Publications by authors named "David Moons"

Acetyl fentanyl (N-[1-phenethylpiperidin-4-yl]-N-phenylacetamide) is a potent opioid analgesic with no medicinal uses. We report deaths between 2016 and 2017 at the Medical Examiner's Office in Detroit, MI where acetyl fentanyl was found in the decedent's blood and compare them to previously published deaths between 2015 and 2016. The recent cases (cohort B) had a mean acetyl fentanyl concentration of 0.

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We investigated whether intrapancreatic coagulation, with deposition of the fibrinogen-γ dimer (Fib-γD) and hypoxia, affect the severity of acute pancreatitis (AP) in mice. Pancreata of mice with AP induced by administration of cerulein or by L-arginine, or from patients with pancreatitis, had increased deposition of Fib-γD compared with control pancreata. Heparin administration protected mice from cerulein-induced AP and prevented Fib-γD formation.

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Objectives: To determine whether contrast-enhanced sonographic quantitative perfusion parameters can detect bowel wall fibrosis in the setting of mixed inflammatory and fibrotic lesions in a Crohn disease animal model.

Methods: This study was approved by the institutional Committee on the Use and Care of Animals. Multiple (range, 1-5) 2,4,6-trinitrobenzenesulfonic acid-ethanol enemas were used to create intestinal inflammatory lesions with variable fibrosis in female Lewis rats.

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Background And Aims: Intestinal fibrosis is a frequent complication in Crohn's disease [CD]. The mouse Salmonella typhimurium model, due to its simplicity, reproducibility, manipulability, and penetrance, is an established fibrosis model for drug discovery and preclinical trials. However, the severity of fibrosis and mortality are host- and bacterial strain-dependent, thus limiting the original model.

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Unlabelled: Acute pancreatitis has several underlying etiologies, and results in consequences ranging from mild to complex multi-organ failure. The wide range of pathology suggests a genetic predisposition for progression. We compared the susceptibility to acute pancreatitis in BALB/c and FVB/N mice, coupled with proteomic analysis, in order to identify potential protein associations with pancreatitis progression.

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The pathology of Crohn's disease (CD) is characterized by obstructing intestinal strictures because of inflammation (with high levels of hemoglobin), fibrosis (high levels of collagen), or a combination of both. The accurate characterization of the strictures is critical for the management of CD. This study examines the feasibility of characterizing intestinal strictures by Photoacoustic imaging (PAI) without extrapolation from superficial biopsies.

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Purpose: To compare the abilities of magnetization transfer magnetic resonance imaging (MT-MRI) and T2 -weighted signal intensity (T2 WSI) ratios to detect intestinal fibrosis in a Crohn's disease animal model.

Materials And Methods: Ten rats ("Group 1") received one trinitrobenzenesulfonic acid enema to induce acute colonic inflammation, while 10 additional animals ("Group 2") received multiple enemas to induce colonic inflammation and fibrosis. Gradient recalled-echo MT-MRI (5 and 10 kHz off-resonance) and T2 -weighted spin-echo imaging were performed 2 days after the last enema.

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Objectives: To determine whether bowel wall fibrosis can be detected in freshly resected human intestinal specimens based on ultrasound-derived shear wave speed.

Methods: Seventeen intact (>3-cm) bowel segments (15 small and 2 large intestine) from 12 patients with known or suspected inflammatory bowel disease were procured immediately after surgical resection. Ultrasound shear wave elastography of the bowel wall was performed by two methods (Virtual Touch Quantification [VTQ] and Virtual Touch-IQ [VT-IQ]; Siemens Medical Solutions USA, Inc, Mountain View, CA).

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Unlabelled: Formation of hepatocyte Mallory-Denk bodies (MDBs), which are aggregates of keratins 8 and 18 (K8/K18), ubiquitin, and the ubiquitin-binding protein, p62, has a genetic predisposition component in humans and mice. We tested the hypothesis that metabolomic profiling of MDB-susceptible C57BL and MDB-resistant C3H mouse strains can illuminate MDB-associated pathways. Using both targeted and unbiased metabolomic analyses, we demonstrated significant differences in intermediates of purine metabolism.

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Purpose: To determine if acoustic radiation force impulse elastography-derived bowel wall shear wave velocity (SWV) allows distinction of acutely inflamed from fibrotic intestine in a Crohn disease animal model.

Materials And Methods: University Committee on the Use and Care of Animals approval was obtained. An acute inflammation Crohn disease model was produced by treating eight Lewis rats with a single administration of trinitrobenzenesulfonic acid (TNBS) enema, with imaging performed 2 days later in the surviving six rats.

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Hepcidin is a liver-derived peptide hormone and the master regulator of systemic iron homeostasis. Decreased hepcidin expression is a common feature in alcoholic liver disease (ALD) and in mouse models of ethanol loading. Dysregulation of hepcidin signaling in ALD leads to liver iron deposition, which is a major contributing factor to liver injury.

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Unlabelled: Mallory-Denk bodies (MDBs) are hepatocyte inclusions commonly seen in steatohepatitis. They are induced in mice by feeding 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) for 12 weeks, which also causes porphyrin accumulation. Erythropoietic protoporphyria (EPP) is caused by mutations in ferrochelatase (fch), and a fraction of EPP patients develop liver disease that is phenocopied in Fech(m1Pas) mutant (fch/fch) mice, which have an inactivating fch mutation.

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Background: Intestinal fibrosis causes many complications of Crohn's disease (CD). Available biomarkers and imaging modalities lack sufficient accuracy to distinguish intestinal inflammation from fibrosis. Transcutaneous ultrasound elasticity imaging (UEI) is a promising, noninvasive approach for measuring tissue mechanical properties.

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Background: The natural history of Crohn's disease follows a path of progression from an inflammatory to a fibrostenosing disease, with most patients requiring surgical resection of fibrotic strictures. Potent antiinflammatory therapies reduce inflammation but do not appear to alter the natural history of intestinal fibrosis. The aim of this study was to determine the relationship between intestinal inflammation and fibrogenesis and the impact of a very early "top-down" interventional approach on fibrosis in vivo.

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Unlabelled: Fas ligand (FasL)-mediated hepatocyte apoptosis occurs in the context of acute liver injury that can be accompanied by intravascular coagulation (IC). We tested the hypothesis that analysis of selected protein fractions from livers undergoing apoptosis will shed light on mechanisms that are involved in liver injury that might be amenable to intervention. Proteomic analysis of the major insoluble liver proteins after FasL exposure for 4-5 hours identified fibrinogen-γ (FIB-γ) dimers and FIB-γ-containing high molecular mass complexes among the major insoluble proteins visible via Coomassie blue staining.

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Murine noroviruses (MNV) are currently the most prevalent viruses infecting mouse research colonies. Concurrent infection of research mice with these viruses can dramatically alter the experimental outcome in some research models, but not others. In this report, we investigated the effect of MNV1 and MNV4 on a murine model of intestinal inflammation and fibrosis induced by Salmonella typhimurium infection in C57BL/6 mice.

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A progressive decline in islet function is a major obstacle to success of islet transplantation. The cause of this decline is islet function is unclear, but immunosuppressive agents may contribute. Insulin-like growth factor-I (IGF-I) and betacellulin are important for islet cell survival and/or proliferation.

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For proper development and tissue homeostasis, cell cycle progression is controlled by multilayered mechanisms. Recent studies using knock-out mice have shown that animals can develop relatively normally with deficiency for each of the G1/S-regulatory proteins, D-type and E-type cyclins, cyclin-dependent kinase 4 (Cdk4), and Cdk2. Although Cdk4-null mice show no embryonic lethality, they exhibit specific endocrine phenotypes, i.

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The timing of cellular exit from the cell cycle during differentiation is specific for each cell type or lineage. Granulosa cells in the ovary establish quiescence within several hours after the ovulation-inducing luteinizing hormone surge, whereas they undergo differentiation into corpora lutea. The expression of Cdk inhibitors p21(Cip1/Waf1) and p27(Kip1) is up-regulated during this process, suggesting that these cell cycle inhibitors are involved in restricting proliferative capacity of differentiating granulosa cells.

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Most human tumors have mutations that result in deregulation of the cdk4/cyclin-Ink4-Rb pathway. Overexpression of D-type cyclins or cdk4 and inactivation of Ink4 inhibitors are common in human tumors. Conversely, lack of cyclin D1 expression results in significant reduction in mouse skin and mammary tumor development.

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The lactotroph undergoes dynamic regulation of cell cycle progression during pregnancy, as well as throughout the development of the pituitary. We recently reported that female mice with targeted disruption of Cdk4, one of the G(1)-regulatory cyclin-dependent kinases, are unable to support embryo implantation because of defective progesterone secretion from the corpus luteum. In this study, we demonstrate that this phenotype is not attributable to a primary defect in the corpus luteum but is a consequence of defective prolactin (PRL) production caused by inappropriate development of the pituitary lactotroph population.

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Cell cycle progression of granulosa cells is critical for ovarian function, especially follicular maturation. During follicular maturation, FSH induces cyclin D2, which promotes G1 progression by activating cyclin-dependent kinase-4 (Cdk4). Because cyclin D2-deficient mice exhibit a block in follicular growth, cyclin D2/Cdk4 has been hypothesized to be required for FSH-dependent proliferation of granulosa cells.

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