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1.
Heliyon ; 10(7): e28407, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560212

RESUMO

Viability loss of probiotics often occur during processing, storage and gastrointestinal transit. In this study, the viability of freeze-dried Lactobacillus acidophilus LA-5® was assessed after controlled freeze drying and storage at 4 °C and 25 °C over six months using glycerol, skim milk and trehalose as protectants. The freeze-dried probiotic was filled into hard gelatin capsules and enteric coated with the co-polymer Eudragit L100-55 using a fluidised bed coater to determine if the freeze-dried probiotic will survive the enteric coating process and remain viable during gastric transit. Empty hard gelatin capsules were also enteric coated by dipping in the co-polymer solution. These were dried, filled with microcrystalline cellulose and tested for their resistance to simulated gastric condition. The results showed that controlled freezing of the probiotic bacteria did not cause significant loss in viability when the cells were cryopreserved in the protectants. Viable cell loss was greater during the drying stage. Relatively better cell survival was recorded when the freeze-dried samples that were cryopreserved with skim milk were stored over six months at 4 °C. Freeze-dried samples that were preserved with trehalose stored better at 25 °C. The results also demonstrated that capsules coated with Eudragit L100-55 did not disintegrate in simulated gastric fluid. However, the capsules disintegrated in a simulated intestinal fluid. The enteric coating process resulted in about 95% recovery of viable cells. The high viable cell recovery after the coating process is likely due to the coating solution and conditions impacting the capsule body and cap rather than the cells directly. The study highlights that enteric coated capsules can offer gastric protection whilst minimizing viability losses associated with the enteric coating process.

2.
Front Psychiatry ; 15: 1351116, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38563027

RESUMO

Introduction: Previous studies have demonstrated a strong link between perceived stress and binge eating behavior, but the psychological mechanisms underlying such phenomenon are not fully understood. The present study further addressed this issue in a life history framework, focusing on life history strategy and distress tolerance. Methods: Firstly, we investigated the mediation role of life history strategy on the relationship between perceived stress and binge eating behavior. Secondly, we examined the moderation role of distress tolerance on the effect of perceived stress on life history strategy, as well as on the direct effect of perceived stress on binge eating behavior. We analyzed data from 1342 Chinese university students. Results: Results indicated that life history strategy mediates the relationship between perceived stress and binge eating behavior; distress tolerance has significant moderating effects on the direct effect of perceived stress on binge eating behavior and their indirect effect via life history strategy. Discussion: Therefore, distress tolerance skills training and life history-based interventions might be potentially effective ways to reduce binge eating behavior triggered by perceived stress.

3.
mBio ; : e0321123, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564693

RESUMO

Most arthropod-borne viruses produce intermittent epidemics in infected plants. However, the underlying mechanisms of these epidemics are unclear. Here, we demonstrated that rice stripe mosaic virus (RSMV), a viral pathogen, significantly increases the mortality of its overwintering vector, the leafhopper species Recilia dorsalis. Cold-stress assays indicated that RSMV reduces the cold tolerance of leafhoppers, a process associated with the downregulation of leafhopper cuticular protein genes. An RSMV-derived small RNA (vsiR-t00355379) was found to facilitate the downregulation of a leafhopper endocuticle gene that is mainly expressed in the abdomen (named RdABD-5) and is conserved across dipteran species. The downregulation of RdABD-5 expression in R. dorsalis resulted in fewer and thinner endocuticle lamellae, leading to decreased cold tolerance. This effect was correlated with a reduced incidence rate of RSMV in early-planted rice plants. These findings contribute to our understanding of the mechanism by which viral pathogens reduce cold tolerance in arthropod vectors and suggest an approach to managing the fluctuating prevalence of arboviruses. IMPORTANCE: Increasing arthropod vector dispersal rates have increased the susceptibility of crop to epidemic viral diseases. However, the incidence of some viral diseases fluctuates annually. In this study, we demonstrated that a rice virus reduces the cold tolerance of its leafhopper vector, Recilia dorsalis. This effect is linked to the virus-derived small RNA-mediated downregulation of a gene encoding a leafhopper abdominal endocuticle protein. Consequently, the altered structural composition of the abdominal endocuticle reduces the overwinter survival of leafhoppers, resulting in a lower incidence of RSMV infection in early-planted rice plants. Our findings illustrate the important roles of RNA interference in virus-vector insect-environment interactions and help explain the annual fluctuations of viral disease epidemics in rice fields.

4.
Plant Cell Environ ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567814

RESUMO

Phosphorus (P)-hyperaccumulators for phytoextraction from P-polluted areas generally show rapid growth and accumulate large amounts of P without any toxicity symptom, which depends on a range of physiological processes and gene expression patterns that have never been explored. We investigated growth, leaf element concentrations, P fractions, photosynthetic traits, and leaf metabolome and transcriptome response in amphibious P-hyperaccumulators, Polygonum hydropiper and P. lapathifolium, to high-P exposure (5 mmol L-1), with 0.05 mmol L-1 as the control. Under high-P exposure, both species demonstrated good growth, allocating more P to metabolite P and inorganic P (Pi) accompanied by high potassium and calcium. The expression of a cluster of unigenes associated with photosynthesis was maintained or increased in P. lapathifolium, explaining the increase in net photosynthetic rate and the rapid growth under high-P exposure. Metabolites of trehalose metabolism, including trehalose 6-phosphate and trehalose, were sharply increased in both species by the high-P exposure, in line with the enhanced expression of associated unigenes, indicating that trehalose metabolic pathway was closely related to high-P tolerance. These findings elucidated the physiological and molecular responses involved in the photosynthesis and trehalose metabolism in P-hyperaccumulators to high-P exposure, and provides potential regulatory pathways to improve the P-phytoextraction capability.

5.
Plant Commun ; : 100891, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561965

RESUMO

Plants grown under extreme environments represent unique sources for stress-resistant genes and mechanisms. Ammopiptanthus mongolicus (Leguminosae) is a xerophytic legume shrub with evergreen broadleaves native to the semi-arid and desert regions, however, its drought tolerance mechanisms have not been well understood. Here, we report the assembly of a reference-grade genome, its evolutionary history within the legume family, and examination to its drought tolerance mechanisms. The assembled genome size was 843.07 Mb and 98.7% of the assembly was successfully anchored to the nine chromosomes of the plant. 47,611 genes were predicted to be protein-coding and 70.71% of the genome is composed of repetitive sequences dominated by transposable elements, particularly long-terminal-repeat retrotransposons (LTR-RTs). Evolutionary analyses revealed two whole-genome duplication (WGD) events shared by the genus Ammopiptanthus and other legumes at 130 and 58 million years ago (Mya), whereas no species-specific WGD was found within this genus. Further ancestral genome reconstruction indicated that the A. mongolicus genome had fewer rearrangements within the legume family, confirming it is a "relict plant". Transcriptomic analyses revealed that cuticular wax biosynthesis and transport genes were highly expressed under both normal and polyethylene glycol (PEG)-induced dehydration conditions, and significant induction of ethylene biosynthesis and signaling related genes was also observed in leaves experiencing the dehydration stress, indicating that enhanced ethylene response and formation of thick waxy cuticles are two major mechanisms of drought tolerance in A. mongolicus. Consistently, ectopic expression of AmERF2, an ethylene response factor unique for A. mongolicus, resulted in marked increase of drought tolerance in transgenic Arabidopsis thaliana plants, demonstrating the application potential of A. mongolicus genes in crop improvement.

6.
Nanomicro Lett ; 16(1): 167, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564086

RESUMO

Microwave absorbing materials (MAMs) characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical applications. Both silicon carbide and carbon are considered as stable MAMs under some rigorous conditions, while their composites still fail to produce satisfactory microwave absorption performance regardless of the improvements as compared with the individuals. Herein, we have successfully implemented compositional and structural engineering to fabricate hollow SiC/C microspheres with controllable composition. The simultaneous modulation on dielectric properties and impedance matching can be easily achieved as the change in the composition of these composites. The formation of hollow structure not only favors lightweight feature, but also generates considerable contribution to microwave attenuation capacity. With the synergistic effect of composition and structure, the optimized SiC/C composite exhibits excellent performance, whose the strongest reflection loss intensity and broadest effective absorption reach - 60.8 dB and 5.1 GHz, respectively, and its microwave absorption properties are actually superior to those of most SiC/C composites in previous studies. In addition, the stability tests of microwave absorption capacity after exposure to harsh conditions and Radar Cross Section simulation data demonstrate that hollow SiC/C microspheres from compositional and structural optimization have a bright prospect in practical applications.

7.
Plant Signal Behav ; 19(1): 2331357, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38564424

RESUMO

Ornamental crops particularly cut flowers are considered sensitive to heavy metals (HMs) induced oxidative stress condition. Melatonin (MLT) is a versatile phytohormone with the ability to mitigate abiotic stresses induced oxidative stress in plants. Similarly, signaling molecules such as hydrogen sulfide (H2S) have emerged as potential options for resolving HMs related problems in plants. The mechanisms underlying the combined application of MLT and H2S are not yet explored. Therefore, we evaluated the ability of individual and combined applications of MLT (100 µM) and H2S in the form of sodium hydrosulfide (NaHS), a donor of H2S, (1.5 mM) to alleviate cadmium (Cd) stress (50 mg L-1) in stock (Matthiola incana L.) plants by measuring various morpho-physiological and biochemical characteristics. The results depicted that Cd-stress inhibited growth, photosynthesis and induced Cd-associated oxidative stress as depicted by excessive ROS accumulation. Combined application of MLT and H2S efficiently recovered all these attributes. Furthermore, Cd stress-induced oxidative stress markers including electrolyte leakage, malondialdehyde, and hydrogen peroxide are partially reversed in Cd-stressed plants by MLT and H2S application. This might be attributed to MLT or H2S induced antioxidant plant defense activities, which effectively reduce the severity of oxidative stress indicators. Overall, MLT and H2S supplementation, favorably regulated Cd tolerance in stock; yet, the combined use had a greater effect on Cd tolerance than the independent application.


Assuntos
Brassicaceae , Sulfeto de Hidrogênio , Melatonina , Sulfetos , Sulfeto de Hidrogênio/farmacologia , Cádmio/toxicidade , Melatonina/farmacologia , Estresse Oxidativo , Antioxidantes/metabolismo , Brassicaceae/metabolismo , Peróxido de Hidrogênio
8.
Int J Biol Macromol ; 266(Pt 2): 131293, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565368

RESUMO

The major latex proteins/ripening-related proteins are a subfamily of the Bet v 1 protein superfamily and are commonly involved in plant development and responses to various stresses. However, the functions of MLPs in the postharvest cold storage of fruits remain uninvestigated. Herein, we identified 30 MLP genes in the peach (Prunus persica) genome that were clustered into three subgroups. Chromosomal location analysis revealed that the PpMLP genes were unevenly distributed on five of the eight peach chromosomes. Synteny analysis of the MLP genes between peach and seven other plant species (five dicotyledons and two monocotyledons) explored their evolutionary characteristics. Furthermore, the PpMLP promoters contained cis-elements for multiple hormones and stress responses. Gene expression analysis revealed that PpMLPs participated in chilling stress responses. Ectopic expression of PpMLP10 in Arabidopsis improved chilling stress tolerance by decreasing membrane damage and maintaining membrane stability. Additional research confirmed that PpWRKY2 participates in PpMLP10-mediated chilling stress by binding to its promoter. Collectively, these results suggest the role of PpMLP10 in enhancing chilling stress tolerance, which is significant for decreasing chilling injury during the postharvest cold storage of peaches.

9.
Front Plant Sci ; 15: 1349401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38571718

RESUMO

Climate change poses a major threat to global food security, significantly reducing crop yields as cause of abiotic stresses, and for boosting the spread of new and old pathogens and pests. Sustainable crop management as a route to mitigation poses the challenge of recruiting an array of solutions and tools for the new aims. Among these, the deployment of positive interactions between the micro-biotic components of agroecosystems and plants can play a highly significant role, as part of the agro-ecological revolution. Endophytic microorganisms have emerged as a promising solution to tackle this challenge. Among these, Arbuscular Mycorrhizal Fungi (AMF) and endophytic bacteria and fungi have demonstrated their potential to alleviate abiotic stresses such as drought and heat stress, as well as the impacts of biotic stresses. They can enhance crop yields in a sustainable way also by other mechanisms, such as improving the nutrient uptake, or by direct effects on plant physiology. In this review we summarize and update on the main types of endophytes, we highlight several studies that demonstrate their efficacy in improving sustainable yields and explore possible avenues for implementing crop-microbiota interactions. The mechanisms underlying these interactions are highly complex and require a comprehensive understanding. For this reason, omic technologies such as genomics, transcriptomics, proteomics, and metabolomics have been employed to unravel, by a higher level of information, the complex network of interactions between plants and microorganisms. Therefore, we also discuss the various omic approaches and techniques that have been used so far to study plant-endophyte interactions.

10.
Glob Chang Biol ; 30(4): e17249, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572713

RESUMO

Warming as well as species introductions have increased over the past centuries, however a link between cause and effect of these two phenomena is still unclear. Here we use distribution records (1813-2023) to reconstruct the invasion histories of marine non-native macrophytes, macroalgae and seagrasses, in the Mediterranean Sea. We defined expansion as the maximum linear rate of spread (km year-1) and the accumulation of occupied grid cells (50 km2) over time and analyzed the relation between expansion rates and the species' thermal conditions at its native distribution range. Our database revealed a marked increase in the introductions and spread rates of non-native macrophytes in the Mediterranean Sea since the 1960s, notably intensifying after the 1990s. During the beginning of this century species velocity of invasion has increased to 26 ± 9 km2 year-1, with an acceleration in the velocity of invasion of tropical/subtropical species, exceeding those of temperate and cosmopolitan macrophytes. The highest spread rates since then were observed in macrophytes coming from native regions with minimum SSTs two to three degrees warmer than in the Mediterranean Sea. In addition, most non-native macrophytes in the Mediterranean (>80%) do not exceed the maximum temperature of their range of origin, whereas approximately half of the species are exposed to lower minimum SST in the Mediterranean than in their native range. This indicates that tropical/subtropical macrophytes might be able to expand as they are not limited by the colder Mediterranean SST due to the plasticity of their lower thermal limit. These results suggest that future warming will increase the thermal habitat available for thermophilic species in the Mediterranean Sea and continue to favor their expansion.


Assuntos
Espécies Introduzidas , Alga Marinha , Mar Mediterrâneo , Ecossistema , Temperatura
11.
Artigo em Inglês | MEDLINE | ID: mdl-38573102

RESUMO

A novel Gram-positive strain, B1T, was isolated from uranium-contaminated soil. The strain was aerobic, rod-shaped, spore-forming, and motile. The strain was able to grow at 20-45 °C, at pH 6.0-9.0, and in the presence of 0-3 % (w/v) NaCl. The complete genome size of the novel strain was 3 853 322 bp. The genomic DNA G+C content was 45.5 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain B1T has the highest similarity to Aneurinibacillus soli CB4T (96. 71 %). However, the novel strain showed an average nucleotide identity value of 89.02 % and a digital DNA-DNA hybridization value of 37.40 % with strain CB4T based on the genome sequences. The major fatty acids were iso-C15 : 0 and C16 : 0. The predominate respiratory quinone was MK7. Diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipids, an unidentified aminolipid and an unidentified lipid were identified as the major polar lipids. The phylogenetic, phenotypic, and chemotaxonomic analyses showed that strain B1T represents a novel species of the genus Aneurinibacillus, for which the name Aneurinibacillus uraniidurans sp. nov. is proposed. The type strain is B1T (=GDMCC 1.4080T=JCM 36228T). Experiments have shown that strain B1T demonstrates uranium tolerance.


Assuntos
Ácidos Graxos , Urânio , Composição de Bases , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias , Solo
12.
Environ Entomol ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38574195

RESUMO

Eastern subterranean termites, Reticulitermes flavipes (Kollar), are widely distributed across North America where they are exposed to a broad range of environmental conditions. However, mechanisms for overwintering are not well understood. Wisconsin is a unique location to study mechanisms of cold tolerance as it represents the northern boundary for persistent R. flavipes populations. In this study, we evaluated seasonal shifts in cold tolerance using critical thermal minimum (CTmin) and supercooling point (SCP) and examined how these measurements correlate to changes in the microbial community of the termite gut. Results showed seasonal acclimatization to cold, which is consistent with the use of behavioral freeze-avoidant mechanisms. However, these insects also demonstrated an increased susceptibility to freezing later in the season, which may be tied to changes in gut microbiota. Our results found shifts in the composition of the gut microbiome in R. flavipes between mid- to late summer and early to late fall. These differences may be suggestive of a change in metabolism to adjust to a period of reduced feeding and increased metabolic stress during overwintering. Specifically, results showed an increased abundance of Methanobrevibacter sp. (Euryarchaeota) associated with cold, which may be indicative of a metabolic shift from acetogenesis to methanogenesis associated with overwintering. Further work is needed focusing on specific contributions of certain gut microbes, particularly their role in metabolic adaptability and in providing protection from oxidative stress associated with changes in environmental conditions.

13.
Int Immunol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38576231

RESUMO

Autoimmune diseases often arise from conditions where the immune system is compromised. While lymphopenia-induced proliferation (LIP) is crucial for immune system development and maturation, it is also caused by environmental insult, such as infection and becomes a risk factor for autoimmunity in adults. We used Dsg3H1 TCR Transgenic mice, whose T cells are designed to recognize desmogrein-3, a skin antigen, to explore the impact of lymphopenia on post-thymic tolerance. Dsg3H1 mice are known to delete the most highly autoreactive T cells in thymus, and develop only subtle immune-mediated pathology in a steady state. However, we found that a transient lymphopenia by total body irradiation or cyclophosphamide, results in massive dermatitis in Dsg3H1 mice. The symptoms included expansion and development of self-reactive T cells, their differentiation into CD44 high IL-17 producing helper T cells, and severe neutrophilic inflammation. Repopulation of FOXP3+ T regulatory cells after lymphopenia normally occurred, suggesting escape of skin-reactive conventional T cells from control by regulatory T cell. Furthermore, we found that a depletion of the intestinal microbiota by antibiotics prevents the cyclophosphamide induced dermatitis, indicating roles of commensal intestinal microbiota in LIP and Th17 development in vivo. The current data suggested that post thymic tolerance of Dsg3H1 mice is established on a fragile balance in lymphoreplete immune environment and broken by interplay between lymphopenia and intestinal microbiota. The dynamic phenotypes observed in Dsg3H1 mice prompts a reevaluation of opportunistic lymphopenia together with microbiota as pivotal environmental factors, impacting individuals with genetic predispositions of autoimmune diseases.

14.
Brain ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577773

RESUMO

Opioid pain medications, such as morphine, remain the mainstay for treating severe and chronic pain. Prolonged morphine use, however, triggers analgesic tolerance and hyperalgesia (OIH), which can last for a long period after morphine withdrawal. How morphine induces these detrimental side effects remains unclear. Here, we show that morphine tolerance and OIH are mediated by Tiam1-coordinated synaptic structural and functional plasticity in the spinal nociceptive network. Tiam1 is a Rac1 GTPase guanine nucleotide exchange factor (GEF) that promotes excitatory synaptogenesis by modulating actin cytoskeletal dynamics. We found that prolonged morphine treatment activated Tiam1 in the spinal dorsal horn and Tiam1 ablation from spinal neurons eliminated morphine antinociceptive tolerance and OIH. At the same time, the pharmacological blockade of Tiam1-Rac1 signaling prevented the development and reserved the established tolerance and OIH. Prolonged morphine treatment increased dendritic spine density and synaptic NMDA receptor (NMDAR) activity in spinal dorsal horn neurons, both of which required Tiam1. Furthermore, co-administration of the Tiam1 signaling inhibitor NSC23766 was sufficient to abrogate morphine tolerance in chronic pain management. These findings identify Tiam1-mediated maladaptive plasticity in the spinal nociceptive network as an underlying cause for the development and maintenance of morphine tolerance and OIH and provide a promising therapeutic target to reduce tolerance and prolong morphine use in chronic pain management.

15.
Conserv Biol ; : e14266, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578127

RESUMO

Survival of the immobile embryo in response to rising temperature is important to determine a species' vulnerability to climate change. However, the collective effects of 2 key thermal characteristics associated with climate change (i.e., rising average temperature and acute heat events) on embryonic survival remain largely unexplored. We used empirical measurements and niche modeling to investigate how chronic and acute heat stress independently and collectively influence the embryonic survival of lizards across latitudes. We collected and bred lizards from 5 latitudes and incubated their eggs across a range of temperatures to quantify population-specific responses to chronic and acute heat stress. Using an embryonic development model parameterized with measured embryonic heat tolerances, we further identified a collective impact of embryonic chronic and acute heat tolerances on embryonic survival. We also incorporated embryonic chronic and acute heat tolerance in hybrid species distribution models to determine species' range shifts under climate change. Embryos' tolerance of chronic heat (T-chronic) remained consistent across latitudes, whereas their tolerance of acute heat (T-acute) was higher at high latitudes than at low latitudes. Tolerance of acute heat exerted a more pronounced influence than tolerance of chronic heat. In species distribution models, climate change led to the most significant habitat loss for each population and species in its low-latitude distribution. Consequently, habitat for populations across all latitudes will shift toward high latitudes. Our study also highlights the importance of considering embryonic survival under chronic and acute heat stresses to predict species' vulnerability to climate change.


Efectos colectivos del aumento de las temperaturas promedio y los eventos de calor en embriones ovíparos Resumen La supervivencia de los embriones inmóviles en respuesta al incremento de temperatura es importante para determinar la vulnerabilidad de las especies al cambio climático. Sin embargo, los efectos colectivos de dos características térmicas claves asociadas con el cambio climático (i. e., aumento de temperatura promedio y eventos de calor agudo) sobre la supervivencia embrionaria permanecen en gran parte inexplorados. Utilizamos mediciones empíricas y modelos de nicho para investigar cómo el estrés térmico crónico y agudo influye de forma independiente y colectiva en la supervivencia embrionaria de los lagartos en todas las latitudes. Recolectamos y criamos lagartos de cinco latitudes e incubamos sus huevos en un rango de temperaturas para cuantificar las respuestas específicas de la población al estrés por calor crónico y agudo. Posteriormente, mediante un modelo de desarrollo embrionario parametrizado con mediciones de tolerancia embrionaria al calor, identificamos un impacto colectivo de las tolerancias embrionarias al calor agudo y crónico en la supervivencia embrionaria. También incorporamos la tolerancia embrionaria crónica y aguda al calor en modelos de distribución de especies híbridas para determinar los cambios de distribución de las especies bajo el cambio climático. La tolerancia embrionaria al calor crónico (T­crónico) permaneció constante, mientras que la tolerancia al calor agudo (T­agudo) fue mayor en latitudes altas que en latitudes bajas. La tolerancia al calor agudo ejerció una influencia más pronunciada que la tolerancia al calor crónico. En los modelos de distribución de especies, el cambio climático provocó la pérdida de hábitat más significativa para cada población y especie en su distribución de latitudes bajas. En consecuencia, el hábitat para poblaciones en todas las latitudes se desplazará a latitudes altas. Nuestro estudio también resalta la importancia de considerar la supervivencia embrionaria bajo estrés térmico crónico y agudo para predecir la vulnerabilidad de las especies al cambio climático.

16.
J Integr Plant Biol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578160

RESUMO

Structural variations (SVs) are a feature of plant genomes that has been largely unexplored despite their significant impact on plant phenotypic traits and local adaptation to abiotic and biotic stress. In this study, we employed woolly grape (Vitis retordii), a species native to the tropical and subtropical regions of East Asia with both coastal and inland habitats, as a valuable model for examining the impact of SVs on local adaptation. We assembled a haplotype-resolved chromosomal reference genome for woolly grape, and conducted population genetic analyses based on whole-genome sequencing (WGS) data from coastal and inland populations. The demographic analyses revealed recent bottlenecks in all populations and asymmetric gene flow from the inland to the coastal population. In total, 1,035 genes associated with plant adaptive regulation for salt stress, radiation, and environmental adaptation were detected underlying local selection by SVs and SNPs in the coastal population, of which 37.29% and 65.26% were detected by SVs and SNPs, respectively. Candidate genes such as FSD2, RGA1, and AAP8 associated with salt tolerance were found to be highly differentiated and selected during the process of local adaptation to coastal habitats in SV regions. Our study highlights the importance of SVs in local adaptation; candidate genes related to salt stress and climatic adaptation to tropical and subtropical environments are important genomic resources for future breeding programs of grapevine and its rootstocks.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38598749

RESUMO

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by abnormal activation of CD4+ T cells and an imbalance of T helper 17 (Th17) and regulatory T (Treg) cells. Tolerogenic therapy via administration of self-antigens is a promising strategy for RA treatment, but delivery of autoantigens alone may exacerbate disease conditions. Current studies indicated that codelivery of autoantigens with immunomodulators can lead to a more tolerogenic immune response. Here, we constructed an autoantigen type II collagen peptide (CII250-270)- and immunomodulator leflunomide (LEF)-coloaded phosphatidylserine liposome vaccine (CII250-270-LEF-PSL) for RA treatment via induction of tolerant dendritic cells (tolDC) for further activation of Treg cells. The in vivo results showed that CII250-270-LEF-PSL can effectively induce tolDC, regulate the balance of Th1/Th2 and Th17/Treg, and reduce the secretion of pro-inflammatory cytokines (IFN-γ, IL-1ß, and IL-17A) and IgG antibodies to inhibit synovial inflammation and bone erosion. Furthermore, our study also suggested that LEF regulated Th1 cell differentiation by inhibiting the activation of the JAK1/STAT1 signaling pathway, further alleviating RA. Overall, this work proved that the combination of autoantigenic peptides and immunomodulators was a promising modality for RA treatment by reestablishing antigen-specific immune tolerance, which also inspired additional insights into the development of combination therapies for the tolerability of RA.

18.
Adv Mater ; : e2401236, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599344

RESUMO

Common polymeric conductive electrodes, such as polyethylene terephthalate (PET) coated with indium tin oxide, face a major challenge of their low processing-temperature limits, attributed to PET's low glass transition temperature (Tg of 70-80 °C). This limitation significantly narrows the scope of material selection, limits the processing techniques applicable to the low Tg, and hinders the ripened technology transfer from glass substrates to them. Addressing the temperature constraints of the flexible substrates is impactful yet underexplored, with broader implications for fields beyond photovoltaics. Here we introduce a new thermal radiation annealing methodology to address this issue. By applying above Tg radiation annealing in conjunction with thermoelectric cooling, we successfully create highly ordered molecular packing on PET substrates, which are exclusively unachievable due to PET's low thermal tolerance. As a result, in the context of perovskite solar cells, this approach enables the circumvention of high-temperature annealing limitations of PET substrates, leading to a remarkable flexible device efficiency of 22.61% and a record fill factor of 83.42%. This approach proves especially advantageous for advancing the field of flexible optoelectronic devices. This article is protected by copyright. All rights reserved.

19.
J Fish Biol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599790

RESUMO

Animals routinely encounter environmental (e.g., high temperatures and hypoxia) as well as physiological perturbations (e.g., exercise and digestion) that may threaten homeostasis. However, comparing the relative threat or "disruptiveness" imposed by different stressors is difficult, as stressors vary in their mechanisms, effects, and timescales. We exploited the fact that several acute stressors can induce the loss of equilibrium (LOE) in fish to (i) compare the metabolic recovery profiles of three environmentally relevant stressors and (ii) test the concept that LOE could be used as a physiological calibration for the intensity of different stressors. We focused on Etheostoma caeruleum, a species that routinely copes with environmental fluctuations in temperature and oxygen and that relies on burst swimming to relocate and avoid predators, as our model. Using stop-flow (intermittent) respirometry, we tracked the oxygen consumption rate (MO2) as E. caeruleum recovered from LOE induced by hypoxia (PO2 at LOE), warming (critical thermal maximum, CTmax), or exhaustive exercise. Regardless of the stressor used, E. caeruleum recovered rapidly, returning to routine MO2 within ~3 h. Fish recovering from hypoxia and warming had similar maximum MO2, aerobic scopes, recovery time, and total excess post-hypoxia or post-warming oxygen consumption. Though exhaustive exercise induced a greater maximum MO2 and corresponding higher aerobic scope than warming or hypoxia, its recovery profile was otherwise similar to the other stressors, suggesting that "calibration" to a physiological state such as LOE may be a viable conceptual approach for investigators interested in questions related to multiple stressors, cross tolerance, and how animals cope with challenges to homeostasis.

20.
Allergol Int ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38600019

RESUMO

BACKGROUND: Intestinal bacteria may play a role in the development of food allergies. This study aimed to analyze and compare the gut microbiota of food-allergic children with that of healthy children of the same age. METHODS: Stool samples were collected from one-and-a-half-year-old food-allergic (FA group, n = 29) and healthy controls (HC group, n = 19). A questionnaire was provided to examine the children's birth, dietary, medical, and social histories. The gut microbiota was profiled by 16S rRNA sequencing. Differences in taxonomic composition were assessed using linear discriminant analysis effect size (LEfSe), and microbial functional profiles were predicted with Tax4Fun2. RESULTS: No significant difference in the alpha diversity index between the two groups; however, a negative correlation was observed between the Shannon diversity index and the relative abundance of Bacteroides. A significant difference was observed in beta diversity (permutational multivariate analysis of variance) in the bacterial composition between the FA and HC groups (P < 0.05). The FA group had a higher abundance of Escherichia and Anaeromassilibacillus and a lower abundance of Bacteroides, Oscillibacter, Ruminococcus, Hungateiclostridium and Anaerotaenia than the HC group (LEfSe: linear discriminant analysis score >2). The FA group showed a predicted increase in the expression levels of genes associated with intestinal pathogenicity compared with that in the HC group. CONCLUSIONS: The gut microbiota of food-allergic children has a higher abundance of bacteria involved in intestinal inflammation and a lower abundance of bacteria involved in immune tolerance than that of healthy children. This dysbiosis may also be associated with food allergies.

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