Trends in the Potential of Stilbenes to Improve Plant Stress Tolerance: Insights of Plant Defense Mechanisms in Response to Biotic and Abiotic Stressors.

Stilbenes belong to the naturally synthesized plant phytoalexins, produced de novo in response to various biotic and abiotic stressors. The importance of stilbenes in plant resistance to stress and disease is of increasing interest. However, the defense mechanisms and potential of stilbenes to improve plant stress tolerance have not been thoroughly reviewed. This work overviewed the pentose phosphate pathway, glycolysis pathway, shikimate pathway, and phenylalanine pathway occurred in the synthesis of stilbenes when plants are subjected to biotic and abiotic stresses. The positive implications and underlying mechanisms regarding defensive properties of stilbenes were demonstrated. Ten biomimetic chemosynthesis methods can underpin the potential of stilbenes to improve plant stress tolerance. The prospects for the application of stilbenes in agriculture, food, cosmetics, and pharmaceuticals industries are anticipated. It is hoped that some of the detailed ideas and practices may contribute to the development of stilbene-related products and improvement of plant resistance breeding.

Ehrlichia chaffeensis Etf-3 Induces Host RAB15 Upregulation for Bacterial Intracellular Growth.

Ehrlichia chaffeensis infects human monocytes or macrophages and causes human monocytic ehrlichiosis (HME), an emerging life-threatening zoonosis. After internalization, E. chaffeensis resides in membrane-bound inclusions, E. chaffeensis-containing vesicles (ECVs), which have early endosome-like characteristics and fuse with early autophagosomes but not lysosomes, to evade host innate immune microbicidal mechanisms and obtain nutrients for bacterial intracellular growth. The mechanisms exploited by E. chaffeensis to modulate intracellular vesicle trafficking in host cells have not been comprehensively studied. Here, we demonstrate that E. chaffeensis type IV secretion system (T4SS) effector Etf-3 induces RAB15 upregulation in host cells and that RAB15, which is localized on ECVs, inhibits ECV fusion with lysosomes and induces autophagy. We found that E. chaffeensis infection upregulated RAB15 expression using qRT-PCR, and RAB15 was colocalized with E. chaffeensis using confocal microscopy. Silence of RAB15 using siRNA enhanced ECV maturation to late endosomes and fusion with lysosomes, as well as inhibited host cell autophagy. Overexpression of Etf-3 in host cells specifically induced RAB15 upregulation and autophagy. Our findings deepen the understanding of E. chaffeensis pathogenesis and adaptation in hosts as well as the function of RAB15 and facilitate the development of new therapeutics for HME.

Heat shock proteins as a key defense mechanism in poultry production under heat stress conditions.

Over the past years, the poultry industry has been assigned to greater production performance but has become highly sensitive to environmental changes. The average world temperature has recently risen and is predicted to continue rising. In open-sided houses, poultry species confront high outside temperatures, which cause heat stress (HS) problems. Cellular responses are vital in poultry, as they may lead to identifying confirmed HS biomarkers. Heat shock proteins (HSP) are highly preserved protein families that play a significant role in cell function and cytoprotection against various stressors, including HS. The optimal response in which the cell survives the HS elevates HSP levels that prevent cellular proteins from damage caused by HS. The HSP have chaperonic action to ensure that stress-denatured proteins are folded, unfolded, and refolded. The HSP70 and HSP90 are the primary HSP in poultry with a defensive function during HS. HSP70 was the optimal biological marker for assessing HS among the HSP studied. The current review attempts to ascertain the value of HSP as a heat stress defense mechanism in poultry.

Antioxidant production promotes defense mechanism and different gene expression level in Zea mays under abiotic stress.

The growth and productivity of maize are severely affected by soil salinity. The crucial determinants for the future performance of plants are productive for seed germination and seedling establishment; however, both stages are liable to soil salinity. For grain, maize is an economically significant crop sensitive to abiotic stresses. However, little is known about defense responses by the salinity-induced antioxidant and oxidative stress in maize. In our work, the commercially available maize variety Raka-Poshi was grown in pots for 30 days under greenhouse conditions. To evaluate the salt-induced oxidative/antioxidant responses in maize for salt stress 0, 25, 50, 75, 100 and 150 mM concentrations, treatments were provided using sodium chloride (NaCl). All the biochemical indices were calculated under all NaCl concentrations, while drought was induced by up to 50% irrigation water. After 30 days of seed germination, the maize leaves were collected for the measurement of lipid peroxidase or malondialdehyde (MDA), glutathione reductase (GR), guaiacol peroxidase (GPOD), hydrogen peroxide (H2O2), superoxide dismutase (SOD), lipoxygenase (LOX), catalase (CAT), ascorbate peroxidase (APOD) and glutathione-S-transferase (GST). The results revealed a 47% reduction under 150 mM NaCl and 50% drought stress conditions. The results have shown that the successive increase of NaCl concentrations and drought caused an increase in catalase production. With successive increase in NaCl concentration and drought stress, lower levels of H2O2, SOD, and MDA were detected in maize leaves. The results regarding the morphology of maize seedlings indicated a successive reduction in the root length and shoot length under applications of salt and drought stress, while root-to-shoot weights were found to be increased under drought stress and decreased under salt stress conditions During gene expression analysis collectively indicate that, under drought stress conditions, the expression levels of all nine mentioned enzyme-related genes were consistently downregulated.

Biochemical responses and antioxidant defense mechanisms in Channa Striatus exposed to Bisphenol S.

Bisphenol S (BPS), a BPA analog and a safer alternative, is utilized in a diverse range of industrial applications, such as making polycarbonate plastics, epoxy resins, thermal receipt papers, and currency bills. Recently, the increased use of BPS in containers and packages for daily life has been interrogated due to its identical chemical structure and probable endocrine-disrupting actions as BPA has. The present study aimed to evaluate the alterations in biochemical indices and antioxidant enzymes as certain indicators of the endocrine-disrupting effect of BPS in Channa striatus, a freshwater fish. BPS-exposed fish species were subjected to three sub-lethal concentrations of BPS (1, 4, and 12 ppm) and observed after an interval of 7 and 21 days. Exposure to BPS caused a reduction in the level of protein in muscle, gonads and the liver due to an impairment of protein synthesis. Levels of cholesterol in the muscle, gonads, and liver of BPS-exposed fish were found to be decreased after treatment, indicating either an inhibition of cholesterol biosynthesis in the liver or reduced absorption of dietary cholesterol. The levels of antioxidant enzymes such as superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase showed remarkable increases, while the activity of glutathione S-transferase decreased considerably, indicating the antioxidant defense mechanism to counteract the oxidative stress induced by BPS. Moreover, a significant increase was noted in the level of lipid peroxidation products, like malondialdehyde and conjugate diene, which represent biomarkers of oxidative stress. The histoarchitecture changes were also observed in the liver, muscle and gonads of BPS-treated fish species. The present study showed that sub-lethal exposure to BPS significantly influenced the activities of these enzymes and peroxidation byproducts. From this study, it is concluded that BPS-caused toxic effects in fish species lead to an imbalance in the antioxidant defense system. It is clearly indicated that BPS toxicity could lead to susceptible oxidative stress in various tissues and could damage vital organs.

Physiological and biochemical responses of Leersia hexandra Swartz to nickel stress: Insights into antioxidant defense mechanisms and metal detoxification strategies.

Phytoremediation is widely considered as a cost-effective method for managing heavy metal soil pollution. Leersia hexandra Swartz shows a promising potential for the remediation of heavy metals pollution, including chromium (Cr), copper (Cu), and nickel (Ni). It is vital to understand the physiological and biochemical responses of L. hexandra to Ni stress to elucidate the mechanisms underlying Ni tolerance and accumulation. Here, we examined the metabolic and transcriptomic responses of L. hexandra exposed to 40 mg/L Ni for 24 h and 14 d. After 24-h Ni stress, gene expression of glutathione metabolic cycle (GSTF1, GSTU1 and MDAR4) and superoxide dismutase (SODCC2) was significantly increased in plant leaves. Furthermore, after 14-d Ni stress, the ascorbate peroxidase (APX7), superoxide dismutase (SODCP and SOD1), and catalase (CAT) gene expression was significantly upregulated, but that of glutathione metabolic cycle (EMB2360, GSTU1, GSTU6, GSH2, GPX6, and MDAR2) was downregulated. After 24-h Ni stress, the differentially expressed metabolites (DEMs) were mainly flavonoids (45%) and flavones (20%). However, after 14-d Ni stress, the DEMs were mainly carbohydrates and their derivatives (34%), amino acids and derivatives (15%), and organic acids and derivatives (8%). Results suggest that L. hexandra adopt distinct time-dependent antioxidant and metal detoxification strategies likely associated with intracellular reduction-oxidation balance. Novel insights into the molecular mechanisms responsible for Ni tolerance in plants are presented.

Plant-Growth-Promoting Rhizobacteria Modulate Carbohydrate Metabolism in Connection with Host Plant Defense Mechanism.

Plant-growth-promoting rhizobacteria (PGPR) could potentially enhance photosynthesis and benefit plant growth by improving soil nutrient uptake and affecting plant hormone balance. Several recent studies have unveiled a correlation between alterations in photosynthesis and host plant resistance levels. Photosynthesis provides materials and energy for plant growth and immune defense and affects defense-related signaling pathways. Photosynthetic organelles, which could be strengthened by PGPR inoculation, are key centers for defense signal biosynthesis and transmission. Although endophytic PGPRs metabolize plant photosynthates, they can increase soluble sugar levels and alternate sugar type and distribution. Soluble sugars clearly support plant growth and can act as secondary messengers under stressed conditions. Overall, carbohydrate metabolism modifications induced by PGPR may also play a key role in improving plant resistance. We provide a concise overview of current knowledge regarding PGPR-induced modulation in carbohydrate metabolism under both pathogen-infected and pathogen-free conditions. We highlight PGPR application as a cost-saving strategy amidst unpredictable pathogen pressures.

Arabic gum/chitosan/Zn-NPs composite film maintains the quality of Hass avocado fruit by delaying ripening and activating enzymatic defense mechanisms.

Avocado fruit is a climacteric fruit that has a short life after harvest. Chitosan (Ch) and Arabic gum (AG) have a pronounced effect on the storability of fruits. This investigation aimed to determine the effect of individual or combined use of Ch and AG as well as Ch/AG enriched with 2, 4, 8% Zn-NPs on physio-biochemical attributes and antioxidant capacity of Hass avocado fruit during cold storage (7 °C). The result showed that Ch or AG alone succeeded in maintaining fruit quality of Hass fruit during cold storage. Also, combined application of Ch/AG was more effective than individual application of Ch or AG in reducing fruit weight and polyphenol oxidase activity (PPO) as well as increasing total antioxidant capacity (TAC) and malondialdehyde (MDA). Moreover, Ch/AG coating enriched with 8% Zn-NPs recorded the lowest fruit weight loss, fruit decay %, TSS fruit content, fruit firmness and improved fruit skin and pulp color significantly compared to Ch/AG and control. Coating with Ch/AG/2%Zn NPs recorded the highest peroxidase (POD) activity, while Ch/AG/8% Zn-NPs recorded the highest TAC and the lowest PPO activity. Moreover, enriched Ch/GA with Zn-NPs recorded the highest CAT and POD activity compared to the control. This study shows the efficiency of Ch/AG enriched with Zn-NPs on preserving Hass avocado fruit quality during cold storage by delaying ripening process and activating enzymatic defense mechanisms.

The effect of a task-specific training on upper limb performance and kinematics while performing a reaching task in a fatigued state.

BACKGROUND: Fatigue impacts motor performance and upper limb kinematics. It is of interest to study whether it is possible to minimize the potentially detrimental effects of fatigue with prevention programs. OBJECTIVE: To determine the effect of task-specific training on upper limb kinematics and motor performance when reaching in a fatigued state. METHODS: Thirty healthy participants were recruited (Training group n = 15; Control group n = 15). Both groups took part in two evaluation sessions (Day 1 and Day 5) during which they performed a reaching task (as quickly and accurately as possible) in two conditions (rested and fatigued). During the reaching task, joint kinematics and motor performance (accuracy and speed) were evaluated. The Training group participated in three task-specific training sessions between Day 1 and Day 5; they trained once a day, for three days. The Control group did not perform any training. A three-way non-parametric ANOVA for repeated measures (Nonparametric Analysis of Longitudinal Data; NparLD) was used to assess the impact of the training (Condition [within subject]: rested, fatigued; Day [within subject]: Day 1 vs. Day 5 and Group [between subjects]: Training vs. Control). RESULTS: After the training period, the Training group significantly improved their reaching speed compared to the Control group (Day x Group p < .01; Time effect: Training group = p < .01, Control group p = .20). No between-group difference was observed with respect to accuracy. The Training group showed a reduction in contralateral trunk rotation and lateral trunk flexion in Day 2 under the fatigue condition (Group x Day p < .04; Time effect: Training group = p < .01, Control group = p < .59). CONCLUSION: After the 3-day training, participants demonstrated improved speed and reduced reliance on trunk compensations to complete the task under fatigue conditions. Task-specific training could help minimizing some effects of fatigue.

Establishment of Mouse Orthotopic Urinary Bladder Tumor Model and Its Analysis by Light and Electron Microscopy.

Mouse tumor models are an important tool in cancer research, and the orthotopic cancer cell transplantation model is the most widely used among them. Methods for establishing tumor models may differ in many ways, including the selection of cancer cell lines and the type of urinary bladder pretreatment. Here, we describe our mouse orthotopic bladder tumor model using a labeled MB49 urothelial cancer cell line and chemical pretreatment with the cationic polypeptide poly-L-lysine to traumatize the bladder epithelium. Double labeling of MB49 cancer cells by their transduction with GFP and internalization of metal nanoparticles allows the study of their implantation process from the first hours to several days after intravesical injection, as well as the analysis of developed tumors after 3 weeks. Thus, our model provides a comprehensive analysis of the early and late stages of tumor development in the bladder at the light and electron microscopic level.

Acidosis defense mechanisms in the preimplantation stages of embryos in BALB/c strain mice.

Regulation of intracellular pH (pHi) is an important homeostatic function of cells. There are three major pHi regulatory mechanisms: the HCO3-/Cl- exchanger (AE), which alleviates alkalosis, and the Na+/H+ exchanger (NHE) and Na+,HCO3-/Cl- exchanger (NDBCE), both of which counteract acidosis. NHE activity, which is high at the germinal vesicle stage of oocyte, is inhibited during meiotic maturation, while this inhibition is abolished when the oocyte reaches the pronuclear (PN) stage of the zygote. On the other hand, we have previously found that NDBCE performs complementary regulation against acidosis during meiotic maturation. Additionally, we found that AE activity, which is a defense mechanism against alkalosis, gradually decreases during preimplantation period of embryonic development. Considering that NHE activity is inhibited during meiotic maturation and AE activity gradually decreases during embryonic development stages, we investigated whether NHE and NDBCE activities, both of which act against acidosis, functionally change from the PN zygote to the blastocyst stage of the embryo and identified these pH-regulating proteins at the molecular level in mice of the Balb/c strain. PN zygotes, two-cell (2-c), four-cell (4-c), morula and blastocyst stage embryos were obtained from 5-8-week-old, sexually mature female Balb/c mice by using the classical superovulation procedure. pHi was recorded by using the microspectrofluorometric technique on zygotes and embryos simultaneously loaded with the pH-sensitive fluorophore, 2',7'-Bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF). The activities of NHE and NDBCE were determined from the recovery curve of induced-acidosis in bicarbonate-free and bicarbonate-containing media, respectively. Specific inhibitors such as cariporide (1 µM), S3226 (1 and 10 µM), EIPA (1, 5, and 25 µM), and amiloride (1 mM) were used to functionally identify NHE isoforms, and the nonspecific inhibitor 4,4'-diisocyanatostilbene-2,2' disulphonic acid, disodium salt (DIDS) was used to confirm NDBCE activity. The isoforms of the pHi-regulatory proteins were also identified by molecular biology using real-time PCR. We found that NHE activity was high at all embryonic stages, and differences between stages were not significant. Functional and molecular findings indicated that isoforms of NHE 1 and 5 are present in the blastocyst, whereas isoforms of NHE 1, 3, and 4 are functional at earlier embryonic stages. Although the contribution of NDBCE activity to recovery from induced-acidosis was detected at all embryonic stages, it was significant only in the PN zygote and the 2-c embryo. This finding was confirmed by molecular analysis, which detected the expression of SLC4A8 encoding NDBCE at all embryonic stages. In conclusion, NHE is an active and important defense mechanism against acidosis and is encoded by at least two protein isoforms in all stages of the Balb/c strain of mice. NDBCE has a supportive function in all embryonic stages, especially in the PN zygote and the 2-c embryo. Preimplantation stage embryos have effective mechanisms to defend against acidosis in response to their metabolic end products (increased acid load) and the acidic environment in utero.

Leaf abaxial immunity to powdery mildew in Arabidopsis is conferred by multiple defense mechanisms.

Powdery mildew fungi are obligate biotrophic pathogens that only invade plant epidermal cells. There are two epidermal surfaces in every plant leaf: the adaxial (upper) side and the abaxial (lower) side. While both leaf surfaces can be susceptible to adapted powdery mildew fungi in many plant species, there have been observations of leaf abaxial immunity in some plant species including Arabidopsis. The genetic basis of such leaf abaxial immunity remains unknown. In this study, we tested a series of Arabidopsis mutants defective in one or more known defense pathways with the adapted powdery mildew isolate Golovinomyces cichoracearum UCSC1. We found that leaf abaxial immunity was significantly compromised in mutants impaired for both the EDS1/PAD4- and PEN2/PEN3-dependent defenses. Consistently, expression of EDS1-yellow fluorescent protein and PEN2-green fluorescent protein fusions from their respective native promoters in the respective eds1-2 and pen2-1 mutant backgrounds was higher in the abaxial epidermal cells than in the adaxial epidermal cells. Altogether, our results indicate that leaf abaxial immunity against powdery mildew in Arabidopsis is at least partially due to enhanced EDS1/PAD4- and PEN2/PEN3-dependent defenses. Such transcriptionally pre-programmed defense mechanisms may underlie leaf abaxial immunity in other plant species such as hemp and may be exploited for engineering adaxial immunity against powdery mildew fungi in crop plants.

Silencing Very-Low-Density Lipoprotein Receptor Reveals Alpha-1 Antitrypsin Role in HIV Infectivity.

Here we describe methods for investigating alpha-1 antitrypsin (AAT) and very-low-density lipoprotein receptor (VLDLR) interactions with infectious and non-infectious HIV-1 virions. Using silencing RNA to transiently block expression of VLDLR and the receptor-associated protein (RAP) to continuously block VLDLR activity, AAT is demonstrated to participate with VLDLR during internalization and infectivity of HIV-1 virions.

Norsesquiterpenes from the Latex of Euphorbia dentata and Their Chemical Defense Mechanisms against Helicoverpa armigera.

Euphorbia dentata (Euphorbiaceae), an invasive weed, is rarely eaten by herbivorous insects and could secrete a large amount of white latex, causing a serious threat to local natural vegetation, agricultural production and human health. In order to prevent this plant from causing more negative effects on humans, it is necessary to understand and utilize the chemical relationships between the latex of E. dentata and herbivorous insects. In this study, three new norsesquiterpenes (1-3), together with seven known analogues (4-10), were isolated and identified from the latex of E. dentata. All norsesquiterpenes (1-10) showed antifeedant and growth-inhibitory effects on H. armigera with varying levels, especially compounds 1 and 2. In addition, the action mechanisms of active compounds (1-3) were revealed by detoxifying enzyme (AchE, CarE, GST and MFO) activities and corresponding molecular docking analyses. Our findings provide a new idea for the development and utilization of the latex of E. dentata, as well as a potential application of norsesquiterpenes in botanical insecticides.

Oxidative Stress and Antioxidant Defense Mechanisms in Acute Ischemic Stroke Patients with Concurrent COVID-19 Infection.

Stroke remains a debilitating cerebrovascular condition associated with oxidative stress, while COVID-19 has emerged as a global health crisis with multifaceted systemic implications. This study investigates the hypothesis that patients experiencing acute ischemic stroke alongside COVID-19 exhibit elevated oxidative stress markers and altered antioxidant defense mechanisms compared to those with acute ischemic stroke. We conducted a single-center prospective cross-sectional study to investigate oxidative stress balance through oxidative damage markers: TBARS (thiobarbituric acid reactive substances level) and PCARB (protein carbonyls); antioxidant defense mechanisms: TAC (total antioxidant capacity), GPx (glutathione peroxidase), GSH (reduced glutathione), CAT (catalase), and SOD (superoxide dismutase); as well as inflammatory response markers: NLR (neutrophil-to-lymphocyte ratio), CRP (C-reactive protein), and ESR (erythrocyte sedimentation rate). Statistical analyses and correlation models were employed to elucidate potential associations and predictive factors. Our results revealed increased oxidative stress, predominantly indicated by elevated levels of TBARS in individuals experiencing ischemic stroke alongside a concurrent COVID-19 infection (p < 0.0001). The Stroke-COVID group displayed notably elevated levels of GSH (p = 0.0139 *), GPx (p < 0.0001 ****), SOD (p = 0.0363 *), and CAT (p = 0.0237 *) activities. Multivariate analysis found a significant association for TBARS (p < 0.0001 ****), PCARB (p = 0.0259 *), and GPx activity (p < 0.0001 ****), together with NLR (p = 0.0220 *) and CRP (p = 0.0008 ***). Notably, the interplay between stroke and COVID-19 infection appears to amplify oxidative damage, potentially contributing to exacerbated neurological deficits and poorer outcomes. This study highlights the intricate relationship between oxidative stress, inflammation, and concurrent health conditions. Understanding these interactions may open avenues for novel therapeutic strategies aimed at ameliorating oxidative damage in patients with acute ischemic stroke and COVID-19, ultimately improving their prognosis and quality of life.

Recognition: A Key for Understanding a Necessary Role of the Psychotherapist for the Successful Outcome of Psychotherapy.

The purpose of this paper is to focus on an aspect of psychodynamic psychotherapy that includes psychoanalysis to illustrate the important element in the psychotherapeutic relationship called recognition. This involves an emotional sharing with the patient of the importance of particular life experiences that he has had and as such this not only cements the relationship but becomes the substrate of change and an internalization of the therapist that persists after the end of treatment. This interaction parallels the experience with a responsive mother able to echo the infant's experience. The experience of recognition is illustrated with 10 case presentations that demonstrate the power of this factor in a variety of patients ranging from brief consultations to psychoanalysis.

Aportes del psicoanálisis a los estudios de abuso sexual infantil: Análisis del discurso de la madre de una niña abusada sexualmente / Contributions of psychoanalysis to studies of child sexual abuse: Mother's speech analysis about her sexually abused daughter

Se presentan los resultados dela tesis doctoral sobre los deseos y defensas (y sus estados) de la madre de una niña abusada sexualmente, con el objetivo de conocer su estructuración subjetiva en este difícil acontecimiento. Se trata de un estudio de caso en el que se usa como método el Algoritmo David Liberman (ADL), en el análisis del discurso de la madre, seleccionadas tres sesiones y una carta manuscrita. El estudio de deseos y defensas puede contribuir a describir y conocer el posicionamiento subjetivo de una madre frente a la situación abusiva de su hija, y como ésta es vivida por ella AU

The results of the doctoral thesis on the wishes and defenses (and their states) of the mother of a sexually abused girl are presented, with the aim of knowing her subjective structuring in this difficult event. This is a case study in which the David Liberman Algorithm (ADL) is used as a method in the analysis of the mother's speech, three sessions and a handwritten letter selected. The study of desires and defenses can contribute to describing and knowing the subjective position of a mother in the face of her daughter's abusive situation, and how it is experienced by her AU

Comparative Analysis of Transcriptomics and Metabolomics Reveals Defense Mechanisms in Melon Cultivars against Pseudoperonospora cubensis Infection.

Melon (Cucumis melo L.) represents an agriculturally significant horticultural crop that is widely grown for its flavorful fruits. Downy mildew (DM), a pervasive foliar disease, poses a significant threat to global melon production. Although several quantitative trait loci related to DM resistance have been identified, the comprehensive genetic underpinnings of this resistance remain largely uncharted. In this study, we utilized integrative transcriptomics and metabolomics approaches to identify potential resistance-associated genes and delineate the strategies involved in the defense against DM in two melon cultivars: the resistant 'PI442177' ('K10-1') and the susceptible 'Huangdanzi' ('K10-9'), post-P. cubensis infection. Even in the absence of the pathogen, there were distinctive differentially expressed genes (DEGs) between 'K10-1' and 'K10-9'. When P. cubensis was infected, certain genes, including flavin-containing monooxygenase (FMO), receptor-like protein kinase FERONIA (FER), and the HD-ZIP transcription factor member, AtHB7, displayed pronounced expression differences between the cultivars. Notably, our data suggest that following P. cubensis infection, both cultivars suppressed flavonoid biosynthesis via the down-regulation of associated genes whilst concurrently promoting lignin production. The complex interplay of transcriptomic and metabolic responses elucidated by this study provides foundational insights into melon's defense mechanisms against DM. The robust resilience of 'K10-1' to DM is attributed to the synergistic interaction of its inherent transcriptomic and metabolic reactions.

Polystyrene nanoparticles induce concerted response of plant defense mechanisms in plant cells.

Recent advances in knowledge suggest that micro- and nanoplastics pose a threat to plant health, however, the responses of plants to this stressor are not well-known. Here we examined the response of plant cell defence mechanisms to nanoparticles of commonly used plastic, polystyrene. We used plant cell cultures of widely cultivated plants, the monocots wheat and barley (Triticum aestivum L., Hordeum vulgare L.) and the dicots carrot and tomato (Daucus carota L., Solanum lycopersicum L.). We measured the activities of enzymes involved in the scavenging of reactive oxygen species and nonenzymatic antioxidants and we estimated potential damages in plant cell structures and functioning via lipid peroxidation and DNA methylation levels. Our results demonstrate that the mode of action of polystyrene nanoparticles on plant cells involves oxidative stress. However, the changes in plant defence mechanisms are dependent on plant species, exposure time and nanoplastic concentrations. In general, both monocots showed similar responses to nanoplastics, but the carrot followed more the response of monocots than a second dicot, a tomato. Higher H2O2, lipid peroxidation and lower enzyme activities scavenging H2O2 suggest that tomato cells may be more susceptible to polystyrene-induced stress. In conclusion, polystyrene nanoplastics induce oxidative stress and the response of the plant defense mechanisms involving several chain reactions leading to oxidoreductive homeostasis.

Polytraumatization, defense mechanisms, PTSD and complex PTSD in Indian adolescents: a mediation model.

BACKGROUND: Adolescence is recognized as a particularly susceptible developmental period for experiencing multiple types of Adverse Childhood Experiences (ACE), increasing the vulnerability to higher levels of Post-Traumatic Stress Disorder (PTSD) and Complex PTSD symptoms. Some studies found that defense mechanisms play an important role on the association between ACE and psychological symptoms. METHODS: We analyzed the associations between direct and indirect exposure to ACE and PTSD and Complex PTSD (affective dysregulation, negative self-concept and disturbances in relationships) through the mediation role of mature defense mechanisms: mature, neurotic, and immature defense mechanisms in Indian adolescents. A sample of 411 Indian adolescents (M = 14.2 years old; S.D. = 0.5) completed validated self-report questionnaires. Serial multiple mediation models were tested by conducting a structural equation modelling employing Preacher and Hayes' procedures (2008). RESULTS: Immature and neurotic defense mechanisms mediated the association between direct exposure to ACE with PTSD symptoms. Immature defense mechanisms were mediators of the relationship between direct exposure to ACE and Complex PTSD symptoms clusters. CONCLUSIONS: Maladaptive defense mechanisms can disturb the process of self-regulation and emotion regulation capabilities in coping with traumatic experiences, leading to higher PTSD and Complex PTSD symptoms severity.