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Biomedical subjects

N Tanaka

Publications and source records attributed to N Tanaka.

At least 19 recordsLinked to original sources
PubMed1992

[Abnormal chest shadow on CT in immunosuppressed patients].

An abnormal chest shadow was observed on CT scans in 25 cases of 23 immunosuppressed patients. Pulmonary disease was pathologically confirmed to be pneumocystis carinii pneumonia (PC pneumonia) in four patients, cytomegalovirus pneumonia (CMV pneumonia) in one, bacterial pneumonia in seven, fungal infection in three, miliary tuberculosis in one, leukemic infiltration in two, lymphangitis carcinomatosa in three, drug-induced pneumonitis in three, and ARDS in one. In almost all patients, especially those with infectious diseases such as PC pneumonia, CMV pneumonia, and bacterial pneumonia, the abnormal shadow was wide and visible in the bilateral lung fields. We presumed that such findings as lobular shadow, centrilobular shadow, and mosaic pattern reflected the extension of disease via the respiratory tract, and that those findings are typical of infectious diseases. Because such findings as abnormal linear shadow and swelling of a broncho-vascular bundle were very frequently recognized in patients with lymphangitis carcinomatosa and frequently recognized in those with drug-induced pneumonitis, these diseases may be distinguished from other diseases. An area of slightly increased density was frequently recognized in patients with PC pneumonia, bacterial pneumonia, and drug-induced pneumonitis. Such lesions were pathologically confirmed to be located in the interstitium and/or alveolus. CT was extremely useful in comprehending the character and extension of particular diseases among various diseases. As the number of patients studied was small, the utility of CT in immunosuppressed patients requires further investigation in a larger number of patients.

Adolescent↗
PubMed1992

[Determination of common esterase D phenotypes by HPLC].

The analysis of blood Esterase D (ESD) phenotypes was performed by using high performance liquid chromatography (HPLC). The hemolysate was first treated with a cation exchanger to remove hemoglobin, injected into HPLC on a weak anion exchange column, and developed to become fluorescent with reaction reagent. The chromatogram of each ESD phenotype was distinct from those of the other phenotypes. ESD protein was confirmed by isoelectric focusing in the HPLC fraction that was referred for ESD typing. This HPLC method can be used to determine the common ESD phenotypes in blood.

Adult↗
PubMed1992

[Prediction of ovulation by urinary LH surge].

To investigate the usefulness of a semi-quantitative assay of urinary luteinizing hormone (LH) for predicting ovulation, the relationship among urinary LH, serum LH, serum estradiol (E2) and ultrasonographic observations of follicles were examined in 32 infertile women (35 cycles) at spontaneous (7), clomiphene (13) or cyclofenil (3) induced or hMG (12) induced cycles. Their urine samples were collected 3 times a day for LH assay, starting from about the 10th cycle day or when follicles having a diameter of 10mm or more were detected to the day of ultrasonographical confirmation of follicle ruptures. In the morning on these days, blood was taken twice daily for LH and E2 determination at intervals of 30 min. In spontaneous cycles, urinary LH was (P < 0.001) correlated to a significant extent with the serum LH and E2 levels, and follicle rupture was observed 1.9 days after the urine LH surge. In contrast, there was no significant correlation between the urine LH and serum LH or E2 levels in the ovulation induced cycles. In addition, the period from urine LH positive to follicle rupture was significantly (P < 0.05) prolonged in those cycles compared with that in spontaneous cycles. These results suggested that the urine LH determination was good for predicting ovulation in spontaneous cycles, but it was also necessary to monitor the follicle sizes by ultrasonography in ovulation induced cycles.

Adult↗
PubMed1992

Boy with a chromosome del (3)(q12q23) and blepharophimosis syndrome.

We report on a 6-year-old boy with de novo 46,XY,del(3)(q12q23) and bilateral blepharophimosis, ptosis, epicanthus inversus, in addition to multiple other anomalies. Since 4 previously reported cases of interstitial deletion of 3q involving 3q23 band are clinically similar, we propose this blepharophimosis sequence due to 3q23 deletion as a further "contiguous gene syndrome."

Adult↗
PubMed1992

Cancer-associated glycoproteins defined by a monoclonal antibody, MLS 128, recognizing the Tn antigen.

A murine monoclonal antibody, MLS 128, recognizing the Tn antigen, was established and used for characterization of glycoproteins expressing the Tn antigen. The Tn antigen was expressed on three polypeptide chains with molecular weights of 250k, 210k and 150k daltons. LS 180 cells were labeled with 3H-glucosamine or 35S-sulfate metabolically, and then the immunoprecipitate derived from the cell lysate was subjected to SDS-PAGE followed by fluorography. It was revealed that these Tn antigen glycoproteins were produced through the processing of a high molecular weight precursor. The carbohydrate moieties of the Tn antigen glycoproteins labeled with 3H-glucosamine were released with alkaline-borohydride, and the released sugars were examined by gel filtration and paper chromatography. The carbohydrates predominantly consisted of GalNAc and sialyl GalNAc (greater than 90%), with a nearly equal distribution.

Antibodies, Monoclonal↗
PubMed1992

An ultrasensitive system to detect IL-4: enzyme-linked immunosorbent assay (ELISA) combined with an avidin-biotin and enzyme amplification system.

We established an ultrasensitive interleukin-4 enzyme-linked immunosorbent assay by combining ELISA with an avidin-biotin and enzyme amplification system. The resultant system (AB-EA ELISA) was 250 times more sensitive than conventional ELISA and 2.5 times more sensitive than enhanced ELISA using an enzyme amplification system alone. The ultrasensitive assay was specific to IL-4 alone; there was no cross reaction with other cytokines. Using the ultrasensitive assay, we measured IL-4 synthesis in vitro by unstimulated and stimulated peripheral blood mononuclear cells (PBMC) from patients with allergic rhinitis. PBMC from patients spontaneously produced measurable amounts of IL-4, whereas IL-4 production from PBMC of normal controls, if any, was below detectable levels. Stimulation of the cultures with LPS significantly increased IL-4 production in two of six patient PBMC cultures but in none of the control cultures; stimulation with Con A markedly increased IL-4 production in all patient PBMC cultures but in only two of seven control cultures. These results suggest that the AB-EA ELISA is a useful method to study the mechanism of IL-4 synthesis in type-I allergic diseases.

Animals↗
PubMed1992

Cloning of the gamma chain of the human IL-2 receptor.

A third subunit, the gamma chain, of the human interleukin-2 receptor (IL-2R) was identified, and a complementary DNA clone encoding this member of the cytokine receptor family was isolated. The gamma chain is necessary for the formation of the high- and intermediate-affinity receptors, which consists of alpha beta gamma heterotrimers and beta gamma heterodimers, respectively. The IL-2R on murine fibroblastoid cells can be internalized after binding IL-2 only if the gamma chain is present; alpha and beta are insufficient for internalization. Thus, the gamma chain is an indispensable component of the functional IL-2R.

Amino Acid Sequence↗
PubMed1992

Kinetic studies on CO binding to reconstituted myoglobins with four synthetic hemes; structural control in ligand binding to myoglobin.

Examination was made of CO binding reactions to four kinds of modified sperm whale myoglobin (Mb), whose heme was reconstituted by iron complexes of synthetic porphyrins such as porphine (Por), meso-tetramethylporphyrin (TMeP), meso-tetraethylporphyrin (TEtP) and meso-tetra(n-propyl)porphyrin (TnPrP), using flash photolysis and stopped-flow methods. The CO association rate was found to be 5- to 20-times and dissociation rate 10- to 36-times accelerated by replacement with synthetic hemes. These features could be explained based on characteristic structures of modified Mbs indicated by X-ray crystallography. The side chain of Arg-45 protruded from the heme vicinity into the solvent region and heme was tilted by interactions of meso-alkyl side chains with surrounding peptides, resulting in the formation of widely opened channels and pockets for ligand passage. These structural features indicate the CO ligand to more easily enter or exit from heme pockets of reconstituted myoglobins, compared to native Mb.

Animals↗
PubMed1992

[Evaluation of breath-hold multislice dynamic MRI of hepatocellular carcinomas].

The breath-hold multislice dynamic study (BMDS) in MRI, which can scan the entire liver during a single breath-holding, was applied to 16 patients with 30 focal lesions of hepatocellular carcinoma (HCC). The BMDS was performed at 20 seconds and 3 minutes after the bolus injection of Gd-DTPA, by gradient echo pulse sequence (FLASH). 29 nodules were detected in the BMDS, showing rapid enhancement on early phase and decline on delayed phase images. The BMDS was more sensitive than conventional MR images. Therefore, the BMDS seems to be useful for the diagnosis of HCC with multiple as well as solitary nodules.

Carcinoma, Hepatocellular↗
PubMed1992

Loss of heterozygosity on the long arm of chromosome 22 in pheochromocytoma.

To identify the putative common deleted region on the long arm of chromosome 22 in pheochromocytoma, restriction fragment length polymorphism analysis was performed in 17 pheochromocytomas. All cases were heterozygous for at least one of the eight marker loci on 22q. Loss of heterozygosity (LOH) was observed in nine pheochromocytomas, of which eight were hereditary and one nonhereditary. Three pheochromocytomas had interstitial deletions that enabled us to localize the commonly deleted region as distal to D22S10 and proximal to D22S22. Hereditary pheochromocytoma frequently occurs in association with medullary thyroid carcinoma (MTC). Therefore, we also studied allelic loss on 22q in 23 hereditary MTCs. Only one of the MTCs showed LOH on 22q. Recent studies have mapped tumor suppressor loci associated with meningioma and neurofibromatosis type 2 (NF2) to 22q. The commonly deleted region in pheochromocytoma found by us encompasses the regions to which tumor suppressor genes associated with NF2 and meningioma have been mapped. The exact role of the pheochromocytoma tumor suppressor gene on 22q and its relationship to the suppressor genes involved in NF2 and meningioma remain unknown.

Adrenal Gland Neoplasms↗
PubMed1992

Protease inhibitors (gebexate mesylate and ulinastatin) stimulate intracellular chemiluminescence in human neutrophils.

The effect of protease inhibitors on the intracellular production of free radicals was investigated by measuring chemiluminescence (CL) elicited from phagocytosed luminol-bound microspheres (Lumispheres) in human neutrophils stimulated with formylmethionyl-leucyl-phenylalanine (fMLP), interleukin-8 (IL-8), phorbol 12-myristate 13-acetate, or diacylglycerol. Both gabexate mesylate (Foy) and ulinastatin (Miraclid), urinary trypsin inhibitor, increased intracellular CL in a dose dependent manner. Compared to control buffer without protease inhibitor, gabexate mesylate (322 micrograms/ml) caused about a 10-fold increase in intracellular CL in stimulated neutrophils, and ulinastatin (3100 U/ml) a twofold increase in neutrophils stimulated with fMLP or IL-8. When the protease inhibitors were added to the cell suspension after the phagocytosis of lumispheres, CL responses rapidly increased again to the level which was observed when both protease inhibitors and neutrophil stimulants were incubated simultaneously. In contrast, extracellular release of oxygen metabolites from stimulated neutrophils, assayed by a conventional measurement of luminol-dependent CL, was reduced by the protease inhibitors in a dose dependent fashion. When luminol-unbound microspheres were incubated with neutrophils stimulated by fMLP in luminol solution, extracellular CL was almost completely inhibited by gabexate mesylate. These results indicate that the protease inhibitors enhance the generation of intracellular CL and suppress the extracellular release of free radicals.

Dose-Response Relationship, Drug↗
PubMed1992

Pharmacokinetic profile of glycyrrhizin in healthy volunteers by a new high-performance liquid chromatographic method.

An improved high-performance liquid chromatographic method was developed for the quantification of glycyrrhizin and its metabolites in human plasma. The improved method was selective and made it possible to determine precisely glycyrrhizin at levels as low as 500 ng/mL. The pharmacokinetic behavior of glycyrrhizin and its metabolites after oral and intravenous administration of glycyrrhizin to normal subjects was investigated. After oral administration of glycyrrhizin (100 mg) to three normal subjects, the major metabolite of glycyrrhizin (glycyrrhetic acid) appeared in plasma (less than 200 ng/mL), but glycyrrhizin was not found. On the other hand, glycyrrhizin was found in urine, and the amount excreted was 1.1-2.5% of the dose. This finding suggests that glycyrrhizin is partly absorbed in the intact form from the gastrointestinal tract. The concentration of glycyrrhizin in plasma after intravenous administration of glycyrrhizin (40, 80, and 120 mg) showed biexponential profiles during the 24-h period after administration of each dose. The glycyrrhizin metabolites, glycyrrhetic acid and glycyrrhetic acid-3-O-glucuronide, were not detected in either plasma or urine. The terminal half-life of glycyrrhizin, the apparent volume of the central compartment, the steady-state distribution volume, and the total body clearance in three dosing experiments were 2.7-4.8 h, 37-64 mL/kg, 59-98 mL/kg, and 16-25 mL/kg/h, respectively. Glycyrrhizin was not detected in plasma after oral administration of the usual therapeutic dose of glycyrrhizin, and no dose dependency of the drug was observed in the dose range of 40-120 mg.

Administration, Oral↗
PubMed1992

Regulation of G418 selection efficiency by cell-cell interaction in transfection.

We attempted to establish the optimum conditions for the calcium phosphate (CaPO4) precipitation protocol by counting G418 resistant (G418r) colonies after transfection of pSV2-neo DNA into BALB 3T3 cells. The amount and molecular size of carrier DNA, number of plating cells, treatment period of DNA-CaPO4 precipitates and expression time of G418 selection were found to be important factors in the induction of G418r colonies. Six G418r clones were derived from BALB 3T3, NIH 3T3 and FRSK cells, and cocultured with G418 sensitive (G418s) parent cells in G418 medium. The colony formation capacity of all G418r cell clones decreased with the increasing number of plated G418s cells. Cell-cell contact appeared to be necessary to reduce the colony formation of G418r cells, and contact-dependent G418r cell killing was probably not related to gap junction formation. Contact-mediated cell killing is a likely explanation for the observation that induction of G418r colonies is often reduced under conditions of high-density plating, long treatment of DNA-CaPO4 precipitates, and long expression time of G418 selection. These results suggest that in some instances transfection efficiency using pSV2-neo DNA should be carefully evaluated because culture conditions can mask the induction of G418r colonies.

Animals↗
PubMed1992

Malignant melanomas of the oral cavity: heterogeneity of pathological and clinical features.

Data on 35 patients with oral malignant melanomas were pooled and the pathological features and the clinical course were examined in detail. Of these 35 cases, 27 (77.1%) showed a two-phase growth pattern, with both a vertical and a radial growth phase. Moreover, these 27 cases were classified into three subtypes according to gross features of the vertical growth phase; nodular, flat elevated and ulcerated types. Almost two-thirds of the cases were of the melanotic type. Malignant melanomas without a radial growth phase were found in 8 instances, all of which showed a nodular growth pattern, 1 being of melanotic type and 7 amelanotic. Mean latent insidious periods were evaluated for the cases with different growth phases. Cases with a radical growth phase exhibited the longest mean latent period (35.7 months), and a median survival time of 23.5 months. Cases without a radial growth phase showed a short mean latent period (2.1 months), and a median survival time of 7.5 months. The thickness of invasion ranged from 2 to 9 mm. Although 77.1% of the cases depicted similar pathological patterns to acral lentiginous melanomas of the skin, oral malignant melanomas demonstrated heterogeneity in morphological features, developmental process and biological behaviour. The histogenesis of oral melanomas is briefly discussed.

Adult↗
PubMed1992

Bowel preparation for the total colonoscopy by 2,000 ml of balanced lavage solution (Golytely) and sennoside.

One of disadvantages of the Golytely preparation is that examinees have to drink as much as 4,000 ml of Golytely. To overcome this disadvantage, we designed a modified preparation regimen in which examinees have to drink only 2,000 ml of Golytely by taking sennoside orally. Bowel preparation was carried out in 297 examinees by this modified method. Examinees ate their usual diet and took 36 mg of sennoside orally on the night before the examination. On the day of the examination, the examinees drank a total of 2,000 ml of Golytely. No severe complications were noted and 97% of the examinees were able to drink the dose of 2,000 ml. Subjects who had also experienced bowel preparation by the modified method of Brown were asked to compare the two regimens, and only 1% preferred Brown's method while 73% preferred bowel preparation by our Golytely method. The result of bowel preparation by this method was excellent or good in 90 to 97% of the subjects at all sites in the colon and rectum. We conclude that bowel preparation for total colonoscopy using 2,000 ml of Golytely and sennoside is superior because it is highly acceptable to the examinees and provides excellent gut irrigation.

Adolescent↗