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P J Spagnuolo

Publications and source records attributed to P J Spagnuolo.

At least 19 recordsLinked to original sources
PubMed1997

Leukotriene C4 from vascular endothelium enhances neutrophil adhesiveness.

We have examined the synthesis of leukotriene C4 from bovine aortic and pulmonary artery endothelium. Under basal conditions, neither aortic nor pulmonary artery endothelium revealed significant amounts of hydroxy fatty acids. Following incubation with ionophore A23187, several peaks including one which co-migrated with authentic LTC4 could be demonstrated from both aortic and pulmonary endothelium. LTC4 production was maximal after 30 min incubation, was inhibitable by the lipoxygenase inhibitor nordihydroguairetic acid, and was synthesized by bovine endothelium from tritiated arachidonic acid substrate. The putative LTC4 from endothelium was shown to be identical to authentic LTC4 by chromatography and scanning UV spectroscopy. Endothelial-derived LTC4 increased the adherence of bovine aortic endothelium for neutrophils in a concentration dependent pattern similar to authentic LTC4. These data suggest that vascular endothelium may influence leukocyte-endothelial interactions through synthesis of biologically active arachidonic acid metabolites such as LTC4.

Animals↗
PubMed1997

Tumor cell-endothelial cell interactions: evidence for roles for lipoxygenase products of arachidonic acid in metastasis.

Adhesion of tumor cells (TC) to endothelial cells (EC) is necessary for movement of TC out of the interstitium to form metastatic deposits. This interaction may be influenced by proadhesive molecules such as lipoxygenase products of arachidonic acid metabolism. We studied the effect of inflammatory stimuli, A23187 calcium ionophore, n-formyl-methionyl-leucine-phenylalanine (FMLP) and phorbol myristate acetate (PMA) on TC-EC interaction. Adherence of metastatic breast tumor cell line (MCF-7), choriocarcinoma cell line (JEG-3), and non metastatic pituitary cell (GH-3) were assayed as the number of radiolabeled TC attached to EC (cpm/well). TC and EC were incubated with A23187, FMLP, and PMA for varying time periods. Lipoxygenase products (LTB4, 5-HETE) were measured under basal and stimulated conditions using RP-HPLC and RIA. There were no differences in basal adherence of TC lines to EC. When EC were incubated with stimuli, there were significant increases in the numbers of MCF-7 and JEG-3 cells adherent to EC compared to GH-3. Light and phase contrast microscopy confirmed that TC were attached to EC. Upon stimulation, GH-3 preferentially produced prostaglandins (PGI1(2)) while MCF-7 and JEG-3 produced lipoxygenase products (LTB4 and 5-HETE). Pre-incubation of MCF-7 and JEG-3 with the lipoxygenase inhibitor nordihydroguiaretic acid resulted in partial inhibition of adhesion to EC. Our data strongly indicate a role for lipoxygenase products of arachidonic acid in adherence of TC to EC.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1993

Human neutrophil adhesion to bovine aortic endothelium. Evidence for endothelial lipoxygenase activity.

We examined the effect of phorbol myristate acetate on cultured bovine aortic endothelial cells to determine the role of endothelial cells in neutrophil-endothelial cell adhesive interactions. Confluent endothelial cells were preincubated with phorbol myristate acetate and other inflammatory signals including N-formylmethionyl-leucyl-phenylalanine (f-Met-Leu-Phe), the ionophore A23187, and thrombin; washed extensively; and incubated with 51Cr-labeled neutrophils. Preincubation of endothelium with A23187, phorbol ester, or thrombin increased adherence of neutrophils by 3.1-, 5.7-, and 3.7-fold over baseline. In contrast, f-Met-Leu-Phe preincubation failed to increase adhesion over baseline. Supernatants from endothelium preincubated with phorbol failed to augment adherence of untreated endothelial cells. Preincubation of endothelium with lipoxygenase inhibitors nordihydroguaiaretic acid (50 microM), 5,8,11,14-eicosatetraenoic acid (50 microM), and BW755C (50 microM) inhibited the effect of phorbol preincubation of endothelium significantly by 55, 27, and 22%, respectively. In contrast, inhibitors of cyclooxygenase and thromboxane synthase or thromboxane receptor antagonists had no effect on phorbol-induced adhesion. Specific desensitization of neutrophil adhesion to phorbol-treated endothelium could be demonstrated by prior exposure of neutrophils to low concentrations of leukotriene B4 (3.8 x 10(-10) M). Endothelium preincubated with phorbol but not f-Met-Leu-Phe or thrombin produced several fatty acid peaks at 280 nm, one of which comigrated with authentic leukotriene B4 (LTB4). This peak, isolated and purified, increased endothelial cell adherence in a temporal fashion in the same way as LTB4 and was demonstrated to be LTB4 by ultraviolet spectroscopy, high-performance liquid chromatography, and mass spectroscopy. These data demonstrate that endothelial cell-derived lipoxygenase metabolites, in particular LTB4, are involved, in part, in the acute regulation of neutrophil adhesion to endothelium induced by inflammatory signals such as phorbol ester.

Animals↗
PubMed1993

Neutrophil lipoxygenase metabolism and adhesive function following acute thermal injury.

Leukotrienes, especially leukotriene B4, are important modulators of various neutrophil functions including adherence and chemotaxis. In previous work, we demonstrated that neutrophil adherence to extracellular matrixes was diminished in the acute stages of burn injury. In this study, we demonstrated that neutrophil adhesion to human and bovine endothelium in the baseline state and after stimulation with leukotriene B4 is depressed markedly after burn injury. The defect in stimulated adherence to endothelium was not specific to leukotriene B4 because impaired adhesion was observed with n-formyl-methionyl-leucyl-phenylalanine and ionophore A23187 as well. Moreover, the adherence defect correlated with 95% and 81% decreases in the release of leukotriene B4 and 5-hydroxy-(6E,87,117,147)-eicosatetraenoic acid, respectively, from burn PMN treated with A23187. Burn neutrophils also released proportionately more byproducts of leukotriene B4 omega oxidation, particularly 20-COOH-leukotriene B4, than did control neutrophils. When examined 3 1/2 weeks after injury, abnormalities in neutrophil leukotriene B4 generation and the adherence of burn neutrophils had recovered to near normal values. To determine whether the decreased release of leukotriene B4 from burn neutrophils was due to increased degradation or diminished synthesis of leukotriene B4, we examined the degradation of exogenous tritiated leukotriene B4 as well as the production of leukotriene B4 from tritiated arachidonic acid in neutrophils. Burn neutrophils converted significantly greater quantities of tritiated leukotriene B4 to tritiated 20-COOH-leukotriene B4 and synthesized markedly less tritiated leukotriene B4 from tritiated arachidonic acid than did control neutrophils, suggesting that decreased leukotriene B4 release by burn neutrophils was the result of both enhanced degradation and decreased synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Platelet activating factor amplifies human neutrophil adherence to bovine endothelial cells: evidence for a lipoxygenase dependent mechanism.

Platelet activating factor (PAF) is a potent lipid mediator that induces the release of leukotrienes and prostaglandins from various cells and tissues. We examined the capacity of PAF alone and in combination with soluble stimuli to enhance eicosanoid synthesis and adherence of human neutrophils. Neutrophils were preincubated with PAF and washed before exposure to the soluble stimuli F-Met-Leu-Phe (FMLP), calcium ionophore A23187, and phorbol myristate acetate. Preincubation of neutrophils with 1 microM PAF enhanced the release of both LTB4 and LTC4 in response to each of the three agonists, in contrast with the unprimed neutrophils. Priming was specific for PAF since lyso-PAF was inactive. Priming concentrations of PAF also augmented the adherence of neutrophils to endothelium in the presence of the soluble agonists A23187, phorbol myristate acetate, and FMLP. The priming effect of PAF on eicosanoid release and neutrophil adherence was shown to have similar time- and dose-dependent effects. Further, the priming effects of PAF on adherence could be reversed by preincubation of neutrophils with the lipoxygenase inhibitors nordihydroguiaretic acid and 5,8,11,14-ETYA but not by preincubation with the cyclooxygenase inhibitor indomethacin. These data demonstrate that PAF amplifies neutrophil adherence to endothelium through a lipoxygenase dependent mechanism.

Amino Acid Sequence↗
PubMed1992

Fibronectin binding and neutrophil aggregation in burn injury.

Fibronectin (Fn) plays an important role in the adhesive function of many cells including neutrophils (PMN). We examined the hypothesis that activated PMN develop binding sites for fibronectin which allows for the aggregation of contiguous PMN. Because PMN adhesive function is altered in acute burn injury, we also investigated the role of Fn in the aggregation of PMN from subjects with acute thermal injury. The chemotactic peptide, n-formylmethionyl leucyl phenylalanine, induced rapid binding of radioiodinated plasma Fn to PMN. Significant binding of Fn was detected as early as 30 sec poststimulus and maximal binding occurred at 5 min. Fn binding was only partially reversible and nonsaturable. The chemotactic peptide induced aggregation and binding of Fn to PMN with similar kinetics, concentration dependence, temperature, and cation requirements. In burn patients, PMN demonstrated a significant decrease in chemotactic peptide-induced aggregation which was associated with decreased binding of Fn. Alterations in the binding of Fn to PMN may be responsible, in part, for diminished aggregation responses of PMN in the early stages of thermal injury.

Burns↗
PubMed1992

Cutaneous manifestations of toxoplasmosis.

Toxoplasmosis is a common, largely asymptomatic infection. Early reports of acquired disease noted frequent dermatologic manifestations, whereas recent reviews of toxoplasmosis stress the lymphadenopathic presentation of the disease. We report the case of a patient with acute toxoplasmosis associated with a prominent macular and papular rash involving the palms and soles. We have reviewed the literature on dermatologic manifestations of acute acquired toxoplasmosis to underscore the importance of considering toxoplasmosis in the differential diagnosis of febrile illnesses with varied dermatologic presentations.

Acute Disease↗
PubMed1991

Protease priming of neutrophil superoxide production. Effects on membrane lipid order and lateral mobility.

Phagocyte superoxide (O2-) response is primed by a variety of physiologic compounds including the neutrophil secretory proteases cathepsin G and elastase. To study whether protease priming of neutrophil O2- response is related to changes in membrane physical state, we examined enzyme effects on the order and lateral mobility of lipid probes in intact neutrophil membranes. Exposure to cathepsin G (5 micrograms/ml) or elastase (10 micrograms/ml) caused a significant decrease in fluorescence anisotropy of the probe trimethylammonium diphenylhexatriene in neutrophil plasma membranes (0.279 to 0.256 for cathepsin G, 0.274 to 0.256 for elastase, p less than 0.02 for both), indicating a decrease in phospholipid chain order in the surface membrane bilayer. Cathepsin G and elastase also caused significant increases in membrane lipid lateral mobility as measured by excimer formation of the fluorescent probe 1-pyrenedecanoic acid (for cathepsin G, a 107% increase, and for elastase, a 44% increase in excimer/monomer fluorescence ratio, p less than 0.001). Enzyme effects on membrane structure were dependent on intact proteolytic activity, and were cell specific; the proteases had no effect on lipid order or lateral mobility in liposomes. In corollary studies, the possible association between the physical state of the polymorphonuclear leukocyte membrane and O2- generation was analyzed with the membrane modifying compounds, linoleic acid, ethanol, and cholesterol. Cell exposure to linoleic acid (1 microM) caused a significant decrease in lipid order and an increase in lipid lateral mobility along with increased O2- production to N-formyl-Met-Leu-Phe (fMLP) (191%) and phorbol myristate acetate (PMA) (39%), p less than 0.02 for each. 3 mM ethanol also augmented O2- response to fMLP (31%) and PMA (48%) and caused a significant decrease in lipid order, but did not affect lipid lateral mobility. Treatment with cholesteryl hemisuccinate (100 micrograms/ml) resulted in increased lipid order and decreased lipid lateral mobility, as well as decreased neutrophil superoxide response to fMLP (-61%, p less than 0.001) and PMA (-50%, p less than 0.02). We then examined whether modulation of membrane physical state may explain the mechanism of action of a known priming agent by studying the effects of low concentrations of a diacylglycerol. Cells treated with 10 microM 1-oleoyl-2-acetyl-sn-glycerol had a greater than 8-fold increase in superoxide response to fMLP (p less than 0.001) while demonstrating a significant decrease in lipid order (0.289 to 0.281, p less than 0.01) and a 50% increase in lipid lateral mobility (p less than 0.001).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Binding of C-reactive protein to human neutrophils. Inhibition of respiratory burst activity.

We investigated the binding of highly purified soluble human C-reactive protein (CRP) to human neutrophils. Binding of CRP to neutrophils was rapid (50% of maximal binding occurred within 15 seconds), and complete within 5 minutes. Binding was inhibitable by excess unlabeled CRP, and nonspecific binding in the presence of a 200-fold excess of unlabeled CRP was 10% of total binding. Binding was not affected by other proteins, including albumin, fibronectin, rabbit IgG, or normal human plasma. Maximal binding required both calcium (0.5 mM) and magnesium (0.24 mM) ions. Calcium phosphorylcholine (10 micrograms/ml) or sodium citrate (10 micrograms/ml) completely dissociated bound CRP. Binding was saturable and most consistent with a 2-site model, demonstrating both a high-affinity receptor (1.4 x 10(4) sites/cell; Kd 3.7 x 10(-10) M) and a low-affinity receptor (4.2 x 10(5) sites/cell; Kd 2.5 x 10(-8) M). CRP at concentrations of 50 micrograms/ml inhibited the neutrophil superoxide production induced by phorbol ester. At concentrations of 100 micrograms/ml or greater, CRP also inhibited superoxide production in a cell-free xanthine oxidase-acetaldehyde system. These data suggest that CRP can down-regulate neutrophil oxidative capacity through interaction with receptors on neutrophils as well as by direct antioxidant activity.

C-Reactive Protein↗
PubMed1990

Neutrophil adhesion in the elderly: inhibitory effects of plasma from elderly patients.

Neutrophil (PMN) adherence is a critical component of host defense against infection. We questioned whether abnormalities of PMN adherence may be responsible, in part, for the increased susceptibility to infection in the elderly. We examined the adherence of 51Cr-labeled PMN from 18 elderly (65-95 years) and 18 younger subjects (18-40 years) to gelatin-coated plastic (gel) and bovine aortic endothelial monolayers (BAEC). There was no difference in unstimulated or baseline adherence of elderly or control PMN to either gel or BAEC substrates. N-Formyl-methionyleucylphenylalanine (FMLP), phorbol myristate acetate (PMA), and calcium ionophore A23187 (CI) significantly increased adherence of elderly PMN to gel and BAEC by 204 and 140% for FMLP, 271 and 263% for PMA, and 211 and 150% for CI, respectively. No differences were observed in the increment in stimulated adherence between young and elderly PMN. In contrast, in 5 of 18 subjects, incubation of elderly or young PMN with 10% elderly plasma resulted in greater than 25% inhibition in baseline adherence to BAEC compared to their sex-matched controls. The effect of elderly plasma was specific for BAEC and not seen with the gel substrate and was also demonstrated using human venous endothelium. When the adherence assay was repeated with varying ratios of elderly and young plasma, PMN adherence to BAEC correlated inversely with the proportion of elderly plasma in the assay. With greater than 70% elderly plasma, adherence was depressed below that observed in the absence of plasma. These data suggest the presence of a factor(s) in elderly plasma which may diminish adherence to endothelium. This factor(s) may be important in the increased risk of infection in a segment of the elderly population.

Aging↗
PubMed1990

Anterior segment upper lobe tuberculosis in the adult. Occurrence in primary and reactivation disease.

Nine patients with pulmonary tuberculosis involving predominantly or exclusively the anterior segment of one or both upper lobes were seen over a five-year period. The incidence of anterior segment upper lobe tuberculosis was 6.3 percent of 142 patients presenting with pulmonary tuberculosis during the same time period. Five of the nine patients with anterior segment upper lobe involvement had reactivation disease. An increased incidence of advanced age, diabetes, associated malignant neoplasms, alcoholism, and steroid use were noted in those patients with anterior segment involvement, although only the occurrence of diabetes was statistically significant. We suggest vigilance with regard to the diagnosis of tuberculosis in patients who are elderly, diabetic, or alcohol abusers, particularly where the roentgenographic appearance of anterior segment upper lobe involvement would tend to favor an alternative diagnosis.

Adult↗
PubMed1989

Emergence of a new opportunistic pathogen, Candida lusitaniae.

Candida lusitaniae has been an infrequently reported opportunistic pathogen. Most previously reported cases of serious infection caused by this organism have proven fatal and were associated with amphotericin resistance of the organism. We report two patients with hematologic malignancies undergoing cytotoxic chemotherapy who developed fungemia with this organism while they were granulocytopenic. The organisms isolated from each patient were fully susceptible and were treated successfully with amphotericin B. When isolated from an immunocompromised host, C. lusitaniae should be considered an opportunistic pathogen and undergo antifungal susceptibility testing. Amphotericin B should be considered the drug of choice, but a poor clinical response may be indicative of a resistant isolate.

Adult↗
PubMed1988

Mediation of augmented monocyte adhesiveness by thromboxane.

We examined the potential contribution of thromboxanes in human monocyte adherence to plastic. Monocyte adherence to plastic could be augmented by various stimuli including lipopolysaccharide, chemotactic peptide, and supernates of antigen-stimulated lymphocytes. Increments in monocyte adhesiveness were suppressed by inhibition of cyclooxygenase, thromboxane synthetase, or by antiserum to thromboxane B2. Neither prostaglandin E2 or F2 alpha significantly affected baseline or lipopolysaccharide-stimulated monocyte adherence. Additional experiments confirmed incremental production of thromboxane B2 by monocytes after incubation with lipopolysaccharide. Thromboxane B2 itself did not stimulate monocyte adhesiveness. These data demonstrate that monocytes release thromboxane A2 following stimulation and suggest that thromboxane A2 may play a significant role in monocyte-substrate attachment.

Carbazoles↗
PubMed1988

Neutrophil adhesive dysfunction in thermal injury: the role of fibronectin.

We examined neutrophil substrate adherence in 19 subjects with burns involving 1%-83% of their body surface area. Within 24 h of injury, neutrophils from burn patients demonstrated a 50% reduction in adhesion to both gelatin and plastic substrates when stimulated with N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP), phorbol myristate acetate, and calcium ionophore A23187. Neutrophil substrate adherence examined as long as two weeks after burn injury remained abnormal. Neutrophils, from burn patients, stimulated with FMLP, phorbol myristate acetate, and calcium ionophore A23187 demonstrated a 51%, 37%, and 45% decrease, respectively, in release of immunoreactive fibronectin compared with control neutrophils. In neutrophils from burn patients there was a 31% reduction in total neutrophil-associated fibronectin compared with controls. The decrement in release and total cellular content of fibronectin in neutrophils from burn patients did not change when reexamined on day 7 after injury. The magnitude and time course of alterations in the cellular content and release of fibronectin correlate with adhesive dysfunction after burn injury.

Adult↗
PubMed1988

'Punch' actinomycosis causing osteomyelitis of the hand.

Osseous actinomycosis usually results from direct invasion of bone from adjacent soft-tissue infection. Involvement of the jaw and vertebral column has been frequently reported, but involvement of the bones of the wrist or hand is rare. A patient with osteomyelitis of the distal right first metacarpal bone due to Actinomyces israelii following a punch injury during fisticuffs is described. Review of similar cases revealed a striking association of this type of infection with punch injuries; hence the term, punch actinomycosis. Analysis of the pus in these infections typically reveals sulfur granules; strict anaerobic conditions must be employed to culture the etiologic agent, A israelii. Management of individual cases should include surgical débridement combined with high-dose parenteral penicillin, followed by long-term penicillin therapy, orally.

Actinomycosis↗
PubMed1988

Neutrophil adhesive dysfunction in diabetes mellitus; the role of cellular and plasma factors.

We examined neutrophil adherence to bovine aortic endothelial cells in 26 patients with diabetes compared with age- and sex-matched controls. The adherence of chromium 51-labeled neutrophils from patients with diabetes in the basal state and after incubation with phorbol myristate acetate (PMA) but not N-formyl-methionyl-leucyl-phenylalanine (FMLP) was decreased significantly. A subset of 16 of 26 patients demonstrated highly significant decreases in basal adhesion. No significant correlation was found between defective adherence and metabolic control as assessed by plasma glucose level (range 44 to 508 mg/dl) and hemoglobin A1 level (range 7.7% to 17.1%) at the time of study. Plasma from patients with diabetes increased adherence of both diabetic and control neutrophils in the basal state. The adherence-augmenting factor in diabetic plasma was found to be nonfilterable and partially heat labile and to manifest the characteristics of a protein. The adhesive effects of diabetic plasma were mediated through alterations in endothelium rather than neutrophils. Diabetic neutrophil aggregation induced by PMA, FMLP, and calcium ionophore was normal in all patients examined, regardless of the aggregating agent used. Fibronectin release in the basal state and after stimulation with FMLP was found to be comparable in diabetic and control neutrophils. These studies demonstrated intrinsic adhesive dysfunction of diabetic neutrophils and a factor or factors in diabetic plasma that enhanced adherence to endothelium. These cellular and humoral factors may act together to prevent tissue emigration of neutrophils and may contribute to the pathogenesis and susceptibility of infection in diabetes.

Adult↗
PubMed1987

Fibronectin is stored but not synthesized in mature human peripheral blood granulocytes.

To investigate whether peripheral blood granulocytes can synthesize the adhesive glycoprotein, fibronectin, we sought to demonstrate the presence of messenger RNA coding for fibronectin within mature circulating granulocytes. Polyadenylated-enriched RNA was isolated from human peripheral blood granulocytes, human skin fibroblasts (synthesize fibronectin) and HeLa cells (lack fibronectin) and probed with a cDNA clone coding for the cell attachment domain of fibronectin. Hybridization of a fibronectin cDNA fragment occurred with fibroblast RNA but did not occur with granulocyte RNA despite a 100 fold excess granulocyte RNA. Incubation of granulocytes with n-formyl methionyl leucyl phenylalanine, a chemotactic peptide known to augment the release of fibronectin from granulocytes, failed to induce detectable levels of mRNA for fibronectin in granulocytes. There was no difference in the quantity of fibronectin released from chemotactic peptide-stimulated granulocytes pre-incubated in the presence or absence of the protein synthesis inhibitor, cycloheximide, suggesting that fibronectin exists in a stored form in granulocytes. These data suggest that fibronectin in mature granulocytes is the product of synthesis during early myeloid maturation.

Cells, Cultured↗