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The importance of targeting persister cells in antibiotic therapies is becoming more evident, as these antibiotic-tolerant cells underlie relapsing infections and resistance development. Here, we studied persistence in a clinically relevant pathogen, Pseudomonas aeruginosa. Clinicians are increasingly confronted with the limitations of antibiotics to clear bacterial infections in patients. It has long been assumed that only antibiotic resistance plays a pivotal role in this phenomenon. Indeed, the worldwide emergence of antibiotic resistance is considered one of the major health threats of the 21st century. However, the presence of persister cells also has a significant influence on treatment outcomes. These antibiotic-tolerant cells are present in every bacterial population and are the result of the phenotypic switching of normal, antibiotic-sensitive cells. Persister cells complicate current antibiotic therapies and contribute to the development of resistance. In the past, extensive research has been performed to investigate persistence in laboratory settings; however, antibiotic tolerance under conditions that mimic the clinical setting remain poorly understood. In this study, we optimized a mouse model for lung infections with the opportunistic pathogen Pseudomonas aeruginosa. In this model, mice are intratracheally infected with P. aeruginosa embedded in seaweed alginate beads and subsequently treated with tobramycin via nasal droplets. A diverse panel of 18 P. aeruginosa strains originating from environmental, human, and animal clinical sources was selected to assess survival in the animal model. Survival levels were positively correlated with the survival levels determined via time-kill assays, a common method to study persistence in the laboratory. We showed that survival levels are comparable and thus that the classical persister assays are indicative of antibiotic tolerance in a clinical setting. The optimized animal model also enables us to test potential antipersister therapies and study persistence in relevant settings.IMPORTANCE The importance of targeting persister cells in antibiotic therapies is becoming more evident, as these antibiotic-tolerant cells underlie relapsing infections and resistance development. Here, we studied persistence in a clinically relevant pathogen, Pseudomonas aeruginosa. It is one of the six ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, P. aeruginosa, and Enterobacter spp.), which are considered major health threats. P. aeruginosa is mostly known to cause chronic lung infections in cystic fibrosis patients. We mimicked these lung infections in a mouse model to study persistence under more clinical conditions. It was shown that the survival levels of natural P. aeruginosa isolates in this model are positively correlated with the survival levels measured in classical persistence assays in vitro. These results not only validate the use of our current techniques to study persistence but also open opportunities to study new persistence mechanisms or evaluate new antipersister strategies in vivo.

Climate change could be an existential threat to many crops. Drought and heat stress are becoming harder for cultivated crops. Cotton in Pakistan is grown under natural high temperature and low moisture, could be used as a source of heat and drought tolerance. Therefore, the study was conducted to morphological, physiological and molecular characterization of cotton genotypes under field conditions. A total of 25 cotton genotypes were selected from the gene pool of Pakistan based on tolerance to heat and drought stress. In field trail, the stress related traits like boll retention percentage, plant height, number of nodes and inter-nodal distance were recorded. In physiological assessment, traits such as photosynthesis rate, stomatal conductance, transpiration rate, leaf temperature, relative water content and excised leaf water loss were observed. At molecular level, a set of 19 important transcription factors, controlling drought/heat stress tolerance (HSPCB, GHSP26, HSFA2, HSP101, HSP3, DREB1A, DREB2A, TPS, GhNAC2, GbMYB5, GhWRKY41, GhMKK3, GhMPK17, GhMKK1, GhMPK2, APX1, HSC70, ANNAT8, and GhPP2A1) were analyzed from all genotypes. Data analyses depicted that boll retention percentage, photosynthesis, stomatal conductance, relative water content under the stress conditions were associated with the presence of important drought & heat TF/genes which depicts high genetic potential of Pakistani cotton varieties against abiotic stress. The variety MNH-886 appeared in medium plant height, high boll retention percentage, high relative water content, photosynthesis rate, stomatal conductance, transpiration rate and with maximum number transcription factors under study. The variety may be used as source material for heat and drought tolerant cotton breeding. The results of this study may be useful for the cotton breeders to develop genotype adoptable to environmental stresses under climate change scenario.

Background Allergen tolerability due to allergic immune reactions could be transferred through the placenta from maternal to fetal circulation. Hence, a further investigation regarding the tolerability following mite allergen exposures is desirable. Objective To evaluate various doses of mite allergens and cytokines associated with Th1, Th2, and Treg cells with regards to possible allergic tolerance in neonatal mice. Methods This study used an experimental design with a post-test only control group, to assess the effect of mite allergens on pregnant BALB/C mice and their newborns. In this study female BALB/C mice aged 10 weeks were mated with male mice, then pregnant BALB/C mice were exposed to allergens at 4 weeks gestation. During pregnancy, pregnant females’ blood specimens were taken to measure cytokines and immunoglobulins. Meanwhile, neonatal blood specimens were taken at 2 weeks postnatally to measure cytokines and immunoglobulins. Blood specimens from pregnant BALB/C mice and their newborns were evaluated using ELISA kits for the following cytokines: interleukin (IL)-2, interferon (IFN)-γ, interleukin (IL)-4, IL-5, IL-10, TGF-β1, as well as immunoglobulins (Ig)G-1, IgG-2a, IgG-2b, IgG3 subclass, IgM, IgA, and IgE. The case group was the group that received high and low doses of exposure, while the control group did not get exposure. Results In response to low dose mite allergen exposure, there were significant increases of IL-2, IFN-y, and IL-4, IL-5, and TGF-β1 in mothers and neonates. Pregnant mices that received high doses of allergens, however, had significant increases in IL-5 and TGF-B1; results were likewise for their offspring. Mothers and neonates, had significantly increased expression of IgG subclasses after a low dose of dust mite allergen. Following a ten-fold increase in allergen dose, the mothers showed significant increases in IgA, IgM, IgE, and IgG subclasses, whereas in neonatal mice, those immunoglobulin levels were not significantly different from control mice. Conclusion Exposure to mite allergens can trigger regulatory functions of Th1, Th2, and Tregs cells to activate their cytokines, except IL-10. The regulatory function of Tregs is dominated by TGFβ in maternal and neonatal mice, at low and high doses. Th1 cytokines express cytokines during exposure only to low-dose allergens and Th2 cells regulate IL-5 levels to both low- and high-dose allergens.

BACKGROUND Oilseed rape requires sulfur (S) fertilization. Cadmium (Cd) differs dramatically in agricultural soils. Rice-oilseed rape rotation distributes widely and contributes the majority of rapeseeds in Asian countries. It was reported that S metabolism was involved in Cd uptake in seedlings of oilseed rape, although the effects of S on Cd accumulation and seed yield at maturity are still unclear. RESULTS We performed a pot experiment including two Cd rates (0.35 and 10.35 mg kg(-1), as low and high Cd soil) and four S levels (0, 30, 60 and 120 mg kg(-1)). The results showed that low S application (30 mg kg(-1)) resulted in two-fold higher seed-Cd concentration irrespective of soil Cd levels. The responsible mechanism might be that Cd translocation into rapeseeds was involved in sulfate transporters, which could be strongly expressed in shoots and roots when supplying sulfate under S-starvation conditions, but depressed under a S-sufficient environment. For high Cd soil, seed yield decreased by 36%, 48% and 72% at 30, 60 and 120 mg S kg(-1) compared to non-S treatment, whereas there were no differences for low Cd soil. Antagonistic effects of S and Cd existed for seed yield according to structure equation model analysis. CONCLUSION Oilseed rape can be grown in low-Cd fields as a safe food crop with high levels of sulfur fertilizers (>60 mg S kg(-1)). In high-Cd fields, oilseed rape is recommended as a Cd-remediation crop, and rapeseeds should only be used for industrial purposes and not for food. (c) 2021 Society of Chemical Industry.

Flight initiation distance (FID) procedures are used to assess the risk perception animals have for threats (e.g., natural predators, hunters), but it is unclear whether these assessments remain meaningful if animals have habituated to certain human stimuli (e.g., researchers, tourists). Our previous work showed that habituated baboons displayed individually distinct and consistent responses to human approaches, a tolerance trait, but it is unknown if the trait is resilient to life‐threatening scenarios. If it were consistent, it would imply FIDs might measure specific human threat perception only and not generalize to other threats such as predators when animals have experienced habituation processes. We used FID procedures to compare baseline responses to the visual orientation distance, FID, and individual tolerance estimates assessed after a leopard predation on an adult male baboon (group member). All variables were consistent despite the predation event, suggesting tolerance to observers was largely unaffected by the predation and FID procedures are unlikely to be generalizable to other threats when habituation has occurred. FID approaches could be an important tool for assessing how humans influence animal behavior across a range of contexts, but careful planning is required to understand the type of stimuli presented., We used flight initiation distance procedures to compare baseline responses to the visual orientation distance, FID, and individual tolerance estimates assessed after a leopard predation on an adult male baboon (group member). All variables remained consistent, suggesting tolerance to observers was unaffected by the predation event. FIDs may therefore not always be generalisable to other threats once habiutation processes have begun; however, they may still offer an important tool for assessing how humans influence the behaviour of animals in a range of scenarios.

Ash (Fraxinus spp.) is one of the most widely distributed tree genera in North America. Populations of ash in the United States and Canada have been decimated by the introduced pest Agrilus planipennis (Coleoptera: Buprestidae; emerald ash borer), having negative impacts on both forest ecosystems and economic interests. The majority of trees succumb to attack by A. planipennis, but some trees have been found to be tolerant to infestation despite years of exposure. Restriction site‐associated DNA (RAD) sequencing was used to sequence ash individuals, both tolerant and susceptible to A. planipennis attack, in order to identify single nucleotide polymorphism (SNP) patterns related to tolerance and health declines. de novo SNPs were called using SAMtools and, after filtering criteria were implemented, a set of 17,807 SNPs were generated. Principal component analysis (PCA) of SNPs aligned individual trees into clusters related to geography; however, five tolerant trees clustered together despite geographic location. A subset of 32 outlier SNPs identified within this group, as well as a subset of 17 SNPs identified based on vigor rating, are potential candidates for the selection of host tolerance. Understanding the mechanisms of host tolerance through genome‐wide association has the potential to restore populations with cultivars that are able to withstand A. planipennis infestation. This study was successful in using RAD‐sequencing in order to identify SNPs that could contribute to tolerance of A. planipennis. This was a first step toward uncovering the genetic basis for host tolerance to A. planipennis. Future studies are needed to identify the functionality of the loci where these SNPs occur and how they may be related to tolerance of A. planipennis attack., The majority of Fraxinus spp. individuals succumb to attack by Agrilus planipennis in North America, but some trees have been found to be tolerant to infestation despite years of exposure. Outlier SNPs (single nucleotide polymorphisms) were identified in a distinct cluster of Fraxinus individuals despite different geographic locations. This provides an initial step toward uncovering the genetic basis for host tolerance to A. planipennis.

Background Knowledge of the genetic diversity and population structure of germplasm collections is an important foundation for crop improvement. Rice production across a broad range of rice-growing environments results in a diverse array of local rice varieties. Many rice varieties have been lost as a result of biodiversity loss and are now grown in Pakistan. Methods and results To protect the biodiversity of rice varieties, an experiment was carried out to check the genetic and morphological variations between 8 exotic and 7 local rice genotypes, using 5 different SSR markers, i.e., RM3, RM259, RM341, RM520, and RM11943. The analysis of morphological and quality traits of rice observed significant variation across genotypes. The results revealed that genotype Irri-Pak attained the highest plant height and primary branch plant-1, while genotype Mushkan produced a higher number of productive tillers and obtained a higher fertility factor (%). Similarly, the highest value for panicle length was observed for genotype Faker-e-Malakand, 1000-grains weight in genotype Calmochi, and maximum days to maturity was noticed in genotype Swati-2014. Moreover, the genotype Brio attained the highest value of stem diameter, while maximum seed length was noted in the genotype Sug Dasi. The highest number of primary branches plant(-1) in genotype Ibge-I and secondary branches plant(-1) in genotype Calmochi were noticed. A higher concentration of sodium and potassium was observed for the genotype Marte, while the genotype Muskan attained the maximum content of copper. Moreover, the highest concentration of iron in genotype Originario, zinc in genotype JP-5, and cadmium content were noticed in genotype Ibge. Similarly, the dendrogram analysis for quantitative parameters showed three clusters at 74.13% similarities. Whereas all the genotypes of European origin formed a separate cluster. A set of 5 simple sequence repeat primers, covering four chromosomes, amplified a total of 14 alleles and showed 100% polymorphism with an average PIC value ranging from 0.39 to 0.91. The UPGMA cluster analysis separated the 15 rice genotypes into 3 main groups based on 32.5% similarities and the highest genetic distance (45.1%) was observed between two genotypes (Fakher-e-malakand and Musa), having different geographical origins. There was no genetic distance between the genotypes Marte and Brio, irrespective of having the same origin. Conclusions The maximum genetic distances were noted for genotype, Fakhre-e-Malakand and Musa having a different origin, while the minimum genetic distance was shown by genotypes, Marte and Onice, from the same origin.

This study aims to develop the socio-culture of Judo athletes. Judo provides socio-cultural values to each individual involved through the training process that is carried out, these socio-cultural values are expected to remain in the daily life of Judo athletes. This study used an experimental method with a one-group pretest-posttest design research design. The treatment carried out during the experiment was an integration of socio-cultural value education with the Judo training process. Treatment is given for 6 weeks with a frequency of 2 sessions/week, each session consisting of 120 minutes divided into 5 parts, namely introduction, explanation, discussion, ice breaking, and closing. The sample used in this study was 10 athletes from Bandung PPLPD Judo by using a total sampling approach. The instrument that the author uses in this study is the TQR-Questionnaire which is given twice to the sample. The results showed that there was a significant influence between Judo training and the increase in social-cultural values of athletes. This indicates that Judo training can be included in instilling socio-cultural values, especially in Judo athletes.

Made available in DSpace on 2022-04-29T08:32:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The indiscriminate use of fertilizers and chemical pesticides can lead to boron contamination of the soil. Decontamination in general is expensive and results in other impacts. Phytoremediation is a sustainable alternative for soil restoration. Astronium fraxinifolium Schott (Anacardiaceae) is a tree species native to the Cerrado that is considered to be a pioneer species and a selective xerophyte, and it has been widely used in the reforestation and restoration of degraded areas. This study set out to characterize the physiology and anatomy of A. fraxinifolium under different boron concentrations and to assess the tolerance and phytoremediation potential of the species. An experiment with a completely randomized design was conducted in a greenhouse. The carbon allocation and chlorophyll content of leaves of A. fraxinifolium were determined. Boron concentration and the species’ tolerance index were calculated from root and shoot samples. Levels of amino acids, proteins, total carbohydrates, starch, phenolic compounds, and anatomical analysis were also measured. A. fraxinifolium showed tolerance to boron concentrations in the substrate and accumulated a greater amount of the element in the aerial part, showing its phytoextraction ability. No significant differences were found in the physiology of A. fraxinifolium; however, some anatomical changes were observed. In the leaves, there were changes in the thickness of the abaxial surface of the epidermis and palisade and spongy parenchyma, and total leaf thickness, and in the roots, there were changes in the thickness of the phloem, diameter of vessel elements, and number of vessel elements per square millimeter. However, boron did not interfere in the development and survival of A. fraxinifolium, which points to the possibility that the species has phytoremediation potential. Faculdade de Engenharia de Ilha Solteira Department of Biology and Animal Science Universidade Estadual Paulista “Júlio de Mesquita Filho”, São Paulo Faculdade de Engenharia de Ilha Solteira Department of Biology and Animal Science Universidade Estadual Paulista “Júlio de Mesquita Filho”, São Paulo CNPq: 130355/2018-6 FAPESP: 2018/01498-6

Aquatic organisms rely on microbial symbionts for coping with various challenges they encounter during stress and for defending themselves against predators, pathogens and parasites. Microbial symbionts are also often indispensable for the host’s development or life cycle completion. Many aquatic ecosystems are currently under pressure due to diverse human activities that have a profound impact on ecosystem functioning. These human activities are also ex pected to alter interactions between aquatic hosts and their associated microbes. This can directly impact the host’s health and — given the importance and widespread occurrence of microbial symbiosis in aquatic systems — the ecosystem at large. In this review, we provide an overview of the importance of microbial symbionts for aquatic organisms, and we consider how the beneficial services provided by microbial symbionts can be affected by human activities. The scarcity of available studies that assess the functional consequences of human impacts on aquatic microbial symbioses shows that our knowledge on this topic is currently limited, making it difficult to draw general conclusions and predict future changes in microbial symbiont−host relationships in a changing world. To address this important knowledge gap, we provide an overview of ap proaches that can be used to assess the impact of human disturbances on the functioning of aquatic microbial symbioses. ispartof: AME vol:87 issue:Special 7 pages:113-138 status: published

In yellow soybean, severe cold weather causes seed cracking on the dorsal side. Yellow soybeans carry the I or ii allele of the I locus and have a yellow (I) or pigmented (ii) hilum. We previously isolated an additional allele, designated as Ic, of the I locus, and reported that yellow soybeans with the IcIc genotype may be tolerant to cold-induced seed cracking. The Ic allele by itself, however, does not confer high tolerance. The association of a pubescence color gene (T) with suppression of low-temperature-induced seed coat deterioration has been previously reported. In the present study, we tested whether T is effective for the suppression of cold-induced seed cracking using two pairs of near-isogenic lines for the T locus in the iiii or IcIc background. In both backgrounds, the cracked seed rate of the near-isogenic line with the TT genotype was significantly lower than that with the tt genotype, which indicates that T has an inhibitory effect on cold-induced seed cracking. Furthermore, we also showed that gene pyramiding of Ic and T can improve tolerance to cold-induced seed cracking. Our findings should aid the development of highly SC-tolerant cultivars in soybean breeding programs.

Key message Root-specific expression of a cytokinin-degrading CKX gene in maize roots causes formation of a larger root system leading to higher element content in shoot organs. Abstract The size and architecture of the root system is functionally relevant for the access to water and soil nutrients. A great number of mostly unknown genes are involved in regulating root architecture complicating targeted breeding of plants with a larger root system. Here, we have explored whether root-specific degradation of the hormone cytokinin, which is a negative regulator of root growth, can be used to genetically engineer maize (Zea mays L.) plants with a larger root system. Root-specific expression of a CYTOKININ OXIDASE/DEHYDROGENASE (CKX) gene of Arabidopsis caused the formation of up to 46% more root dry weight while shoot growth of these transgenic lines was similar as in non-transgenic control plants. The concentration of several elements, in particular of those with low soil mobility (K, P, Mo, Zn), was increased in leaves of transgenic lines. In kernels, the changes in concentration of most elements were less pronounced, but the concentrations of Cu, Mn and Zn were significantly increased in at least one of the three independent lines. Our data illustrate the potential of an increased root system as part of efforts towards achieving biofortification. Taken together, this work has shown that root-specific expression of a CKX gene can be used to engineer the root system of maize and alter shoot element composition.

Flooding threatens the functioning of managed grasslands by decreasing primary productivity and increasing nitrogen losses, notably as the potent greenhouse gas nitrous oxide (N2O). Sowing species with traits that promote flood resilience and mitigate flood-induced N2O emissions within these grasslands could safeguard their productivity while mitigating nitrogen losses. We tested how plant traits and resource acquisition strategies could predict flood resilience and N2O emissions of 12 common grassland species (eight grasses and four legumes) grown in field soil in monocultures in a 14-week greenhouse experiment. We found that grasses were more resistant to flooding while legumes recovered better. Resource-conservative grass species had higher resistance while resource-acquisitive grasses species recovered better. Resilient grass and legume species lowered cumulative N2O emissions. Grasses with lower inherent leaf and root δ13C (and legumes with lower root δ13C) lowered cumulative N2O emissions during and after the flood. Our results highlight the differing responses of grasses with contrasting resource acquisition strategies, and of legumes to flooding. Combining grasses and legumes based on their traits and resource acquisition strategies could increase the flood resilience of managed grasslands, and their capability to mitigate flood-induced N2O emissions. A free Plain Language Summary can be found within the Supporting Information of this article.

Summary Heterogeneity for plant defences determines both the capacity of host populations to buffer the effect of infection and the pathogen´s fitness. However, little information is known on how host population structure for tolerance, a major plant defence, impacts the evolution of plant–pathogen interactions.By performing 10 serial passages of Turnip mosaic virus (TuMV) in Arabidopsis thaliana populations with varying proportion of tolerant genotypes simulating different structures for this trait, we analysed how host heterogeneity for this defence shapes the evolution of both virus multiplication, the effect of infection on plant fecundity and mortality, and plant tolerance and resistance.Results indicated that a higher proportion of tolerant genotypes in the host population promotes virus multiplication and reduces the effect of infection on plant mortality, but not on plant fecundity. These changes resulted in more effective plant tolerance to virus infection. Conversely, a lower proportion of tolerant genotypes reduced virus multiplication, boosting plant resistance.Our work for the first time provides evidence of the main role of host population structure for tolerance on pathogen evolution and on the subsequent feedback loops on plant defences.

Objectives New antituberculosis agents active against drug-resistant and non-replicating tubercle bacilli are required. We evaluated a previously identified hit, 2-(((2-hydroxyphenyl)amino)methylene)-5,5-dimethylcyclohexane-1,3-dione (PAMCHD), against several clinical Mycobacterium tuberculosis isolates, including multidrug-resistant (MDR) strains and non-replicating drug-tolerant persisters of M. tuberculosis H37Rv. Methods PAMCHD's potential against drug-resistant M. tuberculosis was investigated by broth microdilution. CFU enumeration was performed to determine PAMCHD's activity against five types of dormant bacilli. Results No significant differences in MICs of PAMCHD were observed against M. tuberculosis H37Rv (2.5–5 µg/mL) and eight drug-susceptible strains (1.25–5 µg/mL) as well as drug-resistant strains including six isoniazid (INH)-resistant (2.5–10 µg/mL), one INH + ethambutol (EMB)-resistant (5 µg/mL), one rifampicin (RIF) + EMB-resistant (5 µg/mL) and three MDR (2.5–10 µg/mL) strains. Thus, PAMCHD maintains activity against all kinds of clinical strains, especially MDR. Regarding drug-tolerant persisters, INH and RIF killed, respectively, 0.5 and 5.0 log10 CFU of non-replicating persisters developed by hypoxia and 1.5 and 2.5 log10 CFU developed by nutrient starvation at 64 × of their respective MIC against actively dividing cultures. In contrast, PAMCHD sterilised persister cultures developed by hypoxia (killed 6.5 log10 CFU) or starvation (killed 7.5 log10 CFU). PAMCHD sterilised RIF-tolerant (tolerance level up to 100 µg/mL of RIF) 100-day-old static persisters at 64 × MIC, while moxifloxacin killed only 1.0 log10 CFU of these persisters at 64 × MIC. Conclusion PAMCHD offers significant potential against MDR-TB and exhibits notable potency against non-replicating drug-tolerant M. tuberculosis persisters. These findings warrant further studies of PAMCHD for further anti-TB drug development.

BackgroundTea is an important plantation crop in India and world. Introduction of fertilisers and pesticides for better production polluted tea garden soils. Phosphates in agricultural soils are converted into soluble forms by phosphate solubilising microorganisms (PSMs). Consortium of PSM having high tolerance level is an attractive option for bioremediation of degraded tea plantation soils. This research initiative was to isolate PSM from tea plantation soil and detect their tolerance against pesticide, antibiotic and antifungal.ResultsIsolated consortia from organic and inorganic tea plantation soils of Darjeeling showing halo was considered for tolerance study. Phorate was most and Deltamethrin was the least tolerant pesticide for the isolated PSM consortia. So, Phorate may be considered as most used or most accumulated pesticide. Erythromycin was most and Ofloxacin was the least tolerant antibiotic while Fluconazole was most and Itraconazole was the least tolerant antifungal agent for the isolated PSM consortia. It was noted that there was no or partial inhibition of PSM growth by some pesticide, antibiotic and antifungal agents. In all the three tolerance studies it was observed that there is no relation between collection sites but in all the assays average inhibition zones were more in organic plantations than inorganic plantations.ConclusionsThus, it may be said that inorganic practice induces tolerance to microbes. So, other than cultural practice use of chemicals, micro-ecosystem and antibiosis exhibited by microbes do play a role in conferring tolerance.

Lichens have widely been used as bioindicators to reflect the quality of the environment. The present study was conducted to investigate the lichens diversity that grows on the surface of waste heaps from an abandoned old copper mine in Mlynky, Slovakia. In spite of the heavy metalcontaminated environment, we documented twenty species of lichens in the selected site. Taxonomically the most numerous group were represented by Cladonia with seven species, as well other species; namely, Acarospora fuscata, Cetraria islandica, Dermatocarpon miniatum, Hypogymnia physodes, Hypogymnia tubulosa, Lecanora subaurea, Lepraria incana, Physcia aipolia, Porpidia macrocarpa, Pseudevernia furfuracea, Rhizocarpon geographicum and Xanthoria parietina. The content of selected heavy metals (Cu, Fe, and Zn) in the predominant lichens Cetraria islandica, Cladonia digitata, Cladonia pyxidata, Hypogymnia physodes and Pseudevernia furfuracea were analyzed. The highest content of Cu, Fe, and Zn was found in Cladonia pyxidata collected from mine-spoil heaps with concentration 46 ± 4.4, 82.5 ± 22.6, 4.8 ± 1.6 mg/kg, respectively. Interestingly, Cladonia pyxidata collected from the forest surrounding the location showed 15 times lower concentration for Cu. Additionally, similar results were found for Fe and Zn.

The prevalence and deficient control with glyphosate in some weeds in banana (Musa × paradisiaca L.) plantations in the Department of Magdalena, Colombia, have been evidenced. The susceptibility to glyphosate of prevalent weeds in farms with more than 10 yr of application of this herbicide was evaluated. Seeds and propagules of adult plants of five weedy species were collected from farms where deficient glyphosate control was observed (populations with possible resistance) and in areas not cultivated or free of herbicide use (susceptible populations). Under controlled conditions, seedlings obtained from 17 populations were treated with a commercial dose of glyphosate (1440 g acid equivalent [ae] ha-1) or twice this dose (2880 g ae ha-1). At 21 d after application, populations with a relative fresh weight and survival greater than 20% and visual control lower than 80% were categorized as resistant populations. To determine the resistance factor (RF) in the resistant populations, bioassays were performed with increasing doses of the herbicide (0, 720, 1440, 2880, 5760, and 11 520 g ae ha-1). Populations of Echinochloa colona (L.) Link and Melothria pendula L. were sensitive to both doses, while the populations of Commelina erecta L. and Syngonium podophyllum Schott were not controlled, confirming glyphosate-tolerant. Populations of Erigeron bonariensis L., from uncultivated areas was susceptible, while those from farms were resistant. Glyphosate-resistance was confirmed in two populations of E. bonariensis, with respective RF of 3.5 and 8.6. The repetitive application of glyphosate for weed control in the Magdalena banana farms has contributed to the prevalence of tolerant species and the appearance of herbicide-resistant weeds.

Soil salinity is among the major abiotic stresses that plants must cope with, mainly in arid and semiarid regions. The tolerance to high salinity is an important agronomic trait to sustain food production. Quinoa is a halophytic annual pseudo-cereal species with high nutritional value that can secrete salt out of young leaves in external non-glandular cells called epidermal bladder cells (EBC). Previous work showed high salt tolerance, but low EBC density was associated with an improved response in the early phases of salinity stress, mediated by tissue-tolerance traits mainly in roots. We compared the transcript profiling of two quinoa genotypes with contrasting salt tolerance patterning to identify the candidate genes involved in the differentially early response among genotypes. The transcriptome profiling, supported by in vitro physiological analyses, provided insights into the early-stage molecular mechanisms, both at the shoot and root level, based on the sensitive/tolerance traits. Results showed the presence of numerous differentially expressed genes among genotypes, tissues, and treatments, with genes involved in hormonal and stress response upregulated mainly in the sensitive genotype, suggesting that tolerance may be correlated to restricted changes in gene expression, at least after a short salt stress. These data, showing constitutive differences between the two genotypes, represent a solid basis for further studies to characterize the salt tolerance traits. Additionally, new information provided by this work might be useful for the development of plant breeding or genome engineering programs in quinoa.

Made available in DSpace on 2021-06-25T10:50:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) This study investigated the potential for tolerance, absorption, and translocation of iron (Fe) by Leucaena leucocephala, as well as the response of the photosynthetic mechanism and the phytoremediation potential of L. leucocephala grown in soil with concentrations of Fe (0, 100, 200, 300, 400, and 500 mg Fe/dm3 of soil). The chlorophyll content and the photosynthetic apparatus showed a significant difference between treatments: the chlorophyll content, transpiration rate, and stomatal conductance were higher in the treatment 200 mg Fe/dm3 of soil, while the photosynthetic rate was higher in the treatment 500 mg Fe/dm3 of soil in relation to the control. From 300 mg Fe/dm3 of soil onward, there was a significant reduction in the number of leaves, mass, and biomass of L. leucocephala. The species is tolerant to the Fe doses analyzed. Availability of Fe in the soil after the cultivation of L. leucocephala decreased, evidencing the plant capacity of Fe absorption, which accumulated mostly in the roots, and only % of Fe was translocated to the shoots. The highest Fe accumulation per biomass was 9.48 mg, at 200 mg Fe/dm3 of soil. The amount of Fe translocated and accumulated in L. leucocephala is directly related to its biomass production thus the dose 200 mg Fe/dm3 of soil allows the best performance of phytoremediation potential. Although plant growth is affected by treatments of 300, 400 and 500 mg Fe/dm3 of soil and Fe accumulation is less, L. leucocephala is able to tolerate and phytostabilize soil Fe with potential for use in phytoremediation, mainly because it is a kind of phytostabilization of Fe. Department of Biology and Zootechny São Paulo State University (Unesp) School of Engineering Ilha Solteira. Plant Metabolism Physiology Laboratory. Rua Monção, 226, Rua Monção, 226, Zona Norte Instituto Federal Goiano Rede Arco Norte/Polo de Inovação em Bioenergia e Grãos, Campus Rio Verde Federal University of Alagoas State (UFAL) and Health Science Institute, Botany Setor, Avenida Lourival Melo Mota s/n Mathematics Department São Paulo State University (Unesp) School of Engineering, Ilha Solteira. Av. Brazil Sul, Centro Department of Biology and Zootechny São Paulo State University (Unesp) School of Engineering Ilha Solteira. Plant Metabolism Physiology Laboratory. Rua Monção, 226, Rua Monção, 226, Zona Norte Mathematics Department São Paulo State University (Unesp) School of Engineering, Ilha Solteira. Av. Brazil Sul, Centro FAPESP: 2018/13008-3 e 2018/01498-6

Background Resistance and tolerance are two coexisting defense strategies for fighting infections. Resistance is mediated by signaling pathways that induce transcriptional activation of resistance factors that directly eliminate the pathogen. Tolerance refers to adaptations that limit the health impact of a given pathogen burden, without targeting the infectious agent. The key players governing immune tolerance are largely unknown. In Drosophila, the histone H3 lysine 9 (H3K9) methyltransferase G9a was shown to mediate tolerance to virus infection and oxidative stress (OS), suggesting that abiotic stresses like OS may also evoke tolerance mechanisms. In response to both virus and OS, stress resistance genes were overinduced in Drosophila G9a mutants, suggesting an intact but overactive stress response. We recently demonstrated that G9a promotes tolerance to OS by maintaining metabolic homeostasis and safeguarding energy availability, but it remained unclear if this mechanism also applies to viral infection, or is conserved in other species and stress responses. To address these questions, we analyzed publicly available datasets from Drosophila, mouse, and human in which global gene expression levels were measured in G9a-depleted conditions and controls at different time points upon stress exposure. Results In all investigated datasets, G9a attenuates the transcriptional stress responses that confer resistance against the encountered stressor. Comparative analysis of conserved G9a-dependent stress response genes suggests that G9a is an intimate part of the design principles of stress resistance, buffering the induction of promiscuous stress signaling pathways and stress-specific resistance factors. Importantly, we find stress-dependent downregulation of metabolic genes to also be dependent on G9a across all of the tested datasets. Conclusions These results suggest that G9a sets the balance between activation of resistance genes and maintaining metabolic homeostasis, thereby ensuring optimal organismal performance during exposure to diverse types of stress across different species. We therefore propose G9a as a potentially conserved master regulator underlying the widely important, yet poorly understood, concept of stress tolerance.

Theresistance mechanisms exhibited by the five selected maize varieties against Ostrinia furnacalis [Gueene] or the Asian corn borer (ACB) were identified and evaluated in the study in terms of the insects’ percent mortality and development. The detached leaf-feeding assay was used in the experiment and laid out in Complete Randomized Design (CRD) with 5 treatments and replicated three times. Findings among the five selected maize varieties tested against ACB, Bt corn had exhibited a high degree of antibiosis mechanism. This was expected because of the Bt toxin from the maize variety conferring toxicity to Lepidopterous insect pests like ACB. A similar result with Variety 4 (Yellow Dent corn) was observed which shows a high degree of antibiosis mechanism that is innate within the maize leaves of the variety. Variety 1 (UPLB Lagkitan), Variety 2 (Yellow corn), and Variety 3 (White corn) show high susceptibility to ACB. Tolerance of the corn varieties to ACB needs to be further investigated because it is unknown to date whether the varieties possess or lack plant tolerance characteristics. Leaf whorl feeding assays used in the study only measure the antibiosis and antixenosis mechanisms in maize. Furthermore, a test to measure tolerance mechanisms is suggested among the maize varieties.

In 2017-2020 in the conditions of Kirov region there were studied 143 varieties, 115 perspective lines and 28 hybrids of the first generation of spring soft wheat according to the degree of resistance to septoria tritici blotch against the background of the natural development of infection. It has been established that development of the disease significantly increased with a decrease in air temperature during the «seedling-tillering» phase (r = -0.83…-0.96) and an increase in the amount of precipitation during «shooting» phase (r = +0.87…+0.90). Resistance to septoria tritici blotch was shown by 16.1 % collection samples. A significant (r = -0.83) decrease in yield by an average of 19 % in susceptible samples compared to resistant ones was revealed. The greatest breeding and immunological value were represented by the varieties of Russian selection: Tobolskaya, Tyumenskaya 29, Moskovskaya 35 and МIS, among which the early variety MIS was tolerant to septoria tritici blotch. Thirteen lines resistant to septoria tritici blotch were identified from the new breeding material. The varieties selected for resistance to septoria tritici blotch were used in hybridization. In F1hybrids domination and overdomination in the inheritance of resistance to septoria tritici blotch prevailed, as well as weight of 1000 grains and yield per 1 m2. Among them, 8 hybrids F1 with the highest values of the dominance indices were identified. It has been established, that inheritance of resistance to septoria tritici blotch, weight of 1000 grains and yield of hybrids F1 occurs both in the maternal and paternal lines. The greatest immunological effect was obtained when using the varieties Daria (Russia) and Epos (Germany). The most productive hybrids were the variety Daria, taken as both a maternal and paternal form, as well as when using the Egisar 29 (Russia) variety as a maternal form.

Animal cooperation in the wild often involves multiple individuals that must tolerate each other in close proximity. However, most cooperation experiments in the lab are done with two animals, that are often also physically separated. Such experiments are useful for answering some pertinent questions, for example about the understanding of the role of the partner and strategies of partner control, but say little about factors determining successful cooperation with multiple partners in group settings. We explored the influence of dominance, rank distance, tolerance, affiliation, and coordination by testing kea parrots with a box requiring two, three, or four chains to be pulled simultaneously to access food rewards. The reward could be divided unevenly, but not monopolized completely. Eventually dyadic, triadic, and tetradic cooperation tasks were solved, showing that non-human animals are capable of tetradic cooperation in an experimental setup. Starting with two chains, we found that in a dyad monopolization of the box by the highest-ranking bird was the largest obstacle preventing successful cooperation. High-ranking birds learned to restrain themselves from monopolizing the box during a single session in which monopolization was hindered by the presence of a large number of birds. Thereafter, restraint by dominants remained the strongest factor determining success in the first trial in dyadic, triadic, and tetradic setups. The probability of success increased with the degree of restraint shown by all dominant subjects present. Previous experience with the task contributed to success in subsequent sessions, while increasing rank distance reduced success notably in the four-chain setup. Supplementary Information The online version contains supplementary material available at 10.3758/s13420-021-00462-9.

Highlights • All tested phytochemicals induce the transcription of at least some P450s. • Clan 3 (particularly family 6) in insects and clan 2 in mites are most responsive. • Induction of P450s is mainly studied in polyphagous arthropod herbivores. • Regulation of P450 induction upon phytochemicals exposure is underexplored., Cytochrome P450 monooxygenases (P450s) play a key role in the detoxification of phytochemicals in arthropod herbivores. We present here an overview of recent progress in understanding the breadth and specificity of gene expression plasticity of P450s in response to phytochemicals. We discuss experimental setups and new findings in mechanisms of P450 regulation. Whole genome transcriptomic analysis of arthropod herbivores, either after direct administration of phytochemicals or after host plant shifts, allowed to integrate various levels of chemical complexity and lead to the unbiased identification of responsive P450 genes. However, despite progress in identification of inducible P450s, the link between induction and metabolism is still largely unexplored, and to what extent the overall response is biologically functional should be further investigated. In the near future, such studies will be more straightforward as forward and reverse genetic tools become more readily available.

Improving early diagnosis along with timely and effective treatment of COVID-19 are urgently needed. However, at present, the mechanisms underlying disease spread and development, defined prognosis, and immune status of patients with COVID-19 remain to be determined. Patients with severe disease state exhibit a hyperinflammatory response associated with cytokine storm syndrome, hypercoagulability, and depressed cell-mediated immunity. These clinical manifestations, sharing similar pathogenesis, have been well-studied in patients with advanced ovarian cancer. The present review suggests treatment approaches for COVID-19 based on strategies used against ovarian cancer, which shares similar immunopathology and associated coagulation disorders.The chronicization of the hyperinflammatory cytokine storm in patients with severe COVID-19 highlights a defective resistance phase that leads to aspecific chronic inflammation, associated with oxidative stress, which impairs specific T-cell response, induces tissue and endothelial damage, and thrombosis associated with systemic effects that lead to severe multi-organ failure and death. These events are similar to those observed in advanced ovarian cancer which share similar pathogenesis mediated primarily by Interleukin-6, which is, as well demonstrated in ovarian cancer, the key cytokine driving the immunopathology, related systemic symptoms, and patient prognosis.Consistent with findings in other disease models with similar immunopathology, such as advanced ovarian cancer, treatment of severe COVID-19 infection should target inflammation, oxidative stress, coagulation disorders, and immunodepression to improve patient outcome. Correctly identifying disease stages, based on available laboratory data, and developing a specific protocol for each phase is essential for effective treatment.

Late embryogenesis abundant (LEA) proteins play an important role in plant growth and development, as well as in the plant response to various abiotic stresses. In this study, CsLEA1, a novel gene encoding a LEA_3 subfamily protein, was successfully cloned from a tea plant [Camellia sinensis (L.) O. Kuntze]. Bioinformatics analysis and prokaryotic expression assays showed that CsLEA1 is a typical hydrophilic protein with a molecular weight of approximately 10.4 kD. Expression analyses revealed that the transcription of CsLEA1 in C. sinensis leaves was significantly induced by cold stress. In addition, the heterologous expression of CsLEA1 increased the tolerance of Escherichia coli and yeast to cold stress, which might be closely related to the low molecular weight and high hydrophilicity of the CsLEA1. Taken together, our results suggest that CsLEA1 might have an important function in the tolerance of C. sinensis to cold stress, thus providing a potential application in molecular breeding to enhance the cold stress tolerance of tea plants.

Background: Venom immunotherapy (VIT) is highly efficient in subjects suffering from IgE-mediated allergy to hymenoptera venom (HV), and VIT results in substantial improvement of quality of life (QoL). However, VIT-induced tolerance may be lost over time after cessation of treatment, putting patients at risk of re-sting anaphylaxis. Materials and methods: To study the effect of VIT on maintenance of HV tolerance we evaluated the natural history of 54 patients who were treated with VIT up to 29 years ago, with a special focus on re-stings and their subsequent course. Furthermore, we analyzed HV-specific IgE, IgG, and IgG4 antibody titers. Finally, we assessed the long-term impact of VIT on various psychosocial aspects like dealing with hymenoptera exposures, daily life activities, self-assurance, and personal environment. Results: 29 (53.7%) subjects experienced at least one re-sting after stopping VIT, with 23 (79%) showing no systemic reaction (SR). Eleven of these (37.9%) took emergency drugs as a safety measurement. Six individuals (21%) showed loss of tolerance experiencing an anaphylactic reaction. No difference in HV-specific IgE, IgG4, or IgG antibody concentrations was noticed among the different patients. Subjects who tolerated a re-sting without applying emergency drugs felt least affected in their social-behavioral leisure activities when hymenoptera were around or by anxiety for new stings. Conclusion: VIT leads to long-term tolerance in the majority of HV-allergic patients, however, ~ 1/5 may lose protection over time, arguing for continued follow-up on VIT-treated subjects and keeping them equipped with an emergency kit. Notably, VIT also results in a lasting, strong impact on self-assurance and sense of well-being in individuals who tolerated a re-sting without employing emergency drugs, which emphasizes the need to use them only in case of systemic symptoms after stopping successful VIT.

Various stresses are commonly encountered by probiotics in their ecological niches. Effects of adaptation treatments on the heat tolerance of Lactobacillus plantarum KLDS 1.0628 were evaluated. Cells pre-adapted to heat, cold, oxidative, acid, bile salt, and osmotic stresses were evaluated for tolerance and cross-protection against subsequent challenge. Except for cold, pre-adaptation to sublethal levels of stress significantly improved the cell viability after heat challenge compared to the control. Heat-adapted cells showed the highest heat stress tolerance, with their tolerance factor against heat challenge reaching 31.38-fold after pre-adaptation at 45°C for 1 h. Moreover, adaptation treatments improved tolerance to the same stress and evoked cross-protection against heterologous challenges, inducing a significantly lower ratio of saturated to unsaturated fatty acid content in the cell membrane of L. plantarum KLDS 1.0628. The results indicated that adaptation treatments are potential strategies for enhancing the survival rate of probiotics and exerting their functional properties.

Background Systemic reactions and anaphylaxis due to Hymenoptera venoms occur in up to 7.5% of the European population. Fatal sting reactions are very rare. Serum tryptase levels should be measured in all patients with a history of severe reactions in order to detect mastocytosis and to determine the risk of severe reactions to venom immunotherapy (VIT). The risk to experience severe or even fatal anaphylaxis due to insect stings is quite high in patients with mastocytosis. Therefore, lifelong VIT is recommended in these highly threatened patients. Multicenter studies involving a large population report that up to 20% of patients undergoing VIT have intolerance and systemic reactions to immunotherapy. Some of these side effects occur repeatedly and cannot be managed by standard treatment. A pre-treatment with the anti-IgE antibody omalizumab was useful in many cases. However, omalizumab is not approved for the indication anaphylaxis. Therefore, there is still no defined protocol for omalizumab pre-treatment, and the optimal duration, dosage as well as long-time benefits are still unclear. Case report We present a 60-year-old female patient with mastocytosis who developed a severe anaphylactic reaction during initiation of bee VIT. Serum tryptase was elevated, and a KIT mutation D816V was subsequently confirmed. Component-resolved diagnostic tests revealed specific IgE antibodies to recombinant Api m 1 only. The patient was treated with 150 mg omalizumab, administered subcutaneously 5 weeks, 3 weeks, and 1 week prior to re-start of immunotherapy and for 2 months in parallel to VIT. Updosing was done by a 7-day rush schedule. During this period, no anaphylactic reaction developed, and the bee VIT was well tolerated with up to 200 µg bee venom. The patient is currently in the 3rd year of treatment and tolerates the treatment very well. Conclusion Omalizumab may be used as a premedication in patients with mastocytosis who do not tolerate VIT. Although there is no consensus on the treatment protocol, treatment for 2 - 6 months is considered adequate. The long-term benefits of such treatment require further research.

As wheat (Triticum aestivum) is an important staple food across the world, preservation of stable yields and increased productivity are major objectives in breeding programs. Drought is a global concern because its adverse impact is expected to be amplified in the future due to the current climate change. Here, we analyzed the effects of edaphic, environmental, and host factors on the wheat root microbiomes collected in soils from six regions in Belgium. Amplicon sequencing analysis of unplanted soil and wheat root endosphere samples indicated that the microbial community variations can be significantly explained by soil pH, microbial biomass, wheat genotype, and soil sodium and iron levels. Under drought stress, the biodiversity in the soil decreased significantly, but increased in the root endosphere community, where specific soil parameters seemingly determine the enrichment of bacterial groups. Indeed, we identified a cluster of drought-enriched bacteria that significantly correlated with soil compositions. Interestingly, integration of a functional analysis further revealed a strong correlation between the same cluster of bacteria and β-glucosidase and osmoprotectant proteins, two functions known to be involved in coping with drought stress. By means of this in silico analysis, we identified amplicon sequence variants (ASVs) that could potentially protect the plant from drought stress and validated them in planta. Yet, ASVs based on 16S rRNA sequencing data did not completely distinguish individual isolates because of their intrinsic short sequences. Our findings support the efforts to maintain stable crop yields under drought conditions through implementation of root microbiome analyses. ispartof: COMPUTATIONAL AND STRUCTURAL BIOTECHNOLOGY JOURNAL vol:19 pages:4235-4247 ispartof: location:Netherlands status: published

Despite widespread abuse, high socioeconomic costs, and substantial research investment, the basic mechanisms of alcohol action on the brain remain poorly understood. This is partly due to the physiological complexity of alcohol’s effects and the long term progressive nature of alcohol use disorders (AUDs). Further, mammalian models of AUD endophenotypes require high levels of resources and time. One approach that has promise is to use invertebrate model organisms to understand the molecular and cellular mechanisms of behavioral adaptations to acute ethanol exposure. The fruit fly Drosophila, is a classic model organism for defining the molecules and neural circuits that drive animal behavior. The molecular makeup of the fly brain is remarkably conserved with that of mammals. Moreover, both flies and humans have a long history of association with alcohol, suggesting that behaviors like craving, drinking, and reward are coded similarly. Indeed, dopamine signaling underlies the hyperactivating and rewarding properties of ethanol across species. Flies, like humans, become inebriated, develop ethanol tolerance, ethanol preference, and ethanol reward associations, and they show signs of withdrawal. Many of these are adaptations to ethanol exposure that are forms of behavioral plasticity. How ethanol behavioral plasticity differs from non-addictive forms is key to understanding why some substances are abused. The goal of the research for this thesis was to ask if glial cells, like neuronal cells, promote behavioral plasticity induced by acute ethanol. Glial cells perform surprisingly diverse functions in the brain, including information transmission whose regulation is key to behavioral plasticity. A survey of the Drosophila glial types uncovered roles in ethanol tolerance for two types, the astrocytes that contact and regulate neuronal synapses, and the perineurial cells that form the outer surface of the blood-brain barrier. Dysregulation of glutamate homeostasis in astrocytes renders flies sensitive to acute inebriation and decreased ethanol tolerance. These ethanol phenotypes correlate with others that are early signatures of neurodegeneration caused by glutamate excitotoxicity. Perineurial cells show morphological change that correlated with reduced actin organization following acute ethanol exposure. This morphological change required Akap200, an adaptor protein that coordinates protein kinase A, protein kinase C, calcium, and actin at the perineurial plasma membrane. Loss of Akap200 either globally or specifically in the perineurium decreases ethanol tolerance development, as does disruption of many of the molecules that interact with Akap200. These Akap200 dependent functions appear to be occurring at the time of ethanol exposure. These findings indicate an active signaling role for the blood-brain barrier in the development of ethanol tolerance, and they imply that the barrier and neurons communicate to promote behavioral plasticity.

Agricultural landscape intensification has enabled food production to meet growing demand. However, there are concerns that more simplified cropland with lower crop diversity, less noncrop habitat, and larger fields results in increased use of pesticides due to a lack of natural pest control and more homogeneous crop resources. Here, we use data on crop production and insecticide use from over 100,000 field-level observations from Kern County, California, encompassing the years 2005–2013 to test if crop diversity, field size, and cropland extent affect insecticide use in practice. Overall, we find that higher crop diversity does reduce insecticide use, but the relationship is strongly influenced by the differences in crop types between diverse and less diverse landscapes. Further, we find insecticide use increases with increasing field size. The effect of cropland extent is distance-dependent, with nearby cropland decreasing insecticide use, whereas cropland further away increases insecticide use. This refined spatial perspective provides unique understanding of how different components of landscape simplification influence insecticide use over space and for different crops. Our results indicate that neither the traditionally conceived “simplified” nor “complex” agricultural landscape is most beneficial to reducing insecticide inputs; reality is far more complex.

Purpose Involvement in sport is common among prospective medical students and may serve as a foundation for the psychological wellbeing of future physicians. This study examined the relationship between medical students’ sport background and their tolerance of ambiguity and uncertainty, an established factor in physician wellbeing and a key component in quality patient care. Method Sixty-one 3rd year medical students (50% females) at a large Canadian university responded to a web-based survey (62% response rate). The survey included the 29-item TAMSAD (Tolerance of Ambiguity in Medical Students and Doctors) scale and sport background measures (sport type and level of involvement). Analysis of variance and correlational analysis were performed. Results Analysis of variance indicated a significant mean difference in students’ TAMSAD scores based on sport type. Individual sport participants reported on average higher tolerance of ambiguity and uncertainty than team sport participants. However, in team sport participants, their tolerance of ambiguity and uncertainty tended to increase with an increase in sport involvement (from recreational to competitive). Discussion The gained insights are valuable as involvement in dedicated, extracurricular activities such as sport has not been studied in relation to ambiguity and uncertainty tolerance in medical students. The findings have implications for medical education and professional practice. Medical students and physicians could draw on the attributes and skills developed in sport when responding to ambiguity and uncertainty in clinical settings. Those without a sport background could learn and apply some of the strategies athletes use to tackle setbacks and uncertainty in high-stakes situations. Medical school admissions, curriculum designers, and educators could use the knowledge in developing interview questions, designing educational innovations, and selecting instructional strategies for teaching clinical reasoning and decision making. Future research should include qualitative studies to provide in-depth explanations for the relationships observed in this study.

The current interest of scientific study aims at survival mechanisms of the cyanobacteria on the extreme habitats (i.e. building facades and monuments) growing under adverse conditions. The present investigation points towards finding out indigenous which are tolerant of conflicting environmental conditions, such as pH, temperature and calcium carbonate. Three isolates of cyanobacteria Scytonema coactile, Scytonema geitleri and Lyngbya aerugineo–coerulea from a cave, building façade, and temple, Orissa respectively were examined. Tolerance to stress at different pH and temperature were evaluated by quantifying cyanobacteria growth at different time intervals. Tolerance to CaCO3 was studied by subjecting the isolates to the desired concentration 0.0001 – 1% w/v. Each organism was grown for 15 days at 25°C ± 1°C under continuous light intensity (7.5 W/m2) and then harvested, succeeded by SDS gel-electrophoresis protein analysis. Results revealed that three isolated cyanobacteria species from different sub-aerial habitats responded in a specific manner to different stress conditions and to various concentration of CaCO3 concerning protein synthesis. A 30 and 38 kDa protein was overproduced by all isolates under pH and temperature stress, whereas for CaCO3 stress, the protein of 16 and 22 kDa was overproduced by Lyngbya aerugineo–coerulea respectively which concluded that the survival of the isolates under stress conditions depends on specific protein synthesis. Generally, isolates tolerant to different stress may be due to specific protein synthesis for their survival to extreme habitats.

Varroa destructor is an ectoparasitic mite of immature and adult honey bees that can transmit several single-stranded RNA viruses to its host. Varroa reproduce in brood cells, and mite populations increase as colonies produce brood in spring and summer. Mite numbers also can sharply rise, particularly in the fall, by the migration of varroa into hives on foragers. Colonies with high levels of varroa and viruses often die over the winter. Feeding colonies pollen might keep virus levels low and improve survival because of the positive effects of pollen on immunity and colony growth. We compared varroa and virus levels and overwinter survival in colonies with (fed) and without (unfed) supplemental pollen. We also measured the frequency of capturing foragers with mites (FWM) at colony entrances to determine its relationship to varroa and virus levels. Colonies fed supplemental pollen were larger than unfed colonies and survived longer. Varroa populations and levels of Deformed wing virus (DWV) rose throughout the season, and were similar between fed and unfed colonies. The growth of varroa populations was correlated with FWM in fed and unfed colonies, and significantly affected DWV levels. Increasing frequencies of FWM and the effects on varroa populations might reduce the positive influence of supplemental pollen on immune function. However, pollen feeding can stimulate colony growth and this can improve colony survival. Electronic supplementary material The online version of this article (10.1007/s10493-020-00562-7) contains supplementary material, which is available to authorized users.

We have examined the response of memory CD4 T cells to tolerogenic signals. Although memory CD4 T cells could respond to antigen delivered without adjuvant, they undergo cell death upon further restimulation. Our data suggest that the Tcells die as a consequence of mitotic catastrophe that occurs when cells are unable to complete cell division., Summary Memory T cells respond rapidly in part because they are less reliant on a heightened levels of costimulatory molecules. This enables rapid control of secondary infecting pathogens but presents challenges to efforts to control or silence memory CD4 T cells, for example in antigen‐specific tolerance strategies for autoimmunity. We have examined the transcriptional and functional consequences of reactivating memory CD4 T cells in the absence of an adjuvant. We find that memory CD4 T cells generated by infection or immunisation survive secondary activation with antigen delivered without adjuvant, regardless of their location in secondary lymphoid organs or peripheral tissues. These cells were, however, functionally altered following a tertiary immunisation with antigen and adjuvant, proliferating poorly but maintaining their ability to produce inflammatory cytokines. Transcriptional and cell cycle analysis of these memory CD4 T cells suggests they are unable to commit fully to cell division potentially because of low expression of DNA repair enzymes. In contrast, these memory CD4 T cells could proliferate following tertiary reactivation by viral re‐infection. These data indicate that antigen‐specific tolerogenic strategies must examine multiple parameters of Tcell function, and provide insight into the molecular mechanisms that may lead to deletional tolerance of memory CD4 T cells.

Cell therapies for autoimmune diseases using tolerogenic dendritic cells (tolDC) have been promisingly explored. A major stumbling block has been generating stable tolDC, with low risk of converting to mature immunogenic DC (mDC), exacerbating disease. mDC induction involves a metabolic shift to lactate production from oxidative phosphorylation (OXPHOS) and β-oxidation, the homeostatic energy source for resting DC. Inhibition of glycolysis through the administration of 2-deoxy glucose (2-DG) has been shown to prevent autoimmune disease experimentally but is not clinically feasible. We show here that treatment of mouse bone marrow-derived tolDC ex vivo with low-dose 2-DG (2.5 mM) (2-DGtolDC) induces a stable tolerogenic phenotype demonstrated by their failure to engage lactate production when challenged with mycobacterial antigen (Mtb). ~ 15% of 2-DGtolDC express low levels of MHC class II and 30% express CD86, while they are negative for CD40. 2-DGtolDC also express increased immune checkpoint molecules PDL-1 and SIRP-1α. Antigen-specific T cell proliferation is reduced in response to 2-DGtolDC in vitro. Mtb-stimulated 2-DGtolDC do not engage aerobic glycolysis but respond to challenge via increased OXPHOS. They also have decreased levels of p65 phosphorylation, with increased phosphorylation of the non-canonical p100 pathway. A stable tolDC phenotype is associated with sustained SIRP-1α phosphorylation and p85-AKT and PI3K signalling inhibition. Further, 2-DGtolDC preferentially secrete IL-10 rather than IL-12 upon Mtb-stimulation. Importantly, a single subcutaneous administration of 2-DGtolDC prevented experimental autoimmune uveoretinitis (EAU) in vivo. Inhibiting glycolysis of autologous tolDC prior to transfer may be a useful approach to providing stable tolDC therapy for autoimmune/immune-mediated diseases. Electronic supplementary material The online version of this article (10.1007/s00018-020-03672-y) contains supplementary material, which is available to authorized users.

Variation in intraspecific traits is one important mechanism that can allow plant species to respond to global changes. Understanding plant trait responses to environmental changes such as grazing patterns, nutrient enrichment and climate warming is, thus, essential for predicting the composition of future plant communities. We measured traits of eight common tundra species in a fully factorial field experiment with mammalian herbivore exclusion, fertilization, and passive warming, and assessed how trait responsiveness to the treatments was associated with abundance changes in those treatments. Herbivory exhibited the strongest impact on traits. Exclusion of herbivores increased vegetative plant height by 50% and specific leaf area (SLA) by 19%, and decreased foliar C:N by 11%; fertilization and warming also increased height and SLA but to a smaller extent. Herbivory also modulated intraspecific height, SLA and foliar C:N responses to fertilization and warming, and these interactions were species-specific. Furthermore, herbivory affected how trait change translated into relative abundance change: increased height under warming and fertilization was more positively related to abundance change inside fences than in grazed plots. Our findings highlight the key role of mammalian herbivory when assessing intraspecific trait change in tundra and its consequences for plant performance under global changes.

ObjectiveThiopurines are widely used as maintenance therapy in inflammatory bowel disease (IBD) but the evidence base for their use is sparse and their role increasingly questioned. Using the largest series reported to date, we assessed the long-term effectiveness of thiopurines in ulcerative colitis (UC) and Crohn’s disease (CD), including their impact on need for surgery.DesignOutcomes were assessed in 11 928 patients (4968 UC, 6960 CD) in the UK IBD BioResource initiated on thiopurine monotherapy with the intention of maintaining medically induced remission. Effectiveness was assessed retrospectively using patient-level data and a definition that required avoidance of escalation to biological therapy or surgery while on thiopurines. Analyses included overall effectiveness, time-to-event analysis for treatment escalation and comparison of surgery rates in patients tolerant or intolerant of thiopurines.ResultsUsing 68 132 patient-years of exposure, thiopurine monotherapy appeared effective for the duration of treatment in 2617/4968 (52.7%) patients with UC compared with 2378/6960 (34.2%) patients with CD (pConclusionThiopurine monotherapy is an effective long-term treatment for UC but significantly less effective in CD.

Infections caused by Staphylococcus aureus are a leading cause of mortality. Treating infections caused by S. aureus is difficult due to resistance against most traditional antibiotics, including β-lactams. We previously reported the presence of mutations in gdpP among S. aureus strains that were obtained by serial passaging in β-lactam drugs. Similar mutations have recently been reported in natural S. aureus isolates that are either non-susceptible or resistant to β-lactam antibiotics. gdpP codes for a phosphodiesterase that cleaves cyclic-di-AMP (CDA), a newly discovered second messenger. In this study, we sought to identify the role of gdpP in β-lactam resistance in S. aureus. Our results showed that gdpP associated mutations caused loss of phosphodiesterase function, leading to increased CDA accumulation in the bacterial cytosol. Deletion of gdpP led to an enhanced ability of the bacteria to withstand a β-lactam challenge (two to three log increase in bacterial colony forming units) by promoting tolerance without enhancing MICs of β-lactam antibiotics. Our results demonstrated that increased drug tolerance due to loss of GdpP function can provide a selective advantage in acquisition of high-level β-lactam resistance. Loss of GdpP function thus increases tolerance to β-lactams that can lead to its therapy failure and can permit β-lactam resistance to occur more readily.

Physiological responses to both natural and anthropogenic perturbations involve changes in glucose use and metabolism to enable animals to respond to challenges. The responses are at least partially mediated via the glucocorticoids, and the proper functioning of these systems are critical to animal health. Prolonged high-sugar diets in humans can compromise physiological functions and lead to a range of diseases including diabetes. Such outcomes are less common in natural, non-human systems, likely because of evolutionarily based balances between sugar intake and the ability to process it. Due to both landscape changes and human feeding of wildlife, the introduction of unnatural diets to wildlife is becoming increasingly common. However, the implications of unnatural dietary changes, and in particular changes in dietary glucose, are not well understood in non-human systems. We tested the effects of a high glucose diet on glucose tolerance in a controlled setting using captive juvenile Green Iguanas (Iguana iguana). In the field, we similarly performed glucose challenges (i.e., glucose tolerance tests) on Northern Bahamian Rock Iguanas (Cyclura cychlura) that are either fed or unfed by tourists, and we evaluated both short (within 8 hrs) and longer-term (within 19 hrs) blood glucose responses as well as plasma corticosterone (CORT) concentrations. Overall, we found significant effects of both experimental glucose supplementation in the laboratory and tourist feeding in the wild on glucose metabolism. In all instances where iguanas received a glucose-rich diet, we found greater acute increases in blood glucose following a glucose challenge. In the wild, tourist-fed iguanas, relative to unfed iguanas, had significantly lower baseline CORT levels, higher baseline blood glucose levels, and slower returns to baseline glucose levels following a glucose challenge. Therefore, glucose intolerance in response to unnatural glucose consumption is manifesting in both laboratory animals with relatively short-term glucose treatment and free-living iguanas exposed to long-term supplemental feeding by tourists. We also found more rapid increases in CORT response to capture and processing in tourist-fed iguanas and that CORT was positively related to blood glucose one-hour post glucose challenge, but only in tourist exposed and fed iguanas. Based on these results and the increasing prevalence of wildlife feeding on unnatural diets, further research is needed to understand how dietary changes affect glucose metabolism broadly across species and whether such changes cause any health ramifications.

Although the global pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still ongoing, there are currently no specific and highly efficient drugs for COVID-19 available, particularly in severe cases. Recent findings demonstrate that severe COVID-19 disease that requires hospitalization is associated with the hyperactivation of CD4+ and CD8+ T cell subsets. In this study, we aimed to counteract this high inflammatory state by inducing T-cell hyporesponsiveness in a SARS-CoV-2-specific manner using tolerogenic dendritic cells (tolDC). In vitro-activated SARS-CoV-2-specific T cells were isolated and stimulated with SARS-CoV-2 peptide-loaded monocyte-derived tolDC or with SARS-CoV-2 peptide-loaded conventional (conv) DC. We demonstrate a significant decrease in the number of interferon (IFN)-γ spot-forming cells when SARS-CoV-2-specific T cells were stimulated with tolDC as compared to stimulation with convDC. Importantly, this IFN-γ downmodulation in SARS-CoV-2-specific T cells was antigen-specific, since T cells retain their capacity to respond to an unrelated antigen and are not mediated by T cell deletion. Altogether, we have demonstrated that SARS-CoV-2 peptide-pulsed tolDC induces SARS-CoV-2-specific T cell hyporesponsiveness in an antigen-specific manner as compared to stimulation with SARS-CoV-2-specific convDC. These observations underline the clinical potential of tolDC to correct the immunological imbalance in the critically ill.