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2022 ◽  
Vol 12 ◽  
Author(s):  
Kadi J. Horn ◽  
Alexander C. Jaberi Vivar ◽  
Vera Arenas ◽  
Sameer Andani ◽  
Edward N. Janoff ◽  
...  

The stability and composition of the airway microbiome is an important determinant of respiratory health. Some airway bacteria are considered to be beneficial due to their potential to impede the acquisition and persistence of opportunistic bacterial pathogens such as Streptococcus pneumoniae. Among such organisms, the presence of Corynebacterium species correlates with reduced S. pneumoniae in both adults and children, in whom Corynebacterium abundance is predictive of S. pneumoniae infection risk. Previously, Corynebacterium accolens was shown to express a lipase which cleaves host lipids, resulting in the production of fatty acids that inhibit growth of S. pneumoniae in vitro. However, it was unclear whether this mechanism contributes to Corynebacterium-S. pneumoniae interactions in vivo. To address this question, we developed a mouse model for Corynebacterium colonization in which colonization with either C. accolens or another species, Corynebacterium amycolatum, significantly reduced S. pneumoniae acquisition in the upper airway and infection in the lung. Moreover, the lungs of co-infected mice had reduced pro-inflammatory cytokines and inflammatory myeloid cells, indicating resolution of infection-associated inflammation. The inhibitory effect of C. accolens on S. pneumoniae in vivo was mediated by lipase-dependent and independent effects, indicating that both this and other bacterial factors contribute to Corynebacterium-mediated protection in the airway. We also identified a previously uncharacterized bacterial lipase in C. amycolatum that is required for inhibition of S. pneumoniae growth in vitro. Together, these findings demonstrate the protective potential of airway Corynebacterium species and establish a new model for investigating the impact of commensal microbiota, such as Corynebacterium, on maintaining respiratory health.


Author(s):  
Ryan J. Scalsky ◽  
Yi-Ju Chen ◽  
Zhekang Ying ◽  
James A. Perry ◽  
Charles C. Hong

COVID-19 has caused a global pandemic with considerable impact. Studies have examined the influence of socioeconomic status and air pollution on COVID-19 risk but in low detail. This study seeks to further elucidate the nuances of socioeconomic status, as defined by the Index of Multiple Deprivation (IMD), air pollution, and their relationship. We examined the effect of IMD and air pollution on the likelihood of testing positive for SARS-CoV-2 among 66,732 UKB participants tested for SARS-CoV-2 from 16 March 2020 through 16 March 2021. Logistic regression was performed controlling for age, sex, ancestry and IMD or air pollution in the respective models. IMD and its sub-scores were significantly associated with increased risk of testing positive for SARS-CoV-2. All particulate matter less than 2.5 μm (PM2.5), nitrogen oxide (NOx), and nitrogen dioxide (NO2) levels were associated with increased likelihood of testing positive for SARS-CoV-2. Measures of green space and natural environment around participants’ homes were associated with reduced likelihood of SARS-CoV-2. Socioeconomic status and air pollution have independent effects on the risk of testing positive for SARS-CoV-2. Green space and natural environment space in the proximity of people’s homes may mediate the effect of air pollution on the risk of testing positive for SARS-CoV-2.


2021 ◽  
Author(s):  
Adi Zheng ◽  
Gilles Dubuis ◽  
Maria Georgieva ◽  
Carla Susana Mendes Ferreira ◽  
Marc Serulla ◽  
...  

High-density lipoproteins (HDLs) prevent cell death induced by a variety of cytotoxic drugs. The underlying mechanisms are however still poorly understood. Here we present evidence that HDLs efficiently protect cells against thapsigargin (TG), a sarco/ endoplasmic reticulum (ER) Ca2+-ATPase (SERCA) inhibitor, by extracting the drug from cells. Drug efflux could also be triggered to some extent by low-density lipoproteins and serum. HDLs did not reverse the non-lethal mild ER stress response induced by low TG concentrations or by SERCA knock-down but HDLs inhibited the toxic SERCA-independent effects mediated by high TG concentrations. HDLs could extract other lipophilic compounds, but not hydrophilic substances This work shows that HDLs utilize their capacity of loading themselves with lipophilic compounds, akin to their ability to extract cellular cholesterol, to reduce the cell content of hydrophobic drugs. This can be beneficial if lipophilic xenobiotics are toxic but may be detrimental to the therapeutic benefit of lipophilic drugs such as glibenclamide.


2021 ◽  
Author(s):  
Philipp Kuhnke ◽  
Curtiss A. Chapman ◽  
Vincent K.M. Cheung ◽  
Sabrina Turker ◽  
Astrid Graessner ◽  
...  

Abstract Semantic knowledge is central to human cognition. The angular gyrus (AG) is widely considered a key brain region for semantic cognition. However, the role of the AG in semantic processing is controversial. Key controversies concern response polarity (activation vs. deactivation) and its relation to task difficulty, lateralization (left vs. right AG), and functional-anatomical subdivision (PGa vs. PGp subregions). Here, we combined the fMRI data of five studies on semantic processing (n = 172) and analyzed the response profiles from the same anatomical regions-of-interest for left and right PGa and PGp. We found that the AG was consistently deactivated during non-semantic conditions, whereas response polarity during semantic conditions was inconsistent. However, the AG consistently showed relative response differences between semantic and non-semantic conditions, and between different semantic conditions. A combined analysis across all studies revealed that AG responses could be best explained by independent effects of both task difficulty and semantic processing demand. Task difficulty effects were stronger in PGa than PGp, regardless of hemisphere. Semantic effects were stronger in left than right AG, regardless of subregion. These results suggest that the AG is independently engaged in both domain-general task-difficulty-related processes and domain-specific semantic processes. In semantic processing, we propose that left AG acts as a “multimodal convergence zone” that binds different semantic features associated with the same concept, enabling efficient access to task-relevant features.


2021 ◽  
Author(s):  
Philipp Kuhnke ◽  
Curtiss A. Chapman ◽  
Vincent K.M. Cheung ◽  
Sabrina Turker ◽  
Astrid Graessner ◽  
...  

Semantic knowledge is central to human cognition. The angular gyrus (AG) is widely considered a key brain region for semantic cognition. However, the role of the AG in semantic processing is controversial. Key controversies concern response polarity (activation vs. deactivation) and its relation to task difficulty, lateralization (left vs. right AG), and functional-anatomical subdivision (PGa vs. PGp subregions). Here, we combined the fMRI data of five studies on semantic processing (n = 172) and analyzed the response profiles from the same anatomical regions-of-interest for left and right PGa and PGp. We found that the AG was consistently deactivated during non-semantic conditions, whereas response polarity during semantic conditions was inconsistent. However, the AG consistently showed relative response differences between semantic and non-semantic conditions, and between different semantic conditions. A combined analysis across all studies revealed that AG responses could be best explained by independent effects of both task difficulty and semantic processing demand. Task difficulty effects were stronger in PGa than PGp, regardless of hemisphere. Semantic effects were stronger in left than right AG, regardless of subregion. These results suggest that the AG is independently engaged in both domain-general task-difficulty-related processes and domain-specific semantic processes. In semantic processing, we propose that left AG acts as a "multimodal convergence zone" that binds different semantic features associated with the same concept, enabling efficient access to task-relevant features.


2021 ◽  
Vol 15 ◽  
Author(s):  
Johanna Wind ◽  
Fabian Horst ◽  
Nikolas Rizzi ◽  
Alexander John ◽  
Tamara Kurti ◽  
...  

To date, most neurophysiological dance research has been conducted exclusively with female participants in observational studies (i.e., participants observe or imagine a dance choreography). In this regard, the sex-specific acute neurophysiological effect of physically executed dance can be considered a widely unexplored field of research. This study examines the acute impact of a modern jazz dance choreography on brain activity and functional connectivity using electroencephalography (EEG). In a within-subject design, 11 female and 11 male participants were examined under four test conditions: physically dancing the choreography with and without music and imagining the choreography with and without music. Prior to the EEG measurements, the participants acquired the choreography over 3 weeks with one session per week. Subsequently, the participants conducted all four test conditions in a randomized order on a single day, with the EEG measurements taken before and after each condition. Differences between the male and female participants were established in brain activity and functional connectivity analyses under the condition of imagined dance without music. No statistical differences between sexes were found in the other three conditions (physically executed dance with and without music as well as imagined dance with music). Physically dancing and music seem to have sex-independent effects on the human brain. However, thinking of dance without music seems to be rather sex-specific. The results point to a promising approach to decipher sex-specific differences in the use of dance or music. This approach could further be used to achieve a more group-specific or even more individualized and situationally adapted use of dance interventions, e.g., in the context of sports, physical education, or therapy. The extent to which the identified differences are due to culturally specific attitudes in the sex-specific contact with dance and music needs to be clarified in future research.


2021 ◽  
Author(s):  
Mohammad Bagher Hassanpouraghdam ◽  
Lamia Vojodi Mehrabani ◽  
Mehdi Kheiri ◽  
Antonios Chrysargyris ◽  
Nikolaos Tzortzakis

Abstract The effects of NaCl salinity stress and foliar application of KNO3, glucose and Dobogen were tested on Tanacetum balsamita. The results showed the significant interaction effects of salinity and foliar sprays on chlorophyll a, K+, Na+, Mg2+, Fe2+, Zn2+, Mn2+ and Si content, K/Na ratio and total phenolic and flavonoid contents. The highest phenolic content was acquired with 100 mM salinity and foliar spray of Dobogen and glucose, 50 mM NaCl × KNO3 application and 50 mM salinity× nonfoliar application. The highest K/Na ratio was observed in control plants and controls × KNO3 and/or Dobogen application. The greatest Si content was recorded with controls × Dobogen and KNO3 applications and no saline × no foliar control plants. Malondialdehyde, flavonoid and proline contents as well as catalase activity were influenced by the independent effects of treatments. Chlorophyll b and superoxide dismutase were affected by salinity. Total soluble solids and Ca2+ were influenced by foliar applications. Malondialdehyde and proline were the highest at 150 mM salinity. Salinity adversely affected the physiological responses of costmary. However, foliar treatments partially ameliorated the salinity effect, and the results would be advisable to the extension section and pioneer farmers.


2021 ◽  
Author(s):  
Mohammad Bagher Hassanpouraghdam ◽  
Lamia Vojodi Mehrabani ◽  
Zahra Masoumpour ◽  
Amir Soltanbeigi ◽  
Dilfuza Egamberdieva

Abstract Background: The secondary metabolites from savory species are widely used in food and pharmaceutical industries. Salt accumulation in the growing medium adversely affects the growth and yield of plants. The hyper-availability of Na+ and Cl- triggers nutrient imbalances, leading to secondary ionic stress. Under salinity exposure, the reactive oxygen species (ROS) over-generation drives oxidative stress in cells. Moreover, when facing environmental stress factors; the availability of essential nutrients and especially micro-elements strongly declines. Foliar application of micro-nutrients principally as nano-form is a promising strategy in meeting the nutritional demands of plants under stress environments with progressive nutrient shortages. Nano-materials and the supply of nutrients as foliar treatments meliorate the growth, biochemical reactions, and nutrient use efficiency of plants under salinity. The idea with the present experiment was to assay the effects of nano-Fe (magnetized-Fe) and selenium foliar application on the growth and some physiological responses of two Satureja species under saline-sodic conditions.Results: When studying the foliar application of Se and nano-Fe (0 and 3 mg L-1) on Satureja mutica and Satureia spicigera via two separate experiments, under normal no-saline conditions; the highest catalase activity was recorded in magnetized-Fe treated plants in both species. Independent effects of foliar application and plant species influenced total phenolics and Mg content of leaves. Foliar sprays reduced MDA content in plant tissue. In the second experiment, foliar applications were evaluated under salinity conditions. No-saline × Se and magnetized-Fe treated plants attained the highest data for aerial parts biomass in S. spicigera.Conclusion: The results demonstrated that salinity adversely influenced the growth and physiological responses, nevertheless, foliar spray with Se and magnetized-Fe partially ameliorated the salinity depression on Satureja species.


Author(s):  
Cheng Yong Tan ◽  
Clive Dimmock ◽  
Allan Walker

The present study aims to generate broad insights from the large corpus of literature on the associations between a comprehensive range of school leadership practices and student outcomes in different school contexts. Three-level meta-analysis of 493 independent effects from 108 studies published since 2000 showed that the mean effect size was small at r  = 0.14. Effect sizes for leadership practices ranged from r’s  = 0.10 to .26. Results underscored the importance of different types of leadership practices related to instructional management, enhancing teacher capacity, and engaging external stakeholders to improve student outcomes. School leadership practices were significantly associated with students’ academic achievement (in different subjects except science) and learning attitudes/processes but not attainment. Moderator analyses showed that school leadership effects were significant in studies using a school-level analysis but not in those using a lower-level of analysis. Additionally, school leadership effects were significant at different grade levels (G1–G6, G7–G12) and in research reported in different study types (articles, dissertations) and in different years (2000–2009, 2010–2018).


2021 ◽  
Vol 19 ◽  
Author(s):  
Lei Wang ◽  
Douglas F. Covey ◽  
Gustav Akk ◽  
Alex S. Evers

: Neurosteroids are endogenous modulators of GABAA receptors that mediate anxiety, pain, mood and arousal. The 3-hydroxyl epimers, allopregnanolone (3α-OH) and epi-allopregnanolone (3β-OH) are both prevalent in mammalian brain and produce opposite effects on GABAA receptor function, acting as positive and negative allosteric modulators respectively. This Perspective provides a model to explain the actions of 3α-OH and 3β-OH neurosteroids. The model is based on evidence that the neurosteroid epimers bind to an overlapping subset of specific sites on GABAA receptors, with their net functional effect on channel gating being the sum of their independent effects at each site.


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