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Biomedical subjects

K Fujiwara

Publications and source records attributed to K Fujiwara.

At least 469 records · Page 26Linked to original sources

Enzyme-linked immunosorbent assay (ELISA) for luteinizing hormone releasing hormone (LH-RH) using a heterobifunctional cross-linking agent, N-[beta-(4-diazophenyl)ethyl]maleimide.

Luteinizing hormone-releasing hormone (LH-RH) was first labeled with an enzyme, beta-D-galactosidase (beta-Gal; EC 3.2.1.23), using N-[beta-(4-diazophenyl)ethyl]maleimide (DPEM) as a heterobifunctional cross-linking agent. An antigen was similarly prepared by coupling LH-RH to mercaptosuccinylated bovine serum albumin with DPEM and was used for the immunization of rabbits for antibodies against LH-RH. A new, simple enzyme-linked immunosorbent assay (ELISA) for LH-RH was developed by using the principle of direct competition between LH-RH and beta-Gal-labeled LH-RH for anti-LH-RH IgG which had been adsorbed to the plastic surface of microtiter plates. LH-RH concentrations lower than 50 pg/assay well were measurable reproducibly by the ELISA, the sensitivity of which was found to be about 6250 times greater than the corresponding high performance liquid chromatography (HPLC) procedure. The specificity of this ELISA seems to be primarily toward the C-terminal region of LH-RH, showing a cross-reaction with the LH-RH6-10 fragment to the same extent as with LH-RH, but no cross-reaction with the LH-RH1-3 and LH-RH4-6 fragments. Using this assay, LH-RH levels were easily measured in the blood and urine of rats following the administration of LH-RH in a single dose of 0.5 mg/kg i.v. The present, newly developed ELISA is a nonradioactive, inexpensive and rapid method, and might be useful for elucidating experimental hypothalamic-pituitary-gonad interactions.

Amino Acid Sequence↗

Effects of hepatic enzyme inducers and mitogens on experimental Tyzzer's disease in rats.

We studied the effects of chemicals which induce liver enlargement and can induce hepatic protein synthesis on experimental Tyzzer's disease in rats. Plasma transaminase values were evaluated as an indicator of the severity of the disease. Chemicals used were phenobarbital sodium and 3-methylcholanthrene as hepatic enzyme inducers, and lead nitrate and ethylene dibromide as mitogens of hepatocytes. In rats non infected with Tyzzer's organism, liver weight in those treated with these chemicals was higher than that in rats without chemical treatment. Tyzzer's disease-infected rats treated with these chemicals showed higher plasma transaminase values and more severe histopathologic liver lesions than infected rats without chemical treatment. The results indicated that the growth of Tyzzer's organisms in hepatocytes was accelerated in the course of hepatocytic metabolic changes during liver enlargement, and that protein synthesized in the hepatocyte may play an important role in the nutritive requirements of the organism.

Alanine Transaminase↗

Expression of a lymphocyte adhesion molecule (CD44) in malignant lymphomas: relevance to primary site, histological subtype and clinical stage.

Lymphocyte adhesion molecules defined by anti-CD44 antibody (Hermes-3) may be involved in lymphocyte binding to high endothelial venules at sites where lymphocytes exist the blood. CD44 expression was immunohistochemically examined in 167 well characterized cases of malignant lymphomas (MLs). None of 12 nodal follicular lymphomas (FLs) were CD44+, whereas 3 of 4 extranodal ones showed distinct CD44 expression. In contrast to nodal FLs, 28 of the 38 (74%) nodal diffuse B-cell lymphomas were CD44+ (p < 0.0001). T-cell lymphomas showed a significantly higher expression of CD44 antigen than diffuse B-cell lymphomas in the nodal cases (p < 0.04), but not in the extranodal ones. In nodal diffuse lymphomas, 3 of 5 stage I lymphomas (60%) were CD44+ in contrast to 53 of 63 stage II-IV lymphomas (84%), but the difference was not statistically significant. Of 14 Hodgkin's diseases, 9 cases were CD44+ with no significant correlation with clinical stage. The data of flow cytometric analysis confirmed the results of immunohistochemical analysis. In conclusion, CD44 expression is relevant to primary sites of distinctive MLs originating in the mucosal regions (MALToma) and some histological subtypes, but the relation with clinical stage was not defined. Some other adhesion molecules or different mechanisms must also be taken into account concerning the genesis and the expansion of MLs.

Humans↗

Distribution of lectin receptors in the human hyperplastic tonsil: histochemical and flow cytometric analyses.

The distribution of lectin receptors in the human tonsil was studied using 16 biotinylated lectins. The avidin-biotin-peroxidase complex (ABC) method was used on frozen and paraffin-embedded tissue sections. Cell suspensions were also analysed by dual flow cytometry using respective fluorescein isothiocyanate-conjugated lectins and phycoerythrin-labeled anti-CD3 and anti-human immunoglobulin. Frozen sections fixed with acetone and paraffin-embedded materials fixed in three solutions were compared for lectin affinity; ethanol-fixed sections gave best results followed by frozen and buffered formalin-fixed ones, then nonbuffered formalin. Con-A, RCA-1, LcH, WGA, MPA, PHA, PSA, PNA, SJA and GSA-1 reacted with all tissue components of the tonsil in immunohistochemical studies, but binding intensity was fixative dependent. Binding of Lotus and BPA to lymphocytes was limited to germinal center lymphocytes. Other tissue components were also reactive but staining intensity was weaker in Lotus compared with BPA. SBA and DBA did not react with lymphocytes, but reacted with macrophages/histiocytes, vascular endothelia, and epithelial cells. LBA and LPA were constantly negative with all tissue components irrespective of fixatives. Flow cytometric analyses showed that all but three (DBA, LBA and LPA) partially or totally stained lymphocyte surfaces. Lotus receptors were expressed exclusively on B-lymphocytes.

Acetone↗

Successful treatment of hypothyroid Graves' disease with a combination of levothyroxine replacement, intravenous high-dose steroid and irradiation to the orbit.

A 46-year-old woman with hypothyroid Graves' disease (EMO syndrome) is reported. The patient had bilateral exophthalmos, conjunctival chemosis, periorbital edema and limitation of lateral gaze. Laboratory examination revealed the presence of primary hypothyroidism with positive thyroid-stimulating hormone (TSH) binding inhibitory immunoglobulin and thyroid stimulation antibody. These findings indicated a diagnosis of hypothyroid Graves' disease or EMO syndrome. She received levothyroxine replacement and steroid pulse therapy followed by radiotherapy. Her visual symptoms showed marked improvement and pretibial myxedema disappeared. Although several studies indicate that hypothyroid Graves' disease is a different entity from hyperthyroid Graves' disease, this report suggests that steroid pulse therapy combined with radiotherapy may be effective to treat ophthalmopathy in both diseases.

Combined Modality Therapy↗

Analysis of viral infection in patients with IgA nephropathy.

We investigated viral infections in the tonsils, pharynx and renal tissues of patients with IgA nephropathy using cell culture, polymerase chain reaction (PCR) and immuno-fluorescent techniques, and measured antibody titers against numerous types of viruses. Neutralization tests found no significant inhibition of growth of adenovirus-1, 2, 3, 4, 5, 6, 7, 11 or 19, Coxsackie virus-A7, A9, A16, B1, B2, B3, B4, B5 or B6, or RS virus. Swabs of the oral cavity of patients with IgA nephropathy were cultured with Hel cells, MDCK cells, FL cells, BHK-21 cells and RD-18S cells. No cytopathic effect was detected in any of these cell cultures. We failed to detect the presence of herpes simplex virus-1 and -2, varicella-zoster virus, cytomegalovirus and Epstein-Barr virus (EBV)-1 and -2 in tonsils, renal tissues and mouthwashings from patients with IgA nephropathy. On the other hand, EBV alone was detected with the PCR technique, in mouthwashings from 6 out of 14 patients with IgA nephropathy (42%). Immunohistological and serological analyses were done to examine the relationship between EBV and IgA nephropathy. No evidence was obtained that EBV-infected B lymphocytes were producing IgA. It seems unlikely that the viral infections examined in this study play a significant role in the pathogenesis of IgA nephropathy.

Adult↗

Morphological responses of single endothelial cells exposed to physiological levels of fluid shear stress.

To investigate the basic processes underlying flow induced morphological changes of vascular endothelial cells (ECs), we have examined the responses of single ECs to fluid mechanical forces under controlled flow conditions in vitro. We made a parallel plate culture flow chamber which could be mounted on an inverted microscope equipped with various optical systems. Video-enhanced microscopic images were recorded with a time-lapse, laser video-disk recorder and then analyzed frame by frame. In contrast to ECs in a confluent monolayer, ECs in sparse culture did not show a parallel alignment to the flow direction even after a 100 h exposure to flow at a wall shear stress level of 10 dyne/cm2. However, rapidly after changing from a weak shear stress (1 dyne/cm2 or less) to a high shear stress (6 dyne/cm2 or more), sparsely cultured ECs extended lamellipodia predominantly on the downstream side and began to migrate preferentially downstream. If the viscosity of the circulating medium was raised by adding a small amount of methyl cellulose or polyvinylpyrrolidone, ECs exhibited these characteristic morphological changes under low wall shear rates (100 s-1 or less). We also found that these changes required Ca2+ in the circulating medium. These results indicate that single ECs can respond to flow in a rapid, shear stress and Ca2+ dependent manner.

Animals↗

Stimulation of liver growth by exogenous human hepatocyte growth factor in normal and partially hepatectomized rats.

Human hepatocyte growth factor stimulates DNA synthesis by cultured rat hepatocytes. When human hepatocyte growth factor prepared from the culture medium of human embryonic lung fibroblasts was intravenously injected into normal rats and rats after 70% hepatectomy, it was detected in hepatocytes but not in nonparenchymal cells isolated 30 min after injection. Similar injections of human hepatocyte growth factor at 2-hr intervals for 10 hr significantly increased hepatic DNA content in normal rats at 48 hr, with increased hepatic content of putrescine, the essential polyamine for hepatic DNA synthesis after 70% hepatectomy, and activities of catalytic enzymes of putrescine synthesis at 6 hr almost to the levels in rats after 70% hepatectomy. Those levels in rats after 70% hepatectomy were further enhanced by similar injections of human hepatocyte growth factor starting immediately after surgery. Increased hepatic DNA content in normal rats and rats after 70% hepatectomy was also seen with recombinant human hepatocyte growth factor to a greater extent compared with that seen with human hepatocyte growth factor. In normal rats given recombinant human hepatocyte growth factor, 5-bromo-2'-deoxyuridine-labeled and mitotic hepatocytes were significantly increased in number at 26 hr but not at 48 hr. We conclude that exogenous human hepatocyte growth factor acts as a trigger and a promoter of liver growth to increase hepatic putrescine production in rats. Recombinant human hepatocyte growth factor is more potent than human hepatocyte growth factor in this action.

Animals↗

Effect of recombinant human erythropoietin administration on immunological indices in patients undergoing chronic hemodialysis.

In patients undergoing chronic hemodialysis, marked anemia may cause decreased immunological function. To improve this anemia, we investigated the effect on immunological indices of recombinant human erythropoietin (rHuEPO) administration in 24 hemodialysis patients (13 males and 11 females) with renal anemia complications. Their mean age was 54.9 +/- 14.8 years and the mean duration of dialysis was 100.5 +/- 54.9 months. The subjects were treated with rHuEPO for 12 months, which helped to maintain a hematocrit value elevated by 5% from the baseline. Cell-mediated immunity and humoral immunity were assessed prior to as well as throughout the treatment period. Of the total number of patients studied, the anemia of 16 improved while 8 did not show signs of sufficient improvement. The improved group showed an increase in in vitro lymphocytic response to phytohemagglutinin (PHA), CD4/CD8, CD16 and serum IgM levels, while the CD8 level decreased significantly. Improvement in the general physical condition with rHuEPO treatment appeared to be associated with the changes in immunological indices, but the precise mechanism remains obscure.

Adult↗

Serum levels of transforming growth factor-alpha in patients after partial hepatectomy as determined with an enzyme-linked immunosorbent assay.

A sandwich enzyme-linked immunosorbent assay for measuring serum transforming growth factor-alpha levels was developed with monoclonal IgM and polyclonal IgG antihuman transforming growth factor-alpha antibodies and a system to amplify the activity of the conjugated enzyme. The assay detected serum transforming growth factor-alpha levels as low as 5 pg/ml. Serum transforming growth factor-alpha levels were below the detection limit of the assay in 19% of healthy adults, with a mean (+/- S.D.) detectable level of 22.0 +/- 16.7 pg/ml. In 13 patients who underwent partial hepatectomy, serum transforming growth factor-alpha levels were determined serially after surgery. The levels were increased within 28 days of surgery in all the patients, with a mean maximal level of 118.2 +/- 90.8 pg/ml. The maximal level achieved in each case correlated significantly with the resected volume of the liver and the increased volume of the remaining liver 28 days after hepatectomy (r = 0.59, p < 0.05, and r = 0.71, p < 0.005, respectively). In contrast, serum transforming growth factor-alpha levels showed no increase after laparotomy for nonhepatic surgery. Serum transforming growth factor-alpha levels may vary depending on the regenerative stimulus and reflect the degree to which liver regeneration will occur in patients after partial hepatectomy.

Enzyme-Linked Immunosorbent Assay↗

[The sprotte needle decreases the incidence of postspinal headache].

Postspinal headache (PSH) is the most frequent complication of spinal anesthesia. The factors responsible for the development of PSH include needle size, shape of the needle tip, patient's age, sex, infusion volume and period of resting. The purpose of this study is to compare the incidence of PSH between two different types of needle, Sprotte needle and Quincke needle. The Sprotte needle is characterized by a round profiled tip equipped with a lateral orifice. Our investigation by questionnaires revealed that the incidences of PSH after using either 22G Sprotte needle or 21-25G Quincke needle were 0% and 38.8%, respectively. We conclude that the Sprotte needle decrease the incidence of PSH.

Adult↗

Inhibitory effects of indomethacin on growth and proliferation of gastric carcinoma cells KATO III.

The effects of indomethacin on growth and proliferation of gastric carcinoma cells KATO III were examined. Indomethacin (10(-4) and 10(-3) M) significantly inhibited cell growth and these effects were not affected by treatment with 16,16-dimethyl prostaglandin E2 (3 x 10(-7) M and 3 x 10(-6) M). Indomethacin 10(-3) M significantly reduced cell viability and completely inhibited cell growth. Indomethacin 10(-4) M did not affect cell viability and its inhibitory effect of cell growth became apparent on the fifth day of culture. Indomethacin 10(-4) M reduced BrdU labeling index within 2 hours. These results suggest that indomethacin inhibited growth and proliferation of gastric carcinoma cells KATO III. This effect is not mediated by prostaglandins.

Antineoplastic Agents↗

[Squamous papillomatosis of the left main bronchus and trachea: a case report].

A 49-year-old female complaining of dyspnea at exercise was admitted. Bronchoscopic examination revealed that the left main bronchus was almost obstructed by a tumor. A sleeve resection of the left main bronchus was performed. Histological examination confirmed that the tumor was squamous papilloma. After one year and eight months, bronchofiber examination disclosed papilloma in the trachea. Therefore, papilloma was treated with endoscopic methods, including Nd-YAG laser. The patient has survived for 11 years since first treatment.

Bronchial Neoplasms↗

[Brain protection on the aortic arch replacement--with deep hypothermic selective cerebral perfusion via right axillary artery].

Graft replacement was performed in the treatment of 31 patients with aneurysm involving the aortic arch from May, 1986 to December, 1992. Of the 31 patients, 16 had true aneurysm, 13 had aortic dissection and 2 had Annuloaortic ectasia. From May 1986 to May 1989, we did not have the policy about brain protection. Since June 1989, we performed the aortic arch surgery with deep hypothermic selective cerebral perfusion via right axillary artery and used open distal anastomosis technique. Besides, we exchanged the perfusion site to the ascending aorta when we finished the selective cerebral perfusion. In that way, brain complication rate was decreased from 57.1% to 11.7% and operative mortality was decreased from 85.7% to 29.1%.

Aged↗

Preservation of differentiated phenotypes in cultured aortic endothelial cells by malotilate and phosphoascorbic acid.

Confluent bovine aortic endothelial cells (BAECs) formed a cobblestone-shaped cell monolayer when cultured on a collagen gel in a 1:1 mixture of Dulbecco's modified Eagle's medium and Ham's-F12 supplemented with 5% newborn calf serum. Within a few days, however, they lost cell-cell attachment and became fibroblastic. When BAECs were cultured in the same culture medium but further supplemented with either 10 micrograms/ml malotilate or 1 mM phosphoascorbic acid, the monolayer organization and the cobblestone-like cell morphology were maintained for more than 2 weeks although many sprout cells were observed underneath the monolayer. In contrast, if both malotilate and phosphoascorbic acid were present in the culture medium, a tight monolayer without underlying sprout cells was maintained for at least 4 months and the cells expressed factor VIII-related antigens and massively internalized acetylated low density lipoprotein. By electron microscopy, we observed well-developed gap and adherence junctions, Golgi apparatuses and vesicles many of which were open to the outside by fusing with either the apical or the basal surface, indicating high metabolic activity of the cells cultured for weeks in the same dish. Although malotilate-treated BAEC monolayers secreted increased levels of prostacyclin (PGI2), the drug did not appear to directly affect the PGI2 production pathway since the similarly increased PGI2 production was noted in tight monolayers formed without the use of malotilate. Our results indicate that malotilate and phosphoascorbic acid together preserve differentiated phenotypes in cultured endothelial cells.

Animals↗

Expression of mature bovine H-protein of the glycine cleavage system in Escherichia coli and in vitro lipoylation of the apoform.

H-protein, a component of the glycine cleavage system with lipoic acid as a prosthetic group, was expressed in Escherichia coli using a T7 RNA polymerase plasmid expression system. After induction with 25 microM isopropyl-beta-D-thiogalactopyranoside, bacteria harboring the recombinant plasmid expressed mature bovine H-protein as a soluble form at a level of about 10% of the total bacterial protein. Little of the H-protein was lipoylated in E. coli cultured without added lipoate, but when the cells were cultured in medium supplemented with 30 microM lipoate, about 10% of the recombinant protein expressed was the correctly lipoylated active form, 10% was an inactive aberrantly modified form, presumably with an octanoyl group, and the remaining 80% was the unlipoylated apoform. Each of the three forms was purified to homogeneity and shown to have the same NH2-terminal amino acid sequence as that of native bovine H-protein. The specific activity of the lipoylated form of H-protein expressed was consistent with that of H-protein purified from bovine liver. The purified recombinant apo-H-protein was lipoylated and consequently activated in vitro with lipoyl-AMP as a lipoyl donor by lipoyltransferase purified 150-fold from bovine liver mitochondria. The lipoylation was dependent on lipoyl-AMP, apo-H-protein, and lipoyltransferase. The partially purified lipoyltransferase had no lipoate-activating activity. These results provide the first evidence that in mammals two consecutive reactions are required for the attachment of lipoic acid to the acceptor protein: the activation of lipoic acid to lipoyl-AMP catalyzed by lipoate-activating enzyme and the transfer of the lipoyl group to an N epsilon-amino group of a lysine residue to apoprotein by lipoyl-AMP:N epsilon-lysine lipoyltransferase.

Acyltransferases↗