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1.
J Radiat Res ; 62(4): 718-725, 2021 Jul 10.
Article in English | MEDLINE | ID: mdl-33912958

ABSTRACT

During radiotherapy sessions to treat brain tumors or head-and-neck cancers, some patients experience unusual visual and/or olfactory perceptions. This prospective study sought to answer two questions: (i) what proportion of patients experience these unpleasant sensations?, and (ii) which organs are responsible? Eligible patients had brain or near-orbital tumors treated by helical tomotherapy. All were aged 10 years or older, able to communicate, and interviewed by a radiation oncologist at least once weekly during radiation therapy. If they had experienced such sensations, they were encouraged to join the second phase of the study. The patients were asked to indicate, using a button, when a sensation commenced and ended. The recorded data were collated with the treatment log. Thirty-eight consecutive patients were eligible. Twenty-six experienced visual and 13 olfactory sensations. The radiation doses to the organs related to the visual or olfactory sensations did not differ between patients who reported sensations and those who did not. Seventeen patients were enrolled in the second phase of the study. All 14 with visual sensations reported that the sensations occurred when the X-rays passed at eye level. Olfactory sensations were reported by eight out of nine patients when the X-rays passed through the olfactory epithelium and/or ethmoid sinus level. In conclusion, 68% of patients experienced visual sensations caused by X-rays passing through the level of the eyes, and 34% complained of olfactory sensations. With the exception of one patient, olfactory sensations occurred when the X-rays passed through the levels of the olfactory epithelium and/or ethmoid sinus.


Subject(s)
Olfactory Perception/physiology , Organ Specificity , Radiotherapy , Visual Perception/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Radiometry , Young Adult
2.
J Stomatol Oral Maxillofac Surg ; 121(5): 589-591, 2020 11.
Article in English | MEDLINE | ID: mdl-32156672

ABSTRACT

Foreign body-induced sialolith is very rare. We report minimally invasive sialendoscopic removal of gold filament thread-induced sialolith in the duct of the parotid gland. A 51-year-old woman with recurrent swelling of the left parotid gland was referred to our hospital. She had undergone insertion of 0.1-mm-diameter gold filament threads into the subdermal skin for facial rejuvenation previously. Computed tomography showed many gold filament threads in the subdermal skin and a sialolith (9.5×4.1×7.9mm) including a gold filament thread in the left parotid duct. The patient underwent endoscopic removal of the sialolith using a 1.6-mm-diameter sialendoscope and Holmium laser under general anesthesia. The sialolith was completely removed with basket and forceps after laser fragmentation, and the broken fragments contained gold filament thread. There was no recurrence of parotid gland swelling after the removal.


Subject(s)
Salivary Gland Calculi , Endoscopy , Female , Gold , Humans , Middle Aged , Parotid Gland , Salivary Ducts/surgery , Salivary Gland Calculi/diagnosis , Salivary Gland Calculi/etiology , Salivary Gland Calculi/surgery
3.
Front Med Biol Eng ; 11(2): 103-15, 2001.
Article in English | MEDLINE | ID: mdl-11575462

ABSTRACT

Changes in the subendo-subepi flow ratio were studied by using a simple electronic circuit model of the coronary vessel consisting of a resistor, capacitor and field effect transistor in order to provide a better understanding of the ischemic vulnerability of the subendocardium. The simulated subendo-subepi flow ratio was found to be approximately 1.2 under normal condition. Changes in the flow ratio were observed while varying the main arterial resistance, mean arterial pressure and intramyocardial pressure individually. The mean flow in the subendocardium was found to decrease at a rate faster than that in the subepicardium with the increase in the septal arterial resistance and the intramyocardial pressure. The same tendency was also observed while the arterial pressure was lowered. This decrease in the mean subendocardial flow is considered to be the effect of higher end-systolic resistance in the subendocardial venule compared to that in the subepicardial venule. These results would be helpful in understanding the vulnerability of the subendocardium to ischemia and in providing clinical treatment to patients with that disease.


Subject(s)
Endocardium/pathology , Endocardium/physiology , Ischemia , Animals , Electronics , Electrophysiology , Humans , Models, Theoretical , Myocardium/metabolism , Pressure , Time Factors
4.
Neurol Res ; 23(5): 435-46, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11474799

ABSTRACT

Artificial neural networks can be exploited to solve inverse problems arising from the estimation of neural activities in the brain. In this paper, we review the network inversion techniques for solving inverse problems with special attention directed towards electroencephalographic dipole localization and the improvement of positron emission tomography. In our regularized network inversion technique, for stabilizing the solution, we explicitly include the a priori knowledge by adding penalty terms to the energy function and/or build this knowledge into the architecture of the multi-layered neural networks that are used as an inverse problem solver. In the electroencephalogram analysis, the consensus term added to the energy function facilitated 3-dipole localization for visually evoked potentials. Effectiveness of our regularization is shown in improving the positron emission tomographic images and for generating metabolic images of the brain, under the constraints given by the a priori knowledge inherent to the measurement systems and physiological rules.


Subject(s)
Algorithms , Brain/metabolism , Electroencephalography/methods , Neural Networks, Computer , Neurophysiology/methods , Signal Processing, Computer-Assisted , Tomography, Emission-Computed/methods , Brain/anatomy & histology , Brain/diagnostic imaging , Humans , Image Processing, Computer-Assisted , Models, Neurological
5.
J Hum Genet ; 46(6): 342-6, 2001.
Article in English | MEDLINE | ID: mdl-11393538

ABSTRACT

The diversity of biological effects resulting from exposure to dioxin may reflect the ability of this environmental pollutant to alter gene expression by binding to the arylhydrocarbon receptor (AHR) gene and related genes. AHR function may be regulated by structural variations in AHR itself, in the AHR repressor (AHRR), in the AHR nuclear translocator (ARNT), or in AHR target molecules such as cytochrome P-4501A1 (CYP1A1) and glutathione S-transferase. Analysis of the genomic organization of AHRR revealed an open reading frame consisting of a 2094-bp mRNA encoded by ten exons. We found one novel polymorphism, a substitution of Ala by Pro at codon 185 (GCC to CCC), in exon 5 of the AHRR gene; among 108 healthy unrelated Japanese women, genotypes Ala/Ala, Ala/Pro, and Pro/Pro were represented, respectively, by 20 (18.5%), 49 (45.4%), and 39 (36.1%) individuals. We did not detect previously published polymorphisms of ARNT (D511N) or the CYP1A1 promoter (G-469A and C-459T) in our subjects, suggesting that these polymorphisms are rare in the Japanese population. No association was found between uterine endometriosis and any polymorphisms in the AHRR, AHR, ARNT, or CYP1A1 genes analyzed in the present study.


Subject(s)
DNA-Binding Proteins , Endometriosis/genetics , Polymorphism, Genetic , Repressor Proteins/genetics , Aryl Hydrocarbon Receptor Nuclear Translocator , Base Sequence , Basic Helix-Loop-Helix Transcription Factors , Case-Control Studies , Cytochrome P-450 CYP1A1/genetics , DNA Primers/genetics , Exons , Female , Humans , Introns , Polymorphism, Single Nucleotide , Receptors, Aryl Hydrocarbon/genetics , Transcription Factors/genetics
6.
Gynecol Oncol ; 81(2): 172-7, 2001 May.
Article in English | MEDLINE | ID: mdl-11330945

ABSTRACT

OBJECTIVE: Little is known about the molecular mechanisms involved in the pathogenesis and/or progression of ovarian cancer (OC). To investigate the genomic imbalances and identify the cancer-related genes associated with this tumor, we applied comparative genomic hybridization (CGH) in OC cell lines. METHODS: Chromosomal aberrations among 17 OC cell lines were analyzed with CGH. Since novel chromosomal regions, including 17q21-23, were identified, we examined the involvement of two candidate genes, PS6K and ZNF147, mapped on this chromosomal region. We examined the status of amplification and expression by fluorescence in situ hybridization as well as by Southern blot analysis and by Northern blot analysis on two candidate genes, respectively. RESULTS: All lines displayed numerous chromosomal imbalances; the most frequent losses were observed on 18q22-23 (29.4%), 13q22-34 (23.5%), 9p (17.6%), 4p11-14 (17.6%), and 11p14-15 (17.6%). The most common gains were noted at 20q12-13 (47.1%), 8q23-24 (35.2%), 5p15 (23.5%), 7q32-36 (23.5%), and 20p (23.5%). High-level gains (HLGs) were detected at 20q12-13 (four cell lines), 8q24 (two cell lines), 12p11-12 (two cell lines), and 17q21-23 (two cell lines). PS6K and ZNF147 genes were amplified in two cell lines exhibiting HLGs at 17q21-23, but not overexpressed. CONCLUSIONS: Our CGH data indicate that OCs have various DNA copy number changes. Among these frequent changes, 17q21-23 may harbor another tumor-associated gene(s) responsible for OC carcinogenesis.


Subject(s)
Chromosomes, Human, Pair 17/genetics , DNA-Binding Proteins/genetics , Ovarian Neoplasms/genetics , Ribosomal Protein S6 Kinases/genetics , Transcription Factors/genetics , Chromosome Aberrations , Female , Gene Amplification , Gene Dosage , Humans , In Situ Hybridization, Fluorescence , Nucleic Acid Hybridization , Ovarian Neoplasms/pathology , Tripartite Motif Proteins , Tumor Cells, Cultured , Ubiquitin-Protein Ligases
8.
Plant Sci ; 158(1-2): 139-145, 2000 Sep 08.
Article in English | MEDLINE | ID: mdl-10996253

ABSTRACT

Carnation petals exhibit autocatalytic ethylene production and wilting during senescence. The autocatalytic ethylene production is caused by the expression of 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase genes, whereas the wilting of petals is related to the expression of the cysteine proteinase (CPase) gene. So far, it has been believed that the ethylene production and wilting are regulated in concert in senescing carnation petals, since the two events occurred closely in parallel with time. In the present study, we investigated the expression of these genes in petals of a transgenic carnation harboring a sense ACC oxidase transgene and in petals of carnation flowers treated with 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS). In petals of the transgenic carnation flowers, treatment with exogenous ethylene caused accumulation of the transcript for CPase and in-rolling (wilting), whereas it caused no or little accumulation of the transcripts for ACC oxidase and ACC synthase and negligible ethylene production. In petals of the flowers treated with DPSS, the transcripts for ACC synthase and ACC oxidase were accumulated, but no significant change in the level of the transcript for CPase was observed. These results suggest that the expression of ACC synthase and ACC oxidase genes, which leads to ethylene production, is differentially regulated from the expression of CPase, which leads to wilting, in carnation petals.

9.
Methods Inf Med ; 39(2): 134-7, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10892247

ABSTRACT

For the activation study of the brain, dipole localization from the scalp potential is one of the most promising techniques to realize a reasonable temporal resolution which cannot be realized in functional MR and PET. The goal of our study is to estimate inversely the electrical brain activity in the form of several dipoles from the scalp potential, using a network inversion technique. As a basic approach, we have inversely estimated several dipoles from the potential distribution on a spherical surface, in the homogeneous sphere model. In the training phase, by expanding the neural network input dimensions being redundant, the network can easily learn the forward mapping. In the inversion phase, the space of the expanded-network-input-vector can be narrowed by introducing a penalty term. Additionally, a consensus term was used to force several dipoles to have a similar orientation. We estimate that this is applicable to the localization of several dipoles that reflect the actual brain activity, especially in the visual evoked potentials.


Subject(s)
Brain Mapping , Electroencephalography , Evoked Potentials, Visual/physiology , Neural Networks, Computer , Signal Processing, Computer-Assisted , Humans , Visual Cortex/physiology
10.
Lipids ; 35(4): 461-6, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10858032

ABSTRACT

Ethyl esterification specificity of a lipase from Rhizomucor miehei for polyunsaturated fatty acids (PUFA) was compared at 1 and 100 mM to study molecular recognition of PUFA. The chemical shift of methylene adjacent to carboxyl groups in the nuclear magnetic resonance spectrum of docosahexaenoic acid (DHA) in ethanol moved to a lower magnetic field as the concentration of DHA increased, suggesting that the degree of dissociation of DHA decreased. Specificity constants or apparent second-order rate constants (Vmax/Km or catalytic power) for 1 mM esterification by immobilized lipases were higher than the native lipase. Immobilized hydrophobic carrier of low mass transfer resistance for the esterification substrate may improve maximal velocity and affinity for the substrate. Higher specificity constants for 1 mM substrates were observed using immobilized lipases fixed on an anion exchange resin with glutaraldehyde and on a cation exchange carrier with carbodiimide. Activity yields measured with 1 mM PUFA substrate were high. For the substrates at a concentration of 100 mM, higher specific constants with these bifunctional reagents were not observed but higher activity yields were found.


Subject(s)
Fatty Acids, Unsaturated/metabolism , Lipase/metabolism , Rhizomucor/enzymology , Anions , Carbodiimides , Cations , Docosahexaenoic Acids/chemistry , Docosahexaenoic Acids/metabolism , Enzymes, Immobilized , Esterification , Ethanol , Glutaral , Ion Exchange Resins , Kinetics , Magnetic Resonance Spectroscopy
11.
IEEE Trans Inf Technol Biomed ; 4(4): 306-19, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11206816

ABSTRACT

In this paper, we develop a general algorithm for decomposition and compression of grayscale images. The decomposition can be expressed as a functional relation between the original image and the Hadamard waveforms. The dynamic adaptive clustering procedure incorporates potential functions as a similarity measure for clustering as well as a reclustering phase. The latter is a multi-iteration, convergent procedure which divides the inputs into nonoverlapping clusters. These two techniques allow us to efficiently store and transmit a class of half-tone medical images such as magnetic resonance imaging (MRI) of the human brain. Due to the redundant image structure of MRI, obtained after the decomposition and clustering, almost half of the image can be omitted all together. Naturally, the compression rates for this specific type of grayscale image are increased greatly. A run-length coding is performed in order to compress further the retained information from the first two steps. Although all the techniques applied are simple, they represent an efficient way to compress grayscale images. The algorithm exhibits a performance which is competitive and often outperforming some of the methods reported in the literature.


Subject(s)
Algorithms , Image Interpretation, Computer-Assisted/methods , Brain/anatomy & histology , Cluster Analysis , Computer Simulation , Fourier Analysis , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Neural Networks, Computer
12.
Immunopharmacology ; 45(1-3): 35-8, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10614987

ABSTRACT

B1 or B2 kinin receptor-overexpressing HEK293 cells were stimulated with des-Arg9-BK or BK, respectively. Each agonist induced translocation of AP-1 into the nuclear fraction as well as activation of MAP kinases in each cells. MAP kinase inhibitor PD98059 suppressed translocation of AP-1 and agonist-induced MAP kinase activation in both cells. These results indicate that stimulation of B1 or B2 receptor expresses a feature of the signal transduction pathway of MAP kinase activation to translocation of AP-1. This signal transduction pathway of HEK cells through B1 and B2 receptors may be similar in response to respective agonists.


Subject(s)
Kidney/metabolism , MAP Kinase Signaling System/drug effects , Receptors, Bradykinin/physiology , Transcription Factor AP-1/metabolism , Animals , Bradykinin/analogs & derivatives , Bradykinin/pharmacology , Cells, Cultured , Humans , Kidney/embryology , Kidney/enzymology , Kidney/physiology , Rats , Receptor, Bradykinin B1 , Receptor, Bradykinin B2
13.
J Biol Chem ; 274(26): 18297-309, 1999 Jun 25.
Article in English | MEDLINE | ID: mdl-10373433

ABSTRACT

The flap endonuclease gene homologue from the hyperthermophilic archaeon, Pyrococcus horikoshii, was overexpressed in Escherichia coli and purified. The results of gel filtration indicated that this protein was a 41-kDa monomer. P. horikoshii flap endonuclease (phFEN) cleaves replication fork-like substrates (RF) and 5' double-strand flap structures (DF) using both flap endonuclease and 5'-3'-exonuclease activities. The mammalian flap endonuclease (mFEN) is a single-strand flap-specific endonuclease (Harrington, J. J., and Lieber, M. R. (1994) EMBO J. 13, 1235-1246), but the action patterns of phFEN appear to be quite different from those of mFEN at this point. The DF-specific flap endonuclease and 5'-exonuclease activities have not yet been reported. Therefore, this is the first report of the specific endo/exonuclease activities of phFEN. The DF-specific 5'-exonuclease activity degraded the downstream primer of 3' single-flap structure and was 15 times higher than the activities against nicked substrates without 3' flap strand. DF-specific flap endonuclease cleaved the 5' double-flap strand in DF and the lagging strand in RF at the junction portion. Because the RF appears to be the intermediate structure, due to the arrest of the replication fork, the double strand breaks after the arrests of the replication forks are probably caused by phFEN.


Subject(s)
DNA Repair , Endodeoxyribonucleases/genetics , Pyrococcus/enzymology , Amino Acid Sequence , Animals , Cloning, Molecular , Consensus Sequence , DNA, Archaeal/metabolism , Endodeoxyribonucleases/metabolism , Escherichia coli , Flap Endonucleases , Humans , Mice , Models, Chemical , Molecular Sequence Data , Pyrococcus/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Alignment , Substrate Specificity
14.
J Acoust Soc Am ; 105(5): 2695-703, 1999 May.
Article in English | MEDLINE | ID: mdl-10335620

ABSTRACT

A vibration-control mechanism for beams and columns was presented in our previous report in which the earthquake force was transformed into a vibration-control force by using a gear train mechanism. In our previous report, however, only the principle of transforming the earthquake force into the control force was presented; the discussion for real structures and the design method were not presented. The present article provides a theoretical analysis of the column which is used in multi-layered buildings. Experimental tests were carried out for a model of multi-layered buildings in the frequency range of a principal earthquake wave. Theoretical results are compared to the experimental data. The optimal design of the control mechanism, which is of importance in the column design, is presented. Numerical calculations are carried out for the optimal design. It is shown that vibrations of the column involving the mechanism are suppressed remarkably. The optimal design method and the analytical results are applicable to the design of the column.


Subject(s)
Disasters , Protective Devices , Vibration , Architecture , Models, Theoretical
15.
Am J Obstet Gynecol ; 180(4): 792-7, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10203646

ABSTRACT

OBJECTIVE: Endometriosis is a complex gynecologic disorder that may display features similar to malignancy, including aggressive growth and localized invasion of the myometrium or spread to various organs outside the uterus. Molecular studies of cancer have demonstrated that genomic instability involving chromosome 17 plays a role in the development and progression of various tumor types. These involve gain and/or loss, deletions, and mutations of candidate tumor suppressor genes (eg, BRCA1 and p53 ) on chromosome 17. STUDY DESIGN: We used a 2-color fluorescence in situ hybridization method for analysis of endometriotic and normal archival tissue. Centromere-specific and locus-specific p53 probes localized to chromosome 17 were selected to study 8 patients with late-stage (severe) endometriosis. Single cells localized to endometriotic lesions or normal endometrial glands were analyzed and identified as normal or abnormal on the basis of the distribution of fluorescence in situ hybridization signals. RESULTS: Overall, chromosome 17 aneuploidy was significantly greater (P <.05) in the endometriosis specimens (mean of 65%) than in normal endometrial cells (mean of 25%). No significant difference (P =.1071) in the distribution of fluorescence in situ hybridization signals was observed among the 5 normal endometrial specimens. However, significant differences (P <. 0001) were observed between the 8 endometriosis tissue specimens. CONCLUSION: We found increased heterogeneity of chromosome 17 aneuploidy in endometriosis. These findings support a multistep pathway involving somatic genetic alterations in the development and progression of this common disease.


Subject(s)
Aneuploidy , Chromosomes, Human, Pair 17 , Endometriosis/genetics , Endometrium/metabolism , Uterine Diseases/genetics , Case-Control Studies , Female , Humans , In Situ Hybridization, Fluorescence
16.
FEBS Lett ; 447(1): 25-8, 1999 Mar 19.
Article in English | MEDLINE | ID: mdl-10218575

ABSTRACT

From the genome sequence data of the thermophilic archaeon Pyrococcus horikoshii, an open reading frame was found which encodes a protein (332 amino acids) homologous with an endoglucanase from Clostridium thermocellum (42% identity), deblocking aminopeptidase from Pyrococcus furiosus (42% identity) and an aminopeptidase from Aeromonas proteolytica (18% identity). This gene was cloned and expressed in Escherichia coli, and the characteristics of the expressed protein were examined. Although endoglucanase activity was not detected, this protein was found to have aminopeptidase activity to cleave the N-terminal amino acid from a variety of substrates including both N-blocked and non-blocked peptides. The enzyme was stable at 90 degrees C, with the optimum temperature over 90 degrees C. The metal ion bound to this enzyme was calcium, but it was not essential for the aminopeptidase activity. Instead, this enzyme required the cobalt ion for activity. This enzyme is expected to be useful for the removal of N(alpha)-acylated residues in short peptide sequence analysis at high temperatures.


Subject(s)
Aminopeptidases/isolation & purification , Pyrococcus/enzymology , Aminopeptidases/genetics , Aminopeptidases/metabolism , Cations/analysis , Cloning, Molecular , Enzyme Stability , Escherichia coli/genetics , Hot Temperature , Metals/analysis , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Substrate Specificity
17.
FEBS Lett ; 435(1): 96-100, 1998 Sep 11.
Article in English | MEDLINE | ID: mdl-9755866

ABSTRACT

In response to bradykinin, phosphorylated MAP kinases (ERK-1 and ERK-2) were abundantly increased in HEK 293 cells, which overexpress the rat B2 kinin receptor. In a similar way des-Arg9-bradykinin stimulation of B1 kinin receptor-overexpressing HEK 293 cells caused activation of the same species of MAP kinase. Furthermore, nuclear translocation of transcription factor AP-1 was also found in the cells after stimulation with either agonist. PD98059, a MAP kinase kinase (MEK-1) inhibitor, blocked the agonist-induced AP-1 translocation as well as the phosphorylation of the MAP kinases. This communication provides the first evidence for both B1 and B2 kinin receptors mediating the MAP kinase signaling pathway to activate AP-1.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Receptors, Bradykinin/agonists , Signal Transduction/physiology , Transcription Factor AP-1/metabolism , Animals , Biological Transport , Bradykinin/analogs & derivatives , Bradykinin/pharmacology , Bradykinin Receptor Antagonists , Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors , Calcium-Calmodulin-Dependent Protein Kinases/physiology , Cell Line , Consensus Sequence , Electrophoresis, Polyacrylamide Gel , Enzyme Activation/drug effects , Flavonoids/pharmacology , Humans , Oligonucleotides/metabolism , Rats , Rats, Inbred BN , Rats, Sprague-Dawley , Receptor, Bradykinin B1 , Receptor, Bradykinin B2 , Receptors, Bradykinin/biosynthesis , Signal Transduction/drug effects , Transcription Factor AP-1/drug effects
18.
Clin Chim Acta ; 278(1): 35-43, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9877122

ABSTRACT

N-Acetyl-beta-D-glucosaminidase (NAG) is a widely used urinary enzyme for the assessment of renal diseases. We studied the stabilities of NAG isoenzymes in urine at 37 degrees C by enzyme assay and ELISA using a model simulating in vivo conditions. The stabilities were found to be affected by the pH. Under mild acidic condition (about pH 6), there was no significant loss of enzymatic activity of NAG isoenzyme A, enzymatic activity of NAG isoenzyme B and immunological activity of NAG isoenzyme B even after 8 h incubation. In contrast, under alkaline condition (about pH 8), the enzymatic activity of NAG isoenzyme A was rapidly lost, whereas both enzymatic and immunological activities of NAG isoenzyme B were maintained at more than 80% of their initial values. Also, we found that the ratios of endogenous NAG isoenzyme B to total NAG were elevated in alkaline urine samples. These results indicate that NAG isoenzyme A, which is a major isoenzyme in normal urine (pH 5-7), seems to be inactivated in alkaline urine. Our results suggest that for alkaline urine, NAG isoenzyme B should be measured to avoid misinterpretation of total NAG enzymatic activities.


Subject(s)
Acetylglucosaminidase/urine , Isoenzymes/urine , Bacterial Infections/enzymology , Bacterial Infections/urine , Enzyme Stability , Hot Temperature , Humans , Hydrogen-Ion Concentration , Pyelonephritis/enzymology , Pyelonephritis/urine
19.
Clin Chem ; 43(4): 569-74, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9105256

ABSTRACT

We have developed a new ELISA for quantifying N-acetyl-beta-D-glucosaminidase (NAG) isoenzyme B in human urine after raising monoclonal antibodies against the isoenzyme from human placenta. Though the obtained antibodies reacted not only to isoenzyme B but also to A, we could detect isoenzyme B selectively by a two-step sandwich ELISA with a pair of selected antibodies at low pH in the first reaction. The detected limit was 0.5 microgram/L for a sample volume of 25 microL. Within-run CVs ranged from 2.5% to 5.4% and between-run CVs ranged from 6.2% to 9.1%. Recoveries of NAG isoenzyme B added to each of three urine samples ranged from 91% to 114%. The dilution curves of urine samples showed good linearity. The cross-reactivity of NAG isoenzyme A was practically negligible (2-3%). The mean value for NAG isoenzyme B in spot urines from healthy adults was 2.9 micrograms/g creatinine. This ELISA method is rapid and precise enough for routine determination of NAG isoenzyme B in human urine.


Subject(s)
Acetylglucosaminidase/urine , Enzyme-Linked Immunosorbent Assay/methods , Isoenzymes/urine , Acetylglucosaminidase/immunology , Acetylglucosaminidase/isolation & purification , Adult , Antibodies, Monoclonal/immunology , Antigens/immunology , Chromatography, Ion Exchange , Female , Humans , Hydrogen-Ion Concentration , Isoenzymes/immunology , Isoenzymes/isolation & purification , Kidney Diseases/enzymology , Male , Placenta/enzymology , Reference Values , Sensitivity and Specificity
20.
Plant Cell Physiol ; 38(3): 312-8, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9150604

ABSTRACT

We partially purified 1-aminocyclopropane-1-carboxylate (ACC) oxidase from senescing petals of carnation (Dianthus caryophyllus L. cv. Nora) flowers and investigated its general characteristics, and, in particular, the inhibition of its activity by ACC analogs. The enzyme had an optimum pH at 7-7.5 and required Fe2+, ascorbate and NaHCO3 for its maximal activity. The Km for ACC was calculated as 111-125 microM in the presence of NaHCO3. Its M(r) was estimated to be 35 and 36 kDa by gel-filtration chromatography on HPLC and SDS-PAGE, respectively, indicating that the enzyme exists in a monomeric form. These properties were in agreement with those reported previously with ACC oxidases from different plant tissues including senescing carnation petals. Among six ACC analogs tested, 1-aminocyclobutane-1-carboxylate (ACBC) inhibited most severely the activity of ACC oxidase from carnation petals. ACBC acted as a competitive inhibitor with the Ki of 20-30 microM. The comparison between the Km for ACC and the Ki for ACBC indicated that ACBC had an affinity which was ca. 5-fold higher than that of ACC. Whereas ACC inactivated carnation ACC oxidase in a time-dependent manner during incubation, ACBC did not cause the inactivation of the enzyme. Preliminary experiments showed that ACBC and its N-substituted derivatives delayed the onset of senescence in cut carnation flowers.


Subject(s)
Amino Acid Oxidoreductases/antagonists & inhibitors , Amino Acids, Cyclic , Amino Acids/pharmacology , Plants/enzymology , Amino Acid Oxidoreductases/isolation & purification , Blotting, Western , Chromatography, Gel , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Kinetics , Plant Physiological Phenomena , Time Factors
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