Search PubMed⌕ Search

Biomedical subjects

K Fukuda

Publications and source records attributed to K Fukuda.

At least 649 records · Page 36Linked to original sources
PubMed1991

Structural alterations in fibronectins secreted from 4 human hepatoma cell lines: demonstration of hepatoma-associated alternative splicing of mRNA precursors.

The synthesis and secretion of fibronectin (FN) was observed in 4 human hepatocellular carcinoma (HCC)-derived cell lines using a serum-free conditioned medium. It was also demonstrated that FNs secreted from these cell lines (HCC-FN) were structurally altered compared to plasma FN produced by normal hepatocytes. Using limited proteolysis with cathepsin D followed by immunoblot analysis with a carboxy-terminal specific antibody, the existence of an extra domain (ED) segment in the carboxy-terminal region of HCC-FNs was confirmed. Expression of the additional nucleotide insert (ED sequence), which is reported to be absent in hepatocyte mRNA and is characteristic of cellular FN-mRNA, was confirmed in mRNA from all 4 HCC cell lines. It is now evident that HCC cells secrete different variants of FN compared with normal hepatocytes due to alternative splicing of mRNA precursors. This differential RNA processing seems to be one of the phenotypic alterations associated with the oncogenic transformation of hepatocytes.

Carcinoma, Hepatocellular↗
PubMed1991

Reproducibility of reports of past history, smoking, drinking and dietary habits obtained by a personal interview for a case-control study on liver cirrhosis and hepatocellular carcinoma.

The reproducibility of responses on life style measurements observed during a personal interview was assessed by a test-retest method. Fifty-one apparently healthy male subjects were interviewed twice, mostly within a 10 week interval. Responses on past history, smoking and drinking habits yielded relatively high intraclass correlation coefficients between the two interviews, as compared to the responses on dietary habits for the previous 1 to 2 years, which varied depending on the food items.

Adult↗
PubMed1991

[A case of metastatic rib tumor from thyroid cancer confirmed by the presence of thyroglobulin].

A 63-year-old female, with a chief complaint of right chest pain was referred to our hospital because of an abnormal right chest wall shadow on chest X-ray. A rib tumor was suspected based on her chest CT scan. Percutaneous needle biopsy yielded a diagnosis of well-differentiated adenocarcinoma. As metastatic rib tumor was suspected, the primary tumor was sought for. A thyroid gland nodule was recognized by ultrasonography, and the cytological diagnosis was class V. Immunohistological demonstration of the thyroglobulin studies of the rib tumor tissue revealed papillary and trabecular patterns of cell arrangement and the presence of thyroglobulin existence. Definitive diagnosis of metastatic rib tumor from thyroid cancer was established. Immunohistological examination is useful to confirm the diagnosis of metastatic cancer of thyroid origin.

Adenocarcinoma↗
PubMed1991

[A case of leiomyoma of the trachea].

An asymptomatic 59-year-old male in whom an abnormal shadow was detected on indirect chest X-ray film, was referred to our hospital for further examination. Further examinations revealed no problem at the previously checked site. However, bronchoscopy revealed a protruding hemispheric lesion on the membranous portion of the trachea 2 cm above the carina. The biopsy specimens revealed that the lesion was leiomyoma of the trachea. Transbronchoscopic biopsy was performed three times and the lesion disappeared. A few small fibrous nodules remained. The incidence of this primary tracheal tumor is rare, and benign lesions are much less common than malignant lesions. Furthermore, leiomyoma of the trachea is extremely rare. Only 20 cases have been reported in Japanese and English literature. The average age of the reported cases, including our case, was 49.3 years old. Among the male patients, most cases were around 50 years old but among female patients, there was no standard age for this disease. Clinical symptoms included coughing, dyspnea, wheezing and bloody sputum. There were several patients with severe dyspnea, two of which died. Ten patients (50%) had been misdiagnosed as having bronchial asthma. If a case is suspected to be bronchial asthma in which and where bronchodilators have little effect, we must always consider the possibility of this type of lesion, and perform further examinations and treatment.

Bronchoscopy↗
PubMed1991

[Vena caval flow patterns in patients with constrictive pericarditis: analysis by catheter-tip Doppler flowmetry].

Changes in superior and inferior vena caval flow patterns were analyzed in 5 patients with constrictive pericarditis and were compared with those of 10 normal control subjects. Caval flows were measured using catheter-tip Doppler flowmeters. The normal controls showed biphasic M-shaped flow patterns; the peaks of the first forward flow (S wave) and of the second forward flow (D wave) appeared coincident with mid-systole and mid-diastole, respectively. Reverse flows fell during the atrial contraction period (A wave) and late systole (V wave). In the normal controls, the ratios of the S wave to the D wave (S/D ratio) and the A wave to the S wave (A/S ratio) were 2.15 +/- 0.41 and 0.18 +/- 0.10, respectively, and there was a disproportionate respiratory variation in the S and D waves in the normal controls. In constrictive pericarditis, superior and inferior vena caval flow velocities were lower than those in the normal controls. The S/D and A/S ratios were 1.46 +/- 0.27 (p < 0.05 vs control) and 0.66 +/- 0.15 (p < 0.01 vs control), respectively, with the A wave increasing in proportion to the severity of constrictive pericarditis. In addition, there was only a minimal respiratory variation in constrictive pericarditis. In conclusion, recognition of the patterns of the superior and inferior vena caval flow velocities may be useful for diagnosing constrictive pericarditis.

Adult↗
PubMed1991

The cell content of peritoneal exudates following the injection of neutral thiol protease into guinea pigs.

The cell content of the peritoneal exudate was examined 4 days after an intraperitoneal injection of glycogen in uninfected and Paragonimus westermani-infected guinea pigs. In uninfected animals a reduction in macrophage count and an accumulation of granulocytes in the exudate were observed at 3 and 6 hr after an intraperitoneal injection of purified neutral thiol protease from P. westermani metacercariae. No such effect occurred after the enzyme was injected into infected animals. At 9 hr after enzyme injection, vacuoles were found in the cytoplasm of macrophages in uninfected animals.

Animals↗
PubMed1991

Immunohistochemical study of deposits on intraocular lenses explanted from human eyes.

Immunohistochemical studies of deposits were carried out on two intraocular lenses (IOLs) explanted from human eyes. One anterior chamber intraocular lens (AC-IOL) was studied using a monoclonal anti-human type I collagen-peptide antibody (C-Ab). One posterior chamber intraocular lens (PC-IOL) was studied using a monoclonal anti-human vimentin antibody (V-Ab). Most of the cells on the AC-IOL contained many melanin granules in the cytoplasm and were thought to be macrophages. They did not show any immunoreactivity to C-Ab. Some spindle-shaped cells and fibrous deposits at the margin of the lens optics showed immunoreactivity to the antibody. These cells were thought to be fibroblasts migrating from the tissue around the IOL, such as the iris. On the PC-IOL, many mononuclear cells and multinucleated giant cells were observed. These cells showed immunoreactivity to vimentin and contained immunostained fibers which were intermediate filaments. They were thought to be either of mesodermal origin or derived from the lens epithelium.

Aged↗
PubMed1991

Transport of cyclosporin A in kidney epithelial cell line (LLC-PK1).

The characteristics of cyclosporin A transport have been studied in cultured kidney epithelial cell line LLC-PK1. The uptake of cyclosporin A by LLC-PK1 cells was time-dependent and reached a steady state at about 30 min. The initial uptake was saturable and was inhibited by cyclosporin A analogs, cyclosporin C and D and by verapamil, but not by metabolic inhibitors such as 2,4-dinitrophenol and rotenone. Cyclosporin A uptake as well as efflux was strongly dependent on temperature. The Arrhenius plot for cyclosporin A uptake was biphasic, whereas the Arrhenius plot for sulfanilamide uptake, which is transported by a simple diffusion, was linear. These results indicate that a specific mechanism is concerned in the transport of cyclosporin A in LLC-PK1, cells.

Animals↗
PubMed1991

Selective increase in cytochrome P450 content in hepatic microsomes from rats with ventromedial hypothalamic lesions.

Changes in the components of hepatic microsomal electron transport systems and in drug hydroxylase activities were investigated in ventromedial hypothalamus (VMH) lesioned obese rats. Eight weeks after electrolysis of the bilateral VMH, the content of cytochrome P450 per mg microsomal protein (0.79 +/- 0.07 nmol/mg protein) was significantly higher (P less than 0.02) than that in the sham-operated rats (0.59 +/- 0.02). Cytochrome P450 per whole liver in the VMH-lesioned obese rats had also significantly increased (87 +/- 9 nmol vs 56 +/- 3, P less than 0.02). No significant differences were found in the cytochrome b5 contents, and the activities of NADPH- and NADH-cytochrome c reductases between the VMH-lesioned obese and sham-operated rats. The demethylation activities of aminopyrine (1.04 +/- 0.02 nmol/mg protein/min vs 0.94 +/- 0.02, P less than 0.05) and p-nitroanisole (0.96 +/- 0.02 vs 0.89 +/- 0.02 , p less than 0.02) and the aniline hydroxylase activity (0.22 +/- 0.01 vs 0.16 +/- 0.01, P less than 0.01) were enhanced, but 7-ethoxycoumarin O-deethylase activity was unchanged in the VMH-lesioned obese rats. These results indicate a selective increase in the content of cytochrome P450 among the components of the P450-dependent mixed function oxidase system in the liver of VMH-lesioned obese rats. Our observations suggest that drug metabolism may be enhanced in the hypothalamic obesity.

Animals↗
PubMed1991

[Early diagnosis of acute myocardial infarction by an immunoinhibition method for analysis of creatine kinase isoforms].

Conventional isoenzyme and enzyme values in serum usually are normal during the first few hours of acute myocardial infarction (AMI). Thus definitive diagnosis may be delayed. Measurement of serum creatine kinase (CK) isoform has begun to attract attention. In this study, we measured CK isoform with an immunoinhibition method in the first available samples from patients with AMI and from healthy subjects. In the 394 healthy subjects, the mean ratio of MM3 to MM1 of CK isoform was 0.494 +/- 0.1495 (SD). The upper limit of the reference values for this ratio was considered to be 0.793 (mean + 2 SD). In 40 of 48 patients, this ratio in the first available samples from patients with AMI was greater than 0.793. In 15 of 20 patients whose total CK activity was less than 260 IU/l, this ratio was greater than 0.793, while CK-MB activity measured with the immunoinhibition method was well within the reference range in all of these patients. Our results show that in the first available samples from patients with AMI, measurement of the ratio of MM3 to MM1 of CK isoform has the highest diagnostic efficiency. Thus, measurement of CK isoform with the immunoinhibition method can be applied for early diagnosis of AMI.

Creatine Kinase↗
PubMed1991

[A case report of Creutzfeldt-Jakob disease associated with myocarditis].

We have encountered a case of Creutzfeldt-Jakob disease associated with myocarditis. A 77 year-old woman was admitted to a hospital with complaints of rapidly progressive visual disturbance, myoclonus and dementia. Electroencephalogram revealed a periodic synchronous discharge and Creutzfeldt-Jakob disease was suspected. Then she moved to our hospital, because acute myocarditis was combined with ST-T changes on electrocardiogram, and generalized hypokinetic motion of the left ventricle on echocardiogram. The abnormal findings in electrocardiography and echocardiography were transient. Blood levels of enzymes derived from the myocardium were slightly elevated. We could not find a distinct increase in the titer of neutralizing antibody to various viruses. In this case, the cause of myocarditis may have been associated with the infectious agent of Creutzfeldt-Jakob disease. This report might be the first one with a case of Creutzfeldt-Jakob disease complicated with myocarditis.

Aged↗
PubMed1990

Selective coupling of different muscarinic acetylcholine receptors to neuronal calcium currents in DNA-transfected cells.

Acetylcholine (ACh) can inhibit calcium currents (ICa) in nerve cells by activating muscarinic ACh receptors (mAChR). There are several different genetic subtypes of mAChR. It is not known which subtype(s) are responsible for ICa inhibition. To resolve this issue, we measured ICa inhibition by ACh with patch-clamp recording, by using Ba2+ as charge carrier, in clones of NG108-15 neuroblastoma x glioma hybrid cells transfected with DNA for mAChRI, II, III and IV. Control (non-transfected) cells showed a mean maximum inhibition of peak ICa of 12.8 +/- 1.8% (n = 36) at 1 mM ACh. No consistent increase in inhibition was detected in vector-transfected cells, or in cells transformed to express mAChRI or mAChRIII. In contrast, inhibition was significantly increased in clones transformed to express mAChRII or mAChRIV. Inhibition was not correlated with the number of muscarinic receptors as determined by 3H-quinuclidinyl benzilate binding. Inhibition in both control and transfected cells was prevented by pretreatment with pertussis toxin (PTx). Inhibition persisted in the presence of extracellular or intracellular dibutyryl cyclic AMP, and hence is not because of inhibition of adenylate cyclase. We conclude that the inhibition of neuronal ICa is mediated preferentially by mAChRII and mAChRIV, via a PTx-sensitive GTP-binding protein.

Acetylcholine↗
PubMed1990

Effect of a light-induced pH gradient on purple-to-blue and purple-to-red transitions of bacteriorhodopsin.

Bacteriorhodopsin-containing vesicles that were able to alkalize the extravesicular medium by greater than 1.5 pH units under illumination, i.e., inside-out vesicles, were reconstituted by reverse-phase evaporation with Halobacterium halobium polar lipids or exogenous phospholipids. Acid titration of a dark-adapted sample was accompanied by a color change from purple to blue (pKa = 2.5-4.5 in 0.15 M K2SO4), and alkali titration resulted in the formation of a red species absorbing maximally at 480 nm (pKa = 7 to greater than 9), the pKa values and the extents of these color changes being dependent on the nature of lipid. When a vesicle suspension at neutral or weakly acidic pH was irradiated by continuous light so that a large pH gradient was generated across the membrane, either a purple-to-blue or a purple-to-red transition took place. The light-induced purple-to-red transition was significant in an unbuffered vesicle suspension and correlated with the pH change in the extravesicular medium. The result suggests that the purple-to-red transition is driven from the extravesicular side, i.e., from the C-terminal membrane surface. In the presence of buffer molecules outside, the dominant color change induced in the light was the purple-to-blue transition, which seemed to be due to a large decrease in the intravesicular pH. But an apparently inconsistent result was obtained when the extravesicular medium was acidified by a HCl pulse, which was accompanied by a rapid color change to blue. We arrived at the following explanation: The two bR isomers, one containing all-trans-retinal and the other 13-cis-retinal, respond differently to pH changes in the extravesicular and the intravesicular medium. In this relation, full light adaptation was not achieved when the light-induced purple-to-blue transition was significant; i.e., only the 13-cis isomer is likely to respond to a pH change at the N-terminal membrane surface.

Bacteriorhodopsins↗
PubMed1990

[The clinical significance of serum sialyl SSEA-1 antigen in obstetrical and gynecological patients].

To evaluate the clinical significance of serum SSEA-1 level, the antigen level was measured in sera of obstetric and gynecologic patients. A positive rate was low in patients with endometriosis (9.1%), myoma uteri (0%), benign ovarian tumor (15%), cervical squamous cell carcinoma (14%) and endometrial carcinoma (18%). In this series of study, interest was that positive cases in benign ovarian tumor group were all patients with dermoid cyst. On the other hand, a high positive rate was observed among the patients with cervical adenocarcinoma (50%), primary ovarian malignancies (55%) and secondary ovarian malignancies (50%). Among the patients with ovarian malignancies, serum sialyl SSEA-1 level significantly increased according to clinical stage. In patients with positive serum sialyl SSEA-1, rising or falling of the serum level of this antigen correlated well with progression or regression of the disease. Measurement of serum CA125 was also performed in patients with ovarian malignancies, which showed a significantly higher positive rate (96%) and revealed that this antigen has no correlation with sialyl SSEA-1. A low positive rate of serum sialyl SSEA-1 level (9.1%) was observed in gravidas, while a higher positive rate (43%) in puerperas, especially within three days after parturition. This evidence should be considered when serum sialyl SSEA-1 antigen is measured as tumor marker. All these observations suggest that the measurement of serum sialyl SSEA-1 level is useful not only in the diagnosis of ovarian malignancies but for the judgment of the effect of treatment and the search for their recurrences.

Antigens, Neoplasm↗
PubMed1990

The appearance of hepatoma-associated chromosomal non-histone proteins in rat liver after a single dose of 3'-MDAB followed by treatment of phenobarbital.

Previously we have described polyclonal antibodies that recognized a group of nuclear nonhistone proteins whose molecular weights ranged in size from 170 to 220 kDa. These antigenic nonhistone chromosomal proteins are abundant in rat hepatoma chromatin. In this report we discuss the synthesis and cellular localization of these particular proteins during the multistage process of hepatocarcinogenesis. The appearance of these antigenic proteins in rat liver nuclei approximately parallels the appearance of alpha-fetoprotein in the cytosol of hepatocytes. However, the immunoreactivity of antigenic proteins increased steadily even during the prominent dip in the AFP concentration between 50 and 100 days of carcinogenesis. The effect of the tumor promoting agent, phenobarbital, on the synthesis of antigenic nuclear proteins was also studied. The appearance of hepatoma-associated non-histone chromosomal proteins at early stages of tumor promotion during hepatocarcinogenesis was observed. The results of these studies demonstrate that the hepatoma-associated non-histone proteins are expressed not only in hepatoma cells, but also in hepatocyte cells committed to carcinogenesis.

Animals↗
PubMed1990

Quantitation of C4 nephritic factor by an enzyme-linked immunosorbent assay.

We have developed an enzyme-linked immunosorbent assay (ELISA) for the quantitation of C4 nephritic factor (C4NeF). Incubation of the C4NeF-positive serum from patient M.I. with normal human serum (NHS) in the presence of human aggregated IgG (AHG) resulted in the formation of stable C4-C2 complex. No complex was formed in EDTA or under the condition free of AHG. The reaction mixture was filtered through an ACA 22 column, from which the C4-C2 complex was eluted at the first protein peak. When IgG purified from M.I. serum was incubated with NHS and AHG, C4-C2 complex also increased in proportion to dose of the purified M.I. IgG. These results show that C4NeF in M.I. serum stabilizes C4b2a convertase of the classical complement pathway, and is quantified by the ELISA. C4NeF activity was measured, using the ELISA method, in patients with various glomerular diseases, and found elevated in three of 24 patients with membranoproliferative glomerulonephritis (MPGN) type I and slightly but distinctly positive in seven of 24. No C4NeF was detected in two C3 nephritic factor-positive patients with MPGN type II and six with active systemic lupus erythematosus. The new method was more simple and quantitative than C4b2a stabilization assay for C4NeF.

Animals↗