Enhancement of neutrophil autophagy by an IVIG preparation against multidrug-resistant bacteria as well as drug-sensitive strains.

Autophagy occurs in human neutrophils after the phagocytosis of multidrug-resistant bacteria and drug-sensitive strains, including Escherichia coli and Pseudomonas aeruginosa. The present study detected autophagy by immunoblot analysis of LC3B conversion, by confocal scanning microscopic examination of LC3B aggregate formation and by transmission electron microscopic examination of bacteria-containing autophagosomes. Patients with severe bacterial infections are often treated with IVIG alongside antimicrobial agents.

NB4 cells treated with all-trans retinoic acid generate toxic reactive oxygen species that cause endothelial hyperpermeability.

Retinoic acid syndrome (RAS) is a serious complication during induction therapy with all-trans retinoic acid (RA) in patients with acute promyelocytic leukemia. In this study, we examined whether reactive oxygen species (ROS) were involved in capillary leak phenomenon in RAS, using NB4 cells. When cells were stimulated by phorbol 12-myristate 13-acetate, RA-treated cells with matured myeloperoxidase produced toxic ROS, such as singlet oxygen, hypochlorous acid and hydroxyl radical, and brought about endothelial hyperpermeability.

[Human health sciences].

Medical science and medical practice developed remarkably and economic conditions progressed so much in recent years in Japan. As the result, the average span of life of the Japanese is now the longest in the world and we are well off. The matter of the greatest concern of Japanese people at present is health.

Alpha-phenyl-N-tert-butyl nitrone has scavenging activity against singlet oxygen ((1)O(2)) and attenuates (1)O(2)-induced neuronal cell death.

Scavenging activity of alpha-phenyl-N-tert-butyl nitrone (PBN) against singlet oxygen ((1)O(2)) and its effects on (1)O(2)-induced neuronal cell death were examined. PBN at 1 - 4 mM dose-dependently suppressed (1)O(2) released from activated human neutrophils. PBN did not react with hydrogen peroxide or hypochlorite and did not affect myeloperoxidase activity, which are involved in the (1)O(2) formation in neutrophils.

Ozone production by amino acids contributes to killing of bacteria.

Reactive oxygen species produced by phagocytosing neutrophils are essential for innate host defense against invading microbes. Previous observations revealed that antibody-catalyzed ozone formation by human neutrophils contributed to the killing of bacteria. In this study, we discovered that 4 amino acids themselves were able to catalyze the production of an oxidant with the chemical signature of ozone from singlet oxygen in the water-oxidation pathway, at comparable level to antibodies.

Familial Mediterranean fever gene as a possible modifier of Sweet syndrome with chronic myelogenous leukemia.

Sweet syndrome is a multisystem inflammatory disorder characterized by acute fever, as well as painful erythematous plaques infiltrated with mature neutrophils in the absence of vasculitis. The pathogenesis of the disease has not yet been clarified, although several proinflammatory cytokines have been reported to be involved in the disease process. We describe here a patient clinically diagnosed with Sweet syndrome with chronic myelogenous leukemia.

Effects of injectable propofol emulsion on singlet oxygen released from activated human neutrophils and that chemically generated.

Effects of an injectable emulsion of propofol and its emulsifier on singlet oxygen (1O2) were examined. 1O2 released from activated human neutrophils was detected by chemiluminescence, and chemically generated 1O2 was detected by electron paramagnetic resonance (EPR). Both the propofol emulsion and the emulsifier suppressed 1O2 release from neutrophils.

Anticancer photodynamic and non-photodynamic effects of pterin derivatives on a pancreatic cancer cell line.

To evaluate the feasibility of two kinds of pterin derivatives, 2-(N,N-dimethylaminomethyleneamino)-6-formyl-3-pivaloylpteridin-4-one (DFP) and 2-(N,N-dimethylaminomethyleneamino)-3-pivaloylpteridin-4-one (DP), as anticancer drugs, their photodynamic and non-photodynamic effects on pancreatic cancer cell line Panc-1 cells were examined. For photodynamic effects, cell death 48 h after UV-A irradiation was more prominent in cells preloaded with DP than DFP. When cells were simply incubated for 96 h without irradiation, DFP induced cell death, while DP suppressed cell proliferation.

The radical scavenger edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) reacts with a pterin derivative and produces a cytotoxic substance that induces intracellular reactive oxygen species generation and cell death.

Cytotoxic effects of the combined use of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a radical scavenger and an approved medicine for acute brain infarction in Japan, with a pterin derivative, were examined in vitro. When pancreatic cancer cell line Panc-1 cells were incubated with 50 to 400 microM of a pterin derivative, 2-(N,N-dimethylaminomethyleneamino)-6-formyl-3-pivaloylpteridine-4-one (DFP), and the equivalent dose of edaravone, reactive oxygen species (ROS), were generated, and cell death was induced. ROS generation and the loss of mitochondrial membrane potential (MMP) preceding cell death were simultaneously monitored using time-lapse microscopy with an ROS-sensitive dye and a probe to monitor MMP, respectively.

Inhibitory effect of 6-formylpterin on HIF-1alpha protein accumulation.

Hypoxia-inducible factor-1 (HIF-1) is a main regulator of metabolic adaptation to hypoxia. HIF-1alpha is induced by hypoxia, or by hypoxia-mimicking reagents, such as desferrioxamine (DFX), under a normoxic condition. A xanthine oxidase inhibitor, 6-formylpterin (6FP), is reported to exert its functions on reactive oxygen species (ROS) modulation.

Analysis of serum angiogenic factors in a young multiple myeloma patient with high-output cardiac failure.

Angiogenesis is believed to be involved in the pathogenesis and progression of multiple myeloma (MM). In some young patients, the MM has been reported to be complicated with high-output cardiac failure (HOCF), in which an increase in the vascular bed may be involved in the pathogenesis; however, no throughput studies have been conducted to determine what angiogenic factors are associated with HOCF in MM patients. We experienced a 34-year-old MM patient with HOCF and used the cytokine array system to investigate the expression of angiogenic cytokines and related factors in his serum before and after treatment and to compare the results with those of a healthy volunteer.

Effects of edaravone on singlet oxygen released from activated human neutrophils.

The effects of edaravone, a curative agent for acute brain infarction, on singlet oxygen ((1)O2) released from activated human neutrophils were examined, and the effects were compared to those of histidine, a (1)O2 singlet oxygen scavenger. The neutrophils, stimulated with opsonized zymosan, released (1)O2 that was detected by chemiluminescence using a (1)O2 specific probe, trans-1-(2'-methoxyvinyl)pyrene. Edaravone dose-dependently suppressed the (1)O2 release with an IC(50) of approximately 0.

LPS-induced ROS generation and changes in glutathione level and their relation to the maturation of human monocyte-derived dendritic cells.

Lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) generation and the concomitant decline in the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) were demonstrated in human monocyte-derived dendritic cells (DC). Further, their relation to the maturation of DC, characterized by the production of cytokines, up-regulation of cell surface molecules and allo-stimulatory capacity, was examined. The LPS-induced ROS generation was demonstrated using electron paramagnetic resonance spectroscopy in intact cells, and was also confirmed using laser scanning confocal microscopy.

Photodynamic effects of a novel pterin derivative on a pancreatic cancer cell line.

6-Formylpterin (6FP) has the potential to produce singlet oxygen (1O2) under UV-A radiation. In order to apply this potential to anti-cancer photodynamic therapy (PDT), we prepared a novel variant of 6FP, 2-(N,N-dimethylaminomethyleneamino)-6-formyl-3-pivaloylpteridine-4-one (6FP-tBu-DMF), and examined its photodynamic effects on a pancreatic cancer cell line, Panc-1 cells. The study using laser scanning confocal microscopy showed that the drug uptake, the 1O2 generation, and cell death were observed in the 6FP-tBu-DMF-treated cells, while these phenomena were not observed in the 6FP-treated cells.

Nitric oxide derived from human umbilical vein endothelial cells inhibits transendothelial migration of neutrophils.

We evaluated the roles of nitric oxide (NO) derived from endothelial cells in neutrophil transendothelial migration (TEM). Pretreatment of human umbilical vein endothelial cells (HUVECs) with NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) or NG-monomethyl L-arginine (L-NMMA), which are inhibitors of NO synthases, enhanced neutrophil TEM. Similar augmentation of TEM was observed in the presence of an NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy PTIO).

Short-term delay of Fas-stimulated apoptosis by GM-CSF as a result of temporary suppression of FADD recruitment in neutrophils: evidence implicating phosphatidylinositol 3-kinase and MEK1-ERK1/2 pathways downstream of classical protein kinase C.

Granulocyte/macrophage colony-stimulating factor (GM-CSF) inhibits Fas-induced apoptosis of neutrophils. However, the exact step in the apoptotic pathway blocked by GM-CSF remained unclear. Here, we found that pretreatment of neutrophils with GM-CSF inhibits the recruitment of Fas-associated protein with death domain (FADD) to Fas, abolishing the formation of the death-inducing signaling complex required for Fas-induced apoptosis.

E148Q/M694I mutation in 3 Japanese patients with familial Mediterranean fever.

We describe 3 unrelated Japanese patients with familial Mediterranean fever (FMF) due to a compound heterozygous E148Q/M694I mutation in the MEFV gene. The first patient is a 38-year-old man who also has chronic myelogenous leukemia (CML). Because genomic DNA analysis of the patient's nail revealed the E148Q/M694I mutation, we concluded that the individual mutations were obtained congenitally.

Effects of intracellular reactive oxygen species generated by 6-formylpterin on T cell functions.

The intracellular generation of reactive oxygen species (ROS) by 6-formylpterin and its effects on the human T cell functions were examined in vitro. When T cells isolated from fresh blood were incubated with 6-formylpterin for 1hr, the oxygen consumption and concomitant ROS generation were observed. The incubation of T cells with 50-500microM 6-formylpterin for 24hr brought about the elevation of intracellular ROS without inducing cell death.

Effects of 6-formylpterin as an internal source of hydrogen peroxide on cell death of human peripheral blood leukocytes.

The intracellular generation of hydrogen peroxide (H(2)O(2)) by 6-formylpterin and its effects on the cell surface exposure of phosphatidylserine (PS) as a marker of cell death were examined in human peripheral blood leukocytes, and the effects were compared with those of exogenously administered H(2)O(2). Neutrophils, monocytes and lymphocytes were isolated from fresh blood, and cultured for 24 h in vitro. In neutrophils, the intracellular H(2)O(2) generation was observed when the cells were incubated with 100-500 microM 6-formylpterin, and the PS exposure due to spontaneous apoptosis was inhibited.

The serum cytokine profiles of lymphoma-associated hemophagocytic syndrome: a comparative analysis of B-cell and T-cell/natural killer cell lymphomas.

To elucidate the differences in pathogenesis between lymphoma-associated hemophagocytic syndromes (LAHS) of the T-cell/ natural killer cell (T/NK) and B-cell (B) types, we comparatively analyzed the clinical features and serum cytokine profiles of 33 patients with LAHS registered in the Kyoto University Hematology/Oncology Study Group. The serum cytokine levels of each patient group (B-LAHS versus T/NK-LAHS) were expressed as the ratio of the median to the upper normal values of the respective cytokines and were as follows: 19.05 versus 13.