Biomedical subjects

Itaru Furuta

Publications and source records attributed to Itaru Furuta.

7 recordsLinked to original sources

PubMed2003

A new fungal lectin recognizing alpha(1-6)-linked fucose in the N-glycan.

In this report, we describe a new lectin from the fungus Rhizopus stolonifer that agglutinates rabbit red blood cells. Agglutinating activity was detected in the extract of mycelium-forming spores cultured on agar plates but not in the mycelium-forming no spores from liquid medium. This lectin, which we designated R. stolonifer lectin (RSL), was isolated by affinity chromatography with porcine stomach mucin-Sepharose. SDS-polyacrylamide gel electrophoresis and mass spectral analysis showed that RSL is approximately 4.5 kDa, whereas gel filtration indicated a mass of 28 kDa. This indicates that the lectin is a hexamer of noncovalently associated RSL monomers. RSL activity was very stable, since it was insensitive to heat treatment at 70 degrees C for 10 min. Analysis of RSL binding specificity by both microtiter plate and precipitation assays showed that N-glycans with l-fucose linked to the reducing terminal GlcNAc residues are the most potent inhibitors of RSL binding, whereas N-glycans without alpha(1-6)-linked fucose residues are approximately 100-fold weaker inhibitors of binding. Oligosaccharides with alpha(1-2, -3, and -4) linkages showed no inhibition of binding in these assays. In a mirror resonance biosensor assay, high affinity binding was observed between RSL and the glycopeptide of bovine gamma-globulin, which has N-glycans with alpha(1-6)-linked fucose residues. However, RSL showed only a weak interaction with the glycopeptide of quail ovomucoid, which lacks fucose residues. Finally, capillary affinity electrophoresis studies indicated that RSL binds strongly to N-glycans with alpha(1-6)-linked fucose residues. Together, these results show that RSL recognizes the core structure of N-glycans with alpha(1-6)-linked l-fucose residues. This specificity could make RSL a valuable tool for glycobiological studies.

Amino Acid Sequence↗

PubMed2003

A new type of temperature-dependent serum M protein: a case of IgG-lambda type multiple myeloma.

BACKGROUND: We report a rare case of temperature-dependent serum M protein (thermoprotein), monoclonal IgG(1)-lambda protein isolated from 90-year-old female with advanced multiple myeloma. METHODS: M protein was identified in the blood plasma of the patient by immunoelectrophoresis (IEP). To evaluate the types of bonds, the properties of the protein after reduction and chemical treatment were examined. RESULTS: This protein was irreversibly precipitated at or above room temperature when exposed in the air. This protein was redissolved by 30 mmol/l dithiothreitol, 4 mol/l urea, or 8 mmol/l EDTA. CONCLUSIONS: Unlike other immunoglobulins reported to date, this data suggests that hydrogen, disulfide, and ionic bonds are involved in the temperature-dependent precipitation of this M protein.

Aged↗

PubMed2003

Determination of antibacterial flomoxef in serum by capillary electrophoresis.

A determination method of flomoxef (FMOX) concentration in serum by capillary electrophoresis is developed. Serum samples are extracted with acetonitrile. After pretreatment, they are separated in a fused-silica capillary tube with a 25 mM borate buffer (pH 10.0) as a running buffer that contains 50mM sodium dodecyl sulfate. The FMOX and acetaminophen (internal standard) are detected by UV absorbance at 200 nm. Linearity (0-200 mg/L) is good, and the minimum limit of detection is 1.0 mg/L (S/N = 3). The relative standard deviations of intra- and interassay variability are 1.60-4.78% and 2.10-3.31%, respectively, and the recovery rate is 84-98%. This method can be used for determination of FMOX concentration in serum.

Cephalosporins↗

PubMed2002

Method development for determining the antibacterial linezolid in human serum by micellar electrokinetic capillary chromatography.

A precise method for determining linezolid concentration in human serum by micellar electrokinetic capillary chromatography has been developed and validated. Serum was deproteinized with acetonitrile and etofylline was used as an internal standard. A borate buffer (pH 10.0; 25 mM) containing sodium dodecyl sulfate (80 mM) was used as a running buffer. Detection was performed at UV253 nm by applying 25 kV voltage to a fused-silica capillary tube. Migration time of linezolid was approximately 14 min. Good linearity (0-100 mg/l) was obtained and the limit of detection was 0.5 mg/l (S/N=3). This technique covered the clinical concentration (4 mg/l) measurement of this drug enough. The intra- and inter-day reproducibility was good. Serum recovery was 95-102%. No interference from other anti-microbial agents was observed. Linezolid after serum deproteinization showed high stability. This method was easy to operate as well as economical as a method for determining linezolid in serum.

Acetamides↗

PubMed2002

Quantification of pilsicainide in serum by capillary electrophoresis.

A new method for determining pilsicainide concentration in serum by rapid and selective capillary electrophoresis has been developed and validated. For pretreatment, serum was made alkaline and then extracted with diethyl ether. Procainamide was used as an internal standard. Sodium dihydrogenphosphate buffer (pH 2.29; 0.1 M) was used as a running buffer. A fused-silica capillary tube was loaded with a voltage of 25 kV and detection was performed at UV 200 nm. Good linearity (0-2.5 microg/ml) was obtained with the minimum limit of detection being 0.04 microg/ml serum (signal-to-noise ratio, 3:1). The R.S.D. of within-run reproducibility was 0.798-2.32%, that of between-run reproducibility was 4.74-5.12% and the recovery rate was 61-63%. Disopyramide, another anti-arrhythmic drug, was close to pilsicainide in terms of migration time. This method was applied to determination of pilsicainide in serum samples.

Anti-Arrhythmia Agents↗

PubMed2002

[Mycoses].

Antifungal susceptibility testing has developed rapidly during the last decade. Through the intensive collaborative work, the National Committee for Clinical Laboratory Standards (NCCLS) has published a standardized antifungal susceptibility method M27-A which included interpretive guidelines for 3 antifungal agents. Meaningful large-scale, longitudinal studies of antifungal susceptibility and resistance, based on standardized methodology and interpretive guidelines, have been published and serve as the basis for analysis of resistance trends. Resistant isolates have been further characterized using molecular biological techniques. Candida albicans and related species become resistant to antifungal agents, in particular triazoles, by expression of efflux pomps that reduce drug accumulation, alteration of the structure or concentration of antifungal target enzymes, and alteration of membrane sterol composition. On the other hand, there are several ongoing problems in antifungal susceptibility testing such as trailing phenomenon, ability to detect amphotericin B resistance, and application for other fungal pathogens. In this paper, we review studies which focused on the reliability of antifungal susceptibility testing, epidemiology of resistant isolates, and resistant mechanisms. Furthermore, we provide several recommendations for antifungal susceptibility testing in the clinical laboratory.

Antifungal Agents↗

PubMed2002

[Diagnosed tuberculosis using specific DNA probe hybridization methods].

In Japan, reported cases of tuberculosis had declined nearly every year until 1995. However, in 1997 newly recorded cases began increasing for the first time in more than 38 years. Recent studies using DNA fingerprinting show that person- to person transmission may account for as many as one-third of new cases of tuberculosis in citizen populations. Nucleic acid hybridization methods using specific DNA probes can specifically identify M. tuberculosis and other mycobacterial species. Rapid nucleic acid amplification techniques such as polymerase chain reaction methods allow direct identification of M. tuberculosis in clinical specimens. Is 6110 has been exploited extensively as a clonal marker in molecular epidemiology studies of tuberculosis. The emergence of resistance to antituberculosis drugs is a relevant matter worldwide. A recent genotypic method allows earlier detection of RFP-resistant and INH-resistant stains using probes for mutation in rpoB and in katG.

Bacterial Proteins↗