Cellular proliferation in the cerebral cortex following neural excitation in rats

Cortical spreading depression (SD) is characterized by propagation of neuronal/glial membrane depolarization throughout the unilateral cerebral cortex and has been linked to several neurological disorders, including migraine aura and epilepsy. SD induction resulted in a dramatic increase in BrdU-incorporated cells in the ipsilateral cortical hemisphere that was dependent on the number of elicited SD. Immunohistochemical studies revealed that 53% of the BrdU-labeled cells in the SD-generated cortex were NG2 immunopositive and 25% were OX-42 immunopositive. The remaining 22% of BrdU-incorporated cells showed no immunoreactivity to GST-rr, GFAP, NeuN, NG2 or OX-42.These data indicate that functional excitation of the cerebral cortex induces proliferative response in cortical cells, which may subsequently differentiate into glial progenitor or microglia within 3 days after stimulation.     

Anionic copolymerization of β-lactones in correlation with the mode of fission. studies on the syntheses of aliphatic polyesters. XI

The copolymerization behavior of β-propiolactone (PL) and α.α-bischloromethyl β-propiolactone (α-BCPL) is correlated with the mode of fission. With sodium acetate as catalyst, the formation of β-acetoxy propionic acid at the initiation reaction was observed and α-BCPL was more than five times as reactive as PL in copolymerization. Thus propagation by carboxylate anion through alkyl-oxygen fission was presumed in the case of pyridine and the acetate of Na, Li, and Mg as catalyst. On the other hand, the formation of ethyl β-hydroxy propionate and the decreased reactivity of α-BCPL in copolymerization was observed with magnesium and aluminum ethoxide as catalyst. In the case of the ethoxide of Na, Li, and Al, and Et₂Mg or Et₃Al as catalyst, propagation by alkoxide anions through acyl-oxygen fission of the coordinated lactones was presumed.     

Effects of granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor on respiratory burst activity of neutrophils in patients with myelodysplastic syndromes.

The superoxide (O2-)-releasing capacity in response to N-formyl-methionyl-leucyl-phenylalanine (FMLP) and the priming effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on FMLP-induced O2- release were investigated in neutrophils from 14 patients with myelodysplastic syndromes (MDS). The O2(-)-releasing capacity in MDS neutrophils varied from patient to patient. As compared with normal neutrophils, the O2(-)-releasing capacity in MDS neutrophils was increased in 9/14 patients, normal in three patients and decreased in two patients. There was no close relationship between the O2(-)-releasing capacity and the peripheral blood neutrophil count or the plasma concentration of C-reactive protein. The priming of neutrophils by rhG-CSF was not observed in five patients, whereas rhGM-CSF primed neutrophils from all patients. The priming effect of rhGM-CSF was consistently greater than that of rhG-CSF in each patient. The intravenous administration of rhG-CSF (300 micrograms/body) to two MDS patients showed an increase in the peripheral blood neutrophil count and enhancement of neutrophil O2- release. These findings demonstrate that the neutrophil O2(-)-releasing capacity in MDS varies from patient to patient and is not always impaired, and that rhGM-CSF is able to prime neutrophils which never respond to rhG-CSF.     

An anxiolytic agent, dihydrohonokiol-B, inhibits ammonia-induced increases in the intracellular Cl(-) of cultured rat hippocampal neurons via GABA(c) receptors

The effects of an anxiolytic honokiol derivative, dihydrohonokiol-B (DHH-B) [3'-(2-propenyl)-5-propyl-(1,1'-biphenyl)-2,4'-diaol], on ammonia-induced increases in the intracellular Cl(-) concentration ([Cl(-)](i)) were examined using primary cultured rat hippocampal neurons. DHH-B (1-100 ng/ml), but not an inactive isomer of honokiol, magnolol (100 ng/ml), dose-dependently inhibited the ammonia-induced increases in [Cl(-)](i) without any changes in the control [Cl(-)](i). Such an effect of DHH-B was blocked by a gamma-aminobutylic acid A (GABA(A)) and GABA(C) Cl(-) channel blocker, 100 microM picrotoxin, and a GABA(C) receptor blocker, 10 microM (1,2,5,6-tetrahydropyridine-4-yl)methylphosphinic acid, but not by a GABA(A) receptor blocker, 10 microM bicuculline. Further, a GABA(C) receptor agonist, 200 microM cis-4-aminocrotonic acid, but not a GABA(A) receptor agonist, 10 microM muscimol, mimicked the effect of DHH-B. Thus, DHH-B appears to protect neurons from the ammonia-induced increases in [Cl(-)](i) through GABA(C) receptor stimulation.     

Protease inhibitors (gebexate mesylate and ulinastatin) stimulate intracellular chemiluminescence in human neutrophils.

The effect of protease inhibitors on the intracellular production of free radicals was investigated by measuring chemiluminescence (CL) elicited from phagocytosed luminol-bound microspheres (Lumispheres) in human neutrophils stimulated with formylmethionyl-leucyl-phenylalanine (fMLP), interleukin-8 (IL-8), phorbol 12-myristate 13-acetate, or diacylglycerol. Both gabexate mesylate (Foy) and ulinastatin (Miraclid), urinary trypsin inhibitor, increased intracellular CL in a dose dependent manner. Compared to control buffer without protease inhibitor, gabexate mesylate (322 micrograms/ml) caused about a 10-fold increase in intracellular CL in stimulated neutrophils, and ulinastatin (3100 U/ml) a twofold increase in neutrophils stimulated with fMLP or IL-8. When the protease inhibitors were added to the cell suspension after the phagocytosis of lumispheres, CL responses rapidly increased again to the level which was observed when both protease inhibitors and neutrophil stimulants were incubated simultaneously. In contrast, extracellular release of oxygen metabolites from stimulated neutrophils, assayed by a conventional measurement of luminol-dependent CL, was reduced by the protease inhibitors in a dose dependent fashion. When luminol-unbound microspheres were incubated with neutrophils stimulated by fMLP in luminol solution, extracellular CL was almost completely inhibited by gabexate mesylate. These results indicate that the protease inhibitors enhance the generation of intracellular CL and suppress the extracellular release of free radicals.     

Activation of Human Monocytes for Enhanced Production of Interleukin 8 During Transendothelial Migration in Vitro

Interleukin-8 (IL-8) is a chemokine for polymorphonuclear leukocytes (PMNs) and lymphocytes, which promotes the extravasation of these inflammatory cells. In this study, we investigated IL-8 synthesis induced by the adhesive interaction between monocytes and endothelial cells during transmigration and the capacity of transmigrated monocytes to produce IL-8. Cocultured human monocytes and human umbilical vein endothelial cell (HUVEC) monolayers induced the synefgistic production of IL-8, compared with cultures of either monocytes or HUVEC monolayers alone. Coculture-induced IL-8 production almost doubled after HUVECs were stimulated with IL-1. The induced IL-8 mRNA expression was consistent with the protein data, indicating the de novo synthesis of IL-8 by the coculture. Monoclonal antibodies (mAbs) against IL-8 inhibited the transendothelial chemotactic activity of the supernatants for PMNs by 55%. Immunohistochemistry revealed that both adherent and transmigrated monocytes and unstimulated HUVECs expressed IL-8 protein, whereas nonadherent monocytes did little. Transmigrated monocytes spontaneously secreted a 3.8-fold greater amount of IL-8 than the initial monocytes. Coculture-induced IL-8 production was inhibited about 30% by polyclonal Abs against IL-, IL-1, or tumor necrosis factor , while it was not affected by mAbs against intercellular adhesion molecule 1 or vascular cell adhesion molecule 1. The results suggested that adhesive interaction during the transmigration of monocytes through HUVEC monolayers activates both cell types to produce IL-8 and that transmigrated monocytes are capable of producing ample IL-8.     

Retrospective survey of urea cycle disorders: Part 1. Clinical and laboratory observations of thirty-two Japanese male patients with ornithine transcarbamylase deficiency

In a retrospective survey done from 1978-1988 in Japan, 32 male patients with ornithine transcarbamylase (OTC) deficiency were identified. We classified a neonatal and 2 late-onset groups, depending on clinical manifestations and the age at onset; group 1 (0-28 days; N = 10), group 2 (29 days-5 years; N = 13), and group 3 (greater than 5 years; N = 9). Compared to findings in the group 2 patients, there was a higher rate of mortality and a higher incidence of mental retardation in association with a great decrease in enzyme activity in group 1. In group 3, the mortality rate and enzyme activities were similar to those in group 1. However, patients in this group were asymptomatic prior to the first episode. Enzyme activities were measured mostly in autopsy samples. The serum citrulline levels (enzyme product) were highest in this group. Thus, the mutant enzymes were apparently labile with greater activities in vivo than in vitro. Treatments, including a protein-restricted diet, arginine supplementation, and sodium benzoate administration, resulted in a favorable prognosis for survivors with partial enzyme deficiency. We wish to emphasize that the incidence of late onset of this disease is higher than heretofore considered.     

p53 protein overexpression and K-rascodon 12 mutation in pancreatic ductal carcinoma: Correlation with histologic factors

The correlation of p53 protein overexpression and the K-ras codon 12 mutatlon wlth histologlc type, grade of cytologic atypla, depth of lnvasion and other histologlc prognostic factors was studied In paraffin sectlons from 43 ductectatic-and 70 solid-type pancreatic ductal carcinomas. Overexpression of p53 was found in 23.3% (10143) of ductectatic carcinomas (17.2% of intraductal and 35.7% of lnvaslve carclnomas) and in 61.4% (43/70) of solid carcinomas. In ductectatic cancers, p53 overexpression was detected In 14.8% (4/27) of carcinomas wlth lowgrade atypla (CAL), 50.0% (5110) of carcinomas wlth high-grade atypla (CAH) and in 16.7% (In) of mixed low- and hlgh-grade cancers. In the last group, expression was restricted to an area of CAH. In solld cancers, p53 overexpression did not dlffer by histologic type or grade. Overexpresslon of p53 and K-ras mutatlons did not correlate with histologlc prognostic factors (lymphatic, venous and perineural Invasion, and lymph node metastasls) in ductectatlc and solld cancers or depth of invasion of solld carclnomas. Our data suggest that p53 alteratlon occurs at an early intraductal stage of solld carcinoma, irrespectlve of cellular atypla, but Is low in ductectatic CAL and becomes hlgher In ductectatlc CAH. K-ras mutatlon, present In a high percentage of tumors of all groups and not correlating with the factors above, showed no changes In frequency with tumor progression.     

Studies of bovine enterovirus structure by ultraviolet resonance Raman spectroscopy

The structural comparison of bovine enterovirus MZ468 strain before and after the heat treatment was studied by ultraviolet resonance Raman (UVRR) spectra excited at both 235 and 251 nm. The difference between full, heated full and purified empty particles, which were expected as an in vitro model of uncoating, were demonstrated. At 235 nm excitation, the Raman bands of the capsid protein dominated in all the UVRR spectra. The UVRR spectra of the empty particles exhibited non-homogenious broadening for tryptophan W3 band and W7 Fermi doublet bands, which were characteristics of hydrophobic environment, when compared with those of the full particles. The results indicates that some Trp indole rings of the full particles were packaged inside the viral capsids and not strained by virion assembly. On the other hand, the Raman bands assigned to guanine residues of the single stranded-RNA genome were enhanced strongly in the 251-nm excited UVRR spectrum. The spectral differences between the packaged (full particles) and the unpackaged virions (heated full particles) indicates that some guanine residues had strong hydrogen bonds in the full particles.     

Analysis of intestinal HLA-DR bound peptides and dysregulated immune responses to enteric flora in the pathogenesis of inflammatory bowel disease

Isolation of antigenic peptides from the MHC-groove has contributed to the understanding of T cell responses. However, these MHC-associated peptides have been isolated from various murine and human cell lines. The specific antigen responsible for the pathogenesis of inflammatory bowel disease is unknown. We examined antigenic peptides bound to the class II major histocompatibility complex (MHC) groove in human intestine by ion-trap tandem mass spectrometry equipped with online reverse-phase high performance liquid chromatography. We detected 55 parent proteins from 4 controls, 9 patients with ulcerative colitis, and 9 patients with Crohn's disease. The calculated molecular masses (m/z) of these peptides ranged from 874.4 to 2727.4, representing 10-26 amino acid residues. Fifty-one of these 55 parent proteins were exogenous proteins. Escherichia coli-, Saccharomyces cerevisiae-, and Caenorhabditis elegans-derived peptides were found frequently in patients with inflammatory bowel disease. The present results suggest that in vivo antigen processing by antigen-presenting cells and T lymphocytes in human intestine participate with exogenous antigen presentation. Increased immune responses against E. coli, S. cerevisiae and C. elegans found in patients with inflammatory bowel may participate as dysregulated immune responses to enteric flora in the pathogenesis of inflammatory bowel disease.