Fill-in after reinjection of Tc-99m MAA.
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Aged↗
Biomedical subjects
N Watanabe
Publications and source records attributed to N Watanabe.
Bone imaging in advanced gastric cancer.
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Aged↗
Malignant melanoma imaging with Tl-201.
Two patients with malignant melanoma were evaluated using Tl-201 scintigraphy. Planar scintigraphy showed tumor accumulation, and SPECT Tl-201 imaging revealed exact tumor localization. The findings indicate the utility of Tl-201 to detect the primary lesion and to identify postoperative recurrence in malignant melanoma.
Aged↗
In vitro effect of contrast agents during immunoradiometric assay for tumour-associated antigens.
The aim of this study was to investigate if contrast agents interfere with the performance of an immunoradiometric assay (IRMA) in vitro for serum tumour-associated antigen. Each of five carcinoembryonic antigen (CEA)-positive sera, CA-130-positive sera and tissue polypeptide antigen (TPA)-positive sera was mixed with six contrast agents: Ioversol 350, Iopamidol 370, Iomeprol 300, Iomeprol 400, Iohexol 300 and Gadopenteic acid in 50:50, 50:20, 50:5.0, 50:1.0, 50:0.5 and 50:0.1 microl proportions. Following IRMA, the interference of binding rates in each mixture was calculated, and the serum concentrations of CEA, CA-130 and TPA were estimated and compared with the originals. All contrast agents used were able to inhibit the binding rate with IRMA and the inhibition rates were in proportion to the amount of contrast agent. The detection of serum concentrations of CEA, CA-130 and TPA was significantly inhibited in the mixtures with more than 5.0 microl of contrast agent in all cases. Apart from Iomeprol 400, there was no significant inhibition of detection at the lowest concentrations of contrast agents. Iomeprol 400 was the strongest inhibitor and Gadopenteic acid the weakest inhibitor for each IRMA of the contrast agents employed. In conclusion, our results demonstrate that contrast agents may reduce the immunoreaction of antibody and antigen and lead to in vitro inhibition during immunoassays. It would be unwise to perform any plasma/serum immunoassay on a sample collected within 24 h of the administration of contrast agent considering the pharmacokinetics.
Aged↗
Reproducibility of 99Tcm-MAG3 clearance in normal volunteers with the two-sample method: comparison with 131I-OIH.
The aim of this study was to evaluate the reproducibility of 99Tcm-mercaptoacetyltriglycine (99Tcm-MAG3) clearance and to compare it with that of 131I-orthoiodohippurate (131I-OIH), which is widely used in clinical practice. Twelve young healthy volunteers with a mean age of 23.4 years (range 19-28) were enrolled in the study. The investigations were repeated at an interval of 1 month under similar physiological conditions. Each volunteer received a simultaneous injection of 99Tcm-MAG3 and 131I-OIH that was commercially available in an already labelled form. Blood samples were obtained at 44 and 104 min post-injection. Clearance values were calculated using the two-sample method. The mean (+/- S.D.) change from the first to the second measurement was -7.1 +/- 11.1% for 99Tcm-MAG3 and 1.7 +/- 13.6% for 131I-OIH. There were no significant differences between the first and the second measurements of 99Tcm-MAG3 and 131I-OIH clearance, respectively. 99Tcm-MAG3 clearance was shown to be very similar to that of 131I-OIH in healthy volunteers.
Adult↗
Molecular characterization of photomixotrophic tobacco cells resistant to protoporphyrinogen oxidase-inhibiting herbicides
Peroxidizing herbicides inhibit protoporphyrinogen oxidase (Protox), the last enzyme of the common branch of the chlorophyll- and heme-synthesis pathways. There are two isoenzymes of Protox, one of which is located in the plastid and the other in the mitochondria. Sequence analysis of the cloned Protox cDNAs showed that the deduced amino acid sequences of plastidial and mitochondrial Protox in wild-type cells and in herbicide-resistant YZI-1S cells are the same. The level of plastidial Protox mRNA was the same in both wild-type and YZI-1S cells, whereas the level of mitochondrial Protox mRNA YZI-1S cells was up to 10 times the level of wild-type cells. Wild-type cells were observed by fluorescence microscopy to emit strong autofluorescence from chlorophyll. Only a weak fluorescence signal was observed from chlorophyll in YZI-1S cells grown in the Protox inhibitor N-(4-chloro-2-fluoro-5-propagyloxy)-phenyl-3,4,5, 6-tetrahydrophthalimide. Staining with DiOC6 showed no visible difference in the number or strength of fluorescence between wild-type and YZI-1S mitochondria. Electron micrography of YZI-1S cells showed that, in contrast to wild-type cells, the chloroplasts of YZI-1S cells grown in the presence of N-(4-chloro-2-fluoro-5-propagyloxy)-phenyl-3,4,5, 6-tetrahydrophthalimide exhibited no grana stacking. These results suggest that the herbicide resistance of YZI-1S cells is due to the overproduction of mitochondrial Protox.
Journal Article↗
Oxidative stress and mitochondrial damage precedes gastric mucosal cell death induced by ethanol administration.
Although it has been speculated that active oxidants and mitochondrial membrane damages play roles in ethanol-induced gastric mucosal damages, its detail remains unknown. The present study was designed to investigate whether ethanol induces oxidative stress and mitochondrial permeability transition (MPT) before cell death of gastric mucosal cells. Rat gastric mucosal cells (RGM-1) were kept in serum-free Dulbecco's modified Eagle's medium before addition of various concentrations of ethanol. Nuclear morphological aftemations and membrane barrier dysfunction of RGM-1 cells were assessed by staining with Hoechst 33342 and propidium iodide, respectively. To assess the contribution of oxygen-derived free radicals and intracellular glutathione, scavenger of hydrogen peroxide and the hydroxyl radical, N,N-dimethylthiourea, glutathione precursor, N-acetyl-L-cysteine, and an inhibitor of alcohol dehydrogenase, 4-methylpyrazole were added before treatment with ethanol. To investigate MPT, calcein and tetramethylrhodamine methyl ester were loaded before addition of ethanol, and the changes of fluorescence intensity were monitored using a laser scanning confocal microscope. Ethanol (>5% v/v) dose-dependently increased the number of propidium iodide-positive cells, suggesting a diminished barrier function of cell membrane. After addition of ethanol, mitochondria were filled quickly with calcein indicating MPT, which was accompanied by mitochondrial depolarization, as shown by loss of tetramethylrodamine methyl ester before cell death. Ethanol-induced cell death was significantly attenuated by simultaneous incubation with either N,N-dimethylthiourea or N-acetyl-L-cysteine, suggesting the importance of intracellular redox states in inducing cellular damage, whereas such change was not attenuated by 4-methylpyrazole. Present results suggest that ethanol treatment induces intracellular oxidative stress and produces MPT and mitochondrial depolarization, which are preceding cell death in gastric mucosal cells. Intracellular antioxidants, such as glutathione, may have a significant protective action against ethanol in gastric mucosal cells.
Animals↗
An enzyme immune assay for serum anti-acetaldehyde adduct antibody using low-density lipoprotein adduct and its significance in alcoholic liver injury.
An acetaldehyde (AcH) adduct was prepared using rabbit low-density lipoprotein as carrier proteins. An antibody against this adduct was raised in Watanabe heritable hyperlipidemic rabbits and cross-reacted with human low-density lipoprotein and bovine serum albumin adducts. Using this antibody, serum anti-AcH-adduct antibody levels were measured by a direct ELISA method in 56 Japanese adults (healthy adults and patients with nonalcoholic gastrointestinal diseases, alcoholic liver injury, or alcoholic pancreatitis). The antibody level (mean +/- SD) was 22 +/- 10 microg/ml in healthy adults, 22 +/- 11 microg/ml in nonalcoholic gastrointestinal diseases, and 16 +/- 13 microg/ml in alcoholic pancreatitis. These antibody levels tended to increase with the progression of alcoholic liver injury, starting from fatty liver via hepatitis to cirrhosis, 29 +/- 24 microg/ml in fatty liver, 35 +/- 29 microg/ml in alcoholic hepatitis, and 46 +/- 54 microg/ml in alcoholic cirrhosis. The antibody level in patients taking 100 g or more of ethanol per day tended to be higher, compared with those in people taking less ethanol. A follow-up observation revealed that alcohol abstinence after hospitalization raised serum anti-AcH-adduct antibody level in some patients and kept it constantly low in other patients. The immunohistochemical study using the anti-AcH-adduct antibody revealed the presence of adduct-like substance in hepatocytes of liver biopsy specimens obtained from patients with alcoholic liver disease. The results indicate that the anti-AcH-adduct antibody may be associated with the progress of alcoholic liver diseases.
Acetaldehyde↗
Rhenium-186-mercaptoacetyltriglycine-labeled monoclonal antibody for radioimmunotherapy: in vitro assessment, in vivo kinetics and dosimetry in tumor-bearing nude mice.
Stability and immunoreactivity of 186Re-labeled monoclonal antibody were examined, and its in vivo kinetics was investigated in tumor-bearing Balb/c nu/nu female mice to assess the feasibility of using it in radioimmunotherapy (RIT). A murine IgG1, A7, against a 45 kD glycoprotein in human colon cancer was radiolabeled with 186Re by using a chelating method with a mercaptoacetyltriglycine (MAG3). 186Re-MAG3 complex was conjugated to A7 after esterification of 186Re-MAG3 with tetrafluorophenol (TFP). The efficiency of 186Re-MAG3-TFP production and the labeling efficiency of A7 were 51-59% and 57-60%, respectively. Immunoreactivity of purified 186Re-MAG3-A7 was 68.2% at infinite antigen excess. In 0.9% NaCl at 4 degrees C, the radioactivity (12.7 MBq/mg, 3.55 MBq/ml) dissociated with time from 186Re-MAG3-A7 as a small molecular weight moiety because of autoradiolysis. The addition of ascorbic acid, 5 mg/ml, as a radioprotectant or storage at -80 degrees C could effectively prevent the radiolysis of 186Re-MAG3-A7 for 7 days. Immunoreactivity of 186Re-MAG3-A7, 6.70 MBq/mg (6.66 MBq/ml), stored in the presence of ascorbic acid was well retained up to 8 days after the preparation. In colon cancer xenografted mice, 31.0% of the injected dose/g of 186Re-MAG3-A7 had accumulated in the tumors at 24 h postinjection. Estimated radiation dose to tumors was 14.9 cGy/37 kBq up to 8 days postinjection which was 12-fold greater than the whole-body radiation dose. These in vivo characteristics were superior to those of A7 labeled with radioiodine, affording greater therapeutic ratios than 131I-A7. Because of the better image quality of 186Re-MAG3-A7 as well as more favorable dosimetry, 186Re-MAG3-A7 would be a better choice for RIT of colon cancer than 131I-A7. These results indicated the feasibility of RIT with 186Re-MAG3-A7, though the prevention of radiolysis of the labeled antibody should be considered.
Animals↗
Comparison of two interferon alfa treatment regimens characterized by an early virological response in patients with chronic hepatitis C.
OBJECTIVE: We investigated the efficacy of an interferon regimen characterized by an early virological response in patients with chronic hepatitis C and evaluated whether the patient's virological status during therapy would be useful for predicting a complete response. METHODS: We treated 62 patients with chronic hepatitis C with 6 million units (MU) of human lymphoblastoid interferon daily for 4 wk. The serum HCV RNA was assayed at week 2 by the reverse transcription-polymerase chain reaction. HCV RNA-negative patients (group A) received 6 MU of interferon three times weekly for an additional 22 wk (total dose, 564 MU). HCV RNA-positive patients were randomly assigned to group B-1, which received the same regimen as group A, or to group B-2, which received 6 MU of interferon daily for 4 wk followed by 6 MU three times weekly for 18 wk (total dose, 660 MU). RESULTS: Complete responses were achieved by 19 (63.3%) of 30 group A patients, compared with one (6.3%) of 16 group B-1 patients and none of 16 group B-2 patients. The virological response at week 2 and the pretreatment serum HCV RNA level were independent significant predictors of a complete response. CONCLUSION: Patients who were still HCV RNA-positive at week 2 were unlikely to achieve a complete response after interferon therapy. An increase in the total dose of interferon failed to yield further benefit in these patients.
Adult↗
[Analysis of transmission of Burkholderia cepacia isolates in an intrahospital by randomly amplified polymorphic DNA-PCR method].
Strains of Burkholderia cepacia isolated in our hospital from November 1995 to September 1996 were classified with randomly amplified polymorphic DNA-PCR (RAPD-PCR) and conventional biochemical tests (ID test.NF-18, API20NE, and Neg Combo 4J kit), and intrahospital isolates of B. cepacia were analysed. During the period 28 strains from inpatients and 2 from medical apparatus were isolated. Twenty four of 28 (85.7%) were from sputum. In 1996 from January to February, 20 strains were detected from 8 inpatients, and two strains were from the nebulizers at the Trauma and Critical Care Center (TCC). With typing of B. cepacia by conventional methods no epidemiological relations among isolates were found. However, DNA patterns of original isolates from the nebulizers at TCC by RAPD-PCR were identical with those of isolates in sputa from patients in other wards who had stayed at TCC, indicating that TCC was an initial source of transmission and the strain was transmitted with the patients to the wards. These results suggest that RAPD-PCR method might be a useful tool to analyse an epidemiological survey for intrahospital transmission of isolate.
Burkholderia Infections↗
Stereoselective disposition of sulbenicillin in humans.
Stereoselective disposition of sulbenicillin (SBPC) epimers in healthy human volunteers was studied in order to clarify the differences in pharmacokinetic behavior between the epimers. Stereospecific high-performance liquid chromatography was used for the determination of SBPC epimers. Plasma protein binding was measured in vitro with an ultrafiltration method. The binding was stereoselective, with the unbound fraction (fu) of the R-epimer being approximately 1.3-fold greater than that of the S-epimer. SBPC was administered intravenously to human volunteers, and concentrations of SBPC in plasma and urinary excretion rates were measured. Renal clearance (CLR) for the unbound drug (approximately 400 ml/min) was greater than the glomerular filtration rate (GFR) (approximately 109 ml/min) for both epimers, suggesting that both epimers are secreted at the renal tubules. Renal tubular secretion appeared to be greater for the S-epimer. When probenecid was coadministered, the CLR values of both epimers were significantly reduced and were approximately equal to the GFR values. CLR was greater for the S-epimer (37.5 and 49.8 ml/min for R-SBPC and S-SBPC, respectively), which was simply due to the greater fu of the S-epimer in plasma. In contrast, total body clearance was greater for the R-epimer (67.8 and 56.3 ml/min for R-SBPC and S-SBPC, respectively) because of the stereoselective degradation of the R-epimer in plasma. It was revealed that stereoselective degradation in the body had significant influence on the disposition of SBPC epimers.
Adult↗
Induction of endothelin-1 synthesis by IL-2 and its modulation of rat intestinal epithelial cell growth.
Endothelin (ET), a vasoconstrictive peptide, is known to have a variety of biological actions. Although ET is released by vascular endothelial cells, other cell populations also have been reported to synthesize and release ET. In this study, we examined whether ET is synthesized by intestinal epithelial cells and whether it affects induction of epithelial cell proliferation by interleukin-2 (IL-2). Subconfluent monolayers of intestinal epithelial cells (IEC-6 and IEC-18) were maintained in serum-free medium before addition of rat IL-2. Both IEC-6 and IEC-18 cells released ET-1 into the medium under unstimulated conditions, as determined by a sandwich ELISA. IL-2 significantly enhanced ET-1 release in a time-dependent manner. ET-3 was not detectable in the culture media of either cell line. Expression of ET-1 and ET-3 mRNA in epithelial cells was assessed by competitive PCR. Both cell lines were shown to express ET-1 mRNA, but no ET-3 mRNA was detected. IL-2 treatment enhanced ET-1 mRNA expression by both IEC-6 and IEC-18 cells. Both cell lines also expressed mRNA for ETA and ETB receptor subtypes. When cell proliferation was assessed, exogenous ET-1 induced a slight proliferative response in both types of cells that was consistent and significant at low ET-1 concentrations; cell growth was inhibited at a higher concentration (10(-7) M). IL-2 produced a significant proliferative response in both cell lines. However, the addition of ET-1 (10(-7) M) to culture media attenuated the IL-2-induced increase in cell proliferation. ETA-receptor antagonists significantly enhanced cellular proliferation, suggesting involvement of the ETA receptor in modulation of IL-2-induced intestinal epithelial cell growth.
Animals↗
Cloning, functional characterization, and localization of a rat renal Na+-dicarboxylate transporter.
We report here the isolation, functional characterization, tissue distribution, and membrane localization of rat renal Na+-dicarboxylate transporter (rNaDC-1). rNaDC-1 consists of 2,245 nucleotides, and the deduced amino acid sequence showed 73% and 75% identity to rabbit and human NaDC-1, respectively. When expressed in Xenopus laevis oocytes, rNaDC-1 mediated sodium-dependent uptake of di- and tricarboxylates. Substrates of rNaDC-1 evoked inward currents in oocytes expressed with rNaDC-1; succinate, alpha-ketoglutarate, and glutarate were relatively high-affinity substrates, and citrate was a low-affinity substrate of rNaDC-1. The coupling ratio of citrate to charge was determined to be 1:1 at pH 7.4; influx of one positive charge per citrate molecule suggests a symport of three Na+ with a divalent citrate. Expression of rNaDC-1 mRNA was detected in the kidney and the small and large intestines. Immunohistochemistry using polyclonal antibodies raised against the 14 amino acids at the COOH terminus of rNaDC-1 revealed that rNaDC-1 is localized exclusively in the luminal membrane of S2 and S3.
Amino Acid Sequence↗
Micturitional disturbances due to labial adhesion.
We report 2 cases of micturitional disturbances due to labial adhesion. Two women, aged 78 and 77 years old, visited our hospital with chief complaints of difficult voiding and urinary retention. On examination, their labias were found to be extensively fused. In both cases, the labial adhesions were separated by surgical repair under spinal anesthesia. Gentamicin and steroid ointments were used to prevent readhesion of the labia postoperatively.
Aged↗
The increase of memory T cell subsets in children with idiopathic nephrotic syndrome.
Two-color and three-color flow cytometry was carried out to determine whether the memory T cells (CD45RO+ T cells) play a major role in lymphocyte dysfunction of 26 children with idiopathic nephrotic syndrome (INS). The INS patients were divided into three groups: (1) 10 patients who were not receiving glucocorticoid hormone (GCH) and were suffering from acute nephrotic state were referred to as N1; (2) 8 patients who were in remission maintained by GCH therapy alone were referred to as N2; (3) 8 patients who were free of GCH therapy for at least 4 months were referred to as N3. Group N1 demonstrated a significant increase in the percentage of CD45RO+CD4+ T cells and CD45RO+CD8+ T cells (p < 0.05) compared with 11 controls, and these subsets were noted to have a tendency to decrease to control levels in groups N2 and N3. Furthermore, interleukin-2 receptor-alpha expressed subsets in CD45RO+CD4+ T cells (CD45RO+CD4+CD25+ T cells) were also increased only in group N1 (p < 0.02). A similar tendency of absolute counts was observed in these subsets. These results suggest that activated memory T cells reflect lymphocyte dysfunction at initial onset or relapse in INS children.
Antibodies, Monoclonal↗
The involvement of CD80 and CD86 costimulatory molecules in the induction of eosinophilia in mice infected with Nippostrongylus brasiliensis.
The costimulatory signal provided by the interaction between CD28 and its ligands, CD80 and CD86, is critical for T cell activation. The requirement of CD80 and CD86 in T cell activation for eosinophilia and IgE production was examined in mice infected with the nematode parasite Nippostrongylus brasiliensis. Combined treatment with anti-CD80 and anti-CD86 suppressed eosinophilia in the blood and the small intestine and suppressed IgE production. However, administration of either anti-CD80 or anti-CD86 alone had little effect on eosinophilia and on the elevation of IgE levels. These results suggest that CD80 and CD86 costimulation is required and either CD80 or CD86 can provide a sufficient costimulatory signal for induction of eosinophilia in mice infected with N. brasiliensis.
Animals↗
Enhancement of hydroxyl radical DNA cleavage by serum anti-dsDNA antibodies in SLE.
Autoantibodies reactive with double-stranded (ds) DNA are a hallmark of systemic lupus erythematosus (SLE), but it is not fully elucidated how these antibodies contribute to the various pathological changes observed in lupus patients. In a previous study, we have found a significant enhancement effect of two murine monoclonal anti-dsDNA antibodies on DNA cleavage by the hydroxyl radical. We have extended this study and have found that purified polyclonal anti-dsDNA antibodies from sera of lupus patients and an MRL/lpr mouse, but not anti-ssDNA antibodies, also enhanced radical cleavage of DNA. The cleavage was inhibited by EDTA, DMSO and thiourea. The antibody preparations per se did not cleave DNA. These results suggest that such an enhancement effect on DNA cleavage is a feature of a significant part of anti-dsDNA antibody population and a possible clue in understanding the roles of anti-dsDNA antibodies in the pathophysiology of SLE under certain circumstances.
Administration, Topical↗