123I-iomazenil whole-body imaging to detect hepatic carboxylesterase drug-metabolizing enzyme activity

OBJECTIVES: Drugs are mainly metabolized by hepatic enzymes, the activity of which can differ between individuals. Although it is ideal to measure the hepatic clearance of liver-targeted drugs in individualized medicine, blood enzyme tests typically measure metabolic drug clearance in the entire body, and not just in the liver. We investigated whether I-iomazenil imaging can directly assess and quantify the activity of hepatic drug-metabolizing enzymes. MATERIALS AND METHODS: Hepatic enzymes that metabolize I-iomazenil were identified by thin-layer chromatography in mouse liver homogenates with bis(4-nitrophenyl) phosphate (BNPP) inhibitor for carboxylesterase enzymes and nicotinamide adenine dinucleotide phosphate (NADPH) generator for cytochrome P450 enzymes. Whole-body images of mice were acquired using I-iomazenil with and without BNPP, and the distribution was also obtained. The metabolism of I-iomazenil in the blood, liver, gall bladder, and bladder was investigated by thin-layer chromatography. RESULTS: From the in-vitro metabolism of I-iomazenil using BNPP, the enzyme converting I-iomazenil to I-R-COOH was identified as carboxylesterase, and that converting I-iomazenil to M2 was identified as cytochrome P450 in experiments with and without an NADPH generator. The biological distribution and whole-body imaging showed increased accumulation in the liver of mice administered BNPP compared with normal mice, but decreased levels in the gall bladder and small intestine. The main fraction in bile and urine was I-R-COOH, with two unknown metabolites (M1 and M2), I, and I-iomazenil also being present. CONCLUSION: I-iomazenil whole-body imaging has good possibility of direct measurement of hepatic carboxylesterase activity as accumulation of I-R-COOH in the gall bladder through bile and in the bladder through urine

Variable Levels Of Drift In Tunicate Cardiopharyngeal Gene Regulatory Elements

Background: Mutations in gene regulatory networks often lead to genetic divergence without impacting gene expression or developmental patterning. The rules governing this process of developmental systems drift, including the variable impact of selective constraints on different nodes in a gene regulatory network, remain poorly delineated. Results: Here we examine developmental systems drift within the cardiopharyngeal gene regulatory networks of two tunicate species, Corella inflata and Ciona robusta. Cross-species analysis of regulatory elements suggests that trans-regulatory architecture is largely conserved between these highly divergent species. In contrast, cis-regulatory elements within this network exhibit distinct levels of conservation. In particular, while most of the regulatory elements we analyzed showed extensive rearrangements of functional binding sites, the enhancer for the cardiopharyngeal transcription factor FoxF is remarkably well-conserved. Even minor alterations in spacing between binding sites lead to loss of FoxF enhancer function, suggesting that bound trans-factors form position-dependent complexes. Conclusions: Our findings reveal heterogeneous levels of divergence across cardiopharyngeal cis-regulatory elements. These distinct levels of divergence presumably reflect constraints that are not clearly associated with gene function or position within the regulatory network. Thus, levels of cis-regulatory divergence or drift appear to be governed by distinct structural constraints that will be difficult to predict based on network architecture

Use of Biosensors as Alternatives to Current Regulatory Methods for Marine Biotoxins

Marine toxins are currently monitored by means of a bioassay that requires the use of many mice, which poses a technical and ethical problem in many countries. With the exception of domoic acid, there is a legal requirement for the presence of other toxins (yessotoxin, saxitoxin and analogs, okadaic acid and analogs, pectenotoxins and azaspiracids) in seafood to be controlled by bioassay, but other toxins, such as palytoxin, cyclic imines, ciguatera and tetrodotoxin are potentially present in European food and there are no legal requirements or technical approaches available to identify their presence. The need for alternative methods to the bioassay is clearly important, and biosensors have become in recent years a feasible alternative to animal sacrifice. This review will discuss the advantages and disadvantages of using biosensors as alternatives to animal assays for marine toxins, with particular focus on surface plasmon resonance (SPR) technology

Prognostic Implications of Fractional Flow Reserve After Coronary Stenting:A Systematic Review and Meta-analysis

IMPORTANCE: Fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is generally considered to reflect residual disease. Yet the clinical relevance of post-PCI FFR after drug-eluting stent (DES) implantation remains unclear. OBJECTIVE: To evaluate the clinical relevance of post-PCI FFR measurement after DES implantation. DATA SOURCES: MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched for relevant published articles from inception to June 18, 2022. STUDY SELECTION: Published articles that reported post-PCI FFR after DES implantation and its association with clinical outcomes were included. DATA EXTRACTION AND SYNTHESIS: Patient-level data were collected from the corresponding authors of 17 cohorts using a standardized spreadsheet. Meta-estimates for primary and secondary outcomes were analyzed per patient and using mixed-effects Cox proportional hazard regression with registry identifiers included as a random effect. All processes followed the Preferred Reporting Items for Systematic Review and Meta-analysis of Individual Participant Data. MAIN OUTCOMES AND MEASURES: The primary outcome was target vessel failure (TVF) at 2 years, a composite of cardiac death, target vessel myocardial infarction (TVMI), and target vessel revascularization (TVR). The secondary outcome was a composite of cardiac death or TVMI at 2 years. RESULTS: Of 2268 articles identified, 29 studies met selection criteria. Of these, 28 articles from 17 cohorts provided data, including a total of 5277 patients with 5869 vessels who underwent FFR measurement after DES implantation. Mean (SD) age was 64.4 (10.1) years and 4141 patients (78.5%) were men. Median (IQR) post-PCI FFR was 0.89 (0.84-0.94) and 690 vessels (11.8%) had a post-PCI FFR of 0.80 or below. The cumulative incidence of TVF was 340 patients (7.2%), with cardiac death or TVMI occurring in 111 patients (2.4%) at 2 years. Lower post-PCI FFR significantly increased the risk of TVF (adjusted hazard ratio [HR] per 0.01 FFR decrease, 1.04; 95% CI, 1.02-1.05; P < .001). The risk of cardiac death or MI also increased inversely with post-PCI FFR (adjusted HR, 1.03; 95% CI, 1.00-1.07, P = .049). These associations were consistent regardless of age, sex, the presence of hypertension or diabetes, and clinical diagnosis. CONCLUSIONS AND RELEVANCE: Reduced FFR after DES implantation was common and associated with the risks of TVF and of cardiac death or TVMI. These results indicate the prognostic value of post-PCI physiologic assessment after DES implantation

Galectin-4 Controls Intestinal Inflammation by Selective Regulation of Peripheral and Mucosal T Cell Apoptosis and Cell Cycle

Galectin-4 is a carbohydrate-binding protein belonging to the galectin family. Here we provide novel evidence that galectin-4 is selectively expressed and secreted by intestinal epithelial cells and binds potently to activated peripheral and mucosal lamina propria T-cells at the CD3 epitope. The carbohydrate-dependent binding of galectin-4 at the CD3 epitope is fully functional and inhibited T cell activation, cycling and expansion. Galectin-4 induced apoptosis of activated peripheral and mucosal lamina propria T cells via calpain-, but not caspase-dependent, pathways. Providing further evidence for its important role in regulating T cell function, galectin-4 blockade by antisense oligonucleotides reduced TNF-alpha inhibitor induced T cell death. Furthermore, in T cells, galectin-4 reduced pro-inflammatory cytokine secretion including IL-17. In a model of experimental colitis, galectin-4 ameliorated mucosal inflammation, induced apoptosis of mucosal T-cells and decreased the secretion of pro-inflammatory cytokines. Our results show that galectin-4 plays a unique role in the intestine and assign a novel role of this protein in controlling intestinal inflammation by a selective induction of T cell apoptosis and cell cycle restriction. Conclusively, after defining its biological role, we propose Galectin-4 is a novel anti-inflammatory agent that could be therapeutically effective in diseases with a disturbed T cell expansion and apoptosis such as inflammatory bowel disease

A narrative review on the similarities and dissimilarities between myalgic encephalomyelitis/chronic fatigue syndrome (me/cfs) and sickness behavior

It is of importance whether myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a variant of sickness behavior. The latter is induced by acute infections/injury being principally mediated through proinflammatory cytokines. Sickness is a beneficial behavioral response that serves to enhance recovery, conserves energy and plays a role in the resolution of inflammation. There are behavioral/symptomatic similarities (for example, fatigue, malaise, hyperalgesia) and dissimilarities (gastrointestinal symptoms, anorexia and weight loss) between sickness and ME/CFS. While sickness is an adaptive response induced by proinflammatory cytokines, ME/CFS is a chronic, disabling disorder, where the pathophysiology is related to activation of immunoinflammatory and oxidative pathways and autoimmune responses. While sickness behavior is a state of energy conservation, which plays a role in combating pathogens, ME/CFS is a chronic disease underpinned by a state of energy depletion. While sickness is an acute response to infection/injury, the trigger factors in ME/CFS are less well defined and encompass acute and chronic infections, as well as inflammatory or autoimmune diseases. It is concluded that sickness behavior and ME/CFS are two different conditions

Gut mucosal DAMPs in IBD: From mechanisms to therapeutic implications

Endogenous damage-associated molecular patterns (DAMPs) are released during tissue damage and have increasingly recognized roles in the etiology of many human diseases. The inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn’s disease (CD), are immune-mediated conditions where high levels of DAMPs are observed. DAMPs such as calprotectin (S100A8/9) have an established clinical role as a biomarker in IBD. In this review, we use IBD as an archetypal common chronic inflammatory disease to focus on the conceptual and evidential importance of DAMPs in pathogenesis and why DAMPs represent an entirely new class of targets for clinical translation. </p