J Environ Sci Health A Tox Hazard Subst Environ Eng
October 2022
This study aimed to evaluate an alternative to reduce trihalomethane (THM) formation in brewing water. THM affects the organoleptic properties of water and, consequently, the produced beer. Water treatment based on common chemicals such as alum and free chlorine could potentially form THM.
View Article and Find Full Text PDFBackground: Takayasu's arteritis (TA) and inflammatory bowel disease (IBD) are chronic inflammatory granulomatous disorders that have rarely been concomitantly reported in case reports and small case series.
Objective: We report a series of seven cases of TA and IBD association in two referral centers with a comprehensive review of literature.
Methods: We analyzed retrospectively the electronic medical charts of TA-IBD patients at the University Hospital of São Paulo, Brazil, and at the Sheba Medical Center at Tel Aviv University, Israel.
Chemokines are essential for homeostasis and activation of the immune system. The chemokine ligand/receptor pairing CCL20/CCR6 is interesting because these molecules display characteristics of both homeostatic and activation functions. These dual characteristics suggest a role for CCR6 in the priming and effector phases of the immune response.
View Article and Find Full Text PDFEyewitness identification research has reliably shown that accurate identifications are faster than inaccurate identifications. Recently, D. Dunning and S.
View Article and Find Full Text PDFChemokines are a family of cytokines that exhibit selective chemoattractant properties for target leukocytes and play a significant role in leukocyte migration. In this study, we have investigated the role of the C-C chemokine, macrophage inflammatory protein (MIP)-3alpha/CC chemokine ligand 20, in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), a model of T cell-dependent inflammation. Expression in the CNS of MIP-3alpha, as determined by RT-PCR, increased in a time-dependent manner such that peak expression correlated with peak clinical disease.
View Article and Find Full Text PDFIn stimulated neutrophils, the majority of tyrosine-phosphorylated proteins are concentrated in Triton X-100 or NP-40 insoluble fractions. Most immunobiochemical studies, whose objective is to study the functional relevance of tyrosine phosphorylation are, however, performed using the supernatants of cells that are lysed in non-ionic detergent-containing buffers (RIPA lysis buffers). This observation prompted us to develop an alternative lysis protocol.
View Article and Find Full Text PDFThe regulation of nuclear protein transport by phosphorylation plays a central role in gene expression in eukaryotic cells. We previously showed that nuclear import of SV40 large tumor antigen (T-ag) fusion proteins is regulated by the CcN motif, comprising phosphorylation sites for casein kinase II and the cyclin-dependent kinase cdc2, together with the nuclear localization signal. Regulation of nuclear uptake by CcN motif kinase sites also holds true for the yeast transcription factor SWI5 and the Xenopus nuclear phosphoprotein nucleoplasmin.
View Article and Find Full Text PDFThe tyrosine phosphorylation responses initiated in human neutrophils by soluble and particulate agonists were characterized. Chemotactic factors, hematopoietic growth factors, and inflammatory microcrystals stimulated in a time- and concentration-dependent manner the tyrosine phosphorylation of distinct patterns of substrates: pp120, pp85, pp70, and pp60 in the case of chemotactic factors; pp155, pp130, pp120, pp85, pp60, and pp40 in the case of granulocyte macrophage-CSF; and pp130, pp120, pp70, and pp60 in the case of monosodium urate (MSU) crystals. Several of the single bands on one-dimensional blots (including pp40, pp70, and pp120) could be resolved into multiple spots on two-dimensional gels.
View Article and Find Full Text PDFBackground: Recent studies have indicated that the regulation of the activation of human neutrophils depends on tyrosine phosphorylation and on phospholipase D. Furthermore, a tentative causal relationship between these two signalling pathways has been indirectly implied derived through the use of inhibitors of tyrosine kinases. The fungal metabolite, wortmannin is at present the only compound known to inhibit the receptor-mediated activation of phospholipase D in human neutrophils.
View Article and Find Full Text PDFAlthough several tyrosine kinases are present in human neutrophils, little is known regarding the biochemical basis for their activation. We have identified two tyrosine kinase activities in 0.1 and 1% Triton cell extracts of human neutrophils using a non-denaturing gel assay.
View Article and Find Full Text PDFErbstatin, a recently described inhibitor of tyrosine kinases, has been used to examine the potential role of tyrosine phosphorylation in human neutrophil locomotion. Preincubation of human neutrophils with erbstatin inhibited both spontaneous and directed migration induced by chemotactic factors such as formylmethionylleucylphenylalanine (fMet-Leu-Phe) and leukotriene B4. The decreased migratory responses were correlated with an inhibition of adherence of neutrophils to serum-coated surfaces.
View Article and Find Full Text PDFThe effects of pertussis toxin (PT) on the growth and dimethylsulfoxide (Me2SO4)-induced differentiation of the HL-60 human promyelocytic leukemia cell line were tested. Cell growth was quantified by direct cell counts. Cell differentiation was estimated by measuring the expression of myeloid-specific cell-surface antigens (Mo-1 and fMet-Leu-Phe [fMLP] receptors), the ability of the cells to produce superoxide anions on stimulation with fMLP, the calcium ionophore A23187 and phorbol 12-myristate 13-acetate (PMA), and by monitoring the level of expression of messenger RNA (mRNA) for tumor necrosis factor alpha (TNF alpha).
View Article and Find Full Text PDFThe aim of the present study is to evaluate the involvement of human neutrophil tyrosine kinase(s) in the signal transduction mechanism of granulocyte-macrophage colony-stimulating factor (GM-CSF). Stimulation of neutrophils with GM-CSF resulted in a time- and dose-dependent phosphorylation of several proteins having estimated molecular weights of approximately 40, 55, 74, 97, 118, and 155 Kd, detected by immunoblot using a monoclonal antibody directed against phosphotyrosine. GM-CSF-induced tyrosine phosphorylation was inhibited in a dose- and time-dependent manner by the tyrosine kinase inhibitor erbstatin.
View Article and Find Full Text PDFThe role of tyrosine kinases in the responses of human neutrophils to chemotactic factors was examined using the recently described inhibitor erbstatin. Pre-incubation with erbstatin decreased the amount of tyrosine phosphorylation induced by the formylated oligopeptide formyl-methionyl-leucyl-phenylalanine (fMet-Leu-Phe) without effecting the binding of [3H]-fMet-Leu-Phe. Erbstatin also dose-dependently inhibited the production of superoxide anion induced by fMet-Leu-Phe and platelet-activating factor, but did not affect the oxidative burst induced by either the calcium ionophore A23187 or the phorbol ester phorbol 12-myristate 13-acetate.
View Article and Find Full Text PDF1. The mechanism by which incubation of human peripheral blood neutrophils with exogenous arachidonic acid leads to 5-lipoxygenase product synthesis was investigated. 2.
View Article and Find Full Text PDF1. The mechanism(s) involved in the mobilization of calcium induced by arachidonic acid in human neutrophils was investigated. 2.
View Article and Find Full Text PDFThe relationships between the chemotactic factor-stimulated mobilization of calcium, activation of the NADPH-oxidase, changes in cytosolic pH, and in the level of polymerized actin in human neutrophils have been examined. The approach taken was to use intracellular calcium chelators, and pharmacologic modulators (both positive and negative) of the NADPH-oxidase to measure the aforementioned responses under conditions where the calcium transients were abrogated and/or the generation of superoxide anions was either inhibited or augmented. The decrease in cytosolic pH induced by chemoattractants was inhibited by the calcium chelator BAPTA and by the diglyceride kinase inhibitor 6-[2-(4-[(4-fluorophenyl)phenylmethylene]-1-piperidinylethyl ]-7-methyl-5H-thiazolo[3,2-alpha]pyriimidin-5-one (R59022) (this latter compound enhanced the oxidative response of the cells).
View Article and Find Full Text PDFThe ability of propionic acid to elicit an increase in the level of cytoplasmic free calcium in human neutrophils was examined in detail. Propionic acid induced a rapid and dose-dependent mobilization of calcium that relied on both internal and external sources of calcium. The effects of propionic acid on the mobilization of calcium were inhibited by pertussis toxin, but not cholera toxin, implicating a guanine nucleotide binding protein.
View Article and Find Full Text PDFSeparate populations of serotonin- and adrenaline-containing neurons exist in the ventrolateral medulla oblongata and project to the intermediolateral cell column of the spinal cord. The medullary serotonin nuclei appear to constitute a heterogeneous group with diverse effects on arterial pressure. Microinjections of sodium glutamate (which excites cell bodies but not axons of passage) made in the area of the ventrolateral serotonin cells evokes an increase in arterial pressure which is abolished by prior 5,7-dihydroxytryptamine (5,7-DHT) treatment.
View Article and Find Full Text PDFElectrolytic lesions of the A1 noradrenaline cells in the caudal ventrolateral medulla cause transient hypertension and bradycardia in the conscious rat, as previously described in the rabbit. The lesions produced 100-fold increases in plasma arginine vasopressin, 40-fold increases in plasma adrenaline and fourfold increases in plasma noradrenaline levels. Absence of circulating vasopressin [homozygous diabetes insipidus rats (DI)] or circulating adrenaline (adrenalectomized rats) did not affect A1 hypertension, but sympathectomy with systemic 6-hydroxydopamine (6-OHDA) significantly attenuated A1 hypertension.
View Article and Find Full Text PDFAust N Z J Med
December 1980
Forty-eight women with urinary tract infection due to Co-trimoxazole sensitive organisms were randomly allocated to receive either two tablets (0.96 grams) of Co-trimoxazole twice a day for one day, four tablets (1.92 grams) of Co-trimoxazole as a single dose, or, two tablets of Co-trimoxazole twice a day for seven days.
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