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Biomedical subjects

M Fukuda

Publications and source records attributed to M Fukuda.

At least 955 records · Page 53Linked to original sources
PubMed1989

Structure of human lysosomal membrane glycoprotein 1. Assignment of disulfide bonds and visualization of its domain arrangement.

The amino acid sequence of one of the major lysosomal membrane glycoproteins, lysosome-associated membrane protein 1 (lamp-1), was deduced from its cDNA sequence (Fukuda, M., Viitala, J., Matteson, J., and Carlsson, S. R. (1988) J. Biol. Chem. 263, 18920-18928). This amino acid sequence suggests that lamp-1 contains a hinge-like structure and could form disulfide bridges that are observed in the immunoglobulin superfamily. To test this possibility, we have determined the positions of the disulfide bridges by isolating and sequencing cystine-containing peptides which contain disulfide bridges. The results indicate that disulfide arrangement of lamp-1 is different from that of immunoglobulins. Each molecule contains, in total, four loops formed by disulfide bonds, and each loop contains 36-39 amino acid residues. However, none of the disulfide bonds connects two domains that are separated by a hinge-like structure. The results indicate that the hinge region has no ordered structure, and the relative positions of the two domains can be altered in space. Examination of the ultrastructure of lamp-1 by electron microscopy showed that the hinge-like structure actually functions as a hinge. These results indicate that the lamp-1 molecule represents a novel family of glycoproteins with unique structural properties.

Amino Acid Sequence↗
PubMed1989

Phosphorylation of the major leukocyte surface sialoglycoprotein, leukosialin, is increased by phorbol 12-myristate 13-acetate.

Leukosialin (CD43) is a heavily O-glycosylated membrane glycoprotein present on all leukocytes and on platelets. We found that leukosialin is phosphorylated in erythroid, myeloid, and T-lymphoid cell lines, as well as in platelets and peripheral blood lymphocytes. Leukosialin phosphorylation was increased 2.5-15-fold following phorbol ester treatment. The phosphorylation could be inhibited with the protein kinase C inhibitor staurosporine but not with HA 1004 that inhibits cAMP- or cGMP-dependent protein kinases. The phosphoamino acid analysis showed that serine residues were exclusively phosphorylated, either with or without phorbol ester treatment. Two-dimensional peptide maps of phosphorylated leukosialin from K562 and Jurkat cells gave almost identical patterns. The number of labeled peptides increased after treatment with phorbol ester, indicating that new sites were phosphorylated. The major phosphorylation site on leukosialin was identified as Ser-332 in a region of the cytoplasmic domain located 73 amino acids from the transmembrane portion.

Alkaloids↗
PubMed1989

Dose escalation study of recombinant human granulocyte-colony-stimulating factor (KRN8601) in patients with advanced malignancy.

To evaluate the toxicity and efficacy of recombinant human granulocyte-colony-stimulating factor (rh G-CSF) administered with intensive chemotherapy, 39 patients with advanced pulmonary cancers were enrolled in a dose escalation trial of rh G-CSF. Three days after initiation of chemotherapy rh G-CSF was administered i.v. for 14 consecutive days at five dose levels (50-800 micrograms/m2). Absolute neutrophil counts showed a dose-dependent increase with an increasing dose of rh G-CSF and the durations of neutropenia (less than 1000/mm3) shortened significantly at doses of 200, 400, and 800 micrograms/m2 compared to those at 50 micrograms/m2 (P less than 0.01). The duration of neutropenia was shortened significantly at all five dose levels following treatment with rh G-CSF compared to treatment without rh G-CSF (P less than 0.05). Adverse side effects associated with rh G-CSF administration were fever higher than 38 degrees C (21%), chest pain, and low back pain (13%). No intolerable side effects were experienced. It can be concluded that rh G-CSF is effective in shortening the duration of neutropenia following intensive chemotherapy at a dose level of 100 to 200 micrograms/m2 i.v. a 400-micrograms/m2 dose of rh G-CSF is recommended in patients with prior treatment because of the possibility of a lower bone marrow response.

Adult↗
PubMed1989

In vitro evaluation of the new anticancer agents KT6149, MX-2, SM5887, menogaril, and liblomycin using cisplatin- or adriamycin-resistant human cancer cell lines.

A new model to predict antitumor activity of new analogues was developed, and the cross-resistance against cisplatin (CDDP) and Adriamycin (ADM) was examined. A preclinical evaluation of various new analogues using this new model was performed. The antitumor activities of KT6149, MX-2 (KRN8602), SM5887, menogaril (TUT-7), and liblomycin (NK313) were evaluated against four non-small cell lung cancer cell lines, PC-7, -9, -13, and -14; two small cell lung cancer cell lines, H69 and N231; four CDDP-resistant cell lines, PC-7/1.0, PC-9/0.5, PC-14/1.5, and H69/0.4; a human myelogenous leukemia cell line, K562; and its ADM-resistant subline, K562/ADM by clonogenic assay. The relative antitumor activities of these new analogues were compared with those of parental agents, mitomycin C, ADM, bleomycin, and several anticancer drugs, CDDP, daunomycin, vindesine, and etoposide. KT6149 was more active than mitomycin C against all lung cancer cell lines and the human myelogenous leukemia cell line. Menogaril showed greater activity than ADM, and MX-2 showed activity similar to ADM. However, the antitumor activity of SM5887 was lower than that of ADM. SM5887 and menogaril showed cross-resistance to K562/ADM. Nevertheless, the antitumor activity against K562/ADM of MX-2 was similar to that of the parental cell lines. The activity of liblomycin was similar to that of bleomycin. Thus, KT6149 appears to be the best analogue for use in a clinical trial against lung cancer. MX-2 was active even against ADM-resistant cancer cells. The values of relative resistance to CDDP or ADM were 4.7, 8.1, 7.5, 20.0, and 13.6 for PC-7/1.0, PC-9/0.5, PC-14/1.5, H69/0.4, and K562/ADM, respectively. CDDP-resistant cell lines showed no cross-resistance with other drugs in this study. K562/ADM showed cross-resistance against daunomycin, etoposide, and vindesine. In contrast, mitomycin C and bleomycin had nearly equal activity against K562 and K562/ADM. However, K562/ADM was 2.4-fold more sensitive to CDDP than its parental cell line, K562 (P less than 0.001). These results suggested that the mechanism of CDDP resistance is different from that of multidrug resistance.

Anthracyclines↗
PubMed1989

Delay of astrocyte reaction in the injured cerebral cortex of hypothyroid mouse.

Reactive change in the number of astrocytes in the stabbed cerebral cortex (layers II-VI) of the hypothyroid mouse was studied quantitatively over a 4-day period after stabbing, by immunohistochemistry for glial fibrillary acidic protein (GFAP) and S-100 protein. The reactive increase in the number of GFAP-positive astrocytes was delayed in the hypothyroid mouse, compared to that in the euthyroid mouse. The number of S-100-positive astrocytes neither increased nor decreased significantly in the hypothyroid and the euthyroid mice. [3H]Thymidine autoradiography showed that the time course and intensity of the reactive proliferation of astrocytes were the same in the hypothyroid mouse as in the euthyroid mouse. These results indicate that hypothyroidism delays the reactive expression of GFAP-antigen and delays the transformation of GFAP-negative astrocytes into GFAP-positive reactive astrocytes.

Animals↗
PubMed1989

[On the assessment of the diagnostic accuracy of imaging diagnosis by ROC and BVC analyses--in reference to X-ray CT and ultrasound examination of liver disease].

To achieve an effective assessment of diagnostic accuracies of currently used imaging methods on liver diseases, X-ray CT (CT) and realtime ultrasound (US), ROC analysis and a new analysis method, "the bias to variance characteristics (BVC)" were applied in parallel. The survey has been carried out to assess an image interpretation accuracy on cases with established diagnosis collected on the multi-institutional basis. The images, CT and US of liver diseases including localized and diffuse lesions were selected for image reading sessions and the interpretative difficulties were geared to an appropriate grade so that it does fit to the basic requirement of ROC analysis. Consequently, 91 cases were selected from a total of 258 cases which were collected from 16 institutions. Two image reading sessions were scheduled and a total of 28 radiologists and sonologists undertook the first session. The final analysis covered 8 radiologists for CT and 9 sonologists who carried out both sessions. The image interpretation results were fed to the computer and analyses were made accordingly. Analysis of the first image reading session gave true positive ratios (TPR) of CT and US as 92.5% and 97.4%, and true negative ratios (TNR) of 50.5% and 46.8%, respectively. The second reading session, in which both CT and US images were interpreted simultaneously, gave the similar values of TPRs, 96-97% and TNRs, 44-47%. The ROC analysis of existence of liver mass and diagnosis of malignancy resulted in the higher values in US compared to CT in the first separate reading, however, the 2nd session gave almost identical values in each modality. The diagnostic accuracy for the benign tumors, mostly consisted of hemangioma, CT reading gave higher accuracy rates compared to the US. The entirely new interpretations scheme, arbitrarily named as BVC was carried ou on matrix data obtained in the same experiment. The scatterograms plotted according to the BV values, the mean and the standard deviation inherent to individual cases have demonstrated marked variations among individual cases most likely reflecting the interpretative difficulty of respective images, thus indicating the method to be well in adjunct to the ROC analysis.

Adult↗
PubMed1989

O-glycosylation of leukosialin in K562 cells. Evidence for initiation and elongation in early Golgi compartments.

The O-glycosylation of leukosialin, a major sialoglycoprotein found on leukocytes, has been studied in the human erythroleukemic cell line K562. The appearance of its O-linked chains has been followed in pulse-chase experiments with [35S]methionine by immunoprecipitation with an anti-peptide antiserum as well as with a lectin from Salvia sclarea seeds (SSA) specific for GalNAc-Ser/Thr and the peanut (Arachis hypogaea) agglutinin (PNA) which recognizes Gal beta 1----3GalNAc-Ser/Thr structures. An O-glycan-free precursor was converted into the fully O-glycosylated mature form within the 10-min labeling period and no intermediates carrying only GalNAc-Ser/Thr structures could be detected. The ionophore monensin was used in order to slow down intracellular traffic and thus O-glycan synthesis. The drug partly inhibited the transport from rough endoplasmic reticulum (RER) to the Golgi and also the cell-surface expression of leukosialin. It was found to have a marked effect on the synthesis of O-linked carbohydrate structures of leukosialin since the amount of O-glycans containing only GalNAc or NeuNAc alpha 2----6GalNAc was significantly increased after monensin treatment. Under these conditions the biosynthesis of the N-glycan on leukosialin was completely arrested in an endoglycosidase-H-sensitive step of processing, whereas the O-glycans already contained galactose and sialic acid although at a reduced level. On the other hand, the small amounts of leukosialin expressed on the cell surface of monensin-treated cells carried the same glycans as those remaining blocked inside the cell. In addition, immunocytochemical studies using SSA and PNA on untreated K562 cells suggested the absence of detectable amounts of GalNAc-Ser/Thr-bearing glycoproteins in the RER as well as in the Golgi. In contrast Gal beta 1----3GalNAc structures could be detected on intracellular membranes which were tentatively identified as the cis-Golgi. Together these results lead us to the following conclusions: N-glycan transfer occurs in the RER before the initiation of O-glycans which takes place at the entrance of the protein into the Golgi; further elongation of O-glycans with galactose and sialic acid follows very rapidly, probably before the final processing of N-glycans to complex-type structures.

Antigens, CD↗
PubMed1989

Effects of very-low-calorie diet weight reduction on glucose tolerance, insulin secretion, and insulin resistance in obese non-insulin-dependent diabetics.

We put 12 obese subjects on a very-low-calorie diet (VLCD) and observed how their weight loss affected their glucose tolerance. Seven had non-insulin-dependent diabetes and five did not. They consumed 1000 kcal/day for at least 1 week, then 420 kcal/day for 4 weeks, and 1000 kcal/day thereafter. VLCD improved glucose tolerance and insulin response to a glucose load in the diabetics and did not affect these parameters in the non-diabetics. It did not change insulin responsiveness to intravenous glucagon in either group. Both groups showed improved insulin resistance, as measured by an insulin suppression test. Regression analysis showed that insulin resistance correlates well with obesity and glycemic control. Weight reduction did not change hepatic insulin extraction. Thus, the improvement in glucose tolerance by some of the diabetics seems to have arisen from improvements in their insulin resistance and insulin response to a glucose load. Insulin resistance improved because of weight reduction and subsequent improvements in glycemic control.

Adult↗
PubMed1989

Reactions of S-100-positive glia after injury of mouse cerebral cortex.

Reactions of glial cells after stab wounding of mouse cerebral cortex were studied by [3H]thymidine autoradiography combined with immunohistochemistry for S-100 protein. S-100-positive cells in the stabbed cortex had the light and electron microscopic characteristics of astrocytes, and they showed remarkable hypertrophic changes 4 to 5 days after stabbing. There were many cells labeled with [3H]thymidine in the stabbed cortex from 24 h to 8 days after stabbing, and the number of labeled cells was maximum at 48 h. A few of the labeled cells were S-100-positive, and the labeled S-100-positive cells were seen 24 h to 6 days after stabbing, mostly after 72-96 h. By successive injections of [3H]thymidine for 6 days after stabbing, about 90% of labeled cells were S-100-negative, and about 90% of S-100-positive cells were unlabeled with [3H]thymidine. The increase in number of S-100-positive cells by day 6 after stabbing was not statistically significant (P greater than 0.05). These results suggest that reactive proliferation of astrocytes is a minor phenomenon in gliosis of injured cerebral cortex, in contrast with their remarkable reactive hypertrophy.

Animals↗
PubMed1989

Distribution of fibronectin and laminin in early and advanced signet-ring-cell carcinomas of the stomach.

An immunoperoxidase method was used to compare the distribution of fibronectin and laminin between superficially spreading and deeply infiltrating parts of signet-ring-cell carcinoma of the stomach. In both parts, laminin-containing basement membranes were generally scarce, but they were observed on some of the cancer cells which had differentiated to glandular cells. Intramucosal invasion fronts of superficially spreading cancers often showed a layered structure, consisting of a middle zone of small cancer cells together with a superficial and a deep zone of signet-ring cells. In this structure, linear fibronectin and laminin deposits were common on the cancer cells in the deep zone, but rare in the superficial zone. However, fibrillar fibronectin deposits in the stroma were not considerably larger in either zone. At extramucosal invasion fronts of deeply infiltrating (advanced) cancers, a stromal remodelling with an increased amount of fibrillar fibronectin deposits was often observed around the cancer cells, whose cell surface fibronectin was largely lost even from some basement membranes. These findings suggest that invasive activity of signet-ring-cell carcinoma may not be related to the mere presence or absence of cell-surface fibronectin and laminin but to the amount of stromal fibronectin, which could reflect a cell-stroma interaction. Signet-ring-cell carcinomas have a stage of intramucosal growth in which cancer cells may live in dependence upon the pre-existing stroma and form the layered structure, while in advanced stages cancer cells seemed to have acquired an ability to elicit their own "tumor stroma".

Adenocarcinoma, Mucinous↗
PubMed1989

Production of monoclonal antibody to human IgG allotype G3M T.

An efficient method for the production of monoclonal anti-G3M T antibody is described. IgG3 protein of GM B3ST phenotype was isolated by affinity chromatography on Ricinus communis lectin I-agarose and used for immunization. A mouse hybridoma clone was obtained by fusion of popliteal lymph node cells and P3U1 myeloma cells. The antibody produced was tested for allotype specificity by hemagglutination inhibition and ELISA methods using 101 IgG-allotyping control sera. The antibody was neutralizable by all G3M T-positive sera and entirely nonneutralizable by G3M T-negative sera in the inhibition test, and reacted only with G3M T-positive IgG coats in the ELISA test. The results prove the antibody to be allotype-specific, and therefore practically establishes its monoclonality.

Antibodies, Monoclonal↗
PubMed1989

Barbiturates protect retinal cells from hypoxia in cell culture.

A culture system was used to screen for drugs that can protect mammalian retinal cells from damage induced by hypoxia. Using a special incubator, cultures could be made hypoxic for defined periods. Phase contrast photomicroscopy facilitated comparison of retinal cells before hypoxia and 1 to 2 days after hypoxia. Using 2- to 3-week-old cultures, certain glutamate antagonists, anesthetics, calcium blockers, and thiopental sodium were screened for their effect in protecting cells from hypoxia. The most remarkable effect was noted with thiopental. Quantitative measurements showed a significant increase in the percent of cells surviving after exposure to hypoxia in the presence of 100 mumol/L of thiopental sodium compared with control hypoxic cultures--82% vs 59% at 48 hours. A dose-response curve demonstrated maximal effect at 50 mumol/L of thiopental sodium, with toxic effects noted at 200 mumol/L of thiopental sodium. Our results show that thiopental reduces hypoxia-induced damage to retinal cells in culture.

Animals↗
PubMed1989

Acrosomal function of human spermatozoa with normal and abnormal head morphology.

In previous studies we have shown differences in the function of morphologically normal and abnormal sperm by evaluating their flagellar movements and swimming trajectories. In this study we have compared the capability of morphologically normal and abnormal human sperm to undergo an acrosome reaction after incubation with human follicular fluid. Semen samples were studied from 6 research donors and 21 semen evaluation patients. All men had normal semen by clinical criteria. Semen was prepared either by a two-step Percoll gradient centrifugation or the sperm were diluted, washed, and centrifuged three times. Sperm suspensions were incubated for 24 hours in a modified Tyrode's medium, containing 2.6% bovine serum albumin, prior to dilution with human follicular fluid. The percentage of acrosome reactions among viable sperm was assessed after 15 minutes using the supravital Hoescht stain and fluoresceinated pea lectin. Sperm head size was measured with an ocular micrometer and normal values were defined as length 3-5 microns and width 2-3 microns. At least 25 viable normal sperm, and 25 viable abnormal sperm were analyzed for acrosome reactions on each slide. With Percoll separation the percentage of acrosome reactions (mean +/- sem) for normal sperm was 38 +/- 3% vs. 22 +/- 2% for abnormal sperm (P less than 0.005). After washing, the comparable values were 12 +/- 1% vs. 5 +/- 1% (P less than 0.005). The incidence of spontaneous acrosome reactions (24 hours of incubation, no follicular fluid) was also higher for normal sperm than abnormal sperm (9 +/- 1% vs. 4 +/- 1%, P less than 0.01). These data demonstrate an association between normal sperm morphology and acrosomal function.

Acrosome↗
PubMed1989

Pharmacokinetics of (glycolate-0,0')-diammine platinum (II), a new platinum derivative, in comparison with cisplatin and carboplatin.

The pharmacokinetics of (glycolato-0,0')-diammine platinum (II) (254-S; NSC 375101D), one of the new platinum analogues, was examined in a phase I study of this drug and compared with that of cisplatin and carboplatin. All drugs were given in short-term (30-min) i.v. drip infusions; the doses of 254-S, cisplatin, and carboplatin were 100, 80, and 450 mg/m2, respectively. Platinum concentrations in whole plasma, plasma ultrafiltrate, and urine were determined by atomic absorption spectrometry. After the infusion, the plasma concentration of total platinum for the three agents decayed biphasically. Ultrafilterable platinum in plasma decreased in a biexponential mode after infusions of 254-S and carboplatin, whereas the free platinum of cisplatin showed a monoexponential disappearance. The peak plasma concentrations and AUC for free platinum were 5.31 micrograms/ml and 959 micrograms/min per ml for 254-S, 3.09 micrograms/ml and 208 micrograms/min per ml for cisplatin, and 19.90 micrograms/ml and 3446 micrograms/min per ml for carboplatin, respectively. The mean ratio of plasma ultrafilterable platinum to total platinum were calculated, and the results showed that the protein-binding abilities of 254-S and carboplatin were almost identical. More than 50% of the 254-S was excreted in the urine within the first 480 min after its administration. Thrombocytopenia was reported as a dose-limiting toxicity for both 254-S and carboplatin. This similarity in side effects may mainly be due to the comparable pharmacokinetic behavior of these two platinum compounds.

Antineoplastic Agents↗
PubMed1989

The effect of long-term topical administration of commercial beta-blockers on the rat corneal endothelium.

To determine the effect of long-term topical application of commercial beta-blockers on the corneal endothelium, normal rats were randomly assigned to receive a drop of 0.5% timolol, 1% befunolol, or 2% carteolol four times daily for 8 months. Specular microscopy showed marked pleomorphism in the endothelium after three months of treatment with 1% befunolol. In contrast, the eyes treated with either 0.5% timolol or 2% carteolol demonstrated no significant change in endothelial morphology. Scanning and transmission electron microscopy at eight months after treatment revealed marked degeneration of the endothelium of the eyes treated with 1% befunolol. Similar endothelial changes were also noted in the 0.5% timolol-treated group, but to a significantly lesser extent. The eyes treated with 2% carteolol, however, showed only mild alteration of the endothelial ultrastructure. These results indicate that the corneal endothelium can be affected by long-term topical administration of commercial beta-blockers.

Administration, Topical↗
PubMed1989

Carcinoma arising in fibroadenoma of the breast--a case report and review of the literature.

A 47 year old woman with two isolated lumps in her right breast underwent an excisional biopsy and the histological findings of both lesions revealed fibroadenoma with an in situ lobular carcinoma. Patey's modified radical mastectomy was performed after which careful follow-up was continued. To date, a total 161 cases of carcinoma arising in a fibroadenoma have been reported in the world literature and a review of these literature is given following the case report.

Adenofibroma↗