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1.
Small Methods ; : e2400932, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39359025

RESUMO

Bacteriophage contamination has a devastating impact on the viability of bacterial hosts and can significantly reduce the productivity of bioprocesses in biotechnological industries. The consequences range from widespread fermentation failure to substantial economic losses, highlighting the urgent need for effective countermeasures. Conventional prevention methods, which focus primarily on the physical removal of bacteriophages from equipment, bioprocess units, and the environment, have proven ineffective in preventing phage entry and contamination. The coevolutionary dynamics between phages and their bacterial hosts have spurred the development of a diverse repertoire of antiviral defense mechanisms within microbial communities. These naturally occurring defense strategies can be harnessed through genetic engineering to convert phage-sensitive hosts into robust, phage-resistant cell factories, providing a strategic approach to mitigate the threats posed by bacteriophages to industrial bacterial processes. In this review, an overview of the various defense strategies and immune systems that curb the propagation of bacteriophages and highlight their applications in fermentation bioprocesses to combat phage contamination is provided. Additionally, the tactics employed by phages to circumvent these defense strategies are also discussed, as preventing the emergence of phage escape mutants is a key component of effective contamination management.

2.
Int J Biol Macromol ; : 135859, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39307505

RESUMO

Catalase, an enzyme central to maintaining redox balance and combating oxidative stress in plants, has emerged as a key player in plant defense mechanisms and interactions with microbes. This review article provides a comprehensive analysis of catalase-associated immune responses in plant-microbe interactions. It underscores the importance of catalase in plant defense mechanisms, highlights its influence on plant susceptibility to pathogens, and discusses its implications for understanding plant immunity and host-microbe dynamics. This review contributes to the growing body of knowledge on catalase-mediated immune responses and offers insights that can aid in the development of strategies for improved plant health and disease resistance.

3.
Heliyon ; 10(16): e34674, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39224353

RESUMO

Given the increasing utilization of forest components in integration systems worldwide, coupled with the growing demand for food in regions facing water restrictions, this study aims to evaluate how physiological and biochemical parameters contribute to the diversification of adaptive mechanisms among native species and eucalyptus genotypes intercropped with soybean or corn. The native tree species Anadenanthera macrocarpa and Dipteryx alata, and the eucalyptus genotypes Urograndis I-144 and Urocam VM01, were grown in soybean and corn intercropping areas and evaluated in fall, winter, spring, and summer. The study evaluated morning water potential, chloroplast pigment concentration, gas exchange, cell damage, and antioxidant enzyme activity. Intercropped with soybean, development the of A. macrocarpa improved through instantaneous water use efficiency, energy use by the electron transport chain, chloroplast pigments, and catalase enzyme activity. On the other hand, A. macrocarpa when, intercropped with corn, despite increasing energy absorption by the reaction center, there is a need for non-photochemical dissipation and in the activity of the enzymes superoxide dismutase and ascorbate peroxidase in response to water and oxidative deficits. In D. alata, the physiological and biochemical responses were not influenced by intercropping but by seasons, with increased chloroplast pigments in fall and electron transport in summer. However, in corn intercropping, the dissipation of excess energy allowed leaf acclimatization. The I-144 and VM01 genotypes also showed no significant differences between intercrops. The results describe photosynthetic and biochemical challenges in the native species A. macrocarpa intercropped with corn, such as a greater need for enzymatic and non-enzymatic defense mechanisms in response to more negative water potential. In D. alata, the challenges are present in both intercrops due to improved mechanisms to protect the photosynthetic apparatus. The survival of the I-144 genotype may be inefficient in both intercrops under prolonged drought conditions, as it modifies the photosystem; in contrast, genotype VM01 was the most adapted to the system for using captured energy, reducing water loss and being resilient.

4.
Plant Physiol Biochem ; 216: 109113, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276673

RESUMO

In many regions, nitrogen (N) deficiency limits pepper cultivation, presenting significant cultivation challenges. This study investigates the impact of N deficiency and silicon (Si) supplementation on physiological responses and antioxidant modulation in pepper plants, focusing particularly on the homeostasis of carbon (C), nitrogen, and phosphorus (P), and their effects on growth and biomass production. Conducted in a factorial design, the experiment examined pepper plants under conditions of N sufficiency and deficiency, with and without Si supplementation (0.0 mM and 2.0 mM). Results showed that N deficiency sensitizes pepper plants, leading to increased electrolyte leakage (39.59%) and disrupted C, N, and P homeostasis. This disruption manifests as reductions in photosynthetic pigments (-64.53%), photochemical efficiency (-14.92%), and the synthesis of key metabolites such as total free amino acids (-86.97%), sucrose (-53.88%), and soluble sugars (-39.96%), ultimately impairing plant growth. However, Si supplementation was found to alleviate these stresses. It modulated the antioxidant system, enhanced the synthesis of ascorbic acid (+30.23), phenolic compounds (+33.19%), and flavonoids (+7.52%), and reduced cellular electrolyte leakage (-25.02%). Moreover, Si helped establish a new homeostasis of C, N, and P, optimizing photosynthetic and nutritional efficiency by improving the utilization of C (+17.46%) and N (+13.20%). These Si-induced modifications in plant physiology led to increased synthesis of amino acids (+362.20%), soluble sugars (+51.34%), and sucrose (77.42%), thereby supporting enhanced growth of pepper plants. These findings elucidate the multifaceted biological roles of Si in mitigating N deficiency effects, offering valuable insights for more sustainable horticultural practices.

5.
Phytomedicine ; 135: 156028, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39276685

RESUMO

BACKGROUND: Natural products (NPs) have long been recognized for their potential to modulate the immune system, offering a natural and holistic approach to enhancing immune function. In recent years, the immunomodulation effects of various natural products have attained significant attention. PURPOSE: This article provides an overview of the role of natural products in immunomodulation, exploring their mechanisms of action, common types of NPs with immunomodulation properties, clinical applications, as well as considerations for their safety and efficacy. METHODS: Extensive research has been conducted to compile important discoveries on the immunomodulatory properties of NPs through thorough searches of multiple databases such as PubMed, Science Direct, and Scopus up until January 2024. RESULTS: By decreasing the levels of Th2 cytokines and pro-inflammatory cytokines, the results suggested that NPs have the ability to modulate the immune system. Therefore, NPs alleviate inflammation in various disorders such as asthma and cancer. Furthermore, the observed increase in CD4 cells and IFN-É£/IL4 levels, along with an increased IFN-c/IL4 ratio, indicates a stimulatory effect of NPs on Th1 activity in various inflammatory conditions. Therefore, NPs regulate the immune system by inhibiting T-cells and decreasing the growth of young B-cell lymphoma cells. CONCLUSION: Reviewing studies indicated that NPs have the potential to serve as immunomodulatory candidates for treating disorders characterized by immune dysregulation. However, additional experimental and clinical studies are necessary before these agents can be implemented in clinical settings.

6.
Anxiety Stress Coping ; : 1-15, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39211985

RESUMO

OBJECTIVES: This study explored whether several subgroups of athletes representing distinct trajectories of intensity and direction of pleasant and unpleasant emotions (anger, anxiety, dejection, excitement, and happiness) could be shown to exist within the latent growth analysis (LCGA). A secondary objective was to examine whether athletes belonging to distinct trajectories of intensity and direction of emotions reported distinct scores of adaptive defense mechanisms (ADM) and maladaptive defense mechanisms (MDM). DESIGN: A longitudinal four-wave measurement design was used in the present study. METHOD: 380 athletes completed the sports emotion questionnaire direction across four measurement times and the defense style questionnaire at the beginning of the season. RESULTS: Results of LCGAs revealed several distinct emotional trajectories for each emotion intensity and emotion direction. Moreover, athletes belonging to distinct (adaptive or maladaptive) trajectories reported significantly different scores of ADM and MDM. Higher scores of ADM were reported by athletes belonging to adaptive trajectories of the direction of emotions. CONCLUSIONS: Sports psychologists should try to promote ADM and defensive flexibility to help athletes perceive their emotions as facilitative.

7.
Insects ; 15(8)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39194777

RESUMO

Plants communicate with insects and other organisms through the release of volatile organic compounds (VOCs). Using Boolean operators, we retrieved 1093 articles from the Web of Science and Scopus databases, selecting 406 for detailed analysis, with approximately 50% focusing on herbivore-induced plant volatiles (HIPVs). This review examines the roles of VOCs in direct and indirect plant defense mechanisms and their influence on complex communication networks within ecosystems. Our research reveals significant functions of VOCs in four principal areas: activating insect antennae, attracting adult insects, attracting female insects, and attracting natural enemies. Terpenoids like α-pinene and ß-myrcene significantly alter pest behavior by attracting natural enemies. ß-ocimene and ß-caryophyllene are crucial in regulating aboveground and belowground interactions. We emphasize the potential applications of VOCs in agriculture for developing novel pest control strategies and enhancing crop resilience. Additionally, we identify research gaps and propose new directions, stressing the importance of comparative studies across ecosystems and long-term observational research to better understand VOCs dynamics. In conclusion, we provide insights into the multifunctionality of VOCs in natural ecosystems, their potential for future research and applications, and their role in advancing sustainable agricultural and ecological practices, contributing to a deeper understanding of their mechanisms and ecological functions.

8.
Psychiatry Investig ; 21(6): 672-679, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38960445

RESUMO

OBJECTIVE: Borderline personality disorder (BPD) is known to share characteristics with a variety of personality disorders (PDs) and exhibits diverse patterns of defense mechanisms. To enhance our understanding of BPD, it's crucial to shift our focus from traditional categorical diagnostics to the dimensional traits shared with other PDs, as the borderline personality organization (BPO) model suggests. This approach illuminates the nuanced spectrum of BPD characteristics, offering deeper insights into its complexity. While studies have investigated the comorbidity of BPD with other PDs, research exploring the relationship between various personality factors and defense mechanisms within BPD itself has been scarce. The present study was undertaken to investigate the complex interrelationships between various personality factors and defense styles in individuals diagnosed with BPD. METHODS: Using a network analysis approach, data from 227 patients diagnosed with BPD were examined using the Defense Style Questionnaire and Personality Disorder Questionnaire-4+ for assessment. RESULTS: Intricate connections were observed between personality factors and defense styles. Significant associations were identified between various personality factors and defense styles, with immature defense styles, such as maladaptive and image-distorting being particularly prominent in BPD in the centrality analysis. The maladaptive defense style had the highest expected influence centrality. Furthermore, the schizotypal, dependent, and narcissistic personality factors demonstrated relatively high centrality within the network. CONCLUSION: Network analysis can effectively delineate the complexity of various PDs and defense styles. These findings are expected to facilitate a deeper understanding of why BPD exhibits various levels of organization and presents with heterogeneous characteristics, consistent with the perspectives proposed by the BPO.

9.
Plant Cell Rep ; 43(8): 197, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014054

RESUMO

Reactive oxygen species (ROS) play a complex role in interactions between plant viruses and their host plants. They can both help the plant defend against viral infection and support viral infection and spread. This review explores the various roles of ROS in plant-virus interactions, focusing on their involvement in symptom development and the activation of plant defense mechanisms. The article discusses how ROS can directly inhibit viral infection, as well as how they can regulate antiviral mechanisms through various pathways involving miRNAs, virus-derived small interfering RNAs, viral proteins, and host proteins. Additionally, it examines how ROS can enhance plant resistance by interacting with hormonal pathways and external substances. The review also considers how ROS might promote viral infection and transmission, emphasizing their intricate role in plant-virus dynamics. These insights offer valuable guidance for future research, such as exploring the manipulation of ROS-related gene expression through genetic engineering, developing biopesticides, and adjusting environmental conditions to improve plant resistance to viruses. This framework can advance research in plant disease resistance, agricultural practices, and disease control.


Assuntos
Resistência à Doença , Doenças das Plantas , Vírus de Plantas , Plantas , Espécies Reativas de Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Vírus de Plantas/fisiologia , Vírus de Plantas/patogenicidade , Doenças das Plantas/virologia , Resistência à Doença/genética , Plantas/virologia , Plantas/metabolismo , Interações Hospedeiro-Patógeno , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Front Psychol ; 15: 1432170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988381

RESUMO

The Defense Mechanisms Rating Scales-Self Report-30 (DMRS-SR-30) was recently developed to add a self-report alternative to the assessment of defenses, reflecting their generally accepted hierarchical organization. In this study, we aimed to examine psychometric properties and factor structure of the Turkish language version of the DMRS-SR-30. The sample consisted of 1.002 participants who filled out a survey comprising the DMRS-SR-30, the Brief Symptom Inventory, and the Inventory of Personality Organization through Qualtrics. Confirmatory Factor Analysis indicated a three-factor structure (CFI = 0.89, RMSEA = 0.05) that confirms the DMRS theoretical frame with a relatively acceptable fit. Defensive categories and total scale scores showed good to excellent reliability (α values ranging from 0.64 to 0.89). Correlations between defenses, symptoms, and personality functioning demonstrated good convergent and discriminant validity. The individuals with clinically significant BSI scores (T-score ≥ 63) differed on the DMRS-SR-30 scores from the individuals in the non-clinical range. The Turkish version of the DMRS-SR-30 is a reliable and valid instrument to self-assess the hierarchy of defense mechanisms and overall defensive functioning. Moreover, the current study supports the validity of the tripartite model of defenses in a language and culture different from the origins of the DMRS and DMRS-SR-30.

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