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Biomedical subjects

H Itoh

Publications and source records attributed to H Itoh.

At least 19 recordsLinked to original sources

Specific blockade of basic fibroblast growth factor gene expression in endothelial cells by antisense oligonucleotide.

The migration and proliferation of endothelial cells play a pivotal role in various vascular diseases. To elucidate the role of endogenous basic fibroblast growth factor (bFGF) produced within endothelial cells on cell growth, we introduced the antisense oligonucleotide complementary to bFGF mRNA into cultured bovine aortic endothelial cells by cationic liposome to block the production of autocrine bFGF. The treatment of the endothelial cells with the specific antisense oligomer efficiently inhibited the synthesis of bFGF with the concomitant suppression of endothelial proliferation, indicating the significant role of bFGF as an endothelial growth promotor. The neutralizing antibody against bFGF had no inhibition on basal DNA synthesis of the endothelial cells, in contrast to marked suppressive action of bFGF antisense oligomer. The results provide the new analytic and therapeutic implications in the use of the antisense methodology for the study of vascular biology.

3T3 Cells

Secretion of cell-adhesion-promoting factors, fibronectin, fibronectin fragments and a 53-kDa protein, by human rectal adenocarcinoma cells.

Production of cell-adhesion proteins was examined in 10 cell lines and 5 cultured human cancer cells at an early passage. Two-thirds of the tested cells produced and secreted into their culture medium variable amounts of material active in promoting cell attachment. One of the rectal carcinoma cell lines, CaR-I, grew well in serum-free medium and secreted a large amount of the active principle. The active principles produced by CaR-I cells were characterized after partial purification, and were found to be fibronectin and its fragments. The presence of fibronectin and its fragments was proved by the following facts: (1) reactivity to the monoclonal antibodies which recognize different epitopes of fibronectin, and (2) reactivity to RGD peptide which is the attachment sequence of fibronectin. In addition to fibronectin and its fragments, CaR-I cells were also shown to produce a 53-kDa attachment factor. Unexpectedly, the protein was proved to be most probably the p53 suppressor gene product.

Adenocarcinoma

Lectin-like activity of Lactobacillus acidophilus strain JCM 1026.

The lectin-like activity of the Lactobacillus acidophilus strain JCM 1026 was studied by hemagglutination and hemagglutination-inhibition assays. L. acidophilus strain JCM 1026 was found to hemagglutinate human and animal erythrocytes. Neuraminidase-treatment of human-type O erythrocytes enhanced the activity. Treatment of the bacterial cells with proteinase K reduced hemagglutinating activity significantly. Although several mono- and disaccharides did not inhibit hemagglutination, several different glycoproteins did. These data indicate that a proteinaceous lectin-like component(s) recognizing carbohydrate-containing molecules is located on the cell surface of L. acidophilus.

Animals

[Hyperresponsiveness of TSH and prolactin and impaired responsiveness of GH in Japanese patients with isolated ACTH deficiency].

Two hundred and forty-one cases of isolated ACTH deficiency have been reported in Japan since 1969. Pituitary hormone responsiveness to stimulation tests before and after hydrocortisone supplementation was investigated in these cases. Plasma ACTH level showed no or little change in response to lysine vasopressin, metyrapone, CRF or insulin-induced hypoglycemia in 97.3-100% of the cases. Serum GH level changed little or not at all in response to GRF, insulin-induced hypoglycemia, glucagon, 1-dopa and arginine in 26.9, 29.3, 40.0, 50.0 and 56.1%, respectively. Serum TSH and prolactin (PRL) levels showed hyperresponse to TRH in 34.7 and 35.6%, respectively. After hydrocortisone therapy, GH secretion was more responsive than before therapy in 78.9% of the cases. After supplementation, TSH level was less responsive to TRH stimulation than before therapy in 59.3% of the cases. After hydrocortisone supplementation, TSH response to TRH decreased in 75% of ACTH-deficient patients without primary hypothyroidism but did not decrease in more than half of those with primary hypothyroidism. TSH response to TRH decreased after supplementation in 76.5% of the patients with TSH hyperresponsiveness before therapy, and increased after therapy in 66.7% of those with normal TSH responses before therapy. After supplementation, PRL response to TRH was less than that before therapy in 43.5% of ACTH--deficient patients, and greater than that before therapy in 30.4%. PRL response to TRH decreased after therapy in 66.7% of the patients with PRL hyperresponsiveness before therapy, and increased in 63.6% of those with normal PRL response before therapy. Primary hypothyroidism and Hashimoto's thyroiditis were complicated in 21.6 and 11.6%, respectively, of the 241 patients with isolated ACTH deficiency. In patients who had TSH hyperresponsiveness and/or high basal TSH levels and PRL hyperresponsiveness and/or high basal PRL levels, primary hypothyroidism was complicated in 58.4 and 42.3%, respectively. Hashimoto's thyroiditis was complicated in 29.8 and 20.5%, respectively, of these patients. Pituitary cell antibody (PCA) was detected in 36.6% of ACTH-deficient patients who were examined. Pituitary cell surface antibody (PCSA) to AtT-20 cells and GH3 cells was detected in 50.0 and 28.0% of the examined cases, respectively. The prevalence of PCA and PCSA did not differ between TSH-hyperresponsive patients and those with normal TSH basal levels and response, whereas PCA and PCSA were significantly more prevalent in PRL-hyperresponsive patients than in those with normal PRL levels and response. An empty sella was found in 30.2% of the examined case.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenocorticotropic Hormone

Concentration of serum laminin and type IV collagen in liver diseases assayed by a sandwich enzyme-immunoassay using monoclonal antibodies.

Serum laminin (P1 fragment) and type IV collagen levels were determined in patients with hepatic disorders. The method was based on a sandwich enzyme-immunoassay using two monoclonal antibodies that recognize different epitopes of either laminin or type IV collagen molecule. Laminin and type IV collagen levels in the serum of patients with chronic hepatic disorders were higher as compared with those in healthy control subjects, with the increment of serum type IV collagen being far greater than that of laminin. Since type IV collagen and laminin are major basement membrane components, it is suggested that the higher levels of these peptides may reflect a so-called capillarization of the perisinusoidal wall encountered in hepatic fibrogenesis. The assay system used in this experiment is simple and sensitive and can be applied to clinical evaluation of hepatic fibrosis.

Adolescent

Differences between vasorelaxant responses of the canine and human mesenteric arteries and veins to amrinone.

Amrinone induced similar degrees of relaxation in human mesenteric arteries and veins contracted with KCl, but exerted a more potent vasodilator effect in canine mesenteric veins than in arteries. Dibutyryl cAMP had a stronger effect on KCl-induced contraction in canine mesenteric veins than in arteries. These results suggest that amrinone promotes a different vasodilating action in human and canine mesenteric vessels, possibly via different sensitivity to cAMP in each vascular smooth muscle.

Amrinone

Glucagonlike peptide-1(7-36)amide suppresses glucagon secretion and decreases cyclic AMP concentration in cultured In-R1-G9 cells.

We previously reported that GLP-1(7-36)amide had glucagonostatic action as well as insulinotropic action in the perfused rat pancreas. In this study, we examined the effect of GLP-1(7-36)amide on glucagon secretion and cAMP concentration in glucagon-secreting cell line, In-R1-G9. GLP-1(7-36)amide (1nM) significantly suppressed glucagon secretion and decreased cAMP concentration in the cells. GLP-1(1-37) did not affect glucagon secretion. It is suggested that inhibitory effect of GLP-1(7-36)amide on glucagon secretion is at least partly mediated by adenylate cyclase system.

1-Methyl-3-isobutylxanthine

Prostacyclin administration suppresses the increase in hepatic levels of COL1A(I) and glyceraldehyde-3-phosphate dehydrogenase mRNAs in the rat treated with carbon tetrachloride.

Northern analysis using total RNAs from the component cells of normal rat liver indicated that COL1A(I) mRNA is present in fat-storing cells (Ito cells) and sinusoidal endothelial cells. A fraction for Kupffer cells also contained this mRNA. When CCl4 was given, COL1A(I) mRNA was increased in a factor of 1.5 in the fractions of these component cells. After 48 h of the drug administration, hepatocytes appeared to possess over 60% of liver COL1A(I) mRNA, although in normal hepatocytes its level was below the range detectable by our procedures. Under this injured condition of liver, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA level was elevated, while activity of this enzyme was lowered by 50% of the control value. All the changes were obviously suppressed by the simultaneous administration of prostacyclin.

Animals

Time-resolved fluorometry of purple membrane of Halobacterium halobium. O640 and an O-like red-shifted intermediate Q.

The photocycle of the light-adapted purple membrane was studied with a time-resolved fluorometry apparatus: fluorescence of the sample suspension (greater than 660 nm) was pumped with a 633-nm cw laser and the temporal change induced by a 532-nm pulsed laser was measured with a photon-counting-type transient recorder. The formation and the decay of the O640 intermediate were clearly observed in the pH region between 4.0 and 11.4. A photochemical cycle of N560 was apparently driven in alkaline suspension (pH greater than 9.3). An O-like fluorescent intermediate Q appears and decays with time constants of less than 0.1 ms and 1.7 +/- 0.2 ms, respectively.

Bacteriorhodopsins

[A case with delayed-onset radiation pneumonitis suspected to be induced by oral etoposide].

Radiation pneumonitis usually occurs within 1-3 months after the completion of radiation therapy. A 63-year-old male with primary lung cancer treated by radiation therapy developed radiation pneumonitis 5 months after the completion of radiation therapy. He received 60 Gy to the lung tumor in a conventional fractionation schedule, and then two courses of intravenous chemotherapy using cis-diamine-dichloroplatinum (II) (110-140 mg) and etoposide (140-175 mg). Oral etoposide was initiated for bone metastases on the 104th day after the completion of radiation therapy at a daily dose of 20 mg, to a total dose of 1075 mg. He complained of fever and exertional dyspnea 5 months after the completion of radiation therapy. Chest radiography showed homogeneous infiltrates in the irradiated lung. These clinical signs and symptoms were refractory to antibiotic therapy, but steroid therapy resulted in marked improvement. The development of radiation pneumonitis was suspected to be induced by oral etoposide, which was given before the onset of radiation pneumonitis. These data suggest that etoposide induces a recall phenomenon, as has been demonstrated with such drugs as adriamycin and actinomycin-D.

Administration, Oral

[Temperature distribution and geometry of the electrodes in RF interstitial hyperthermia using circular and interstitial electrodes].

To evaluate the feasibility of clinical application of a newly developed interstitial hyperthermia system, which consists of an 8 MHz radiofrequency generator, interstitial needle electrodes, and a superficial circular electrode, we conducted preclinical experiments using an agar phantom and VX-2 carcinoma in the rabbit. In the experiment with an agar phantom, four 4 cm needle electrodes were placed in a square array at intervals of 1.0, 1.5, and 2.0 cm. Thermography demonstrated homogeneous temperature distribution at electrode intervals of 1.0 and 1.5 cm, but hot spots around the electrodes at an interval of 2.0 cm. When electrode deviation was less than 8 degrees from the parallel plane, no temperature deviation was observed. Using two 2 cm electrodes and two 4 cm electrodes in square array, thermography demonstrated a homogeneous temperature distribution in the area surrounded by the electrodes. Even if the electrodes were located at the periphery of the agar phantom, a homogeneous temperature distribution was obtained in the area surrounded by the electrodes. Using four 4 cm electrodes at intervals of 1.5 cm in VX-2 carcinoma in the rabbit, ideal heating was obtained: 42 degrees C at the periphery of the tumor and 43 degrees C at the center. These data suggest that the newly developed interstitial hyperthermia apparatus provides homogeneous heat distribution at electrode intervals of 1.5 cm or less and can be used in a Phase I study for deep-seated or superficial tumors.

Animals

[Radiation therapy for patients with obstructive jaundice caused by carcinoma of the extrahepatic biliary system].

From February 1980 through September 1990, 92 patients with obstructive jaundice resulting from biliary tract cancer registered at Shikoku Cancer Center Hospital or Ehime University Hospital. Radiation therapy (RT) was used to treat 38 of these patients (30 with carcinoma of the extrahepatic bile duct, excluding ampulla of Vater, and eight patients with carcinoma of the gallbladder). Of 38 patients, 11 underwent intraoperative radiation therapy (IORT), and 27 were treated by external radiation therapy (ERT) alone. In contrast, 54 patients (39 with carcinoma of the extrahepatic bile duct and eight with carcinoma of the gallbladder) were not treated by RT. All jaundiced patients received external and/or internal biliary drainage of some kind. Among patients undergoing biliary drainage with a catheter, 21 patients who underwent RT (four with IORT) survived significantly longer than 19 patients who did not (generalized Wilcoxon test: p less than 0.05). There were no significant differences in survival between 7 patients with recanalization and 11 patients with no recanalization. Concerning the survival of laparotomized patients, excluding those with complete resection or perioperative death, eight patients treated with postoperative ERT survived longer than 12 patients who did not have postoperative ERT (not significantly). Eleven patients underwent IORT. A patient with unresectable carcinoma of the hilar bile duct survived 2 years and 3 months after a combination treatment of ERT and IOTR. In four of eight autopsied patients, radiation effects of Grade II were observed (Oboshi and Shimosato's evaluation system for the histological effects of radiation therapy). Our experience suggests that RT is effective in patients with obstructive jaundice caused by carcinoma of the biliary system.

Adenocarcinoma

Screening of organophosphorus pesticides using liquid chromatography-atmospheric pressure chemical ionization mass spectrometry.

Screening and identification of organophosphorus pesticides in blood from patients suffering from acute agricultural chemical toxicity were established by a liquid chromatography-atmospheric pressure chemical ionization mass spectrometric method. To determine 21 pesticides, it was necessary to monitor both positive and negative ions. This method could easily screen for 21 organophosphorus pesticides in less than 30 min. By comparison with a gas chromatographic-mass spectrometric method, the chemicals indicated a similar extent of specificity and within equivalent detection limits, thus satisfying clinical requirements completely.

Chromatography

[Results of radiation therapy for squamous cell carcinoma of the uterine cervix using high dose-rate intracavitary irradiation].

We retrospectively analyzed 216 previously untreated patients with cervical cancer treated by high dose-rate intracavitary irradiation between 1978 and 1986. Cumulative 5-year survivals in stage Ib, IIa, IIb, IIIa, IIIb and IVa were 72.3%, 88.9%, 68.9%, 75.0%, 64.0% and 16.7%, respectively. Cause-specific 5-year survivals in stage Ib, IIa, IIb, IIIa, IIIb and IVa were 93.3%, 88.9%, 74.7%, 75.0%, 68.9%, and 18.8%, respectively. Recurrences outside the pelvis in stage IIb and IIIb (14.9% and 24.0%) were more common than loco-regional recurrences (10.3% and 12.0%). However, loco-regional recurrences (50%) were most frequent in stage IVa. Thirteen patients (6.0%) required surgical management for intestinal complications (severe). Six patients (2.7%) died due to intestinal complications (fatal). These fatal and severe complications were closely correlated with the dose of external radiation. These data suggest that intracavitary irradiation using a high dose-rate system is useful for the treatment of uterine cancer; however, further efforts to reduce intestinal complications by lowering the dose of external radiation will be necessary. It is also suggested that a combined modality, such as chemotherapy, is necessary for controlling metastases outside the pelvis in stage IIb and IIIb, and for local control in stage IVa.

Adult

Cyclosporin reduces proteinuria in rats with aminonucleoside nephrosis.

The effect of cyclosporin (CS) was assessed in Sprague-Dawley rats with puromycin aminonucleoside (PA) nephrosis induced by a single intraperitoneal injection of PA. Three groups of rats were injected intraperitoneally with CS (10 mg/kg body weight) daily, beginning 1 day before PA administration, or 5 or 10 days after PA administration, for 10 days. CS significantly reduced proteinuria in rats with PA nephrosis in comparison with untreated nephrotic controls. After discontinuation of the CS treatment, proteinuria gradually increased, reaching values similar to those in control nephrotic rats. CS pretreatment did not prevent the induction of PA-induced nephrotic syndrome. Light microscopy and assessment of anionic sites in the glomerular basement membrane revealed no differences between normal rats, nephrotic controls, and CS-treated rats. These results show that CS can reduce proteinuria in PA nephrosis, but cannot ameliorate the glomerular changes.

Animals

Chum salmon (Oncorhynchus keta) stanniocalcin inhibits in vitro intestinal calcium uptake in Atlantic cod (Gadus morhua).

Chum salmon (oncorhynchus keta) stanniocalcin was purified, partially identified and tested for bioactivity in an assay on the intestinal calcium uptake in a marine teleost (Gadus morhua). Basic ethanol extraction, ion exchange chromatography, gel filtration and reverse-phase high-performance liquid chromatography resulted in the isolation of a homogeneous glycoprotein that appears as a 46-kDa product under nonreducing conditions and as a 23-kDa product under reducing conditions after sodium dodecylsulphate-polyacrylamide gel electrophoresis. The glycoprotein is likely to be a homodimer composed of two subunits of 23 kDa each. Further characterization indicates homology to Australian eel, sockeye salmon, coho salmon and rainbow trout stanniocalcin, and the glycoprotein is thus concluded to be stanniocalcin. Stanniocalcin-like immunoreactivity was demonstrated in the corpuscles of Stannius of the Atlantic cod, with a specific antiserum raised against purified chum salmon stanniocalcin. The physiological importance and the biological activity of chum salmon stanniocalcin was tested by evaluating its effect on intestinal calcium uptake by the Atlantic cod in vitro. The intestine was perfused, both vascularly and through the intestinal lumen, and the calcium mucosa-to-serosa flux was measured using 45Ca2+ as a tracer. Stanniocalcin decreased the intestinal calcium uptake in a dose-related manner by 13.5% and 22.4% at doses of 2.2 and 10.9 nM stanniocalcin, respectively. The results establish the intestine as a target organ for stanniocalcin in marine teleosts.

Amino Acid Sequence

Damage of cultured chondrocytes by hydrogen peroxide derived from polymorphonuclear leukocytes: a possible mechanism of cartilage degradation.

To study the mechanisms of chondrocyte damage, chondrocyte cytotoxicity as shown by chromium-51 release induced by polymorphonuclear leukocytes (PMNLs) was examined. PMNLs significantly enhanced chondrocyte cytotoxicity in the presence of phorbol dibutyrate. This chondrocyte damage was abolished by the addition of catalase, whereas superoxide dismutase and scavengers of hydroxyl radicals and protease inhibitors failed to reverse it. When cartilage matrix components such as hyaluronic acid and various proteoglycans were added to the PMNL-chondrocyte cultures, these components failed to affect the chromium-51 release. These results suggest that the increase in chondrocyte cytotoxicity is due to hydrogen peroxide generated by the PMNLs, and that cartilage matrix components do not prevent it. Hydrogen peroxide from PMNLs may therefore play an important role in cartilage degradation through direct damage of chondrocytes during inflammatory process.

Animals