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Frontiers in Genetics 2023The relationship between insect pathogenic fungi and their insect hosts is a classic example of a co-evolutionary arms race between pathogen and target host: parasites... (Review)
Review
The relationship between insect pathogenic fungi and their insect hosts is a classic example of a co-evolutionary arms race between pathogen and target host: parasites evolve towards mechanisms that increase their advantage over the host, and the host increasingly strengthens its defenses. The present review summarizes the literature data describing the direct and indirect role of lipids as an important defense mechanism during fungal infection. Insect defense mechanisms comprise anatomical and physiological barriers, and cellular and humoral response mechanisms. The entomopathogenic fungi have the unique ability to digest the insect cuticle by producing hydrolytic enzymes with chitin-, lipo- and proteolytic activity; besides the oral tract, cuticle pays the way for fungal entry within the host. The key factor in insect resistance to fungal infection is the presence of certain types of lipids (free fatty acids, waxes or hydrocarbons) which can promote or inhibit fungal attachment to cuticle, and might also have antifungal activity. Lipids are considered as an important source of energy, and as triglycerides are stored in the fat body, a structure analogous to the liver and adipose tissue in vertebrates. In addition, the fat body plays a key role in innate humoral immunity by producing a range of bactericidal proteins and polypeptides, one of which is lysozyme. Energy derived from lipid metabolism is used by hemocytes to migrate to the site of fungal infection, and for phagocytosis, nodulation and encapsulation. One polyunsaturated fatty acid, arachidonic acid, is used in the synthesis of eicosanoids, which play several crucial roles in insect physiology and immunology. Apolipoprotein III is important compound with antifungal activity, which can modulate insect cellular response and is considered as important signal molecule.
PubMed: 37359377
DOI: 10.3389/fgene.2023.1183659 -
Med (New York, N.Y.) May 2021Radix and Harris discuss the current state of transgender health and the challenges to equitable medical access experienced by transgender and gender-diverse patients....
Radix and Harris discuss the current state of transgender health and the challenges to equitable medical access experienced by transgender and gender-diverse patients. Transgender medicine has evolved significantly since the first clinical practice guidelines were developed more than 40 years ago, but important research gaps exist.
Topics: Gender Identity; Humans; Medicine; Plant Roots; Transgender Persons; Transsexualism
PubMed: 35590227
DOI: 10.1016/j.medj.2021.04.025 -
Parasites & Vectors Apr 2019Mosquito-borne diseases are associated with major global health burdens. Aedes spp. and Culex spp. are primarily responsible for the transmission of the most medically... (Review)
Review
Mosquito-borne diseases are associated with major global health burdens. Aedes spp. and Culex spp. are primarily responsible for the transmission of the most medically important mosquito-borne viruses, including dengue virus, West Nile virus and Zika virus. Despite the burden of these pathogens on human populations, the interactions between viruses and their mosquito hosts remain enigmatic. Viruses enter the midgut of a mosquito following the mosquito's ingestion of a viremic blood meal. During infection, virus recognition by the mosquito host triggers their antiviral defense mechanism. Of these host defenses, activation of the RNAi pathway is the main antiviral mechanism, leading to the degradation of viral RNA, thereby inhibiting viral replication and promoting viral clearance. However, whilst antiviral host defense mechanisms limit viral replication, the mosquito immune system is unable to effectively clear the virus. As such, these viruses can establish persistent infection with little or no fitness cost to the mosquito vector, ensuring life-long transmission to humans. Understanding of the mosquito innate immune response enables the discovery of novel antivectorial strategies to block human transmission. This review provides an updated and concise summary of recent studies on mosquito antiviral immune responses, which is a key determinant for successful virus transmission. In addition, we will also discuss the factors that may contribute to persistent infection in mosquito hosts. Finally, we will discuss current mosquito transmission-blocking strategies that utilize genetically modified mosquitoes and Wolbachia-infected mosquitoes for resistance to pathogens.
Topics: Animals; Culicidae; Humans; Immunity, Innate; Mosquito Control; RNA Interference; RNA, Viral
PubMed: 30975197
DOI: 10.1186/s13071-019-3433-8 -
BMJ Open Respiratory Research Jul 2023Epidemiological and clinical studies have indicated an association between particulate matter (PM) exposure and acute and chronic pulmonary inflammation, which may be... (Review)
Review
Epidemiological and clinical studies have indicated an association between particulate matter (PM) exposure and acute and chronic pulmonary inflammation, which may be registered as increased mortality and morbidity. Despite the increasing evidence, the pathophysiology mechanism of these PMs is still not fully characterised. Pulmonary alveolar macrophages (PAMs), as a predominant cell in the lung, play a critically important role in these pathological mechanisms. Toxin exposure triggers events associated with macrophage activation, including oxidative stress, acute damage, tissue disruption, remodelling and fibrosis. Targeting macrophage may potentially be employed to treat these types of lung inflammation without affecting the natural immune response to bacterial infections. Biological toxins, their sources of exposure, physical and other properties, and their effects on the individuals are summarised in this article. Inhaled particulates from air pollution and toxic gases containing chemicals can interact with alveolar epithelial cells and immune cells in the airways. PAMs can sense ambient pollutants and be stimulated, triggering cellular signalling pathways. These cells are highly adaptable and can change their function and phenotype in response to inhaled agents. PAMs also have the ability to polarise and undergo plasticity in response to tissue damage, while maintaining resistance to exposure to inhaled agents.
Topics: Humans; Macrophages, Alveolar; Air Pollution; Gases; Lung; Defense Mechanisms
PubMed: 37479504
DOI: 10.1136/bmjresp-2022-001589 -
Obesity (Silver Spring, Md.) Dec 2021Weight stigma is associated with impaired health, attributed in part to reductions in health-promoting behaviors. This review analyzed evidence of the association... (Review)
Review
OBJECTIVE
Weight stigma is associated with impaired health, attributed in part to reductions in health-promoting behaviors. This review analyzed evidence of the association between weight stigma and physical activity (PA) in adults and youth.
METHODS
Three databases were searched for terms related to weight stigma and PA. Eligible studies reported the quantitative association between at least one measure of weight stigma and one behavioral measure of PA.
RESULTS
A total of 38 studies met eligibility criteria. Of the 29 studies of adults, 3 used objective PA measures, and 79% used an observational, cross-sectional design. Findings of the relationship between weight stigma and PA were mixed. Everyday weight discrimination and internalizing weight stigma were associated with reduced PA in most studies. Several studies found indirect, and not direct, effects of weight stigma on PA when analyses included other individual-level factors. In the nine studies of youth, two used objective PA measures, all were observational, and only one study was longitudinal. Most youth studies found a relationship between weight-based teasing and reduced PA.
CONCLUSIONS
Weight teasing, everyday discrimination, and internalization were associated with reduced PA. However, associations were inconsistent and often indirect. Future studies should include objective PA measures with larger samples and longitudinal assessments.
Topics: Adolescent; Adult; Cross-Sectional Studies; Databases, Factual; Defense Mechanisms; Exercise; Humans; Social Stigma; Weight Prejudice
PubMed: 34747131
DOI: 10.1002/oby.23274 -
International Journal of Environmental... Oct 2022Emotion regulation is an important aspect of psychological functioning that influences subjective experience and moderates emotional responses throughout the lifetime....
Emotion regulation is an important aspect of psychological functioning that influences subjective experience and moderates emotional responses throughout the lifetime. Adaptive responses to stressful life events depend on the positive interaction between explicit and implicit emotion regulation strategies, such as mindfulness and defense mechanisms. This study demonstrates how these emotion regulation strategies predict psychological health during the early phase of the COVID-19 pandemic. A convenience sample of 6385 subjects, recruited via snowball sampling on various social media platforms, responded to an online survey assessing psychological reaction to social restrictions imposed to limit the spread of COVID-19 in Italy. Psychological distress, post-traumatic stress symptoms, mindfulness, and defense mechanisms were assessed using SCL-90, IES-R, MAAS, and DMRS-30-SR, respectively. Higher mindfulness was significantly associated with higher overall defensive maturity and a greater use of high-adaptive defenses ( < 0.0001). Both mindfulness and defense mechanisms acted as good predictors of psychological health (R = 0.541) and posttraumatic symptoms (R = 0.332), confirming the role of emotion regulation in protecting against maladaptive responses to stressful situations.
Topics: COVID-19; Defense Mechanisms; Emotional Regulation; Humans; Mindfulness; Pandemics; Psychological Distress
PubMed: 36231993
DOI: 10.3390/ijerph191912690 -
Research in Psychotherapy (Milano) Dec 2023Defense mechanisms are adaptative processes that are related to mental health and psychological functioning and may play an important role in adaptation to distress, as...
Defense mechanisms are adaptative processes that are related to mental health and psychological functioning and may play an important role in adaptation to distress, as well as in mental health interventions. The present study aimed to compare the use of defense mechanisms and their relationship to mental health symptoms across six countries. In a large-scale descriptive study, we collected data from community- based individuals (N=19,860) in the United States, Australia, Canada, Germany, Italy, and the United Kingdom about the use of defense mechanisms and experienced mental health symptoms during the early phase of the pandemic. We found that the use of defense mechanism categories was similar across countries. Moreover, lower defensive functioning, specifically, neurotic and immature defenses were related to experiencing higher distress across countries, whereas mature defenses were generally inversely related to symptoms. Furthermore, these findings were relatively similar across the six countries. Cross-cultural research on defense mechanisms and mental health has important clinical implications. Our results are consistent with the goal of promoting more adaptive defensive functioning to increase psychological well-being and mitigate the detrimental impact of situational stress.
PubMed: 38226792
DOI: 10.4081/ripppo.2023.729 -
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 -
AMA Journal of Ethics Jul 2021Tension between naming to render an important kind of suffering among transgender people more visible and avoiding pathologizing experiences of transgender people in a...
Tension between naming to render an important kind of suffering among transgender people more visible and avoiding pathologizing experiences of transgender people in a gender-binary world can be keenly felt among patients seeking gender-affirming services. This article suggests why clinical "verification" of a patient's need for gender-affirming care is likely less important than clinicians' expressions of empathy and respect for patients' autonomy. This article also suggests that fostering transgender patients' sense of agency should be prioritized.
Topics: Emotions; Gender Dysphoria; Gender Identity; Humans; Transgender Persons; Transsexualism
PubMed: 34351266
DOI: 10.1001/amajethics.2021.557 -
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