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Scientific Reports Aug 2023Animal and human feces typically include intestinal sulfate-reducing bacteria (SRB). Hydrogen sulfide and acetate are the end products of their dissimilatory sulfate...
Animal and human feces typically include intestinal sulfate-reducing bacteria (SRB). Hydrogen sulfide and acetate are the end products of their dissimilatory sulfate reduction and may create a synergistic effect. Here, we report NADH and NADPH peroxidase activities from intestinal SRB Desulfomicrobium orale and Desulfovibrio piger. We sought to compare enzymatic activities under the influence of various temperature and pH regimes, as well as to carry out kinetic analyses of enzymatic reaction rates, maximum amounts of the reaction product, reaction times, maximum rates of the enzyme reactions, and Michaelis constants in cell-free extracts of intestinal SRB, D. piger Vib-7, and D. orale Rod-9, collected from exponential and stationary growth phases. The optimal temperature (35 °C) and pH (7.0) for both enzyme's activity were determined. The difference in trends of Michaelis constants (K) during exponential and stationary phases are noticeable between D. piger Vib-7 and D. orale Rod-9; D. orale Rod-9 showed much higher K (the exception is NADH peroxidase of D. piger Vib-7: 1.42 ± 0.11 mM) during the both monitored phases. Studies of the NADH and NADPH peroxidases-as putative antioxidant defense systems of intestinal SRB and detailed data on the kinetic properties of this enzyme, as expressed by the decomposition of hydrogen peroxide-could be important for clarifying evolutionary mechanisms of antioxidant defense systems, their etiological role in the process of dissimilatory sulfate reduction, and their possible role in the development of bowel diseases.
Topics: Animals; Humans; Antioxidants; NAD; NADP; Cell Extracts; Desulfovibrio; Peroxidases; Defense Mechanisms; Sulfates
PubMed: 37626119
DOI: 10.1038/s41598-023-41185-3 -
BMC Plant Biology Jul 2022Rice (Oryza sativa L.) is the major source of daily caloric intake for more than 30% of the human population. However, the sustained productivity of this staple food... (Review)
Review
BACKGROUND
Rice (Oryza sativa L.) is the major source of daily caloric intake for more than 30% of the human population. However, the sustained productivity of this staple food crop is continuously threatened by various pathogens and herbivores. Breeding has been successful in utilizing various mechanisms of defense by gene pyramiding in elite cultivars, but the continuous resurgence of highly resistant races of pathogens and herbivores often overcomes the inherent capacity of host plant immunity. MicroRNAs (miRNAs) are endogenous, short, single-stranded, non-coding RNA molecules that regulate gene expression by sequence-specific cleavage of target mRNA or suppressing target mRNA translation. While miRNAs function as upstream regulators of plant growth, development, and host immunity, their direct effects on growth and development in the context of balancing defenses with agronomic potential have not been extensively discussed and explored as a more viable strategy in breeding for disease and pest resistant cultivars of rice with optimal agronomic potentials.
RESULTS
Using the available knowledge in rice and other model plants, this review examines the important roles of miRNAs in regulating host responses to various fungal, bacterial, and viral pathogens, and insect pests, in the context of gains and trade-offs to crop yield. Gains from R-gene-mediated resistance deployed in modern rice cultivars are often undermined by the rapid breakdown of resistance, negative pleiotropic effects, and linkage drags with undesirable traits. In stark contrast, several classes of miRNAs are known to efficiently balance the positive gains from host immunity without significant costs in terms of losses in agronomic potentials (i.e., yield penalty) in rice. Defense-related miRNAs such as Osa-miR156, Osa-miR159, Osa-miR162, Osa-miR396, Osa-530, Osa-miR1432, Osa-miR1871, and Osa-miR1873 are critical in fine-tuning and integrating immune responses with physiological processes that are necessary to the maintenance of grain yield. Recent research has shown that many defense-related miRNAs regulate complex and agronomically important traits.
CONCLUSIONS
Identification of novel immune-responsive miRNAs that orchestrate physiological processes critical to the full expression of agronomic potential will facilitate the stacking of optimal combinations of miRNA-encoding genes to develop high-yielding cultivars with durable resistance to disease and insect pests with minimal penalties to yield.
Topics: Defense Mechanisms; Gene Expression Regulation, Plant; Herbivory; Humans; MicroRNAs; Oryza; Plant Breeding; Plants, Genetically Modified
PubMed: 35850632
DOI: 10.1186/s12870-022-03723-5 -
Medical Science Monitor : International... Jun 2015It is a struggle to identify the most adaptive coping strategies with disease-mediated stress. Here, we hypothesize that intensity of coping strategies, including...
BACKGROUND
It is a struggle to identify the most adaptive coping strategies with disease-mediated stress. Here, we hypothesize that intensity of coping strategies, including denial, in patients with end-stage renal disease (ESRD), varies with type of renal replacement therapy (RRT).
MATERIAL AND METHODS
We enrolled 60 in-center hemodialyzed patients (HD) and 55 patients treated with continuous ambulatory peritoneal dialysis (CAPD). We administered the Coping Inventory with Stressful Situation, Profile of Mood States, and Stroop Anxiety Inventory to measure patient coping strategies in the context of their ESRD. Denial defense mechanism was measured via the IBS-R/ED. The Nottingham Health Profile was used to evaluate self-perceived quality of life. Serum potassium, urea, creatinine, phosphorus, calcium, albumin, and hematocrit were utilized as the measurements of adequacy of dialysis.
RESULTS
HD patients had higher self-reported intensity of denial mechanism and avoidance-oriented strategies versus CAPD patients. Because a single strategy is almost never employed, we conducted cluster analysis. We identify 3 patterns of coping strategies using cluster analysis. "Repressors" employed denial and avoidance strategies and were predominant in HD. The second cluster consists of subjects employing predominantly task-oriented strategies with equal distribution among dialyzed patients. The third cluster encompassed a small group of patients who shared higher intensity of both denial and task-oriented strategies. Health-related outcome, anxiety, and mood profile were similar across all patients.
CONCLUSIONS
HD patients predominantly used "repressive" strategies. Patients on RRT utilized denial and avoidance-based strategies to achieve satisfactory outcome in terms of perceived quality of life. We conclude that these coping mechanisms that were previously thought to be inferior are beneficial to patient compliance with RRT.
Topics: Adaptation, Psychological; Adult; Affect; Aged; Albumins; Anxiety; Calcium; Cohort Studies; Creatinine; Cross-Sectional Studies; Denial, Psychological; Female; Hematocrit; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peritoneal Dialysis, Continuous Ambulatory; Phosphorus; Potassium; Quality of Life; Renal Dialysis; Statistics, Nonparametric; Urea
PubMed: 26094792
DOI: 10.12659/MSM.893331 -
Microbiology Spectrum Apr 2016Invading pathogens are exposed to a multitude of harmful conditions imposed by the host gastrointestinal tract and immune system. Bacterial defenses against these... (Review)
Review
Invading pathogens are exposed to a multitude of harmful conditions imposed by the host gastrointestinal tract and immune system. Bacterial defenses against these physical and chemical stresses are pivotal for successful host colonization and pathogenesis. Enteric pathogens, which are encountered due to the ingestion of or contact with contaminated foods or materials, are highly successful at surviving harsh conditions to colonize and cause the onset of host illness and disease. Pathogens such as Campylobacter, Helicobacter, Salmonella, Listeria, and virulent strains of Escherichia have evolved elaborate defense mechanisms to adapt to the diverse range of stresses present along the gastrointestinal tract. Furthermore, these pathogens contain a multitude of defenses to help survive and escape from immune cells such as neutrophils and macrophages. This chapter focuses on characterized bacterial defenses against pH, osmotic, oxidative, and nitrosative stresses with emphasis on both the direct and indirect mechanisms that contribute to the survival of each respective stress response.
Topics: Adaptation, Physiological; Animals; Bacteria; Bacterial Physiological Phenomena; Defense Mechanisms; Gastrointestinal Tract; Humans; Microbial Viability; Stress, Physiological; Virulence
PubMed: 27227312
DOI: 10.1128/microbiolspec.VMBF-0007-2015 -
Translational Psychiatry Jan 2023Despite the clinical relevance of defense mechanisms, there are no published studies in nationally representative samples of their prevalence, correlates, and...
Despite the clinical relevance of defense mechanisms, there are no published studies in nationally representative samples of their prevalence, correlates, and association with psychosocial functioning. We sought to estimate the prevalence and correlates of 12 defense mechanisms in the general adult population by approximating from items used to assess personality traits in the National Epidemiological Survey on Alcohol and Related Conditions (NESARC), a representative sample of US adults (N = 36,653). We examined the associations between sociodemographic characteristics and prevalence of 3 types of defenses mechanisms (pathological, immature, and neurotic). For each defense mechanism, we used the Short-Form 12 to compare psychosocial functioning among 3 groups: those who (1) endorsed the mechanism with self-recognized impairment, (2) endorsed the mechanism without self-recognized impairment, and (3) did not endorse the defense mechanism. The prevalence of defense mechanisms ranged from 13.2% (splitting) to 44.5% (obsessive/controlling behavior). Pathological defenses were more strongly associated with immature defenses (OR = 5.4, 95% CI = 5.2-5.6) than with neurotic defenses (OR = 2.0, 95% CI = 1.9-2.0), whereas the association between immature and neurotic defenses had an intermediate value between the other two (OR = 2.2, 95% CI = 2.1-2.2). Pathological and immature defenses were associated with younger age, having been never married, lower educational attainment, and lower income. After adjusting the crude results for age and sex, individuals who did not endorse a given defense generally had higher scores on the mental health component of the SF-12 than those who endorsed the defense without self-recognized impairment who, in turn, had on average higher scores than those with self-recognized impairment. These results suggest that neurotic, immature, and pathological defense mechanisms are prevalent in the general population and associated with psychosocial impairment. Recognizing defense mechanisms may be important in clinical practice regardless of treatment modality.
Topics: Humans; Adult; Defense Mechanisms; Prevalence; Surveys and Questionnaires
PubMed: 36690611
DOI: 10.1038/s41398-022-02303-3 -
International Journal of Molecular... Jan 2024Plant-growth-promoting rhizobacteria (PGPR) could potentially enhance photosynthesis and benefit plant growth by improving soil nutrient uptake and affecting plant... (Review)
Review
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.
Topics: Plant Development; Plant Growth Regulators; Carbohydrate Metabolism; Alphaproteobacteria; Sugars; Defense Mechanisms
PubMed: 38338742
DOI: 10.3390/ijms25031465 -
Psychology of Addictive Behaviors :... Sep 2011Research emanating from the field of developmental science indicates that initial risk factors for alcohol use and disorder can be evident in early childhood. One... (Review)
Review
Research emanating from the field of developmental science indicates that initial risk factors for alcohol use and disorder can be evident in early childhood. One dominant developmental pathway connecting these initial risk factors with subsequent alcohol involvement focuses on the central role of disinhibited or externalizing behaviors. In the current paper, we delineate a second pathway that focuses on internalizing symptomatology. Several studies indicate that internalizing symptoms in early and middle childhood predict alcohol involvement in adolescence and young adulthood. We use a developmental psychopathology framework to describe a risk model that traces the potential developmental markers of this internalizing pathway and to consider the relation between the internalizing pathway and the more widely researched externalizing pathway. We outline the markers of risk in this pathway and conclude with a discussion of the implications of this model for prevention efforts and future research. In this manner, we strive for a translational goal, linking our existing understanding of internalizing processes and alcohol use and disorder with our efforts to develop effective prevention programs.
Topics: Alcohol Drinking; Alcoholism; Anxiety; Defense Mechanisms; Depression; Humans; Personality Development; Risk Factors
PubMed: 21823762
DOI: 10.1037/a0024519 -
Frontiers in Psychology 2021The psychodynamic concept of defense mechanisms is nowadays considered by professionals with various theoretical orientations of great importance in the understanding of...
The psychodynamic concept of defense mechanisms is nowadays considered by professionals with various theoretical orientations of great importance in the understanding of human development and psychological functioning. More than half century of empirical research has demonstrated the impact of defensive functioning in psychological well-being, personality organization and treatment process-outcome. Despite the availability of a large number of measures for their evaluation, only a few instruments assess the whole hierarchy of defenses, based on the Defense Mechanisms Rating Scales (DMRS), which arguably offers an observer-rated gold standard of assessment. The present article illustrates the theoretical and methodological background of the DMRS-Q, the Q-sort version of the DMRS for clinical use. Starting from the definition and function of the 30 defense mechanisms included in the hierarchy, we extracted 150 items that captured a full range of defensive manifestations according to the DMRS theory. The DMRS-Q set is described in this paper with reference to the DMRS manual. Directions are also provided for using the DMRS-Q online software for the free and unlimited coding of defense mechanisms. After each coding, the DMRS-Q software provides a report including qualitative and quantitative scores reflecting the individual's defensive functioning. Qualitative scores are displayed as the (DPN), while quantitative scores are reported as Overall Defensive Functioning (ODF), defensive categories, defense levels, and individual defense mechanisms. Syntax for the scoring is displayed in the results and a clinical vignette of a psychotherapy session coded with the DMRS-Q is provided. The DMRS-Q is an easy-to-use, free, computerized measure that can help clinicians in monitoring changes in defense mechanisms, addressing therapeutic intervention, fostering symptoms decreasing and therapeutic alliance. Moreover, the DMRS-Q might be a valid tool for teaching the hierarchy of defense mechanisms and increase the observer-rated assessment of this construct in several research fields.
PubMed: 34721167
DOI: 10.3389/fpsyg.2021.718440 -
Journal of Pesticide Science Nov 2021Plants synthesize and accumulate a wide variety of compounds called secondary metabolites. Secondary metabolites serve as chemical barriers to protect plants from...
Plants synthesize and accumulate a wide variety of compounds called secondary metabolites. Secondary metabolites serve as chemical barriers to protect plants from pathogens and herbivores. Antimicrobial secondary metabolites are accumulated to prevent pathogen infection. These metabolites are classified into phytoalexins (induced in response to pathogen attack) and phytoanticipins (present prior to pathogen infection). The antimicrobial compounds in the grass family (Poaceae) were studied from the viewpoint of evolution. The studies were performed at three hierarchies, families, genera, and species and include the following: 1) the distribution of benzoxazinoids (Bxs) in the grass family, 2) evolutionary replacement of phytoanticipins from Bxs to hydroxycinnamic acid amide dimers in the genus , and 3) chemodiversity of flavonoid and diterpenoid phytoalexins in rice. These studies demonstrated dynamic changes in secondary metabolism during evolution, indicating the adaptation of plants to their environment by repeating scrap-and-build cycles.
PubMed: 34908899
DOI: 10.1584/jpestics.J21-05 -
Frontiers in Psychology 2021This is the first study to examine psychotherapists' levels of defense mechanisms, their concurrent relationship with professional work-related stress (professional...
This is the first study to examine psychotherapists' levels of defense mechanisms, their concurrent relationship with professional work-related stress (professional self-doubt and vicarious trauma), and how their levels of defense mechanisms predict the changes in these professional stresses over the course of 3 months since the start of the COVID-19 pandemic. Data from two online studies (Study 1; = 105 and Study 2; = 336), using two self-report measures of therapists' defense mechanisms (Defense Style Questionnaire-40 in Study 1 and Defense Mechanism Rating Scales Self-Report-30 in Study 2), are presented. Therapists reported higher levels of mature defense mechanisms, and lower levels of immature defense mechanisms, compared to published community and clinical populations assessed before and during the pandemic. Therapists' lower level of mature defense mechanisms and higher levels of neurotic and immature defense mechanisms were related to higher concurrent levels of vicarious trauma and professional doubt. Therapists who reported higher levels of mature defense mechanisms at 3-month follow-up showed less vicarious trauma and professional self-doubt at follow-up, after controlling for these professional stressors at baseline. Implications for clinical supervision and training are discussed. The context and professional challenges during the pandemic are unique and future replications of the results outside the pandemic context are warranted.
PubMed: 34393887
DOI: 10.3389/fpsyg.2021.647503