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Biomedical subjects

K Fukuda

Publications and source records attributed to K Fukuda.

At least 541 records · Page 30Linked to original sources

[CT findings of pulmonary sarcoidosis].

A retrospective review was performed on CT findings in 46 patients of pulmonary sarcoidosis proven by histology. Pulmonary lesions were detected in 26 patients (56.5%). Frequent CT findings were peribronchial markings (69.2%), diffuse small nodules (65.4%), pleural lesions (38.5%), lymphangitis carcinomatosa like changes (30.8%), and large irregular nodules (30.8%). Follow up CTs were obtained in 18 patients. Peribronchial markings and diffuse small nodules had tendency to improve, although atelectasis, pleural thickening, and bullae were irreversible and progressive. CT plays an important role in the diagnosis and have a prognostic value in pulmonary sarcoidosis.

Adult↗

Characteristics of bone marrow cells of patients with eosinophilic pneumonia.

Bone marrow features were studied to clarify the pathogenesis of peripheral blood eosinophilia in eosinophilic pneumonia. We observed (1) increases in the number of nucleated cells in patients with this disease as compared with that of control subjects (205,944 +/- 104,253 versus 118,154 +/- 76,306) (P < .05); (2) increases in the myelocyte to erythrocyte ratio (6.95 +/- 4.06 versus 4.02 +/- 1.36) (P < .05) mainly due to a marked increase in the eosinophilic series; and (3) an increase in the eosinophilic series with advance in the maturation process, the degree of increase becoming greater with the increase in eosinophilic maturation. These findings suggest that differentiation and maturation of the precursor cells into mature eosinophils were accelerated in the bone marrow in eosinophilic pneumonia by some lymphokines as eosinophilopoietic growth factors.

Adult↗

[Microsurgical anatomy of the anterior communicating artery and its perforating arteries important for interhemispheric trans-lamina terminalis approach: analysis based on cadaver brains].

Microsurgical anatomy of anterior communicating artery (ACoA) and its perforating arteries important for interhemispheric trans-lamina terminalis approach is examined in 25 cadaver brains under magnification using a surgical microscope. ACoA were found in all cases but 60% of those cases had variations such as plexiform ACoA, dimple ACoA, fenestrated ACoA, triple A2 and azygous ACA. In cases with variations such as plexiform ACoA, triple A2 and azygous ACA, it seems difficult to section and divide the ACoA to obtain a better operative field. Perforating arteries of ACoA were noted in all cases. They were classified into the subcallosal artery, hypothalamic artery and chiasmatic artery according to caliber, origin, course and termination. Among these three arteries, subcallosal artery is thought to be an offending artery in memory impairment, character change and psychological abnormalities, because it terminates at the bilateral subcallosal areas. We stress in this paper that the subcallosal artery is the most important perforating artery of ACoA and the incidence of variations of ACoA is higher than previously reported.

Aged↗

cDNA cloning and pharmacological characterization of an opioid receptor with high affinities for kappa-subtype-selective ligands.

The amino acid sequence of a rat opioid receptor, designated as ROR-D, has been deduced by cloning and sequencing the cDNA. The ROR-D expressed from the cDNA exhibits high affinities for ligands selective for the opioid receptor kappa-subtype and low affinities for ligands selective for the delta- and mu-subtypes. RNA blot hybridization analysis indicated that ROR-D mRNA is distributed in cerebrum and brainstem but not in cerebellum.

Amino Acid Sequence↗

Primary structures and expression from cDNAs of rat opioid receptor delta- and mu-subtypes.

The complete amino acid sequences of rat opioid receptors (designated as ROR-A and ROR-B) have been deduced by cloning and sequencing the cDNAs. The ligand-binding properties of ROR-A and ROR-B expressed from the cloned cDNAs in Chinese hamster ovary cells correspond most closely to those of the pharmacologically defined delta- and mu-opioid receptor subtypes, respectively. RNA blot hybridization analysis revealed that cerebrum and brainstem contain both ROR-A and ROR-B mRNAs, whereas neither ROR-A nor ROR-B mRNAs can be detected in cerebellum.

Amino Acid Sequence↗

Coupling of m2 and m4 muscarinic acetylcholine receptor subtypes to Ca(2+)-dependent K+ channels in transformed NL308 neuroblastoma x fibroblast hybrid cells.

Muscarinic acetylcholine receptor (mAChR) subtype (m1-m4)-specific cDNAs were transfected into NL308 neuroblastoma-fibroblast hybrid cells and clones expressing each of the individual mAChR subtypes m1, m2, m3 and m4 obtained. Acetylcholine increased phosphoinositide (PI) turnover in m1- and m3-transformed cells, but did not produce detectable changes in m2- and m4-transformed cells. In cells expressing m1 and m3 subtypes, ACh produced an initial outward K+ current, followed by a cationic current. In cells expressing m2 and m4 receptors, only the initial K+ current was detected. The outward currents were associated with a rise in intracellular Ca2+ as measured with Fura-2 or Indo-1, and were inhibited by chelating intracellular Ca2+ with external BAPTA-AM, or by external charybdotoxin or Ba2+: hence they were attributed to the activation of a Ca(2+)-dependent K+ current. However, the outward current produced in m2- and m4-transformed cells was blocked by pretreatment with 5 ng ml-1 Pertussis toxin (PTX), whereas that in m1- and m3-transformed cells was not. These results suggest that m2- and m4-receptors in transformed NL308 cells coupled to PTX-sensitive G-protein which is capable of mobilizing intracellular Ca2+ and activate IK(Ca), whereas m1 and m3 receptors activate a similar process through a different, PTX-insensitive G-protein.

Acetylcholine↗

Association of alcohol intake, cigarette smoking, and occupational status with the risk of idiopathic osteonecrosis of the femoral head.

To investigate the association of alcohol intake, cigarette smoking, occupation, and other factors with the development of idiopathic osteonecrosis of the femoral head, a nationwide multicenter case-control study was conducted in Japan during 1988-1990, comparing 118 cases with no history of systemic corticosteroid use with 236 controls matched for sex, age, ethnicity, clinic, and date of initial examination. The risks of developing femoral head necrosis associated with potential risk factors were estimated by adjusted relative odds obtained by a conditional logistic regression model. The elevated relative odds were observed for occasional drinkers (relative odds = 3.2, 95% confidence interval 1.1-9.2) and regular drinkers (relative odds = 13.1, 95% confidence interval 4.1-42.5) with a significant dose-response relation (p < 0.001). For current drinkers, the relative odds were 2.8, 9.4, and 14.8 for < 320, 320-799, and > or = 800 g/week of ethanol intake, respectively. An increased risk was found for current smokers (relative odds = 4.7, 95% confidence interval 1.5-14.5), but a linear increasing trend in the cumulative effect of smoking was not evident at 20 pack-years or over. A weak but significant dose-response relation was observed for daily occupational energy consumption (p < 0.05). The present study confirmed the strong association of alcohol intake and positive association of cigarette smoking and suggested the role of heavy physical work.

Adult↗

Levels of circulating tumor necrosis factor alpha and interleukin-6 in patients with rheumatoid arthritis. Relationship to serum levels of hyaluronan and antigenic keratan sulfate.

OBJECTIVE: To measure serum levels of tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) in patients with rheumatoid arthritis (RA) and age-matched control subjects and to study how these correlate with serum levels of hyaluronan (HA) and antigenic keratan sulfate (KS) and other biochemical as well as clinical indicators of disease activity. METHODS: Immunoassays were used to measure levels of TNF alpha, IL-6, HA, and antigenic KS in the serum of 35 patients with RA and a group of age- and sex-matched control subjects. Clinical disease activity in the RA group was assessed using the Lansbury index. Drug intake was recorded and the erythrocyte sedimentation rate, and levels of fibrinogen, creatinine, bilirubin, alkaline phosphatase, lactate dehydrogenase, and aminotransferase were measured. RESULTS: Serum levels of TNF alpha, IL-6, and HA were significantly higher in the RA population than in the control group. In patients with RA, serum levels of HA correlated positively with serum levels of TNF alpha and with clinical joint scores, but only weakly with other laboratory parameters of inflammation. Serum levels of antigenic KS correlated negatively with levels of circulating TNF alpha, but much more weakly with other clinical and biochemical parameters of disease activity. CONCLUSION: These in vivo data support in vitro studies which have shown that TNF alpha is a potent stimulator of HA synthesis by synovial lining cells. The results strengthen the contention that serum HA may be a unique marker of synovial involvement and inflammation, rather than of only inflammation, in RA.

Adult↗

Induction of apoptosis by transforming growth factor-beta 1 in the rat hepatoma cell line McA-RH7777: a possible association with tissue transglutaminase expression.

We report here that transforming growth factor-beta 1 induces cell death in the Morris hepatoma cell line McA-RH7777. We assessed the type of cell death induced by transforming growth factor-beta 1 in this hepatoma cell line on the basis of morphological and biochemical characteristics. Dying cells, which detached from the cell monolayer, showed morphological characteristics of apoptosis (programmed cell death) such as chromatin condensation, nuclear disintegration and cellular fragmentation into clusters of eosinophilic globules. DNA isolated from these cells showed a ladder pattern consisting of multimers of 180 to 190 bp, indicating extensive DNA cleavage into oligonucleosomal units by an endogenous endonuclease. Treatment of the dead cells with detergents and chaotropic agents resulted in formation of insoluble shells, so-called apoptotic bodies, suggesting extensive cross-linking of cell proteins by tissue transglutaminase. Furthermore, increased amounts of cytosolic tissue transglutaminase, which has been recognized as a possible marker of apoptosis, and extensive cross-linking of cytokeratin polypeptides was demonstrated in TGF-beta 1-treated hepatoma cells on immunoblot analysis. These results provide strong evidence that the cell death induced by TGF-beta 1 in McA-RH7777 hepatoma cells is mainly apoptotic. It also suggests that a specific induction of the cytosolic tissue transglutaminase may be involved in the TGF-beta 1-induced pathways of apoptotic cell death in McA-RH7777 hepatoma cells.

Animals↗

A single EGF-like motif of laminin is responsible for high affinity nidogen binding.

A major nidogen binding site of mouse laminin was previously localized to about three EGF-like repeats (Nos 3-5) of its B2 chain domain III [M. Gerl et al. (1991) Eur. J. Biochem., 202, 167]. The corresponding cDNA was amplified by polymerase chain reaction and inserted into a eukaryotic expression vector tagged with a signal peptide. Stably transfected human kidney cell clones were shown to process and secrete the resulting fragment B2III3-5 in substantial quantities. It possessed high binding activity for recombinant nidogen in ligand assays, with an affinity comparable with that of authentic laminin fragments. In addition, complexes of B2III3-5 and nidogen could be efficiently converted into a covalent complex by cross-linking reagents. Proteolytic degradation of the covalent complex demonstrated the association of B2III3-5 with a approximately 80 residue segment of nidogen domain G3 to which laminin binding has previously been attributed. The correct formation of most of the 12 disulfide bridges in B2III3-5 was indicated from its protease resistance and the complete loss of cross-reacting epitopes as well as of nidogen-binding activity after reduction and alkylation. Smaller fragments were prepared by the same recombinant procedure and showed that combinations of EGF-like repeats 3-4 and 4-5 and the single repeat 4 but not repeats 3 or 5 possess full nidogen-binding activity. This identifies repeat 4 as the only binding structure. The sequence of repeat 4 is well conserved in the human and in part in the Drosophila laminin B2 chain.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

Correlation between HPV positivity and state of the p53 gene in cervical carcinoma cell lines.

Human papillomavirus (HPV) infection is clearly associated with cervical carcinomas, yet it is also true that there are cervical carcinomas in which HPV DNA is absent. We examined eight established cell lines derived from cervical carcinomas for the presence of mutations of the p53 antioncogene in relation to the presence of HPV DNA sequences. Of these eight cell lines, seven were positive for HPV DNA and the remaining one was negative for HPV DNA. Single-strand conformation polymorphism analyses revealed a point mutation of the p53 gene in the cell line in which HPV DNA was absent. Sequencing analysis revealed a single-base mutation at codon 273 from CGT to CAT(Arg-->His) and immunocytochemical studies provided evidence that the p53 protein was overexpressed in this cell line. Our observations suggest that the loss of normal p53 gene function may be linked to the oncogenesis of cervical carcinoma.

Adenocarcinoma↗

Long-term therapeutic efficacy of interferon for patients with chronic hepatitis C.

Interferon is being used for therapy of chronic hepatitis C, but its long-term results have not been reported. We studied 65 patients with this disease who were monitored for at least 2 years after completion of the therapy. Almost all patients who had responded to therapy at 6 months after the end of therapy had normal levels of alanine aminotransferase (ALT) when evaluated later. The level of ALT became normal for the first time in some patients more than 6 months after therapy ended. The level of ALT in many of the patients without HCV RNA had become normal 6 months after the end of the therapy. One of three schedules was employed: three times weekly long-term; daily for two weeks and none for two weeks in a cycle; and daily for several weeks; 57%, 29%, and 17% of the patients on these schedules came to have normal ALT levels. Patients without HCV RNA at six months after completion of therapy tended to have higher responses in terms an increased level of 2',5'-oligoadenylate synthetase of mononuclear cells in vitro before therapy began. However, therapy three times per week was effective even for some patients judged not responsive to IFN by this test. The results showed that IFN therapy was effective for chronic hepatitis C when judged by long-term results.

Adult↗

A tumor-associated 120 kDa nuclear protein: characterization using a monoclonal antibody and a partial cDNA clone.

1. We have established a murine hybridoma (F86) that secretes a monoclonal antibody (MoAb) specific for a 120 kDa nuclear protein (p120). p120 is expressed in all human cell lines investigated, whether of tumor or normal cell origin. 2. However, expression of p120 is significantly higher in neoplastic cells than in normal cells. The amount of p120 is relatively constant through the cell cycle and does not appear to be modulated by 72 hr serum starvation. 3. These results suggest that p120 plays some role in nuclear events associated with neoplastic phenotypes rather than in cell proliferation. 4. In situ immunofluorescence analyses indicate that p120 is located exclusively in nuclei of interphase cells. It is not present in nucleoli. 5. During mitosis, p120 is distributed in the cytoplasm and is not associated with condensed chromosomes which, together with RNAse experiments, suggests that it may be associated with hnRNA or hnRNP particles. 6. Western blot analyses indicate that p120 consists of two molecular weight forms which differ by 2-3 kDa in reduced SDS-PAGE, and several isoelectric variants in the acidic range. 7. Fractionation studies indicate that p120 has accessible free sulfhydryl group(s) and can bind ssDNA and heparin. 8. A partial cDNA clone, encoding the carboxyl terminus of p120, was isolated from a lambda gt11 library which had been prepared from human hepatoma cells (KYN-1). 9. Sequence analysis of the open reading frame revealed two possible nuclear localization sequences and several clusters of acidic amino acid residues, including a continuous run of 11 glutamic acid residues. 10. Northern blot analyses of human hepatoma RNA revealed hybridization to three transcripts which are about 4.1, 3.6, and 0.6 kb in size. 11. Dot blot analyses show that these transcripts are about 10-fold more abundant in KYN-1 hepatoma cells than in normal liver cells.

Amino Acid Sequence↗

Studies on host specificity in Paragonimus westermani: ultrastructural study of inflammatory reactions to the parasite in rat muscles.

Inflammatory reactions to the lung fluke, Paragonimus westermani, in an abnormal host, the rat, were studied by electron microscopy. Inflammatory cells accumulated around the worms in rat muscles, but the reaction varied significantly in intensity as well as distribution of inflammatory cells from worm to worm in the same and different hosts. In an accumulation of inflammatory infiltrates around the worm, eosinophils were more commonly seen, and neutrophils and macrophages were fewer in number. Mast cells appeared rarely. Where inflammatory cells touched to the worms, the tegument of the worms was covered with moderately electron-dense flocculent material which included dense granules. This material, which probably consisted of immune complexes of host antibody and antigen secreted from tegumental granules, seemed to block the inflammatory cells from adhering to the worm surfaces. Inflammatory cells made direct contact with worm surfaces where flocculent material was absent. Dense secretory material was discharged from some eosinophils as a result of degranulation.

Animals↗

Genetic transformation of industrial yeasts using an amino acid analog resistance gene as a directly selectable marker.

Prototrophic and often polyploid yeasts of industrial use require some dominant genes as directly selective markers for the transformation. We examined the applicability of a dominant gene, ARO4-OFP, which causes the resistance to PFP plus tyrosine, to direct selection of the transformants from 2 laboratory and 6 industrial strains, including bakers', distillers', winery, and saké yeasts. Although the transformation rates were low and seemed different among strains, the ARO4-OFP gene was applicable to all strains tested for direct selection of the transformants.

Biotechnology↗

Spontaneous globoid mineralization in the cerebellum of rats.

Cerebellar globoid mineralization in two rats was examined by light and electron microscopy, and by X-ray microanalysis. The mineralization was round to oval in shape; it varied in size and was positive for the periodic acid-Schiff and von Kossa reactions. Ultrastructurally, a concentric lamellar structure was prominent in moderately electron-dense depositions. Elemental analysis revealed the presence of large amounts of calcium and phosphorus, and small amounts of zinc, potassium and aluminum.

Animals↗

Cyclic stretch increases alkaline phosphatase activity of osteoblast-like cells: a role for prostaglandin E2.

We investigated the effects of applied cyclic stretch on osteoblast-like cells using a computerized, pressure-operated instrument that physically deforms the cells. Cyclic stretch increased DNA and collagenous protein synthesis and enhanced alkaline phosphatase activity in the cells. These effects were considered to be regulated through prostaglandin E2 production since this stretch reduced the levels of prostaglandin E2 in the medium and when prostaglandin E2 was added exogenously, there was a significant decrease in the alkaline phosphatase activity.

Alkaline Phosphatase↗