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Biomedical subjects

T Adachi

Publications and source records attributed to T Adachi.

At least 325 records · Page 18Linked to original sources

[Measurement of serum and sputum eosinophil cationic protein concentrations in asthma].

Concentrations of eosinophil cationic protein (ECP) were measured in serum from patients with asthma, patients with chronic obstructive pulmonary disease (COPD), and healthy subjects. The relationships between serum ECP concentration and percent of predicted FEV1 (%FEV1), and between serum and sputum ECP concentrations were also examined in patients with asthma. Serum ECP concentration in asthma was significantly higher than those in COPD patients and healthy subjects. There was a significant inverse correlation between serum ECP concentration and %FEV1 when analysis was restricted to data from asthma patients less than 60 years old. ECP concentration in serum and in sputum were significantly correlated. These results suggest that in asthma patients, eosinophils are activated in serum, and that the degree of eosinophil activation in the airway can be estimated by measuring serum ECP to some extent. Because it does not require bronchial biopsy or bronchoalveolar lavage, measurement of serum ECP may be useful as a minimally invasive monitoring of asthma.

Adult↗

Seasonal differences in diurnal blood pressure of hypertensive patients living in a stable environmental temperature.

OBJECTIVE: To determine whether there is a seasonal variation in blood pressure in hypertensive patients whose daily lifestyle is similar in summer and in winter, and who live almost entirely indoors in a stable environmental temperature. SUBJECTS AND METHODS: During summer and winter, blood pressure was measured by ambulatory blood pressure monitoring in outpatients with essential hypertension, and environmental temperature was measured by electrothermometer while the patients were awake. The 24-h blood pressure data were analysed after being divided into four groups: morning, afternoon, night-time and sleeping periods. RESULTS: We studied 25 outpatients (mean +/- SD age 57 +/- 12 years) who spend virtually the entire day indoors in both summer and winter. Measurements of systolic and diastolic blood pressure in the morning and night-time periods were significantly higher in winter than in summer (differences of 7.5 +/- 14.7 and 4.1 +/- 8.8 mmHg and 8.2 +/- 14.8 and 4.5 +/- 8.1 mmHg, respectively). Blood pressure measured in the afternoon and during sleeping periods did not differ significantly. No correlation was observed between the seasonal change in blood pressure in the morning and that at night. Environmental temperatures were significantly higher in the morning, afternoon and night-time periods during summer than those during winter. The differences among these periods were not statistically significant. CONCLUSIONS: There is a seasonal variation in blood pressure in the morning and night-time periods during winter in hypertensive patients who live essentially indoors in a relatively stable environmental temperature. Pressor factor(s) may differ between morning and night-time periods during winter.

Activity Cycles↗

Involvement of L-tryptophan aminotransferase in indole-3-acetic acid biosynthesis in Enterobacter cloacae.

L-Tryptophan aminotransferase (L-tryptophan:2-oxoglutarate aminotransferase; EC 2.6.1.27) from Enterobacter cloacae was purified 62-fold and characterized to determine its role in indole-3-acetic acid biosynthesis. The enzyme reversibly catalyzed the transamination of L-tryptophan with 2-oxoglutarate as the amino acceptor to yield indole-3-pyruvic acid and L-glutamate, and the Km values for L-tryptophan and indole-3-pyruvic acid were 3.3 mM and 24 microM, respectively. In the indole-3-acetaldehyde synthesis experiments in vitro, 94% of L-tryptophan was efficiently converted to indole-3-acetaldehyde by the purified L-tryptophan aminotransferase plus indolepyruvate decarboxylase. Furthermore, the amounts of L-tryptophan decreased with increases in the indolepyruvate decarboxylase activity, while the amounts of indole-3-acetaldehyde increased with increases in this activity. In genetic experiments, the amounts of L-tryptophan produced by Enterobacter and Pseudomonas strains harboring the gene for indolepyruvate decarboxylase were lower than those produced by these same strains without the gene, while the amounts of indole-3-acetic acid produced by Enterobacter and Pseudomonas strains harboring the gene for indolepyruvate decarboxylase were higher than those produced by these same strains without the gene. These results clearly show that L-tryptophan aminotransferase is involved in the indole-3-acetic acid biosynthesis and that indolepyruvate decarboxylase is the rate-limiting step in this pathway.

Carboxy-Lyases↗

The alkaline phosphatase in human plexus chorioideus.

The content of alkaline phosphatase isozymes in various brain regions was determined by monoclonal immunocatalytic assays. The levels of the isozymes in human brain tissues were low compared with those in other human tissues, liver, kidney, bone, intestine and placenta. Plexus chorioideus in the brain, however, was found to express significant amounts of alkaline phosphatase activity. The purified isozyme from human plexus chorioideus demonstrated a single 70 kDa protein band on SDS-polyacrylamide gel which coincides with that of tissue-unspecific alkaline phosphatase from human liver. The isozyme expressed in the plexus was confirmed to be the tissue-unspecific alkaline phosphatase isozyme with regard to its reactivity with monoclonal antibodies specific for liver alkaline phosphatase, heat stability, and the inhibition by amino acids. This finding adds new dimensions to the functional role this isozyme may play.

Alkaline Phosphatase↗

Influence of dietary levels of protein and sulfur amino acids on the fate of methylmercury in mice.

We previously reported that the fate of methylmercury (MeHg) in mice was affected by dietary protein levels. To study the mechanism of this alteration, we investigated the effect of sulfur amino acid supplement for a lowered protein diet on the fate of MeHg. C57BL/6N male mice were fed on a 24.8% protein diet (normal protein diet, NPD), a 7.5% protein diet (low protein diet, LPD), or LPD supplemented by methionine and cystine so as maintain the normal levels (amino acid supplemented diet, ASD) for 5 days. NPD-fed mice were used as controls. The mice were orally administered MeHg chloride (20 mumol/kg), and were examined after 24 h distribution and excretion of Hg. The Hg level in brain increased with LPD feeding and was further enhanced by ASD feeding. The hepatic Hg level increased only with ASD feeding. Although Hg levels in kidney, blood and plasma did not change with LPD feeding, these decreased with ASD feeding. The urinary Hg level that decreased with LPD feeding was recovered and exceeded by far the control levels with ASD feeding. When mice were intravenously injected with MeHg-bovine serum albumin, the Hg uptake rate in the brain increased in LPD-fed mice and was further enhanced in ASD-fed mice. The brain uptake of intravenously injected L-[14C]phenylalanine was also accelerated with LPD or ASD feeding, which indicated that LPD or ASD feeding increased activity of neutral amino acid transport in the brain. This would cause increased Hg uptake in the brain, since MeHg reaches the brain through this transport system. Hg ratio in plasma low molecular weight fraction increased in ASD-fed mice, but not in LPD-fed mice. This might contribute to the further enhanced Hg uptake in the brain with ASD feeding. Analysis of thiol compounds in plasma and urine revealed increased levels with ASD feeding. The present results suggest that insufficiency of sulfur amino acids in LPD is one reason for the alteration in the fate of MeHg induced by LPD feeding. It is also suggested that the change in neutral amino acid transport caused by LPD feeding is involved in the alteration in the fate of MeHg.

Animals↗

Cloning and nucleotide sequence of a bacterial cytochrome P-450VD25 gene encoding vitamin D-3 25-hydroxylase.

The gene encoding an enzyme that catalyzes the hydroxylation at position 25 of vitamin D-3 was cloned from an actinomycete strain, Amycolata autotrophica, by use of a host-vector system of Streptomyces lividans. The amino acid sequence deduced from the nucleotide sequence revealed that this enzyme, tentatively named P-450VD25, contains several regions of strong similarity with amino acid sequences of cytochromes P-450 from a variety of organisms, primarily in the regions of an oxygen-binding site and a heme ligand pocket. Especially, P-450VD25 shows end-to-end similarity in amino acid sequence to P-450dNIR of Fusarium oxysporum and P-450SU2 of Streptomyces griseolus. The recombinant S. lividans strain containing the P-450VD25 gene on a multicopy plasmid converted vitamin D-3 in the medium into 25-hydroxyvitamin D-3 at a maximum yield of 10%.

Actinomycetales↗

The IgM antigen receptor of B lymphocytes is associated with prohibitin and a prohibitin-related protein.

The two major classes of antigen receptors on murine B lymphocytes, mIgM and mIgD, are both contained in a complex with two additional molecules, Ig-alpha and Ig-beta, which permit signal transduction. Accordingly, early biochemical events after antigen binding to either receptor are similar; biological effects, however, are different. Here, we describe three newly discovered intracellular proteins of 32, 37 and 41 kDa molecular mass, that are non-covalently associated with mIgM, but not with mIgD. These proteins coprecipitate with mIgM in Triton X-100 and Nonidet P-40, but not in digitonin lysates. In addition, mIgM is to some extent associated with 29 and 31 kDa proteins that are predominantly associated with mIgD (see accompanying paper). Amino acid sequencing of p32 and p37 identified p32 as mouse prohibitin; this was corroborated by Western blot analysis with antibodies specific for rat prohibitin. p37 is a newly discovered protein. cDNA clones for both proteins were isolated and sequenced. The deduced amino acid sequence of p32 is identical to that of rat prohibitin. p37 is highly homologous to p32. Since prohibitin was identified as an inhibitor of cell proliferation, its association with mIgM, but not mIgD, could explain the different biological events elicited after engagement of each receptor.

Amino Acid Sequence↗

Two new proteins preferentially associated with membrane immunoglobulin D.

The IgM and IgD classes of antigen receptor can perform different functions on B cells. However, so far no class-specific components communicating with the cytoplasm have been found in the two antigen receptors. We have employed a new biotinylation protocol to search for intracellular membrane Ig-associated proteins. Here we describe two proteins of 29 and 31 kDa that are associated with membrane IgD and to some extent with membrane IgM. The membrane IgM molecule is associated specifically with three proteins of 32, 37 and 41 kDa. The purification and sequencing of the two mIgD-associated proteins revealed that they are novel proteins which are related to each other. These proteins may be the missing link between the antigen receptor and the cytoskeleton and may contribute to functional differences between membrane IgM and membrane IgD.

Amino Acid Sequence↗

Expression of a heterodimeric (placental-intestinal) hybrid alkaline phosphatase in KB cells.

A hybrid heterodimeric alkaline phosphatase expressed in KB cells, consisting of placental and intestinal (fetal) subunits, was purified by use of two different immunoaffinity columns using the monoclonal antibodies 2HIMS-1 and HPMS-1. The closely related subunits were found to yield a dimeric active enzyme glycosylated as the mature heterodimeric forms. This enzyme displays intermediate properties to the placental and intestinal (fetal) isozymes with regard to heat stability, inhibition patterns with amino acids and amino acid derivatives, as well as reactivity with monoclonal antibodies specific for human alkaline phosphatase isozymes. Peptide fragments obtained from the hybrid enzyme after cyanogen bromide cleavage belong to either the placental or intestinal (meconial) isozyme as evaluated by SDS polyacrylamid gel electrophoresis, and the N-terminal amino acid sequences, corresponding to the placental and intestinal subunits, can be identified in the peptide fragments. By N-glycanase digestion or tunicamycin treatment, the molecular mass of the subunits was reduced to 62 kDa compared to 69 kDa for the native ones. The results confirm that some cell lines can synthesize hybrid alkaline phosphatases.

Alkaline Phosphatase↗

Isolation and characterization of alginate-derived oligosaccharides with root growth-promoting activities.

Lytic digestion of poly(mannuronate), poly(guluronate), and alginate with an alginate lyase from Alteromonas macleodii was used to prepare mixtures of unsaturated oligosaccharides. Four oligosaccharides isolated from the alginate lyase-lysate by anion-exchange chromatography on Q-Sepharose were found to be the major components of the root growth-promoting lysate. The oligosaccharides were analyzed by NMR and SIMS and identified as di- and tri-saccharides having O-(4-deoxy-L-erythro-hex-4-enopyranosyluronic acid)-1--> at the nonreducing terminus. The trisaccharides from the lysate were found to have root growth-promoting activity in a barley bioassay.

Alginates↗

Production and characterization of monoclonal antibodies directed against bovine milk fat globule membrane (MFGM).

Nine hybridomas secreting monoclonal antibodies (mAbs) to bovine milk fat globule membrane (MFGM) were produced from spleen cells of three immunized BALB/c mice. Several MFGM antigens recognized by some mAbs were identified as a 120 kDa protein and 67 kDa (butyrophilin), 57 kDa (PAS-6), 53 kDa (PAS-7), 33 kDa glycoproteins. The other mAbs secreted by four independent hybridoma clones recognized many broad bands ranging from 20 to 200 kDa. The 120 kDa protein and 67 kDa, 57 kDa, 53 kDa glycoproteins were detected by each mAb in the plasma membrane fraction prepared from a lactating bovine mammary gland. Moreover, mammary gland epithelium of a thin section was specifically stained with these mAbs, indicating that these mAbs directed against MFGM recognized membrane proteins and glycoproteins of lactating mammary epithelial cells. Upon heating of the MFGM in phosphate buffer, pH 7.4 at 100 degrees C for 10 min, the antigens still retained most of its reactivity to these mAbs, whereas, proteolytic cleavage by trypsin and chymotrypsin strongly reduced its reactivity to these mAbs by 60% or more except for two mAbs which recognized the 57 and 53 kDa glycoproteins, respectively.

Animals↗

Functional communication in the recognition of tRNA by Escherichia coli glutaminyl-tRNA synthetase.

Wild-type Escherichia coli glutaminyl-tRNA synthetase (GlnRS; EC 6.1.1.18) poorly aminoacylates opal suppressors (GLN) derived from tRNA(Gln). Mutations in glnS (the gene encoding GlnRS) that compensate for impaired aminoacylation were isolated by genetic selection. Two glnS mutants were obtained by using opal suppressors differing in the nucleotides composing the base pair at 3.70: glnS113 with an Asp-235-->Asn change selected with GLNA3U70 (GLN carrying G3-->A and C70-->U changes), and glnS114 with a Gln-318-->Arg change selected with GLNU70 (GLN carrying a C70-->U change). The Asp-235-->Asn change was identified previously by genetic selection. Additional mutants were isolated by site-directed mutagenesis followed by genetic selection; the mutant enzymes have single amino acid changes (Lys-317-->Arg and Gln-318-->Lys). A number of mutants with no phenotype also were obtained randomly. In vitro aminoacylation of a tRNA(Gln) transcript by GlnRS enzymes with Lys-317-->Arg, Gln-318-->Lys, or Gln-318-->Arg changes shows that the enzyme's kinetic parameters are not greatly affected by the mutations. However, aminoacylation of a tRNA(Gln) transcript with an opal (UCA) anticodon shows that the specificity constants (kcat/Km) for the mutant enzymes were 5-10 times above that of the wild-type GlnRS. Interactions between Lys-317 and Gln-318 with the inside of the L-shaped tRNA and with the side chain of Gln-234 provide a connection between the acceptor end-binding and anticodon-binding domains of GlnRS. The GlnRS mutants isolated suggest that perturbation of the interactions with the inside of the tRNA L shape results in relaxed anticodon recognition.

Amino Acid Sequence↗

Fracture of the tibial tray following PCA knee replacement. A report of two cases.

We report two cases in which fracture of the tibial metal tray was thought to be due to improper design of the tray and heavy polyethylene wear. The bone beneath the fractured portion of the tray was deficient and had been replaced by granulomatous fibrous tissue including numerous polyethylene wear particles and foreign-body giant cells. Osteolysis occurred as a tissue reaction to these particles.

Aged↗

Quantitative and qualitative changes of extracellular-superoxide dismutase in patients with various diseases.

Extracellular-superoxide dismutase (EC-SOD) is a secretory glycoprotein that is the major SOD isozyme in extracellular fluids. It has previously been shown that EC-SOD levels in sera from healthy persons are clearly divided into two discontinuous groups: a lower group (named Group I, below 120 ng/ml) and a higher group (Group II, above 400 ng/ml). The family studies have shown that the high EC-SOD level in healthy persons is genetically transmitted. We report here on the EC-SOD levels in the sera of patients with various diseases. The EC-SOD levels were distinctly higher in patients with renal diseases and moderately higher in liver diseases and diabetes than those in normal healthy persons. In cerebrovascular diseases, heart diseases and acute digestive diseases, significant differences of EC-SOD were not observed. In patients with renal diseases, the increase of EC-SOD was accompanied by the lack of renal function. Serum EC-SOD in Group I healthy persons is known to be heterogeneous with regard to heparin affinity and can be separated into three fractions: A without affinity, B with weak affinity and C with relatively strong heparin affinity, whereas the EC-SOD in Group II is mainly one fraction of C-type. Also in the case of hemodialysis patients, serum EC-SOD in Group I or Group I' (approximately 120-400 ng/ml) was divided into three fractions. EC-SOD in Group II showed two different profiles on heparin-Sepharose column chromatographies: one consisted mainly of EC-SOD C and the other consisted of EC-SOD A and C. It is probable that the high serum EC-SOD level in hemodialysis patients was due to two possible factors: the genetic transmitted factor and unknown pathophysiological factor(s).

Cerebrovascular Disorders↗

Effect of successful angioplasty following thrombolysis on infarct size and left ventricular function.

The role of the angioplasty following thrombolysis in acute myocardial infarction has been discussed in several studies, however the effect of successful angioplasty on infarct size and left ventricular function has not been properly evaluated. Successful reperfusion was achieved in 79 out of 104 patients with primary anterior acute myocardial infarction. These patients were classified as follows, according to the type of intervention during the acute phase: 50 patients in which thrombolysis was successful (the thrombolysis group); 12 patients who underwent successful immediate angioplasty following successful thrombolysis (the immediate angioplasty group); and 17 patients in which rescue angioplasty was successful (the rescue angioplasty group). The 25 patients whose infarct-related vessels were not reperfused after intervention were classified as the non-reperfused group. Infarct size, evaluated as defect volume by T1-201 SPECT, 1 month after the onset, was 840 +/- 154 units (mean +/- S.D.) in the immediate angioplasty group and was similar to that in the thrombolysis group (948 +/- 88 units), but significantly smaller than in the non-reperfused group (1759 +/- 108 units). There were no significant differences in left ventricular function in the immediate angioplasty group and the thrombolysis group. Successful rescue angioplasty did not have any beneficial effect on left ventricular functions or infarct size, when compared with the failed thrombolytic group (1105 +/- 169 units vs. 1617 +/- 169 units). End-diastolic volume (52 +/- 3 ml/m2) in the successful rescue angioplasty group, however, was significantly smaller than in the failed thrombolysis group (67 +/- 3 ml/m2).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Relation between endothelin-1 spillover in the lungs and pulmonary vascular resistance in patients with chronic heart failure.

OBJECTIVES: The aim of this study was to clarify the origin of plasma endothelin-1 and to determine the relation between pulmonary vascular resistance and endothelin-1 secretion in the pulmonary circulation in patients with chronic congestive heart failure. BACKGROUND: Plasma levels of endothelin-1, a potent endothelium-derived vasoconstrictor peptide, are increased in congestive heart failure, but the source has not been clarified. Recent studies have indicated a relation between endothelin-1 and pulmonary hypertension. We therefore evaluated the contribution of endothelin-1 secretion in the pulmonary circulation to the regulation of pulmonary vascular resistance in patients with chronic heart failure. METHODS: A comparison was made of the plasma levels of endothelin-1 between the main pulmonary artery and the pulmonary capillary wedge region, as well as between the femoral artery and the femoral vein in 62 patients with chronic heart failure. Stepwise multivariate regression analysis was used to detect independent predictors of pulmonary vascular resistance among the various vasoconstrictor hormones in these patients. RESULTS: There was no significant difference in plasma endothelin-1 levels between the femoral artery and vein. In contrast, plasma endothelin-1 increased significantly from the main pulmonary artery to the pulmonary capillary wedge region ([mean +/- SEM] 3.1 +/- 0.23 vs. 4.6 +/- 0.36 pg/ml, p < 0.01), and the increase was related to the severity of heart failure. Among the various vasoconstrictor factors, such as plasma active renin concentration, plasma angiotensin II, plasma norepinephrine, femoral venous plasma endothelin-1 and pulmonary endothelin-1 spillover, only endothelin-1 spillover in the lungs showed an independent and significant correlation with pulmonary vascular resistance (r = 0.82, p < 0.001). CONCLUSIONS: The main source of circulating endothelin-1 is not the peripheral vascular bed but the pulmonary vascular bed in patients with chronic heart failure. In addition, endothelin-1 secretion in the lungs may regulate the pulmonary vascular resistance in patients with chronic heart failure. These findings are consistent with a significant role for endogenous endothelin-1 in the pathophysiology of heart failure, especially in the pulmonary circulation.

Adult↗

Internalization of human extracellular-superoxide dismutase by bovine aortic endothelial cells.

The high heparin-affinity subtype C of the secretory enzyme extracellular-superoxide dismutase (EC-SOD) mainly exists on the outside of endothelial cell surface in the vasculature. Radioiodinated recombinant EC-SOD C(r-EC-SOD C) bound to cultured bovine aortic endothelial cells (BAE cells) at 4 degrees C with an association constant of 9.35 x 10(6) M-1 and maximum binding of 600 ng/dish (3109 ng/mg cellular protein). When incubated at 37 degrees C for 1 h, some 125I-r-EC-SOD C was no longer releasable by heparin treatment, suggesting that 125I-r-EC-SOD C was internalized by BAE cells. Since the internalization was inhibited in the presence of heparin in medium, this step was mediated by the binding to cell surface heparin sulfate proteoglycans. When cells containing internalized 125I-r-EC-SOD C were incubated in newly added medium at 37 degrees C for up to 1 h, 54% of radioactivity was recovered in new medium. However, 71% of the radioactive materials released to the medium, presumably 125I-r-EC-SOD C and its metabolic products, had lost heparin binding activity. Much of internalized 125I-r-EC-SOD C was degraded to low molecular weight peptides, because 54% of the radioactive products released to the medium were trichloroacetic acid-soluble and 59% of them were below 10 kDa. About one-fourth of radioactive materials were recycled 125I-r-EC-SOD judged from heparin-HPLC and Sephacryl S-200 column chromatography. In the presence of chloroquine, lysosomal protease inhibitor, the release of internalized 125I-r-EC-SOD C decreased to 59% compared with the control culture.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗