Search results for "granulocytes"
showing 10 items of 63 documents
Genome-wide association studies identify 137 genetic loci for DNA methylation biomarkers of aging
2021
Abstract Background Biological aging estimators derived from DNA methylation data are heritable and correlate with morbidity and mortality. Consequently, identification of genetic and environmental contributors to the variation in these measures in populations has become a major goal in the field. Results Leveraging DNA methylation and SNP data from more than 40,000 individuals, we identify 137 genome-wide significant loci, of which 113 are novel, from genome-wide association study (GWAS) meta-analyses of four epigenetic clocks and epigenetic surrogate markers for granulocyte proportions and plasminogen activator inhibitor 1 levels, respectively. We find evidence for shared genetic loci ass…
Noninvasive assessment of Crohn's disease activity: a comparison of 18F-fluorodeoxyglucose positron emission tomography, hydromagnetic resonance imag…
2002
Detection of disease activity in Crohn's disease (CD) is of crucial importance for diagnosis and management of the disease. Noninvasive methods for monitoring are desirable and comprise hydromagnetic resonance imaging (hydro-MRI) and leukocyte scintigraphy. In addition, a recent case report indicated the potential of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) to assess CD activity. However, comparative prospective studies are lacking.Between February, 1999 and August, 2000, 59 patients with CD were enrolled in a prospective study to assess disease activity by FDG-PET, hydro-MRI, and immunoscintigraphy with anti-nonspecific cross-reacting antigen 95 antigranulocyte antibod…
In vivo effects of intravascularly applied Escherichia coli hemolysin: dissociation between induction of granulocytopenia and lethality in monkeys.
1993
The effects of intravascular application of endotoxin-depleted Escherichia coli hemolysin (HlyA) was studied in rabbits and monkeys. In rabbits, bolus application of HlyA calculated to effect final blood levels of approximately 2-3 HU/ml (200-300 ng/ml) caused an acute fall of polymorphonuclear blood leukocytes to less than 20% of starting levels within 5 min. Additionally, platelet counts dropped to approximately 30% of starting levels, whereas lymphocyte counts varied considerably and seldom fell to less than 50%. Nine out ten animals that received 2-4 HU/ml toxin died within 90 min post application. These animals presented with signs of acute respiratory failure and post mortem inspectio…
Crystal-phagocyte interaction in calcinosis interstitialis.
1984
Based on recent findings indicating the stimulation of the respiratory burst in human neutrophils by crystal phagocytosis, ectopic calcified nodules of a patient with calcinosis interstitialis were exposed to autologous granulocytes and monocytes in vitro. The activity of the respiratory burst was determined by luminol-enhanced chemiluminescence. Controls included amorphous monosodium urate, microcrystalline monosodium urate, hydroxyapatite, and zymosan. Microcrystalline monosodium urate elicited a marked stimulation of both granulocytes and monocytes as did hydroxyapatite in granulocytes. Hydroxyapatite caused no stimulation of monocytes, possibly reflecting selective functional modulation…
Granulocytes of sea anemone Actinia equina (Linnaeus, 1758) body fluid contain and release cytolysins forming plaques of lysis
2014
The Cnidaria phylum includes organisms that are among the most poisonous animals. The exact composition of cnidarian bioactive molecules is not known in detail, but little is known on the cells that produce the toxins. Here we have shown that the presence of cytolysins is not exclusive of nematocysts. A plaque-forming assay was carried out with cell populations extracted from the percoled body fluid showed for the first time that anthozoan granulocytes are able to form plaque of lysis. We have partitioned the total population of free cells into three distinct discrete bands by discontinuous Percoll gradient, and we have identified six small different types cells: morular granulocytes; cells…
Essential role of surface-bound chemoattractant in leukocyte migration
1977
MANY chemotactic factors, usually proteins or peptides, have been isolated and studied, but little is known about the basic mechanism of leukocyte migration. This movement is termed chemotaxis if its direction is determined by substances in the cells' environment1. The chemotactic agent is assumed to convey information to the leukocytes by interaction with receptors. The subsequent sequence of events thus triggered in the cells is unknown but metabolic changes such as activation of an esterase have been reported as occurring as the cells move forward (for review see ref. 2). A role for surface-bound chemoattractant in cell locomotion was suggested by the observation that mouse fibroblasts m…
The iNOS Activity During an Immune Response Controls the CNS Pathology in Experimental Autoimmune Encephalomyelitis
2019
Inducible nitric oxide synthase (iNOS) plays a critical role in the regulation of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). Previous studies have shown that iNOS plays pathogenic as well as regulatory roles in MS and EAE. However, how does iNOS alters the pathophysiology of the central nervous system (CNS) in neuronal autoimmunity is not clearly understood. In the present work, we show that treatment of mice with L-NAME, an iNOS inhibitor, during the antigen-priming phase primarily alters brain pathology, while in the subsequent effector phase of the immune response, the spinal cord is involved. Inhibition of iNOS during the priming phase of the immune res…
Binding of Escherichia coli hemolysin and activation of the target cells is not receptor-dependent.
2005
Abstract Production of a single cysteine substitution mutant, S177C, allowed Escherichia coli hemolysin (HlyA) to be radioactively labeled with tritiated N-ethylmaleimide without affecting biological activity. It thus became possible to study the binding characteristics of HlyA as well as of toxin mutants in which one or both acylation sites were deleted. All toxins bound to erythrocytes and granulocytes in a nonsaturable manner. Only wild-type toxin and the lytic monoacylated mutant stimulated production of superoxide anions in granulocytes. An oxidative burst coincided with elevation of intracellular Ca2+, which was likely because of passive influx of Ca2+ through the toxin pores. Competi…
Correlative histologic and arthroscopic evaluation in rheumatoid knee joints.
1992
The correlation between arthroscopic observations and histologic changes in rheumatoid arthritis is still controversial. Synovial samples of 21 knee joints in rheumatoid arthritis patients were comparatively investigated by endoscopy and histology. Biopsies were scored by an endoscopist and subsequently dissected. Different histochemical and immunocytochemical staining techniques were used to define inflammatory activity. Arthroscopic and histological values were compared by rating scales and variance analysis. Our study indicates that synovial biopsy is of diagnostic value in rheumatoid arthritis. However, its usefulness depends on the histochemical methods used. The results revealed highl…
Sustained telomere erosion due to increased stem cell turnover during triple autologous hematopoietic stem cell transplantation.
2007
Telomeres cap chromosomal ends and are shortened throughout a lifetime. Additional telomere erosion has been documented during conventional chemotherapy or hematopoietic stem cell transplantation. Previous studies of stem cell transplantation reported variable amounts of telomere shortening with inconsistent results regarding the persistence of telomere shortening. Here we have prospectively studied telomere length and proliferation kinetics of hematopoietic cells in aggressive non-Hodgkin lymphoma patients who underwent a four-course high-dose chemotherapy protocol combined with triple autologous stem cell transplantation. We observed sustained telomere shortening in hematopoietic cells af…