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Regulated cell death is a fundamental biological process that plays a crucial role in maintaining tissue homeostasis and eliminating damaged or unnecessary cells. Ferroptosis is an iron-dependent process, characterized by the accumulation of oxidized and damaged lipids, which leads to programmed cell death. Among the ferroptotic pathway genes regulating this process, GPX4, TFRC, ACSL4, FSP1, SLC7A11, and PROM2 could be considered. There are many well-known ferroptotic pathway regulators, which are discussed in this compact review. Cells with tissues of different origin display sensitive or resistant phenotypes to such regulators. In some cases, unexpected changes during cell treatment occurred, suggesting the possibility of regulating the death pathway. We assumed that possible changing of ferro-sensitivity to ferro-resistance in cells, especially in colorectal cancer cell lines, is responded for induced chemoresistance. Using novel techniques, such as CRISPR/Cas-9 genome editing, an induced phenotype "switching" is possible.

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In this paper, the characteristics of 40 so far described virophages-parasites of giant viruses-are given, and the similarities and differences between virophages and satellite viruses, which also, like virophages, require helper viruses for replication, are described. The replication of virophages taking place at a specific site-the viral particle factory of giant viruses-and its consequences are presented, and the defence mechanisms of virophages for giant virus hosts, as a protective action for giant virus hosts-protozoa and algae-are approximated. The defence systems of giant viruses against virophages were also presented, which are similar to the CRISPR/Cas defence system found in bacteria and in Archea. These facts, and related to the very specific biological features of virophages (specific site of replication, specific mechanisms of their defensive effects for giant virus hosts, defence systems in giant viruses against virophages), indicate that virophages, and their host giant viruses, are biological objects, forming a 'novelty' in biology.

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The human skin microbiome comprises diverse populations that differ temporally between body sites and individuals. The virome is a less studied component of the skin microbiome and the study of bacteriophages is required to increase knowledge of the modulation and stability of bacterial communities. Staphylococcus species are among the most abundant colonisers of skin and are associated with both health and disease yet the bacteriophages infecting the most abundant species on skin are less well studied. Here, we report the isolation and genome sequencing of 40 bacteriophages from human skin swabs that infect coagulase-negative Staphylococcus (CoNS) species, which extends our knowledge of phage diversity. Six genetic clusters of phages were identified with two clusters representing novel phages, one of which we characterise and name Alsa phage. We identified that Alsa phages have a greater ability to infect the species S. hominis that was otherwise infected less than other CoNS species by the isolated phages, indicating an undescribed barrier to phage infection that could be in part due to numerous restriction-modification systems. The extended diversity of Staphylococcus phages here enables further research to define their contribution to skin microbiome research and the mechanisms that limit phage infection.

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Predation is a dominant structuring force in ecological communities. In aquatic environments, predation on bivalves has long been an important focal interaction for ecological study because bivalves have central roles as ecosystem engineers, basal components of food webs, and commercial commodities. Studies of bivalves are common, not only because of bivalves' central roles, but also due to the relative ease of studying predatory effects on this taxonomic group. To understand patterns in the interactions of bivalves and their predators we synthesised data from 52 years of peer-reviewed studies on bivalve predation. Using a systematic search, we compiled 1334 studies from 75 countries, comprising 61 bivalve families (N = 2259), dominated by Mytilidae (29% of bivalves), Veneridae (14%), Ostreidae (8%), Unionidae (7%), and Dreissenidae and Tellinidae (6% each). A total of 2036 predators were studied, with crustaceans the most studied predator group (34% of predators), followed by fishes (24%), molluscs (17%), echinoderms (10%) and birds (6%). The majority of studies (86%) were conducted in marine systems, in part driven by the high commercial value of marine bivalves. Studies in freshwater ecosystems were dominated by non-native bivalves and non-native predator species, which probably reflects the important role of biological invasions affecting freshwater biodiversity. In fact, while 81% of the studied marine bivalve species were native, only 50% of the freshwater species were native to the system. In terms of approach, most studies used predation trials, visual analysis of digested contents and exclusion experiments to assess the effects of predation. These studies reflect that many factors influence bivalve predation depending on the species studied, including (i) species traits (e.g. behaviour, morphology, defence mechanisms), (ii) other biotic interactions (e.g. presence of competitors, parasites or diseases), and (iii) environmental context (e.g. temperature, current velocity, beach exposure, habitat complexity). There is a lack of research on the effects of bivalve predation at the population and community and ecosystem levels (only 7% and 0.5% of studies respectively examined impacts at these levels). At the population level, the available studies demonstrate that predation can decrease bivalve density through consumption or the reduction of recruitment. At the community and ecosystem level, predation can trigger effects that cascade through trophic levels or effects that alter the ecological functions bivalves perform. Given the conservation and commercial importance of many bivalve species, studies of predation should be pursued in the context of global change, particularly climate change, acidification and biological invasions.

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Bronchial asthma is a heterogeneous respiratory condition characterized by chronic airway inflammation, airway hyperresponsiveness and airway structural changes (known as remodeling). The clinical symptoms can be evoked by (non)specific triggers, and their intensity varies over time. In the past, treatment was mainly focusing on symptoms' alleviation; in contrast modern treatment strategies target the underlying inflammation, even during asymptomatic periods. Components of airway remodeling include epithelial cell shedding and dysfunction, goblet cell hyperplasia, subepithelial matrix protein deposition, fibrosis, neoangiogenesis, airway smooth muscle cell hypertrophy and hyperplasia. Among the other important, and frequently forgotten aspects of airway remodeling, also loss of epithelial barrier integrity, immune defects in anti-infectious defence and mucociliary clearance (MCC) dysfunction should be pointed out. Mucociliary clearance represents one of the most important defence airway mechanisms. Several studies in asthmatics demonstrated various dysfunctions in MCC - e.g., ciliated cells displaying intracellular disorientation, abnormal cilia and cytoplasmic blebs. Moreover, excessive mucus production and persistent cough are one of the well-recognized features of severe asthma and are also associated with defects in MCC. Damaged airway epithelium and impaired function of the ciliary cells leads to MCC dysfunction resulting in higher susceptibility to infection and inflammation. Therefore, new strategies aimed on restoring the remodeling changes and MCC dysfunction could present a new therapeutic approach for the management of asthma and other chronic respiratory diseases.

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This study investigated the potential for elevated temperature to alter the toxicity of acetamiprid (ACE) and thiacloprid (Thia) in the ecotoxicity model Daphnia magna. The modulation of CYP450 monooxygenases (ECOD), ABC transporter activity (MXR) and incident cellular reactive oxygen species (ROS) overproduction was screened in premature daphnids following acute (48 h) exposure to sublethal concentrations of ACE and Thia (0.1-, 1.0 µM) at standard 21 °C and elevated 26 °C temperatures. Delayed outcomes of acute exposures were further evaluated based on the reproduction performance of daphnids monitored over 14 days of recovery. Exposures to ACE and Thia at 21o C elicited moderate induction of ECOD activity, pronounced inhibition of MXR activity and severe ROS overproduction in daphnids. In the high thermal regime, treatments resulted in significantly lower induction of ECOD activity and inhibition of MXR activity, suggesting a suppressed metabolism of neonicotinoids and less impaired membrane transport activity in daphnids. Elevated temperature on its own, caused a three-fold rise in ROS levels in control daphnids, while ROS overproduction upon neonicotinoid exposure was less accentuated. Acute exposures to ACE and Thia caused significant decreases also in the reproduction of daphnids, indicating delayed outcomes even at environmentally relevant concentrations. Both the cellular alterations in exposed daphnids and decreases in their reproductive output post exposures evidenced closely similar toxicity patterns and potentials for the two neonicotinoids. While elevated temperature elicited only a shift in baseline cellular alterations evoked by neonicotinoids, it significantly worsened the reproductive performance of daphnids following neonicotinoid exposures.

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AIM: There have been limited prospective investigations of early clinical markers involved in mood regulation and diagnosis change in young patients. This study aimed to evaluate the changes in impulsivity and defence mechanisms in patients with major depressive disorder (MDD) and bipolar disorder (BD) with acute symptoms and remission compared to healthy controls (HC), and possible psychological predictors of diagnosis conversion. METHODS: Seventy-nine young MDD or BD patients and 40 HC were enrolled in a two-year prospective study. A comprehensive clinical interview focused on clinical and psychological evaluation during follow-up visits. The severity of depressive symptoms was evaluated using the Hamilton Depression Rating Scale (HDRS-17), whilst the Young Mania Rating Scale (YMRS) was used for hypo/manic symptoms during each control visit. All patients completed the Defence Style Questionnaire (DSQ-40) and Barratt Impulsiveness Scale (BIS-11). RESULTS: Patients used more immature defences, and had significantly higher total impulsivity scores than controls. BD patients had elevated motor and non-planning impulsivity compared with HC and MDD subjects. Total and non-planning impulsiveness remained elevated in euthymia in BD and MDD compared to HC. There were no statistically significant differences in total defence styles and impulsiveness scores at baseline vs. euthymia in MDD or BD patients groups. Significantly higher dissociation scores at baseline discriminated depressive patients who convert to BD in their diagnosis. CONCLUSIONS: Patients with acute mood symptoms used more frequent immature defences and had significantly higher total impulsivity scores than healthy persons. A lack of differences in total defence styles and impulsiveness between patients with acute symptoms and after reaching euthymia in both MDD and BD groups indicates that they are independent of disease status. Dissociation defence mechanisms may be an early diagnostic indicator of BD.

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Introduction: Although patients with myocardial infarction (MI) history exhibit individual differences, several psychological problems can be observed in these patients. The present study aimed to investigate the correlation between defence mechanisms and other clinical and sociodemographic data in the early period in patients with MI history. Material and methods: Sixty patients diagnosed with MI and hospitalized in the cardiology department were included in the study. The Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and Defence Styles Questionnaire (DSQ) were applied. Results: It was determined that the mean BDI score of the participants was 15.9 ±11.2, and the mean BAI score was 15.98 ±10.9. There was a positive correlation between the depression and immature defence mechanism scores of the patients, and there was a negative correlation between the depression and mature defence mechanism scores of the patients (p = 0.001, r = 0.412; p = 0.005, r = -0.359). A negative correlation was determined between anxiety scores and mature defence mechanism scores (p = 0.002, r = -0. 397). Conclusions: The findings demonstrated that depressive complaints of the post-MI patients increased as the immature defence mechanism score increased, and depressive complaints decreased as the maturity defence mechanism score increased. The correlation between the defence mechanisms adopted by MI patients and depression and anxiety symptoms should not be neglected.

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Protein therapeutics play an important role in controlling the functions and activities of disease-causing proteins in modern medicine. Despite protein therapeutics having several advantages over traditional small-molecule therapeutics, further development has been hindered by drug complexity and delivery issues. However, recent progress in deep learning-based protein structure prediction approaches, such as AlphaFold2, opens new opportunities to exploit the complexity of these macro-biomolecules for highly specialised design to inhibit, regulate or even manipulate specific disease-causing proteins. Anti-CRISPR proteins are small proteins from bacteriophages that counter-defend against the prokaryotic adaptive immunity of CRISPR-Cas systems. They are unique examples of natural protein therapeutics that have been optimized by the host-parasite evolutionary arms race to inhibit a wide variety of host proteins. Here, we show that these anti-CRISPR proteins display diverse inhibition mechanisms through accurate structural prediction and functional analysis. We find that these phage-derived proteins are extremely distinct in structure, some of which have no homologues in the current protein structure domain. Furthermore, we find a novel family of anti-CRISPR proteins which are structurally similar to the recently discovered mechanism of manipulating host proteins through enzymatic activity, rather than through direct inference. Using highly accurate structure prediction, we present a wide variety of protein-manipulating strategies of anti-CRISPR proteins for future protein drug design.

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OBJECTIVE: To explore relationship involving Ego Defence Mechanism, Medication Adherence and Self-Management of patients with type 2 diabetes. METHODS: The cross-sectional co-relational study was conducted at the Government College University, Lahore, Pakistan, from November 2017 to November 2018, and comprised diabetics aged 25-55 years. Other than demographic information, data was collected using the Urdu versions of the Defense Style Questionnaire, the Medication Adherence Scale, and the Diabetic Self-management Questionnaire. Data was analysed using SPSS 22. RESULTS: Of the 150 patients, 75(50%) each were females and males. Mature defence mechanisms, like sublimation, suppression and humour, were significant predictors of self-management (p<0.001), and mature defence mechanism, like sublimation, was a significant predictor of medication adherence (p<0.05). Females were high on neurotic defence mechanism, like pseudo-altruism, compared to the males (p=0.001). CONCLUSIONS: Medication adherence and self-management were found to be dependent on mature defence mechanisms.

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Staphylococcus aureus bacteria are components of physiological biocenosis of skin or mucous membranes in some animals' genera but also they are dangerous opportunistic pathogens responsible for infections of various localization, course or manifestations. Proteins produced by these bacteria destroy tissues, leukocytes and cause haemolysis of erythrocytes. Host organisms respond by defence mechanisms. Production of heat stress proteins (HSPs) is one of defence responses of infected host organism. To evaluate infection and host defence mechanisms some animal models of experimental infection are reported. Use of chick embryo model allows demonstrating adequate differences in staphylococcal virulence depending on the strain genotype. The aim of the study was to examine the changes in heat shock protein HSP70 levels in chick embryo tissues after infection caused by S. aureus strains no. tu2, pa3, ch5, ch10, ch24, and ch25 isolated from chickens. The bacteria were injected directly into fluid of amnion cavity and incubated for 10 days. The mortality of particular chick embryos was reported and the tissues for further analysis were taken every day from day 13 to day 19. The levels of heat stress protein HSP70 were determined by dot-blot method. Results showed that the strains no. ch5, ch24, and ch25 were the most virulent. HSP70 levels increased in all groups of injected embryos at the same time the hatching process was started. The presented study showed that the infected chick embryos were characterized by higher HSP level from 12.3% up to 19.7% compared to the control group. The morphological analysis showed numerous erythrocytes with damaged cell membranes and morphological changes of erythrocytes. Changes in the level of HSP70 protein can be a useful indicator of infection caused by S. aureus bacteria. Additionally, chicken embryo is a helpful research model in studies of pathogenesis of diseases caused by bacteria.

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Genetic polymorphisms are the basis of the natural diversity seen in all life on earth, also in plant-pathogen interactions. Initially, studies on plant-pathogen interaction focused on reporting phenotypic variation in resistance properties and on the identification of underlying major genes. Nowadays, the field of plant-pathogen interactions is moving from focusing on families of single dominant genes involved in gene-for-gene interactions to an understanding of the plant immune system in the context of a much more complex signaling network and quantitative resistance. Simultaneously, studies on pathosystems from the wild and genome analyses advanced, revealing tremendous variation in natural plant populations. It is now imperative to place studies on genetic diversity and evolution of plant-pathogen interactions in the appropriate molecular biological, as well as evolutionary, context.

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Background and objectives: COVID-19 has had a negative effect on mental health across the world's population. Healthcare workers in particular have experienced increased levels of psychological distress, depression and anxiety. Any perceived stress to an individual can provoke psychological defence mechanisms. Using psychoanalytic theory, a defence mechanism is described as an unconscious psychological strategy, with or without resulting behaviour, which aims to reduce or eliminate anxiety arising from unacceptable or potentially harmful stimuli. This paper aims to describe a range of psychological defence mechanisms encountered within colleagues in relation to the COVID-19 pandemic.MethodsUsing the methodology of a case series, specific defence mechanisms are explored with reference to further literature in the field.ResultsThe author has encountered varying psychological defence mechanisms, both within himself and in other members of the multidisciplinary team. These have been illustrated in the attached clinical vignettes, relating to the specific psychological coping mechanisms of; denial, hypochondriasis, altruism, sublimation and humour.ConclusionWe encourage acknowledgement of psychological defence mechanisms and their implications on day to day practice. Whilst defence mechanisms can have a number of negative consequences as described in this article, they also have an important role, particularly in the case of mature defence mechanisms, as protective factors against psychological distress and symptom formation. Deeper understanding of the gold-standard hierarchical organisation of defence mechanisms could help increase utilisation of specific therapeutic interventions for enhancing changes from immature to mature defensive responses to stressful experiences as the COVID-19 pandemic progresses.(AU)

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BACKGROUND: Existing research on nursing students' preceptorship experiences focusses mainly on conscious and rational behaviour, evidencing experiences of personal and professional development. This study argues that the exploration of their unconscious experiences could add important information towards an in-depth understanding of their role identity during this experience. OBJECTIVE: The research objective was to describe the unconscious role identity of nursing students during their preceptorship from a systems psychodynamic stance. DESIGN: A qualitative design, a collective case study and hermeneutic phenomenology were utilised as methodologies. SETTING: Set in the School of Nursing of a Canadian University, the research focussed on students in the fourth year Consolidation in Nursing Practice Course. PARTICIPANTS: The sample included 41 nursing students, 37 females, 22-28 years of age. FINDINGS: The manifesting themes were high levels of anxiety, defensive structures, boundary and authority matters, and role dynamics. The nursing students experienced high levels and different kinds of anxiety, which they defended against using introjections, projections and regression to their child ego state. They experienced the preceptorship as being in a middle position between past and future as well as between knowing and not knowing. The discussion was presented in relation to the macro (organisational), meso (group), and micro (individual) levels. CONCLUSIONS: Unconsciously, the nursing students experienced difficulty in effectively taking up their professional role. They defended against their discomfort by splitting their experiences into what they introjected and projected. They introjected incompetence in coping with the emotional demands of the role and projected their anger onto authority figures. Their professional role identity got stuck in a de-authorised position where they could survive but not develop their selves in their new role. These experiences inhibited their authenticity and learning ability.

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Host plant defence mechanisms (resistance and tolerance) and plant nutrition are two of the most widely proposed components for the control of hemiparasitic weeds of the genus Striga in tropical cereal production systems. Neither of the two components alone is effective enough to prevent parasitism and concomitant crop losses. This review explores the potential of improved plant nutrition, being the chemical constituent of soil fertility, to fortify the expression of plant inherent resistance and tolerance against Striga. Beyond reviewing advances in parasitic plant research, we assess relevant insights from phytopathology and plant physiology in the broader sense to identify opportunities and knowledge gaps and to develop the way forward regarding research and development of combining genetics and plant nutrition for the durable control of Striga.

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BACKGROUND AND OBJECTIVES: COVID-19 has had a negative effect on mental health across the world's population. Healthcare workers in particular have experienced increased levels of psychological distress, depression and anxiety. Any perceived stress to an individual can provoke psychological defence mechanisms. Using psychoanalytic theory, a defence mechanism is described as an unconscious psychological strategy, with or without resulting behaviour, which aims to reduce or eliminate anxiety arising from unacceptable or potentially harmful stimuli. This paper aims to describe a range of psychological defence mechanisms encountered within colleagues in relation to the COVID-19 pandemic. METHODS: Using the methodology of a case series, specific defence mechanisms are explored with reference to further literature in the field. RESULTS: The author has encountered varying psychological defence mechanisms, both within himself and in other members of the multidisciplinary team. These have been illustrated in the attached clinical vignettes, relating to the specific psychological coping mechanisms of; denial, hypochondriasis, altruism, sublimation and humour. CONCLUSION: We encourage acknowledgement of psychological defence mechanisms and their implications on day to day practice. Whilst defence mechanisms can have a number of negative consequences as described in this article, they also have an important role, particularly in the case of mature defence mechanisms, as protective factors against psychological distress and symptom formation. Deeper understanding of the gold-standard hierarchical organisation of defence mechanisms could help increase utilisation of specific therapeutic interventions for enhancing changes from immature to mature defensive responses to stressful experiences as the COVID-19 pandemic progresses.

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OBJECTIVE: To examine the association between reflective function and global functionality in borderline personality disorder (BPD) patients, controlling for symptomatology and defensive style. METHOD: Thirty-nine female inpatients were evaluated employing a sociodemographic questionnaire, the Structured Clinical Interview for Personality Disorders-II (SCID-II), the Self-Reporting Questionnaire (SRQ-20), the Reflective Functioning Questionnaire (RFQ), the Defence Style Questionnaire-40 (DSQ-40) and the Global Assessment of Functioning (GAF). RESULTS: Functionality was inversely associated with the reflective function uncertainty score (-.458; p < .01) and neurotic defences (-.335; p < .05). Symptom severity (SRQ-20) was associated with the use of immature defences (-.445; p < .01). The association between functionality and the reflective function uncertainty score remained significant, even when controlled for symptoms and defensive style (p = .002). CONCLUSION: The ability to mentalise seems to play a central and somehow independent role in BPD psychopathology.

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The beneficial associations between Arachis hypogaea L. (peanut) and fluorescent Pseudomonas species have been poorly explored despite their predominance in the peanut rhizosphere. The present study explores the mutually beneficial interactions between peanut roots and P. aeruginosa P4 (P4) in terms of their impact on plant growth, defence physiology and the root-rhizobacterial interface. The efficient phosphate solubilizer P4 exhibited biocontrol abilities, including the production of siderophores, pyocyanin, indole-3-acetic acid and hydrogen cyanide. The bacterization of peanut seeds with multi-potential P4 significantly enhanced in vitro seed germination and seedling vigour. Under sand-based gnotobiotic (10 days post-inoculation) and sterile soil-based cultivation systems (30 days post-inoculation), sustained P4 colonization enhanced the peanut root length and dry plant biomass. The subsequent increase in catalase, polyphenol oxidase and phenylalanine ammonia lyase activities with increased phenolic contents in the peanut roots and shoots suggested the systemic priming of defences. Consequently, the altered root exudate composition caused enhanced chemo-attraction towards P4 itself and the symbiotic N2-fixing Bradyrhizobium strain. Co-inoculating peanuts with P4 and Bradyrhizobium confirmed the improved total bacterial colonization (∼2 fold) of the root tip, with the successful co-localization of both, as substantiated by scanning electron microscopy. Collectively, the peanut-P4 association could potentially model the beneficial Pseudomonas-driven multi-trophic rhizosphere benefits, emphasizing the plausible role of non-rhizobium PGPR in promoting N2 fixation.

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A hypothesis that simultaneous targeting cancer-related carbonic anhydrase hCA IX and hCA XII isoforms (whose overexpression is a cancer cell's defence mechanism against hypoxia) along with thioredoxin reductase (overexpressed in cancers as a defence against oxidative stress) may lead to synergistic antiproliferative effects was confirmed by testing combinations of the two inhibitor classes against pancreatic cancer cells (PANC-1). Combining both pharmacophoric motifs within one molecule led to a sharp increase of cytotoxicity. This preliminary observation sets the ground for a fundamentally new approach to anticancer agent design.

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