Control of and Mechanisms for Room Temperature Visible light Emission from Silicon Nanostructures in SiO2 formed by Si+ Ion Implantation

Implantation of Si+ ions into thermal oxides grown on silicon has been used to synthesise a two phase structure consisting of Si nanocrystals in a SiO2 matrix. Various processing conditions have been used in order to modify the size and population distributions of the Si inclusions. Photoluminescence spectra have been recorded from samples annealed in nitrogen, forming gas and oxygen. Both red and blue shifts of the luminescence peaks have been observed. It is concluded that the photoluminescence is a consequence of the effects of quantum confinement but is also dependent on the presence of irradiation-induced defects or Si/SiO2 interface states.

Function of surfactants in hair dyeing by oxidation dyes 2. Effect on formation of oxidation dyes by p-aminophenol and 5-amino-o-cresol in dye bath(1)

The effect of surfactants on an oxidation-hair-dye-formation reaction in a dye bath was studied in order to learn the mechanism of the effect of surfactants on the dyeability of hair by the oxidation dye. The dye-formation behaviours for the p-aminophenol and 5-amino-o-cresol system with the surfactants, of which the hydrophilic parts have different charges, were compared changing the concentration of surfactants. It was found that the same dyes are produced, regardless of the charge of surfactants added, and the rate of dye produced in the dyebath is increased in the presence of surfactants. The order of the production rate is, with an anionic surfactant > with non-ionic surfactant > with cationic surfactant > without surfactant. The relation between the dyeability of hair and the rate of dye produced in the dyebath in the presence of surfactants is not found. The major factor governing the dyeability of hair is different from the mechanism of the increased dye in the solution. It was also found that the dye-formation rate is increased by immersing hair into the reaction solution, and hair works as an accelerator for the dye-formation reaction.

Apolipoprotein A-I concentration in tears in diabetic retinopathy

BACKGROUND

Apolipoprotein concentrations in reflex tears from healthy and noninsulin-dependent diabetes mellitus (NIDDM) subjects were measured and correlated with the stage of diabetic retinopathy.

METHODS AND RESULTS

The apolipoprotein A-I (apo A-I) concentrations in the tears from NIDDM patients with retinopathy were significantly higher than those from patients with no or negligible retinopathy (P<0.05), and apo A-I was not detected in healthy subjects by Western blotting. No reactive band was detected on apo A-I by Western blotting for nitrotyrosine, a marker for peroxynitrite oxidation of the tear proteins. Apo A-I concentration in tears was significantly correlated with the stage of retinopathy (r= 0.598, n = 59, P < 0.001). No apo A-I gene expression was detected in the conjunctiva by reverse transcription polymerase chain reaction.

CONCLUSIONS

We conclude that there is increased secretion of native apo A-I from the main lacrimal gland in patients with advanced diabetic retinopathy.

Serum lipid metabolism abnormalities and change in lipoprotein contents in patients with advanced-stage renal disease

BACKGROUND

Arteriosclerosis is the major cause of death in patients with chronic renal failure. There is much interest in the lipid metabolism of patients treated with hemodialysis.

METHODS

We analyzed low-density lipoproteins (LDL) and high-density lipoproteins (HDL) in chronic renal failure (CRF) patients according to patients on hemodialysis (HD), patients with diabetic nephropathy before initiation of dialysis (DN), and patients with chronic glomerulonephritis in the conservative stage (CGN); and compared the lipid metabolic abnormalities in patients on hemodialysis and those not yet on hemodialysis. We also analyzed the qualitative abnormalities of LDL and HDL and their relationship with the pathological stages.

RESULTS

Electrophoretic patterns identified small LDL particles and small HDL particles in the three groups, and the degree of denaturation was more enhanced in CRF patients in the conservative stage than in HD patients. For LDL susceptibility to oxidation LDL (oxLDL) by addition of Cu(2+), the lag time was approximately 57 min in healthy controls and CGN patients, but was prolonged to approximately 75 min in HD and DN patients. For HDL susceptibility to oxidation HDL (oxHDL), HD, DN and CGN patients showed lag times shorter than those found in healthy control subjects. These results showed that LDL and HDL in the serum of CRF patients were in a state of enhanced susceptibility to oxidative modification. In Western blot analysis using anti-human-denatured LDL and anti-human-oxidized HDL monoclonal antibodies, bands of low molecular oxLDL at 150-197 kDa were detected in all CRF patients, with marked tailing in CGN patients. Similarly, bands of small oxHDL particles at 110 and 120 kDa were found in HD, DN and CGN patients.

CONCLUSIONS

Oxidative modification of both LDL and HDL occurs in patients with advanced CRF resulting in small lipoproteins. Increased production of oxLDL and oxHDL is the main cause of lipid metabolic abnormality in CRF patients.

Characterizations of recombinant human tartrate-resistant acid phosphatase from osteosarcoma: comparison study between recombinant and placental proteins

We cloned the human tartrate-resistant acid phosphatase (TRAP) gene from human osteosarcoma cells (Saos-2), and produced recombinant human TRAP (rhTRAP) using a baculovirus vector expression system. RhTRAP from Sf9 culture medium was purified by cation exchange chromatography, gel filtration and affinity chromatography. The molecular mass and amino acid composition of the rhTRAP were consistent with the deduced amino acid composition from the TRAP gene. The N-terminal amino acid sequence of rhTRAP was identical to that of TRAP purified from osteoclastoma and hairy cell leukemia spleen. The monoclonal antibodies generated against rhTRAP also reacted to human placental TRAP (pTRAP). The optimum pH of rhTRAP and pTRAP were pH 5.0-5.5 and pH 6.0-6.5, respectively. The enzymatic activities of rhTRAP and pTRAP were activated by reducing agents such as 2-mercaptoethanol, dithiothreitol and ascorbic acid. The activities of rhTRAP and pTRAP were enhanced by Fe2+ ions, but were inhibited by Fe3+ ions. The present results indicate that rhTRAP has similar properties to the native human TRAP, and suggest that the enhancement of TRAP activity by reducing agents might be expressed via the reduction of Fe ions at the metal center.

Expression of pyrimidine 5'-nucleotidase subclass I during erythrocyte maturation in rats

The subclass I enzyme of rat pyrimidine 5'-nucleotidase (P5N-I), which preferentially hydrolyzes (deoxy)CMP and UMP, is distributed specifically in red blood cells (RBCs), and its activity increases approximately six-fold as compared to the control value after erythropoietic induction by phenylhydrazine administration. In this study, we detected rat P5N-I protein by using antibodies against the chicken P5N-I enzyme. The molecular mass of rat P5N-I was approximately 37 kDa, as estimated by gel filtration chromatography and Western blot analysis. The pI value of the enzyme was approximately 5.7. This protein band was detected only in RBC lysate extract, i.e., not in cytosol from the erythropoietic spleen. Protein mass of the P5N-I enzyme, estimated by immunoblot analysis, was increased in proportion to the enzyme activity after erythropoietic induction in rats. No phosphorylation of the enzyme protein was detected by immunoblot analysis with anti-phosphoserine or anti-phosphotyrosine antibody. In conclusion, these findings indicate that the rat P5N-I enzyme is expressed specifically in reticulocytes and may therefore be essential in the maturation process of rat erythrocytes.

Atypical alkaline phosphatase isozymes in serum and urine of patients with renal failure

BACKGROUND

Alkaline phosphatases (ALPs) originating from different organs are frequently detected in the serum and urine of patients with renal failure.

METHODS

We investigated the characteristics of ALPs in the serum and urine of 108 patients with chronic renal failure (CRF) and of 106 healthy control subjects.

RESULTS

In polyacrylamide gel electrophoresis, three atypical ALP bands in serum of patients were designated as atypical-s1, -s2 and -s3, respectively. In contrast, five atypical bands (u1, u2, u3, u4 and u5) were detected in the urine of patients. The atypical ALPs were electrophoretically isolated and assayed to determine their biochemical properties, i.e., neuraminidase sensitivity, heat stability, reactivity to anti-intestinal or anti-tissue nonspecific ALP antibodies, molecular sizes and sugar chain heterogeneities. From these results, we found that atypical-s1 and -s2 were the intestinal-type ALP, while s3 was the tissue-unspecific type ALP. Atypical-u1, -u2 and -u3 were high-molecular type ALPs, which we suggested as the ones that originated from the intestine. Atypical-u4, a tissue-unspecific type ALP, was detected with considerable frequency in the urine of patients. In patients with CRF, the appearance of these atypical ALPs was accompanied by a deterioration of the creatinine clearance.

CONCLUSIONS

The appearance of atypical ALPs in the serum and urine of patients with CRF may be a useful marker for renal disease.

Glycated high-density lipoprotein induces apoptosis of endothelial cells via a mitochondrial dysfunction

Glycation of plasma proteins may contribute to an excess risk of developing atherosclerosis in patients with diabetes mellitus. Although it is believed that high-density lipoprotein (HDL) is nonenzymatically glycosylated at an increased level in diabetic individuals, little is known about a possible linkage between glycated HDL and endothelium dysfunction in diabetes. This study set out to clarify whether glucose-modified HDL affects the function of endothelial cells by examining the apoptosis of cultured human aortic endothelial cells (HAECs) exposed to a glycated-oxidized HDL (gly-ox-HDL) prepared in vitro. Incubation of HAECs with 100 microg/ml of gly-ox-HDL for 48 h showed apoptotic features, such as cell shrinkage, membrane blebbing, and concentration and fragmentation of the nucleus, and the degree of apoptosis was dose-dependent on the glucose used in the preparation of gly-ox-HDL. Stimulation of HAECs with gly-ox-HDL elicited a marked increase in caspase 3 activity and the expressions of active caspase 3 and caspase 9, whereas concomitant treatment with a caspase 3 inhibitor significantly blocked gly-ox-HDL-induced apoptosis of HAECs. The release of cytochrome c into cytosols markedly increased in HAECs during the treatment with gly-ox-HDL. The increased expressions of Bax and Bad were detected in HAECs incubated for 24 h with gly-ox-HDL, but gly-ox-HDL failed to interfere with the expression of Bcl-2 and Bcl-x. Moreover, in vitro experiments with HDL (gly-HDL) glycated in the presence of 2 mM EDTA and Cu(2+)-oxidized HDL suggested that the apoptotic effect of gly-ox-HDL on endothelial cells might be due to an additional oxidative modification of gly-HDL. Taken altogether, additional oxidation of HDL under hyperglycemic conditions may induce endothelial apoptosis through a mitochondrial dysfunction, following the deterioration of vascular function.

Modulation of reactive oxygen species in endothelial cells by peroxynitrite-treated lipoproteins

Peroxynitrite has been implicated in the oxidative modification of low-density lipoprotein (LDL) particles, and nitrotyrosine residues in the LDL have been detected in atherosclerotic plaques. Studies have suggested that lipoproteins modified by peroxynitrite lead to the onset of atherosclerotic vascular disease. We therefore prepared in vitro lipoproteins oxidatively modified by peroxynitrite (NO(2)-lipoprotein) and investigated the effect of NO(2)-lipoprotein on the viability of cultured endothelial cells. After exposure of a high-density lipoprotein (HDL) to peroxynitrite, some intermolecular complexes of apolipoproteins in HDL were detected on immunoblotting with monoclonal antibodies against apolipoprotein AI and AII, suggesting that nitration of HDL by peroxynitrite causes intermolecular cross-linking of the apolipoproteins in the particles. Treatment with 1 mM peroxynitrite increased the 3-nitrotyrosine level to 28.5 mmol/mol of tyrosine residues in the prepared NO(2)-HDL, as quantitated by HPLC, and the amount in NO(2)-lipoprotein depended on the peroxynitrite concentration. HDL exhibited a shorter lag phase and the reaction plateaued more rapidly than that with LDL. To clarify whether or not NO(2)-lipoproteins affect the function of endothelial cells, we first examined the viability of cultured human aortic endothelial cells (HAECs) exposed to NO(2)-lipoproteins. Incubation with either NO(2)-HDL or NO(2)-LDL significantly reduced the HAEC viability at 72 h. The results of RT-PCR and Western blotting showed that NO(2)-HDL markedly suppressed at 48 h not only the expressed levels of mRNA and protein but also the activity of catalase in HAECs. In contrast, NO(2)-LDL significantly reduced the expression and activity of Cu(2+),Zn(2+)-superoxide dismutase (CuZn-SOD) in the cells. Neither NO(2)-HDL nor NO(2)-LDL interfered with nitric oxide production or expression of cyclooxygenases and NADPH oxidase in HAECs. Increased radical production in NO(2)-lipoprotein-treated HAECs implied that reactive oxygen species such as superoxide anions and hydroxyl radicals may contribute to the mechanism of the toxic effect induced in endothelial cells by NO(2)-lipoprotein. Overall, NO(2)-lipoprotein may lead to deterioration of the vascular function through these endothelial cell responses.

alpha-Amylase expressed in human liver is encoded by the AMY-2B gene identified in tumorous tissues

BACKGROUND

An alpha-Amylase in human liver is detected with an anti-human salivary amylase antibody, but the enzyme activity is very low. We previously found that the rat liver contained an amylase which differed from the enzyme of mice. In this study, we characterized the human liver amylases biochemically and immunohistochermically.

METHODS AND RESULTS

Although the amylase activity of human liver was much lower than that of rat, protein moiety and sugar chains of the human amylase were identified as similar to the rat liver enzyme with an anti-human salivary amylase antibody and by concanavalin A (Con A) affinity chromatography. Liver amylases from human and rat were the same size, 50 kDa, on Western blot analysis and had the same isoelectric points. The cytoplasm of hepatocytes was moderately stained immunohistochemically with the anti-human salivary amylase antibody. Intrahepatic bile ducts were also stained weak-to-moderately. RT-PCR, with a specific primer for the consensus sequence of human amylases, amplified a single 474-bp product from the human liver total RNA. The PCR product was sequenced and referred to the homology. Thirteen bases in the 434-bp fragment of the human liver amylase differed from the corresponding region of the AMY-1 gene transcript and the deduced amino acid sequence differed at five residues. The human liver amylase cDNA sequence was identical to the corresponding cDNA of the AMY-2B, which was known to expressed in tumorous tissues. In situ hybridization revealed the expression of AMY-2B mRNA in non-tumorous human liver.

CONCLUSIONS

The present results suggest the possibility that a novel amylase detected in tumorous tissues and encoded by the AMY-2B gene is a liver-specific amylase expressed in the human liver.

Chicken erythrocyte pyrimidine 5'-nucleotidase: purification and characterization of the subclass I enzyme

Nucleotidase activities resembling subclass I and subclass II of human pyrimidine 5'-nucleotidases (P5N) were detected in chicken red blood cells (RBCs). In chicken RBCs from untreated controls, the activity of the subclass II enzyme was about one third of that of subclass I enzyme, whereas that ratio was approximately 5:1 in rat or human RBCs. The subclass I activity in chicken RBCs was increased 5- to 6-fold upon erythropoietic induction by phenylhydrazine administration, but the subclass II activity did not increase under these conditions. The subclass I enzyme was purified to near homogeneity. Its molecular mass was about 35 kDa as estimated by gel filtration and SDS-polyacrylamide gel electrophoresis. Its N-terminal 12 amino acids, PEFQKKTVHIKD, were also determined. The catalytic properties of the subclass I enzyme were very similar to those of the human enzyme with regard to substrate (preferential hydrolysis of CMP, dCMP, UMP), Km values, optimum pH, and metal ion requirements. Antibodies against chicken P5N subclass I were raised in rats. The chicken P5N-I as well as the rat P5N-I proteins could be detected by antibodies in Western blot analyses, but not the P5N-II proteins. These findings indicate that P5N subclass I may have an important function in chicken erythropoiesis.

The ligands/activators for peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARgamma increase Cu2+,Zn2+-superoxide dismutase and decrease p22phox message expressions in primary endothelial cells

We examined the effects of a variety of ligands/activators of the peroxisome proliferator-activated receptor (PPAR) on the expression of the superoxide scavenger enzyme, Cu2+,Zn2+-superoxide dismutase (CuZn-SOD), and the superoxide generating enzyme nicotinamide adenine dinucleotide phosphate (reduced form) (NADPH) oxidase in primary cultures of human umbilical vein endothelial cells (HUVEC) and human aorta endothelial cells (HAEC). Our data show that 3 types of PPARs, PPARalpha, PPARbeta/delta/Nuc1, and PPARgamma are expressed in endothelial cells. Bezafibrate, which is a ligand/activator for PPARalpha, increased the CuZn-SOD gene expression and protein levels in endothelial cells. Troglitazone and pioglitazone, which are ligands/activators for PPARgamma, also induced PPARalpha gene and protein expression and increased CuZn-SOD gene expression and protein levels in addition to increasing PPARgamma gene and protein expression in endothelial cells. Moreover, with treatment of monounsaturated and polyunsaturated fatty acids (PUFA), the CuZn-SOD mRNA levels were positively correlated with PPARalpha mRNA levels (r = .872, P < .0001) in primary endothelial cells. In addition, the phorbol myristate acetate (PMA)-stimulated or PMA-nonstimulated 22-kd a-subunit (p22phox) mRNA levels and 47-kd a-subunit (p47phox) protein levels in NADPH oxidase were decreased by treatment with PPARalpha and PPARgamma ligands/activators. These results suggest that PPARalpha and PPARgamma gene and protein expression in endothelial cells may play a physiologic role as radical scavengers, although the details of these mechanisms remain to be established.

Effects of prosthetic valve placement on mitral annular dynamics and the left ventricular base

Insertion of a rigid mitral prosthesis impairs the function of the mitral annulus and induces systolic narrowing of the left ventricular outflow tract (LVOT). To study this mechanism, we investigated dynamic changes in the left ventricular (LV) base, which consists of the mitral annulus and LVOT orifice. In seven patients with mechanical mitral valve prostheses and eight normal subjects, the image of the LV base was reconstructed three-dimensionally and its dynamic change during systole was studied. In the patients, the rigid prosthetic valve (=mitral annulus) tilted toward the left ventricle with a hinge point at the posterior mitral annulus during systole. The left ventricular base exhibited contraction, but the size of the prosthetic valve was constant. As a consequence, the prosthetic valve occupied more of the left ventricular base, which resulted in narrowing of the LVOT. In the normal subjects, the mitral annulus did not interfere with the region of the LVOT orifice during systole as the mitral annulus underwent both dorsiflexion and contraction. Thus, fixation of the mitral annulus induces an anti-physiologic motion of the annulus. Conscious preservation of annular flexibility in mitral valve surgery is important in avoiding potential dynamic LVOT obstruction.

Expression of alpha-amylase gene in rat liver: liver-specific amylase has a high affinity to glycogen

The reactivity of rat liver alpha-amylases with maltotriose (G3), maltopentose (G5) and glycogen has been investigated. Liver amylases were found to be glycosylated and to have a molecular mass of 50 kDa by Western blotting using an anti-human salivary amylase antibody. The glycosylated liver amylases were found to be capable of G3- and G5-hydrolysis and of glucose formation, as demonstrated by thin-layer chromatography. When the amylase preparation was exposed to different concentrations of glycogen and run on a cellulose acetate membrane, the mobilities of rat liver amylases significantly decreased with tailing directly from the point of origin. In contrast, rat salivary amylases were not so much. These results indicate that rat liver amylases have a strong affinity to glycogen. We confirmed the expression of liver-specific amylases in rat liver by reverse transcriptional-polymerase chain reaction (RT-PCR); PCR products showed one band of an expected size of 474 bp using primers tested in the present study. A partial nucleotide sequence was then determined. When compared with the gene of mouse liver amylase, the substitution of 26 bases out of 434 bases was elucidated. The present data demonstrate the presence of liver-specific amylases in rats.

[Comparison of the morphology and the reactivity of Chlamydia pneumoniae isolated in north-Kanto Area, Ibaraki Prefecture, Japan]

To compare the morphology among Chlamydia pneumoniae (C. pneumoniae), strain TW183 and strains which were isolated in the area of Kasumigaura, Ibaraki from 1992 to 1995. C. pneumoniae were infected on HL cell monolayers and cultured in 5% CO2 at 35.5 degrees C for about 60 hrs. The cells were harvested and fixed with 2.5% glutaraldehyde, and then the regular procedure for observation of Chlamydia in inclusion by transmission electron microscope was performed. Immunoblot assay was carried out by using highly and partially purified C. pneumoniae TW183 and 4 isolates with partial purification as antigens. The results were as follows: the shape of TW183 and the isolates included pear and round shapes, respectively. Immunoblotting profiles were the same in terms of band-formation patterns with the serum from a patient infected with C. pneumoniae. These results may indicate that the round shape of C. pneumoniae elementary body (EB) is predominantly pandemic in Japan, although pear-shaped EBs of C. pneumoniae were found in the neighboring prefecture of Chiba.

Annular stabilization in mitral repair without a prosthetic ring

BACKGROUND AND AIM OF THE STUDY

Annular stability is not guaranteed after mitral repair without a prosthetic ring. We introduce a newly developed plication technique and detail its stabilizing effect on the mitral annulus after Gerbode plasty.

METHODS

Patients suffered degenerative mitral valve prolapse with chordal rupture restricted to the middle scallop of the posterior leaflet. Between 1986 and 1997, 102 patients underwent Gerbode plasty with or without annular reinforcement with a pericardial strip or modified Paneth plasty (group C). The mean (+/- SD) follow up was 70.4 +/- 41.1 months. Since 1996, 32 patients have undergone a newly developed annuloplasty technique (group N), where a pericardial strip was tightly anchored to the bilateral trigones and posterior annulus, which was folded by Gerbode plasty. With the final anchoring suture the intention was to prevent plication breakdown of this portion. Mean follow up for this group was 17.6 +/- 7.1 months. Progression of mitral regurgitation after surgery in both groups was studied.

RESULTS

In group C, postoperative progression of mitral valve regurgitation occurred in 41.1% of patients (5.9% to grade 1, 17.6% to grade 2, 17.6% to grade 3). Among these patients, reoperation was due to plication breakdown of the Gerbode plasty in six cases (5.9%), and to either chordal rupture or annular dilatation in 10 cases each (9.8%). In contrast, no reoperation due to recurrent severe mitral regurgitation was needed in group N. Progression of mitral regurgitation after surgery was seen in six patients (two to grade 1; four to grade 2).

CONCLUSION

The newly developed annuloplasty technique may be useful in stabilizing the mitral annulus after Gerbode plasty.

Induction of rat alkaline phosphatase isozymes bearing a glycan-phosphatidylinositol anchor modified by in vivo treatment with a benzimidazole derivative linked to ethylbenzene

Serum alkaline phosphatase (ALP) is detected in soluble-form as a result of translocation from the membrane site by cleavage at the glycosyl-phosphatidylinositol moiety (GPI anchor). It is known that membrane-bound ALP (mALP) can be detected in serum in certain pathological and physiological conditions, and that it can be solubilized in vitro to soluble-ALP (sALP) by phosphatidylinositol-specific phospholipase C (PIPLC), phospholipase D, bile salt, detergent, etc. We observed a marked increase in ALP activity in the serum of rats given a benzimidazole derivative by gavage, and detected it as slow-migrating ALPs (SM-ALPs), which were mALP-like but resistant to PIPLC and n-butanol treatment on disc PAGE. On the other hand, ficin treatment made SM-ALPs shift to the sALP position. The molecular size of the SM-ALPs was smaller than that of sALP on sodium dodecyl sulphide-polyacrylamide slab-gel electrophoresis (SDS-PAGE), and immunoreactivity revealed the intestinal type. SM-ALPs were also detected in the duodenum and jejunum. The main sugar chain structure of SM-ALPs was the biantennary complex-type, which was coincided with intestinal sALP sugar chain. These results suggest that intestinal ALPs induced by the benzimidazole derivative were modified in their C-terminus or GPI anchor region and modification of this region may also participate in translocation into the bloodstream.

[Nose bleeds and nitric oxide in the nose]

Most of the nitric oxide (NO) in expiratory air is produced by the nose and its accessory sinuses, and nasal allergies related to NO have been often reported. In the present study, we postulated that nose bleeds may be somehow related to reactive oxygen species. The expression of NO synthase (NOS) by the nasal mucosa was evaluated using the RT-PCR method, and the concentration of NO in air expired through the nose was measured. The activity of superoxide dismutase, which scavenges superoxide anions, was also evaluated. The genetic expression of iNOS was observed in the nasal mucosa, and a significantly lower level of expression was noted in subjects with a nosebleed, compared to that of the controls. This result was interpreted as indicating a decrease in NO levels as a result of the nosebleed, leading to an elevation in blood pressure. Transient elevations in blood pressure caused by oxidative stress may lead to the rupture of nasal vessels if hypertension preexists. Serum levels of superoxide dismutase increased significantly in subjects with nose bleeds. This finding might be related to the activity of the superoxide anion, which is released in large amounts during nose bleeds. Serum superoxide dismutase levels increase in response to the high concentration of superoxide anions. The concentration of NO in air expired through the nose was significantly lower in subjects with nose bleeds, compared to that of the control subjects. We suggest that NO production decreases in subjects experiencing nose bleeds and that this reduction is induced by preexisting hypertension and injury from reactive oxygen species, contributing to the resulting nose bleed.

Glycosylated salivary alpha-amylases are capable of maltotriose hydrolysis and glucose formation

The physiological and/or clinical significance of sugar chains in human salivary alpha-amylase was investigated in terms of substrate-specificity for synthesized malto-oligosaccharides. Glycosylated and non-glycosylated alpha-amylases were prepared on a Sephacryl S-200 column, in which the amylases were separated into four fractions from the different affinities for Sephacryl: fraction I, amylases bearing sugar chains with sialic acid; fraction II, amylases bearing sugar chains without sialic acid; fractions III and IV, non-glycosylated amylases. These were classified according to the differences in their affinities for lectins, molecular sizes and isoelectric points. The inhibitory effect of maltotriose (G3) on starch hydrolysis of the amylase fraction, suggests that starch and G3 can be the substrate for glycosylated amylase, and that the glycosylated amylases are capable of G3 hydrolysis for conversion into maltose and glucose. Using malto-oligosaccharides, G3, G4, G5 and G7, as substrates, the substrate-specificities and G3/G5 ratio of amylase activities in the four fractions were examined. Maltopentaose, G5, is routinely used as a substrate for alpha-amylase, and then we assumed that both glycosylated and non-glycosylated amylases react with G5. Moreover, the results indicate that the glycosylated amylases clearly had a higher capacity for G3 hydrolysis than the non-glycosylated amylases, although no substrate preference of either type of amylase was observed among G4, G5 and G7. Glycosylated amylases have the capacity for glucose formation from malto-oligosaccharides.

Lipophilic HMG-CoA reductase inhibitor has an anti-inflammatory effect: reduction of MRNA levels for interleukin-1beta, interleukin-6, cyclooxygenase-2, and p22phox by regulation of peroxisome proliferator-activated receptor alpha (PPARalpha) in primary endothelial cells

We examined the effects of four 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (pravastatin, simvastatin, fluvastatin, and cerivastatin) on the production and expression of inflammatory cytokines and on enzyme expression involving prostaglandin and superoxide production in cultured human umbilical vein endothelial cells (HUVEC). All HMG-CoA reductase inhibitors significantly reduced interleukin-1beta and -6 mRNA expression and their protein levels in the culture medium, and also inhibited cyclooxygenase-2 mRNA expression and their protein levels. And these drugs induced peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARgamma mRNA expression and their protein levels in HUVEC and hepatocyte. Moreover, the mRNA levels of p22phox, a 22-kD subunit and the protein levels of p47phox, a 47-kD subunit of nicotine adenine dinucleotide phosphate (NADPH) oxidase, was decreased by treatment with either simvastatin, fluvastatin or cerivastatin, and this effect was reversed by mevalonate, geranylgeraniol, farnesol, and cholesterol. The changes induced by HMG-CoA reductase inhibitors might be due to regulation of cellular cholesterol content level, cellular cholesterol metabolic pathway, and cellular PPARalpha activity, which was related with inflammation. This unique anti-inflammatory effect in addition to its hypolipidemic action, may be beneficial in preventing the vascular complications that are induced by hyperlipidemia.

Nitric oxide-related compounds in patients with congenital heart defects and pulmonary hypertension

BACKGROUND

The relationship between blood levels of nitric oxide (NO)-related compounds in patients with congenital heart defects (CHD) and degree of pulmonary hypertension (PH) has not yet been described.

METHODS

Thirty-six patients (aged 6 months to 19 years) with CHD were divided into three groups on the basis of their hemodynamic characteristics: group 1 (control, n = 5), left-to-right shunt (-) without PH (pulmonary to systemic artery peak pressure ratio, Pp/Ps < 0.4); group 2 (n = 14), left-to-right shunt (+) without PH; group 3 (n = 17), left-to-right shunt (+) with PH (Pp/Ps > 0.4). Blood samples were obtained from the right atrium, pulmonary artery, left atrium or pulmonary capillary wedge and aorta during cardiac catheterization. All NO-related compounds in whole blood were measured by chemiluminescent assay using Sievers NO analyzer.

RESULTS

The sampling site had no significant impact on NO-related compound levels. However, the patients with PH (group 3) had significantly higher (P < 0.01) blood levels of NO-related compounds (117.3 +/- 14.7 mumol/L) than the patients without PH (groups 1 and 2, 23.9 +/- 3.2 and 38.4 +/- 4.8 mumol/L, respectively). In addition, pulmonary artery resistance (Rp) values of less than 6 Wood U/m2 were directly correlated with levels of NO-related compounds, whereas Rp values greater than 6 Wood U/m2 were inversely correlated with blood levels of NO-related compounds.

CONCLUSION

The present results suggest that the hemodynamic status of the pulmonary circulation in CHD affects, at least partly, blood levels of NO-related compounds.

[Expression of reactive oxygen-species related enzymes in endothelial cells stimulated with glycated lipoproteins]

Glycated lipoproteins, which elevate the blood in diabetic patients, cause direct attenuation of endothelial function. Increased glycation of apolipoproteins may play a trigger role in the accelerated development of atherosclerosis in the patient with diabetes. Here we assessed whether glycated lipoproteins affect on the endothelial function with particular emphasis on the role of reactive oxygen species in vitro. Incubation of human aortic endothelial cells(HAEC) with glycated LDL had little influence on the expression of antioxidant enzymes such as nitric oxide synthase(NOS), Cu2+Zn(2+)-superoxide dismutase (Cu2+Zn(2+)-SOD), catalase, and p22 phox in the cells. In contrast, exposure of glycated HDL induced a marked decrease of Cu2+Zn(2+)-SOD, catalase, and endothelial NOS as well as a slight increase of p22 phox in HAEC in term of both protein and mRNA expression, suggesting that increased formation of reactive oxygen species such as O2- and OH radical participate in the deterioration for the function of vascular endothelial cells in diabetic patients.

Localization of oxidized HDL in atheromatous plaques and oxidized HDL binding sites on human aortic endothelial cells

We examined the localization of oxidized high-density lipoprotein (HDL) in atheromatous plaques and the oxidized HDL binding sites on endothelial cells. Histochemical analysis using CuSO4-oxidized HDL-specific 9F5-3a antibody indicated the presence of oxidized HDL in the intima of atheromatous plaques in human abdominal aortae. The cell surface binding of 125I-oxidized HDL to cultured human aortic endothelial cells (HAEC) was saturable, with an apparent dissociation constant (Kd) of 1.43 micromol/L. Competition for 125I-oxidized HDL binding was strong for oxidized HDL, moderate for native HDL and low for acetylated low-density lipoprotein (LDL) or oxidized LDL. Using oxidized HDL as a ligand for blotting, a major 130-kDa band was detected in HAEC. These results suggest that oxidized HDL and its putative binding protein are present in atheromatous plaques and endothelial cells, respectively.

Specific gel electrophoresis method detects two isoforms of human intestinal alkaline phosphatase

We have demonstrated that the 6.0% polyacrylamide disc gel electrophoresis (PAGE) method in the presence of 1% Triton X-100 clearly separated both normal molecular mass intestinal alkaline phosphatase (NIAP) and bone alkaline phosphatase (BAP) in serum regardless of the ABO blood group and the secretor status of the subjects. From the results under the usual 7.5% PAGE condition, overlapping mobilities of NIAP and BAP were found in particular in nonsecretor subjects after a high-fat meal. Under the above conditions, the apparent BAP percentage three hours after a meal was higher in nonsecretors than in subjects under fasting conditions, because NIAP activity in serum rose sharply following a high-fat meal. In contrast, under our 6.0% PAGE method, the NIAP and BAP were clearly separated from each other regardless of whether the subjects were fasting or had ingested a high-fat meal. In addition, an elevated level of the circulating NIAP can be another marker for patients with liver cirrhosis. Considering all these factors, the 6.0% PAGE method proposed by us is not only a useful method for the separation of intestinal alkaline phosphatase (IAP) isoforms, but can also be useful for the analysis of other usual AP isozymes.

Reactive oxygen species as a risk factor in verotoxin-1-exposed rats

It has been suggested the the interaction of Escherichia coli O157-derived verotoxins (VTs) with the vascular endothelium plays a central role in the pathogenesis of the thrombotic microangiopathy and ischemic lesions characteristic of hemolytic uremic syndrome (HUS) and E. coli O157-associated hemorrhagic colitis. Intravenous administration of both E. coli O157-derived VT1 and lipopolysaccharide (LPS) in the rat induced a synergistic increase in thiobarbituric acid (TBA) values in those animal's plasma, as compared with that injected with VT1 or LPS alone. We then hypothesized that an increase in lipid peroxidation in the rat plasma was due to an enhanced production of endothelial cell-derived reactive oxidant. Based on determination of rat sera and cultured human aortic endothelial cells (HAECs), VT1 had little if any effect on LPS-stimulated increase of nitric oxide and the resultant peroxynitrite generations. Both RT-PCR and Western blot studies of reactive oxygen species-related enzymes showed that VT1 markedly decreased the expression of catalase mRNA and protein in HAECs, but caused less alteration in the levels of Cu, Zn-superoxide dismutase, and NADPH oxidase mRNA. Further studies by spin trapping analysis using 5, 5-dimethyl-1-pyrroline-N-oxide (DMPO) revealed a time-dependent increase in hydroxyl radicals by VT1 in HAECs. The accumulated data thus suggest that bacterial VT1 reduces mainly catalase levels in endothelial cells, which is synergistically potentiated by LPS, and that the resulting hydroxyl radical participates in endothelium injury through a marked enhancement of lipid peroxidation, leading to HUS.

[Detection of anti-Chlamydia trachomatis antibody by means of enzyme immunoassay using synthetic peptide antigen]

Newly developed diagnostic kits for the detection of Anti-Chlamydia trachomatis, Peptide-Chlamvdia (LOY: Meiji Milk Products Co., Ltd., Tokyo; for IgG and IgA), were evaluated using the microimmunofluorescence assay (MIF) as the gold standard. These results were also compared to results of testing by Sero-IPALISA and immunoblot (I-B). Detection by LOY in based on enzyme immunoassay with synthetic peptides as the antigen. Thirty serum samples from pediatric patients and 130 serum samples from gynecology patients were used. All 26 pediatric samples that were positive for Chlamydia pneumoniae IgG antibody tested negative with LOY, indicating that the presence of the antibody against C. pneumoniae did not affect the assay by LOY. For 90 gynecological samples, the total, the positive and the negative agreement rates for IgG were quite high; i.e. 87.8%, 90.0% and 70.0% (LOY vs MIF), 85.6%, 85.0% and 90.0% (Sero-IPALISA vs MIF), and 92.0%, 94.9% and 70.0% (I-B vs MIF), respectively. On the other hand, many cases of MIF (-) and LOY (+) discrepancy were seen in IgA detection. In order to better understand the basis for such disagreement. 34 serum samples were collected from patients whose cervical samples were negative for the Chlamydia group antigen based on the assay with IDEIA-Chlamydia. They were then assayed by MIF and LOY. The total, the positive and the negative agreement rates for IgG were 91.2%, 100% and 90.9%, while the total and the negative agreement rates for IgA were 88.2% and 88.2% (there were no IgA positive cases). Furthermore, 6 serum samples (1 case of MIF (+) LOY (+) and 5 cases of MIF (-) LOY (+)) were provided to determine whether LOY detects C. trachomatis specific IgA antibody. Increasing amounts of C. trachomatis serovar L2 were added to the serum samples resulting in a progressive decrease in their reactivity in the LOY assay. These results lead us to speculate that LOY can reveal even low levels of C. trachomatis specific IgA antibody. In conclusion, LOY can be used as an useful kit for detecting C. trachomatis antibody.

[Expression of reactive oxygen-related enzymes in human umbilical vein endothelial cells (HUVEC) cultured with high concentrations of glucose]

We examined the levels of reactive oxygen-related enzymes in human umbilical vein endothelial cells cultured with high concentrations of glucose, in vitro. From the results, elevated levels of catalase mRNA and its protein were exhibited in the presence of higher glucose. In addition, the message level of p22-phox as the active center of NADPH oxidase, was slightly increased. Taken together, the endothelial injury induced by diabetes may associated to the elevated level of O2- production. However, the level of catalase as .OH scavenger was mainly increased, cooperatively.

[Changes in nitric oxide-related compounds in endotoxemic rats]

NO-related compounds in the blood of septic rats were examined by chemiluminescence method. Rats were treated with 5 mg/kg or 10 mg/kg lipopolysaccharides (LPS) and followed for 30 h. We have determined and evaluated the concentrations of the total NO-related compounds in whole blood (Total-NO), those in plasma (Plasma-NO) and membrane bound-NO (Membranous-NO) in erythrocytes from the LPS-challenged rats. 1) Levels of Plasma-NO after 3 h and Membranous-NO after 7 h in the rats were significantly increased, peaked at 14 h, and then restored to control levels at 30 h. 2) At 7 h in the rats, latter NO levels were exhibited within 10 nM/mg protein. 3) The existence of Membranous-NO can be confirmed by the in vitro experiments of rat erythrocytes incubating with different NO-donors, NOC-3 or SIN-1. 4) Taken together, the determination of Membranous-NO may be an additional marker for pathophysiological states of septic stress.

[Small increases of the serum alkaline phosphatase activity and malignant changes]

In order to see the clinico-pathological significance of the small increase of serum alkaline phosphatase (ALP) activity alone in routine laboratory examinations, we picked up 76 new out-patients of adult within the two-fold high ALP level in contrast to the reference range in the Akita University Hospital for one year, and then studied the relation between the histories and serum ALPs of 33 patients whose ALP had increased pathologically or decreased after intervention such as surgical operations. The ratio of the patients with malignant tumors to the tested all patients was 13 to 76 (17%). Immunochemical analysis of sera for the cancers of the lung, larynx and prostate showed that the small amount of the placental isozyme or intestinal-like isozyme was expressed selectively. It may be useful for earlier detection of malignancy to analyze the cancer-associated ALPs, when the small and sequential increase of the serum ALP activity is found in routine laboratory examinations.

Reduced alkaline phosphatase activity in diabetic rat bone: a re-evaluation

We found previously that human bone alkaline phosphatase (AP) was glycated by aseptic incubation with glucose, and partially broken down by reactive oxygen species. In this study, we examined whether selective in vivo glycation of AP molecules occurred in bone tissue, using experimental diabetic rats induced by streptozotocin and spontaneously diabetic rats. Additionally, the effects of hyperlipidemia on bone AP activity were examined. Serum AP activity was significantly elevated after incipient onset of diabetes, and the increased activity originated from the intestinal isozyme. High levels of intestinal AP activity were also observed in rats with hyperlipidemia induced by feeding high-fat or high-fructose chow, but the AP activity in bone tissues was maintained at a constant level. AP activity in bone was reduced after the onset of diabetes. The resulting bone AP molecule bound to an aminophenylboronic acid column, which had affinity for glycated proteins, and contained smaller molecular sizes than the native bone AP. These results suggest that elevated levels of serum AP activity originated from the intestinal isozyme accompanied with hyperlipidemia induced by diabetes. In contrast, the reduced serum levels of AP activity in diabetic rats might be dependent on inactivation of bone AP, which was glycated, followed by partial breakdown of bone AP molecules, possibly due to reactive oxygen species.

Changes in intestinal alkaline phosphatase isoforms in healthy subjects bearing the blood group secretor and non-secretor

We found the high molecular mass intestinal alkaline phosphatase (HIAP) and normal molecular mass intestinal alkaline phosphatase (NIAP) in serum at fasting and after fatty meal by use of 6.0% polyacrylamide gel electrophoresis (PAGE) in the presence of 1% Triton X-100. HIAP only appeared in serum of Lewis blood group secretors ¿Le(a-b+)¿, and HIAP levels were dependent on ABO blood groups. Among the secretors, the highest activities of HIAP in fasting serum were observed in subjects with blood groups O and B (8.6+/-1.4 U/1; mean+/-SD) and the lowest activities were associated with blood group A (0.7+/-0.2 U/1; mean+/-SD), and the HIAP activities did not change after fatty meal. In contrast, NIAP was present in the serum of both secretors and non-secretors regardless of ABO blood group. Trace amounts of NIAP remained in fasting serum; however serum NIAP activities rose sharply after fatty meal. The remaining ratios of NIAP activity at fasting and 9 h after fatty meal of secretors were approximately the same as those of non-secretors. The electrophoretic mobility on PAGE or the apparent molecular mass estimated by gel filtration of serum NIAP in secretors was slightly different from that in non-secretors. In addition, HIAP can be normalized to NIAP on PAGE in the absence of Triton X-100, and the electrophoretic mobility of normalized-NIAP was identical to that of original NIAP in secretors. Accordingly, it can be concluded that the structure of serum NIAP in the secretor was different from that in the non-secretor, because HIAP is only formed by serum NIAP in the secretor. These results suggest that differences in serum NIAP in the secretor and the non-secretor may be closely related to the appearance of IAP in the circulation.

Partial breakdown of glycated alkaline phosphatases mediated by reactive oxygen species

The lower levels of serum alkaline phosphatase (AP) activity found in patients with diabetes mellitus apparently originate from the selective disappearance or decrease in bone AP activity in the circulation. Hence, we investigated in vitro the effect of glycation on the activities of five AP isozymes. Aseptic incubation with 25 mmol/L of D-glucose and APs rapidly reduced bone and placental AP activities before those of liver, kidney and intestinal enzymes. The resulting bone and placental AP molecules were clearly glycated, according to the result of aminophenylboronic acid affinity chromatography. Furthermore, Western blotting analysis revealed that the placental AP molecule was fragmented, and its partial cleavage took place at Ala154 on the AP molecule. Since glycation of serum proteins causes the generation of reactive oxygen species, the effects of reactive oxygen species on placental AP activity were assayed, and the results indicated that hydroxyl radicals might be a major factor for the specific inactivation of AP activities. The reduction in AP activity by incubation with glucose in vitro was reversed by the further addition of catalase. Furthermore, ferrous ion with hydrogen peroxide, which generates hydroxyl radicals, had an inhibitory effect on AP activities. These findings suggest that the reduced AP activity in diabetic patients might result from partial cleavage of the bone AP molecule by reactive oxygen species induced by glycation.

Properties of high-molecular-mass placental alkaline phosphatases in normal pregnancy sera

We examined the appearance of high-molecular-mass placental alkaline phosphatases (HPLAPs) in the serum of normal pregnant women by means of polyacrylamide gel electrophoresis (PAGE) in the presence of Triton X-100. The HPLAPs were undetectable or only slightly detectable by PAGE in the absence of Triton X-100. The HPLAPs were detected in all sera sampled during the last trimester of pregnancy. The catalytic activities of total placental alkaline phosphatase (TPLAP) and HPLAPs were correlated (r = 0.96) and the ratio of HPLAPs/TPLAP catalytic activity was 0.20 (0.06) (mean and SD) in 40 serum samples from pregnant women. The HPLAPs appear to be formed from a common dimeric placental alkaline phosphatase (PLAP) (common-PLAP), as judged by the fact that they were formed again after removal of HPLAPs from serum by gel filtration. The formation of HPLAPs was more prominently observed with the faster fractions of gel filtration. The apparent molecular mass of the HPLAPs in pregnancy serum was 720 KDa by gel filtration. HPLAPs were not converted to common-PLAP by phosphatidylinositol-specific phospholipase (PIPL) C and PIPL-D treatments. The HPLAPs were selectively incorporated into liposomes consisting of phosphatidylcholine/cholesterol, and most of the PIPL-D-treated PLAP could from HPLAPs, while a small amount of PLAP could not form HPLAPs. On the other hand, HPLAPs in pregnant women's sera and HPLAPs prepared from partially purified PLAP in vitro could be converted to common-PLAP by brief treatment with subtilisin. However, the highly purified PLAP could not form HPLAPs in the presence of Triton X-100. These results suggest that PIPL-D-resistant and PLAP-associated serum protein may regulate the conversion of PLAP to HPLAP in the presence of Triton X-100.