic variation and DNA accessibility, with the latter organized into three-dimensional chromatin structures. Analyses of these ...interactions have previously been limited, obscuring their regulatory context, and the extent to which they occur throughout the genome. Here, we undertake a genome-scale analysis of these interactions in a genetically diverse population to systematically identify global genetic-epigenetic interaction, and reveal constraints imposed by chromatin structure. We establish the extent and structure of genotype-by-epigenotype interaction using embryonic stem cells derived from Diversity Outbred mice. This mouse population segregates millions of variants from eight inbred founders, enabling precision genetic mapping with extensive genotypic and phenotypic diversity. With 176 samples profiled for genotype, gene expression, and open chromatin, we used regression modeling to infer genetic-epigenetic interactions on a genome-wide scale. Our results demonstrate that statistical interactions between genetic variants and chromatin accessibility are common throughout the genome. We found that these interactions occur within the local area of the affected gene, and that this locality corresponds to topologically associated domains (TADs). The likelihood of interaction was most strongly defined by the three-dimensional (3D) domain structure rather than linear DNA sequence. We show that stable 3D genome structure is an effective tool to guide searches for regulatory elements and, conversely, that regulatory elements in genetically diverse populations provide a means to infer 3D genome structure. We confirmed this finding with CTCF ChIP-seq that revealed strain-specific binding in the inbred founder mice. In stem cells, open chromatin participating in the most significant regression models demonstrated an enrichment for developmental genes and the TAD-forming CTCF-binding complex, providing an opportunity for statistical inference of shifting TAD boundaries operating during early development. These findings provide evidence that genetic and epigenetic factors operate within the context of 3D chromatin structure.
Adolescents' appearance-related concerns can provoke increasing emotional, social, and eating-related problems. The aims of this five-wave (2.5-year), multiple-informant longitudinal study were to ...(a) examine growth trajectories of appearance anxiety symptoms and appearance esteem, (b) identify whether trajectories differed by gender, and (c) examine several launching factors including parent-reported physical maturation, peer-rated physical appearance, body mass index, and appearance teasing by parents and peers. Participants were 387 adolescents (44% boys) aged 10 to 13 years at the first assessment. Steep growth in appearance anxiety symptoms was found for both girls and boys, but there was no average change in appearance esteem. Girls had more elevated appearance anxiety symptoms and lower appearance esteem than boys, girls' body mass index was associated with symptoms, and earlier physical maturation and teasing about appearance, alone and in combination, were associated with growth in appearance anxiety symptoms for girls and boys. Earlier maturing boys who were highly teased by parents, but even more so when teased by peers, were at utmost risk for elevated appearance anxiety symptoms and increasing symptoms over time. In contrast, all girls exhibited elevated or increasing appearance anxiety symptoms across time, with the exception of girls with the latest maturation who also reported little teasing about their appearance.
We review the research conducted in the past 15 years concerned with the role of friends and peers in adolescent body dissatisfaction. A number of friend and peer group characteristics have been ...associated with heightened body dissatisfaction both concurrently and longitudinally. Most widely studied and more consistently linked to body dissatisfaction are appearance teasing and perceived pressure from friends to be thin. Other interactions between friends and peers that communicate and strengthen appearance ideals and direct attention to appearance also have been associated with body dissatisfaction, including appearance‐related conversations, friends' modeling of dieting behavior, and perceptions of friends' appearance‐related attitudes. Finally, the research is critiqued, new directions considered, and strategies are proposed that could be implemented to reduce body dissatisfaction.
Theories of ethnic conflict predict that between-group inequality should be associated with a greater likelihood of violent conflict, but empirical results have been mixed. One reason might be that ...different types of inequalities have opposing effects on the likelihood of conflict. In this article, we posit that educational inequalities are likely to incentivize collective action by inducing grievances, while economic and demographic inequalities may actually dis-incentivize collective action by limiting opportunities for disadvantaged groups to engage in rebellion. We test these hypotheses on a new ethnic dyad database, incorporating 1,548 dyads formed by 290 ethnic groups living in 29 Sub-Saharan African countries. The analysis reveals that educational inequalities are indeed positively associated with conflict incidence, while this is not the case for economic and demographic inequalities. The association between educational inequality and conflict is stronger if the groups are wealthier. A higher joint educational level of the groups is associated with less conflict, particularly under more autocratic regimes. These findings demonstrate that to better understand the relationship between inequality and conflict, it is important to disaggregate the effects of inequalities according to the underlying mechanisms and the political context with which they are associated.
Escherichia coli ST117 is a pandemic extraintestinal pathogenic E. coli (ExPEC) causing significant morbidity globally. Poultry are a known reservoir of this pathogen, but the characteristics of ...ST117 strains from other animal sources have not been adequately investigated. Here we characterize the genomes of 36 ST117 strains recovered primarily from preweaned dairy calves, but also from older postweaned calves and lactating cows, in the context of other bovine-associated strains and strains from poultry, swine, and humans. Results of this study demonstrate that bovine-associated ST117 genomes encode virulence factors (VFs) known to be involved in extraintestinal infections, but also occasionally encode the Shiga toxin, a virulence factor (VF) involved in severe gastrointestinal infections and more frequently identified in E. coli from ruminants than other animals. Bovine-associated ST117 genomes were also more likely to encode afa-VIII (adhesins), pap (P-fimbriae), cdt (cytolethal distending toxin), and stx (Shiga toxins) than were poultry and swine-associated genomes. All of the ST117 genomes were grouped into seven virulence clusters, with bovine-associated genomes grouping into Clusters 1, 2, 4, 5, but not 3, 6, or 7. Major differences in the presence of virulence factors between clusters were observed as well. Antimicrobial resistance genes were detected in 112 of 122 (91%) bovine-associated genomes, with 103 of these being multidrug-resistant (MDR). Inclusion of genomes that differed from ST117 by one multi-locus sequence type (MLST) allele identified 31 STs, four of these among the bovine-associated genomes. These non-ST117 genomes clustered with the ST117 genomes suggesting that they may cause similar disease as ST117. Results of this study identify cattle as a reservoir of ST117 strains, some of which are highly similar to those isolated from other food animals and some of which have unique bovine-specific characteristics.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The objectives were to analyze treatment, clinical outcomes, and predictors of mortality in hospitalized patients with Acinetobacter baumannii infection. This was a retrospective cohort study of ...inpatients with A. baumannii cultures and treatment from 2010 to 2019. Patients who died during admission were compared to those who survived, to identify predictors of inpatient mortality, using multivariable unconditional logistic regression models. We identified 4,599 inpatients with A. baumannii infection; 13.6% died during admission. Fluoroquinolones (26.8%), piperacillin-tazobactam (24%), and carbapenems (15.6%) were used for treatment. Tigecycline (3%) and polymyxins (3.7%) were not used often. Predictors of inpatient mortality included current acute respiratory failure (adjusted odds ratio aOR 3.94), shock (aOR 3.05), and acute renal failure (aOR 2.01); blood (aOR 1.94) and respiratory (aOR 1.64) infectious source; multidrug-resistant A. baumannii (MDRAB) infection (aOR 1.66); liver disease (aOR 2.15); and inadequate initial treatment (aOR 1.30). Inpatient mortality was higher in those with MDRAB versus non-MDRAB (aOR 1.61) and in those with CRAB versus non-CRAB infection (aOR 1.68). Length of stay >10 days was higher among those with MDRAB versus non-MDRAB (aOR 1.25) and in those with CRAB versus non-CRAB infection (aOR 1.31). In our national cohort of inpatients with A. baumannii infection, clinical outcomes were worse among those with MDRAB and/or CRAB infection. Predictors of inpatient mortality included several current conditions associated with severity, infectious source, underlying illness, and inappropriate treatment. Our study may assist health care providers in the early identification of admitted patients with A. baumannii infection who are at higher risk of death.
The aim of the present study was to examine whether parents' reported use of controlling feeding practices (restrictive feeding and pressure to eat) change over 6 months, and whether parents' ...concerns about their own weight and shape are prospectively associated with increasing use of controlling feeding practices. Participants were 48 Australian parents (92% female; Mage = 37.8 years) who completed questionnaires twice, with a 6-month time lag, regarding a target child aged 7.6 years on average (52% female). Results revealed that, in general, parental feeding practices and body dissatisfaction showed little change over 6 months. As expected, parental body dissatisfaction predicted increased use over time of restrictive feeding practices for the purpose of managing child weight, but (unexpectedly) not restrictive feeding for child health or pressure to eat. The findings provide key evidence that parents who use higher levels of controlling feeding practices are likely to continue to do so over time, and that parental body dissatisfaction poses a small but significant risk for parents' increasing use of restrictive feeding for management of child weight. The present findings support suggestions that the connection between parent body dissatisfaction and maladaptive feeding practices play a role in the intergenerational transmission of body image and eating pathology.
•Pressure to eat and restrictive feeding showed rank order consistency over 6 months.•No mean-level differences over time for pressure to eat and restriction for health•Mean-level differences (i.e., decline) over time found for restriction for weight•Parent body dissatisfaction predicted greater restrictive feeding for child weight.•Parent body dissatisfaction was not related to pressure or restriction for health.
We describe a method that adds long-read sequencing to a mix of technologies used to assemble a highly complex cattle rumen microbial community, and provide a comparison to short read-based methods. ...Long-read alignments and Hi-C linkage between contigs support the identification of 188 novel virus-host associations and the determination of phage life cycle states in the rumen microbial community. The long-read assembly also identifies 94 antimicrobial resistance genes, compared to only seven alleles in the short-read assembly. We demonstrate novel techniques that work synergistically to improve characterization of biological features in a highly complex rumen microbial community.
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