Stimulation of Bordetella pertussis adenylate cyclase toxin intoxication by its hemolysin domain.

The internalization of the N-terminal catalytic domain of Bordetella pertussis adenylate cyclase toxin (ACT) across the cytoplasmic membrane has been considered to occur independently from protein-protein interactions which can lead to oligomerization required for hemolytic activity by its C-terminal hemolysin domain. Here we report that when added in excess, this hemolysin domain stimulates the internalization, suggesting the involvement of protein-protein interactions in cell-invasive activity of ACT, as well as its hemolytic activity.

Development of the biologically active Guglielmi detachable coil for the treatment of cerebral aneurysms. Part II: an experimental study in a swine aneurysm model.

Background And Purpose: Ion implantation is a surface-modification technology that creates a borderless surface on protein-coated platinum; this change in physical and chemical properties on the surface of Guglielmi detachable coils (GDCs) appears to enhance cell proliferation and adhesion. Our purpose was to evaluate the effect of ion implantation on GDCs in an experimental aneurysm model.

Methods: GDCs were coated with either type I collagen, fibronectin, vitronectin, laminin, or fibrinogen.

Development of a biologically active Guglielmi detachable coil for the treatment of cerebral aneurysms. Part I: in vitro study.

Background And Purpose: Stronger cellular adhesion on the surface of endovascular devices promotes accelerated healing of aneurysms. The purpose of this in vitro study was to study the cellular interaction on the surface of bioactive Guglielmi detachable coils (GDCs) after using the surface-modification technology, ion implantation.

Methods: Polystyrene (PS) dishes and platinum plates were used to simulate a GDC surface.

Development of biologically active GDC for the treatment of cerebral aneurysms.

In Vitro Study: The surface of polystyrene dishes were treated either by: 1) collagen coating without ion implantation, or 2) collagen coating with ion implantation. Ne(+) implantation was performed on area 2 with fluences of 1 x 10(15) at an energy of 150 keV Bovine endothelial cells were cultured on the dishes and the resistance to detachment of cells was evalated with trypsin treatment. Experimental Aneurysm Study: GDCs were coated with either type I collagen, fibronectin, vitronectin, laminin or fibrinogen.

Characterization of the human dihydropyrimidinase-related protein 2 (DRP-2) gene.

The genes within the dihydropyrimidinase-related protein (DRP) family, were originally identified in humans by their homology to dihydropyrimidinase (DHP). Four members of this gene family, DRP-1, -2, -3 and -4, are expressed mainly in the fetal and neonatal brains of mammals and chickens, and have been implicated as intracellular signal transducers in the development of the nervous system. We isolated the human DRP-2 gene, and determined its transcriptional start site and exon/intron organization.

Epigallocatechin gallate and gallocatechin gallate in green tea catechins inhibit extracellular release of Vero toxin from enterohemorrhagic Escherichia coli O157:H7.

We studied the effects of six catechin derivatives (catechin, epigallocatechin, epicatechin, epicatechin gallate, epigallocatechin gallate (EGCg) and gallocatechin gallate (GCg)) in green tea on the production and extracellular release of Vero toxins (VTs) from enterohemorrhagic Escherichia coli (EHEC) cultured at 37 degrees C for 24 h. EGCg and GCg in the culture medium markedly inhibited extracellular VTs release from EHEC cells into the culture supernatant fluid at concentrations of 0.05 mg/ml or higher, as estimated by both the reversed passive latex agglutination assay and cytotoxic assay using Vero cells.

Release characteristics of endogenous constituents by exposure of small intestine to modified beta-cyclodextrins.

The aim of the present research is to characterize the leakage of intestinal constituents induced by beta-cyclodextrin (beta-CyD) derivatives using an in situ perfusion and an in vitro everted sac. The efficacy of 6-O-alpha-D-glucosyl (G1)- and 6-O-alpha-D-maltosyl (G2)-beta-CyDs as oral carriers was also compared with that of 2-hydroxypropyl-(HP1; average molar degree of substitution, 0.9) and 2,6-di-O-methyl (DM)-beta-CyDs.

Suppression of platelet aggregation by Bordetella pertussis adenylate cyclase toxin.

The effect of Bordetella pertussis adenylate cyclase toxin (ACT) on platelet aggregation was investigated. This cell-invasive adenylate cyclase completely suppressed ADP (10 microM)-induced aggregation of rabbit platelets at 3 micrograms/ml and strongly suppressed thrombin (0. 2 U/ml)-induced aggregation at 10 micrograms/ml.

Effect of sugar-modified beta-cyclodextrins on dissolution and absorption characteristics of phenytoin.

Inclusion complexes of phenytoin (DPH) with 6-O-alpha-D-glucosyl (G1)- and 6-O-alpha-D-maltosyl (G2)-beta-cyclodextrins (beta-CyDs) were prepared in a molecular mixing ratio of 1:1. The advantages of these preparations in terms of dissolution characteristics and the oral absorbency of DPH were evaluated in comparison with the known solid dispersions of polyvinylpyrrolidone K-30 and sodium deoxycholate (DC-Na). The results of a phase-solubility study indicated that G1- and G2-beta-CyDs provided higher solubility for DPH than 2-hydroxypropyl (HP)-beta-CyD.

Pharmacokinetic drug interactions between ampiroxicam and sulfaphenazole in rats.

The aim of the present study was to determine the effect of sulfaphenazole (SP) on the pharmacokinetics of ampiroxicam (AM) which is metabolized by cytochrome P-450 (CYP) 2C9, since SP is a potent inhibitor of CYP 2C9, and so a dramatic pharmacokinetic drug interaction between both drugs is assumed after dosing. Single intravenous and oral administrations of AM (5 and 7.5 mg/kg piroxicam equivalent, respectively) and SP (80 and 120 mg/kg, respectively) to rats did not significantly alter the elimination kinetics of AM and piroxicam (PX) converted from AM.

Adenovirally expressed basic fibroblast growth factor rescues photoreceptor cells in RCS rats.

Purpose: To evaluate the abilities of recombinant adenovirus carrying the basic fibroblast growth factor (bFGF) gene to (1) produce bFGF protein in vitro and (2) rescue retinal photoreceptors in Royal College of Surgeons (RCS) rats in vivo.

Methods: Cultured human retinal pigment epithelial cells were infected with one of the following two replication-deficient adenoviral vectors that drive inserted genes by beta-actin promoter with cytomegalovirus enhancer: AxCAJSbFGF, which expresses the human bFGF gene, and AxCAlacZ, carrying the cDNA of bacterial beta-galactosidase as a viral control. These viruses and recombinant bFGF protein were also injected into the subretinal space of RCS rats at the age of 21 days.

In vitro regioselective stability of beta-1-O- and 2-O-acyl glucuronides of naproxen and their covalent binding to human serum albumin.

beta-1-O- (NAG) and 2-O-glucuronides (2-isomer) of (S)-naproxen (NA) were prepared to determine which positional isomer(s) of the acyl glucuronide of NA is responsible for forming covalent adducts with human serum albumin (HSA). Their comparative stability and covalent binding adduct formation with HSA were investigated at pH 7.4 and at 37 degreesC.

Simultaneous determination of nicotinic acid and its metabolites in rat urine by micellar electrokinetic chromatography with photodiode array detection.

Nicotinic acid, nicotinamide and their possible metabolites were successfully separated within 17 min by micellar electrokinetic chromatography using 50 mM borate buffer (pH 9.0) containing 150 mM sodium dodecyl sulfate as the running buffer. Calibration curves for all compounds showed good linearity in a range of 5 microg/ml and 250 microg/ml with good correlation.

Enhancement of the oral bioavailability of phenytoin by N-acetylation and absorptive characteristics.

To improve the absorbability of phenytoin (DPH), a prodrug, N-acetyl-DPH (EDPH), was synthesized, and the absorptive characteristics and pharmacokinetics of the prodrug were evaluated in rats. EDPH was rapidly hydrolyzed to DPH in the intestinal fluid and the mucosa (rate constant, 0.055 and 0.

Lysozyme-containing renal tubular hyaline droplets in F344 rats bearing a rat fibrosarcoma-derived transplantable tumor.

Renal tubular hyaline droplets developed in male and female F344 rats bearing a rat fibrosarcoma-derived transplantable tumor (SS). The droplets accumulated exclusively in the proximal renal tubular epithelia as eosinophilic granules of various sizes in hematoxylin and eosin-stained sections. The granules stained bright red with azan-Mallory stain.

A photosystem I reaction center driven by chlorophyll d in oxygenic photosynthesis.

A far-red type of oxygenic photosynthesis was discovered in Acaryochloris marina, a recently found marine prokaryote that produces an atypical pigment chlorophyll d (Chl d). The purified photosystem I reaction center complex of A. marina contained 180 Chl d per 1 Chl a with PsaA-F, -L, -K, and two extra polypeptides.

Membrane-bound cytochrome cz couples quinol oxidoreductase to the P840 reaction center complex in isolated membranes of the green sulfur bacterium Chlorobium tepidum.

The reaction of quinol oxidoreductase and membrane-bound c-type cytochromes was studied in chlorosome-depleted membranes isolated from Chlorobium tepidum. Rapid oxidations of c-type cytochromes were detected after flash excitation. Their re-reductions occurred in parallel with the reduction of cytochrome b, especially in the presence of antimycin A, whereas reductions of both cytochromes c and b were suppressed by added stigmatellin.

Pharmacokinetics of aniracetam and its metabolites in rats.

The pharmacokinetics of aniracetam (AP), a new cognitive performance enhancer, and its main metabolites was investigated after intravenous (iv) and oral administrations to rat. The plasma levels of AP, 4-p-anisamidobutyric acid (ABA), and p-anisic acid (AA) were determined simultaneously by the HPLC method. The plasma concentrations of the parent drug and ABA quickly declined in a biexponential manner, with rapid terminal decay and a small mean residence time.

Enterohemorrhagic Escherichia coli O157:H7 present in radish sprouts.

Using cultivation, immunofluorescence microscopy, and scanning electron microscopy, we demonstrated the presence of viable enterohemorrhagic Escherichia coli O157:H7 not only on the outer surfaces but also in the inner tissues and stomata of cotyledons of radish sprouts grown from seeds experimentally contaminated with the bacterium. HgCl2 treatment of the outer surface of the hypocotyl did not kill the contaminating bacteria, which emphasized the importance of either using seeds free from E. coli O157:H7 in the production of radish sprouts or heating the sprouts before they are eaten.

Effects of nitric oxide synthase inhibitor on intraocular pressure and ocular inflammation following laser irradiation in rabbits.

Purpose: To examine the effects of nitric oxide synthase (NOS) inhibitors on intraocular pressure (IOP) and ocular inflammation following laser irradiation of the rabbit iris, and to investigate the involvement of nitric oxide (NO).

Methods: Thirty min after the intravenous administration of a nonselective inhibitor of NOS, N omega-nitro-L-arginine methyl ester (L-NAME, 1-100 mg/kg), or a selective inhibitor of iNOS, aminoguanidine (AG, 100 mg/kg), Q-switched Nd:YAG laser irradiation was applied to the iris of albino rabbits at an energy level of 48 mJ. IOP was measured prior to and for 24 h after irradiation.

Water Wettability and Zeta-Potential of Polystyrene Surface Modified by Ne or Na Implantation.

A study has been made of the modification of the wettability and the surface potential of polystyrene by ion bombardment and implantation. Substrates used were polystyrene (PS) dishes. Ne bombardment and Naion implantation were performed at energies of 50 and 150 keV with fluences between 1 x 10(14) to 1 x 10(17) ions/cm2.

Transient expression of PG-M/versican, a large chondroitin sulfate proteoglycan in developing chicken retina.

We previously showed the expression of PG-M/versican in embryonic chicken retina. In this study, we characterized the alternatively spliced forms of PG-M/versican and their developmental regulation to investigate the implication of PG-M/versican in neurite outgrowth from retinal cells during development. On day 5, the immunolocalization of PG-M was first observed at the inner surface of neural retina.

Characteristics of a rat fibrosarcoma-derived transplantable tumour line (SS) and cultured cell lines (SS-P and SS-A3-1) showing myofibroblastic and histiocytic phenotypes.

A transplantable tumour line (SS) was established in syngeneic rats from a spontaneous fibrosarcoma that had arisen in the submandibular salivary gland of a 24-month-old male F344 rat. A cell line (SS-P) was induced from SS, and a cloned cell line (SS-A3-1) was isolated from SS-P. The primary tumour consisted of oval to spindle-shaped cells arranged in bundles with abundant collagen fibres; ultrastructurally, neoplastic cells exhibited fusiform morphology with prominent rough endoplasmic reticulum.