Chest pain while gardening: a Stanford type A dissection involving the aortic root extending into the iliac arteries-an uncommon and potentially catastrophic disease process

BACKGROUND: An aortic dissection is an uncommon and potentially catastrophic disease process that carries with it a high morbidity and mortality. The inciting event is a tear in the intimal lining of the aorta. This allows passage of blood through the tear and into the aortic media, resulting in the creation of a false lumen. CASE PRESENTATION: We describe the case of a 71-year-old male with a history of hypertension that suffered a Stanford type A dissection with an intimal flap beginning at the level of the aortic root and extending into the bilateral iliac arteries. His clinical presentation was further complicated by shock, cardiac tamponade, severe coagulopathy, an ischemic right lower extremity, infarction of his thoracic spinal cord, and subacute infarcts secondary to malperfusion and embolic disease. Despite maximal intervention, the patient continued to clinically decline and ultimately died on day 5. CONCLUSION: The clinical presentation of an acute aortic dissection is often atypical and mimics other common disease processes. The signs and symptoms largely depend on the extent of the aortic dissection and the presence or absence of malperfusion. With a mortality increasing by 1-2% for every hour until definitive treatment, early recognition and prompt operative intervention are crucial for patient survival

A Psychometric Comparison of Psychological Inflexibility Measures: Discriminant Validity and Item Performance

Psychological inflexibility is a rigid behavioral pattern that interferes with engagement in personally meaningful activities; it is the hypothesized root of suffering in acceptance and commitment therapy (ACT). Thus, the quality of its measurement affects the research, theory, and practice of ACT. The current study aimed to evaluate the discriminant validity and item performance of four measures of psychological inflexibility: the Acceptance and Action Questionnaire—II (AAQ-II), a revised version of the AAC-II (AAQ-3), the Brief Experiential Avoidance Questionnaire (BEAQ), and the Comprehensive assessment of Acceptance and Commitment Therapy processes (CompACT). We analyzed data from community (n = 253), student (n = 261), and treatment-seeking samples (n = 140) using exploratory factor analysis and multigroup graded-response models. The CompACT had the strongest discriminant validity followed by the AAQ-3, whereas items in the CompACT Behavioral Awareness and Valued Action subscales performed most consistently across groups. No single measure emerged as clearly superior to others; rather, appropriate selection of measures depends on the goals and context of assessment. Scientific and clinical implications are discussed

A Pilot Randomized Controlled Trial of Online-Delivered ACT-Enhanced Behavior Therapy for Trichotillomania in Adolescents

Treatment of adolescent trichotillomania is understudied, and treatment providers are difficult to find. In this pilot study, we compared ACT-enhanced behavior therapy to a waitlist, with treatment delivered over Zoom, to 28 adolescents who met criteria for trichotillomania. This study partially occurred during the COVID-19 pandemic. A detailed description of the treatment protocol is provided for ACT-enhanced behavior therapy adapted to a Zoom format for adolescents. Pretreatment assessments were completed over Zoom by an assessor unaware of study condition; pretreatment and posttreatment questionnaires were completed online. Results indicated that therapy was delivered with fidelity and competence over Zoom, with 100% session completion. Adolescents reported that pulling severity decreased significantly more in the treatment condition than waitlist. No differences were seen in other adolescent or parent-reported pulling severity or distress. However, significant medium to large within-condition effect sizes were observed in the treatment condition. Medium effect size changes were seen in the treatment group on a measure of trichotillomania-related psychological flexibility, and a small effect size was seen for psychological distress. Overall, pilot results provide preliminary support for ACT-enhanced behavior therapy, delivered over Zoom, for adolescent trichotillomania, indicating the need for a fully powered confirmatory efficacy trial

Smooth Muscle Stiffness Sensitivity is Driven by Soluble and Insoluble ECM Chemistry

Smooth muscle cell (SMC) invasion into plaques and subsequent proliferation is a major factor in the progression of atherosclerosis. During disease progression, SMCs experience major changes in their microenvironment, such as what integrin-binding sites are exposed, the portfolio of soluble factors available, and the elasticity and modulus of the surrounding vessel wall. We have developed a hydrogel biomaterial platform to examine the combined effect of these changes on SMC phenotype. We were particularly interested in how the chemical microenvironment affected the ability of SMCs to sense and respond to modulus. To our surprise, we observed that integrin binding and soluble factors are major drivers of several critical SMC behaviors, such as motility, proliferation, invasion, and differentiation marker expres- sion, and these factors modulated the effect of stiffness on proliferation and migration. Overall, modulus only modestly affected behaviors other than proliferation, relative to integrin binding and soluble factors. Surprisingly, patho- logical behaviors (proliferation, motility) are not inversely related to SMC marker expression, in direct conflict with previous studies on substrates coupled with single extracel- lular matrix (ECM) proteins. A high-throughput bead-based ELISA approach and inhibitor studies revealed that differ- entiation marker expression is mediated chiefly via focal adhesion kinase (FAK) signaling, and we propose that integrin binding and FAK drive the transition from a migratory to a proliferative phenotype. We emphasize the importance of increasing the complexity of in vitro testing platforms to capture these subtleties in cell phenotypes and signaling, in order to better recapitulate important features of in vivo disease and elucidate potential context-dependent therapeutic targets

Symbiotic Nitrogen Fixation and the Challenges to Its Extension to Nonlegumes

Access to fixed or available forms of nitrogen limits the productivity of crop plants and thus food production. Nitrogenous fertilizer production currently represents a significant expense for the efficient growth of various crops in the developed world. There are significant potential gains to be had from reducing dependence on nitrogenous fertilizers in agriculture in the developed world and in developing countries, and there is significant interest in research on biological nitrogen fixation and prospects for increasing its importance in an agricultural setting. Biological nitrogen fixation is the conversion of atmospheric N2 to NH3, a form that can be used by plants. However, the process is restricted to bacteria and archaea and does not occur in eukaryotes. Symbiotic nitrogen fixation is part of a mutualistic relationship in which plants provide a niche and fixed carbon to bacteria in exchange for fixed nitrogen. This process is restricted mainly to legumes in agricultural systems, and there is considerable interest in exploring whether similar symbioses can be developed in nonlegumes, which produce the bulk of human food. We are at a juncture at which the fundamental understanding of biological nitrogen fixation has matured to a level that we can think about engineering symbiotic relationships using synthetic biology approaches. This minireview highlights the fundamental advances in our understanding of biological nitrogen fixation in the context of a blueprint for expanding symbiotic nitrogen fixation to a greater diversity of crop plants through synthetic biology.Biotechnology and Biological Sciences Research Council (Great Britain) (Grants BB/L011484/1 and BB/L011476/1)National Science Foundation (U.S.) (Grant 1331098

Polydnavirus genomes reflect their dual roles as mutualists and pathogens

AbstractSymbionts often exhibit significant reductions in genome complexity while pathogens often exhibit increased complexity through acquisition and diversification of virulence determinants. A few organisms have evolved complex life cycles in which they interact as symbionts with one host and pathogens with another. How the predicted and opposing influences of symbiosis and pathogenesis affect genome evolution in such instances, however, is unclear. The Polydnaviridae is a family of double-stranded (ds) DNA viruses associated with parasitoid wasps that parasitize other insects. Polydnaviruses (PDVs) only replicate in wasps but infect and cause severe disease in parasitized hosts. This disease is essential for survival of the parasitoid's offspring. Thus, a true mutualism exists between PDVs and wasps as viral transmission depends on parasitoid survival and parasitoid survival depends on viral infection of the wasp's host. To investigate how life cycle and ancestry affect PDVs, we compared the genomes of Campoletis sonorensis ichnovirus (CsIV) and Microplitis demolitor bracovirus (MdBV). CsIV and MdBV have no direct common ancestor, yet their encapsidated genomes share several features including segmentation, diversification of virulence genes into families, and the absence of genes required for replication. In contrast, CsIV and MdBV share few genes expressed in parasitized hosts. We conclude that the similar organizational features of PDV genomes reflect their shared life cycle but that PDVs associated with ichneumonid and braconid wasps have likely evolved different strategies to cause disease in the wasp's host and promote parasitoid survival

New Frontiers for Organismal Biology

Understanding how complex organisms function as integrated units that constantly interact with their environment is a long-standing challenge in biology. To address this challenge, organismal biology reveals general organizing principles of physiological systems and behavior—in particular, in complex multicellular animals. Organismal biology also focuses on the role of individual variability in the evolutionary maintenance of diversity. To broadly advance these frontiers, cross-compatibility of experimental designs, methodological approaches, and data interpretation pipelines represents a key prerequisite. It is now possible to rapidly and systematically analyze complete genomes to elucidate genetic variation associated with traits and conditions that define individuals, populations, and species. However, genetic variation alone does not explain the varied individual physiology and behavior of complex organisms. We propose that such emergent properties of complex organisms can best be explained through a renewed emphasis on the context and life-history dependence of individual phenotypes to complement genetic data.Organismic and Evolutionary Biolog

An Analysis of the Systemic Risks Posed by Fannie Mae and Freddie Mac and an Evaluation of the Policy Options for Reducing those Risks

Fannie Mae and Freddie Mac are government-sponsored enterprises that are central players in U.S. secondary mortgage markets. Over the past decade, these institutions have amassed enormous mortgage- and non-mortgage-oriented investment portfolios that pose significant interest-rate risks to the companies and a systemic risk to the financial system. This paper describes the nature of these risks and systemic concerns and then evaluates several policy options for reducing the institutions’ investment portfolios. We conclude that limits on portfolio size (assets or liabilities) would be the most desirable approach to mitigating the systemic risk posed by Fannie Mae and Freddie Mac

Building robust, practicable counterfactuals and scenarios to evaluate the impact of species conservation interventions using inferential approaches

Robust evaluation of the impact of biodiversity conservation actions is important not only for ensuring that conservation strategies are effective and maximise return on investment, but also to identify and celebrate successful conservation strategies. This evaluation can be retrospective (comparing the current situation to a counterfactual scenario) or forward-looking (comparing future scenarios with or without conservation). However, assessment of impact using experimental or quasi-experimental designs is typically difficult in conservation, so rigorous inferential approaches are required. Inferential assessment of impact is a key part of the new IUCN Green Status of Species, which greatly amplifies the need for standardised and practical species impact evaluation methods. Here, we use the Green Status of Species method as a base to review how inferential methods can be used to evaluate conservation impact at the species level. We identify three key components of the inferential impact evaluation process—estimation of scenario outcomes, selection of baseline scenario, and frame of reference—and explain, with examples, how to reduce the subjectivity of these steps. We propose a step-by-step guide, incorporating these principles, that can be used to infer scenario outcomes in order to evaluate past and future conservation impact in a wide range of situations, not just Green Status of Species assessments. We recommend that future non-experimental conservation interventions facilitate the process of evaluating impact by identifying the variable(s) that will be used to measure impact at the design stage, and by using conceptual models to help choose conservation actions most likely to have the desired impact