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S Ueda

Publications and source records attributed to S Ueda.

At least 829 records · Page 46Linked to original sources

[The study of drug sensitivity on newly established three choriocarcinoma cell lines].

After serial transplantation in nude mice, we had established three new human choriocarcinoma cell lines (NaUCC-1,2 and 3). These three cell lines and BeWo were examined for sensitivity to Act-D, MTX and the combined agents (Act-D + MTX) 3H-Act-D uptake and 3H-MTX uptake, and were compared for each treatment. NaUCC-1 showed low sensitivity to MTX (p less than 0.05), but showed high sensitivity to Act-D (p less than 0.05). BeWo showed low sensitivity to Act-D (p less than 0.05). In examining sensitivity to the combined agents (Act-D+ MTX), the sensitivity of NaUCC-2 to Act-D was decreased (p less than 0.05) by MTX added at the same time. In the 3H-Act-D uptake experiment, NaUCC-1 did uptake a relatively larger amount of 3H-Act-D (p less than 0.01) and BeWo a smaller amount of it (p less than 0.05). In the 3H-MTX uptake experiment, NaUCC-1 did uptake a relatively smaller amount of 3H-MTX (p less than 0.05), but NaUCC-2 uptook a larger amount of it (p less than 0.005). NaUCC-1 established from the patient in whom tumor cells were resistant to treatment, had a low response to MTX. NaUCC-2 was established from the patient in whom it was found that MTX inhibits the Act-D effect on tumor cells. In the study of combined agents in NaUCC-2, the growth inhibition effect of Act-D was suppressed by the MTX added.

Animals↗

The contractile action of palytoxin in the isolated rabbit urinary bladder.

Palytoxin at 10(-10)-10(-7) M caused contractions of the detrusor muscle from rabbit urinary bladder in a concentration-dependent manner. The response to palytoxin was markedly inhibited by indomethacin (a cyclooxygenase inhibitor) or nordihydroguaiaretic acid (a lipoxygenase inhibitor) at 10(-5) M. Indomethacin and nordihydroguaiaretic acid also inhibited the response to arachidonic acid at 10(-3) M. A Ca2+-free medium with EGTA or nifedipine at 10(-5) M, nearly abolished the responses to palytoxin and arachidonic acid. Tetrodotoxin, phentolamine, atropine and chlorpheniramine (all at 10(-5) M) had a slight or no inhibitory effect on the response to palytoxin. These results suggested that in the rabbit bladder, the contractile effect of palytoxin is mainly dependent on an increase in metabolites of arachidonic acid.

Acrylamides↗

Identification of neuropeptide Y immunoreactivity in the suprachiasmatic nucleus and the lateral geniculate nucleus of some mammals.

The distribution of neuropeptide Y (NPY) immunoreactivity in the suprachiasmatic nucleus (SCN) and the lateral geniculate nucleus (LGN) of 5 kinds of mammals was studied using the peroxidase-anti-peroxidase method. In the SCN of the rat, hamster, chipmunk and cat, NPY-immunoreactive fibers were detected, particularly in the ventral part. In the 3 rodents and the cat, the somata and fibers of NPY-immunoreactive neurons were observed in the LGN. However, immunoreactive structures were not found in the SCN or LGN of the monkey. These results indicate that NPY immunoreactivity in the monkey LGN-SCN tract is absent.

Animals↗

Synchronous oscillation of the cytoplasmic Ca2+ concentration and membrane potential in cultured epithelial cells (Intestine 407).

Cultured epithelial Intestine 407 cells exhibit regular oscillations of the membrane potential with repeated hyperpolarizations. These hyperpolarizations were inhibited not only by K+ channel blockers (tetraethylammonium and nonyltriethylammonium) but also by inhibitors of the Ca2+-activated K+ channel (quinine and quinidine). Using Ca2+-selective microelectrodes, cyclic increases in the cytosolic free Ca2+ concentration of more than 1 X 10(-6) M were found to coincide with the cyclic membrane hyperpolarizations. Thus, it appears that the potential oscillation is brought about by the oscillation of the intracellular free Ca2+ level which induces periodic activation of the Ca2+-dependent K+ channels. Neither the deprivation of extracellular Ca2+ nor the application of Ca2+ channel blockers (Co2+ and Ni2+) abolished the potential oscillation. Mitochondrial inhibitors (KCN, NaN3, antimycin A, FCCP and dinitrophenol) inhibited the potential oscillation, whereas glycolytic inhibitors (iodoacetic acid and NaF) had no effects. Caffeine and oxalate, which affect the microsomal Ca2+ transport, failed to exert any effect upon the potential oscillation. It is concluded that the cytosolic Ca2+ oscillation results from cyclic releases of Ca2+ from the intracellular storage site, which depends upon mitochondrial activities.

Animals↗

Experimental systemic amyloidosis induced by immunization with syngeneic organ extracts in mice.

Systemic amyloidosis was induced consistently in mice by intramuscular injection of syngeneic organ (liver and kidney) extracts mixed with CFA six times at weekly intervals. Syngeneic organ extract with CFA also induced amyloidosis of a lesser degree. All three strains of mice (C57BL/6, C3H/He, and BALB/c) injected with a syngeneic liver extract mixed with CFA developed systemic amyloidosis; the most prominent amyloid deposition occurred in C57BL/6 (B6) mice, followed by C3H/He and BALB/c. The amyloid substance deposited in these animals was identified as mouse amyloid A protein (AA). Furthermore, an organ specificity of the immunogen in inducing amyloidosis was suggested with liver and kidney extracts. Primed spleen cells of the immunized B6 mice were fractionated by a nylon-wool column and injected to normal recipient mice via the tail vein. Organs of the recipient mice developed systemic amyloidosis 8 wk after the transfer, and the most prominent histological changes occurred in the recipient mice given nylon-wool column adherent spleen cells. Using anti-Thy-1,2; Ly-1; Ly-2, antibody and complement, it was suggested that T cells, especially Ly-1,2,3+ T cell populations in the primed nylon-wool adherent cells, play an important role in the induction of systemic amyloidosis. It was shown further that the amyloidosis-inducing substance in liver extract was composed of unstable proteins or protein-bound substance.

Amyloidosis↗

Isolation and characterization of two isozymes of myosin heavy chain from canine atrium.

To clarify the characteristics of myosin isozymes in the atrium, we fractionated two isoforms of myosin heavy chain (HC), atrial HC alpha (A-HC alpha) and HC beta (A-HC beta), from the canine heart by affinity chromatography, using monoclonal antibodies specific for HC alpha (CMA19) and HC beta (HMC50), respectively, and then compared their peptide composition and enzymatic properties with those of ventricular HC alpha (V-HC alpha) and HC beta (V-HC beta). The reactivity of these isozymes with three monoclonal antibodies revealed that there are at least three different epitopes between A-HC alpha and A-HC beta. Differences in the primary structure of A-HC alpha and A-HC beta were confirmed by one- and two-dimensional gel electrophoretic analyses of these peptides, produced by digestion with alpha-chymotrypsin and cyanogen bromide (CNBr). A-HC alpha and V-HC alpha were indistinguishable proteins, and A-HC beta was also very similar to V-HC beta. Furthermore, there were differences between A-HC alpha and A-HC beta in their Ca2+-activated ATPase activities. The ATPase activity of A-HC beta was lower than that of A-HC alpha and was similar to that of V-HC beta. We concluded that there are two different isozymes of myosin heavy chain in the atrium (A-HC alpha and A-HC beta), as well as in the ventricle (V-HC alpha and V-HC beta), and that A-HC beta is very similar to V-HC beta, the predominant form of ventricular myosin, in its molecular structure and enzymatic activity.

Adenosine Triphosphatases↗

The augmentation of tumor-specific immunity by virus help. III. Enhanced generation of tumor-specific Lyt-1+2- T cells is responsible for augmented tumor immunity in vivo.

The role of vaccinia virus-reactive helper T cells (Th) in augmenting in vivo generation of antitumor protective immunity and the Ly phenotype mediating the enhanced in vivo tumor immunity were investigated. C3H/HeN mice were inoculated i.p. with viable vaccinia virus to generate vaccinia virus-reactive Th activity. The mice were subsequently immunized i.p. with virus-infected syngeneic X5563 and MH134 tumor cells, and spleen cells from these mice were tested for in vivo tumor neutralizing activity. Immunization of virus-primed mice with virus-uninfected tumor cells and of virus-unprimed mice with virus-infected tumor cells failed to result in in vivo protective immunity. In contrast, spleen cells from mice immunized with virus-infected tumor cells subsequent to virus-priming exhibited potent tumor-specific neutralizing activities. Such an augmented generation of in vivo protective immunity was accompanied by enhanced induction of tumor-specific cytotoxic T lymphocyte (CTL) and antibody activities in X5563 and MH134 tumor systems, respectively. However, analysis of the effector cell type responsible for in vivo tumor neutralization revealed that enhanced in vivo immunity was mediated by Lyt-1+2- T cells in both tumor systems. Moreover, the Lyt-1+2- T cells exerted their function in vivo under conditions in which anti-X5563 tumor-specific CTL or anti-MH134 tumor-specific antibody activity was not detected in recipient mice. These results indicate that augmenting the generation of a tumor-specific Lyt-1+2- T cell population is essential for enhanced tumor-specific immunity in vivo.

Animals↗

Feasibility of UV-inactivated vaccinia virus in the modification of tumor cells for augmentation of their immunogenicity.

We compared the immunity induced by tumor cells modified with UV-inactivated purified vaccinia virus (UV-VV) and with live purified vaccinia virus (L-VV). C3H/HeN mice were inoculated i.p. with UV-VV or L-VV after whole-body irradiation with 150 rads of X-rays (priming). After 3 weeks the mice were immunized i.p. 3 times at weekly intervals with syngeneic X5563 or MH134 cells that had been absorbed in vitro with UV-VV or infected with L-VV and subsequently irradiated with 10(4) rads of X-rays. Then 1 week after the last immunization, the mice were challenged s.c. with X5563 viable tumor cells or challenged i.p. with MH134 viable tumor cells. The 50% lethal dose (TLD50) of X5563 in mice primed and immunized with UV-VV (UV-VV group) on s.c. challenge (10(6.06)) was the same as for mice treated with L-VV (L-VV group), whereas the TLD50 of unprimed or nonimmunized mice (control group) was 10(2.61). The TLD50 of MH134 in the UV-VV treated group on i.p. challenge (10(6.48)) was similar to that of the L-VV treated group (10(6.54)), while the TLD50 of the control group was 10(1.00). The difference between the TLD50 values of X5563 on s.c. challenge of mice primed and immunized with UV-VV or L-VV and control mice was 10(3.4). The difference between the TLD50 values of MH134 on i.p. challenge of primed and immunized mice and control mice was 10(5.5). These results indicate that the in vivo helper function of UV-VV is similar to that of L-VV and that the augmenting effect of this protocol depends on the kind of tumor.

Allantois↗

Distributional pattern of serotonin-immunoreactive nerve fibers in the lateral geniculate nucleus of the rat, cat and monkey (Macaca fuscata).

The distribution of serotonin-containing nerve fibers in the lateral geniculate nucleus (LGN) of the rat, cat, and monkey (Macaca fuscata) was studied by use of the peroxidase-antiperoxidase method and an antiserum against serotonin. In all three species, the pattern of fibers was denser in the ventral portion of the LGN (LGNv) than in the dorsal nuclear portion (LGNd). In the LGNd of rat, serotonin-immunoreactive fibers were evenly distributed in the form of a dense network, but in cat and monkey there were marked regional differences. Serotonin-immunoreactive elements were most numerous in the C complex and medial interlaminal nucleus of cat, and in the S layer and interlaminar zones of Macaca fuscata.

Animals↗

Fetal origin of the medulloblastoma: evidence from growth analysis of two cases.

Growth analysis of medulloblastomas was performed in two children. They initially manifested symptoms at the age of 3 years and 9 months and at the age of 2 months respectively. Computerized tomography (CT) scans were obtained at different points in each case. The growth curves were drawn on a semilogarithmic graph by calculating the tumor volume on CT on the assumptions that the tumor started from a single tumor cell and that the growth rate was constant. By extrapolating the curves back, tumor inception was estimated to have occurred respectively at the 14-23rd week and at the 16-17th week of gestation. Additional cell kinetic data were obtained from DNA analysis of surgical pathology specimens. Calculated cell-cycle times were 22-32 h for both cases. The S phases comprised 26.3% and 27% and the G0G1 phases 66.8% and 62% of the cell cycle, respectively, for case 1 and 2. Assuming a labelling index of 14%, the cell loss factors were estimated to be 97% and 74% (case 1 and case 2 respectively). The seventeenth week of gestation in humans corresponds to the timing of events occurring postnatally at days 3-18 in the developing cerebella of rodents, i.e., at the time of maximal activity in the migration and differentiation of the cells of the fetal external granular layer. Medulloblastomas have been experimentally induced in rodents by the injection of oncogenic viruses during the neonatal period, and statistical data on the epidemiology of human medulloblastomas have suggested a possible association with the contamination of polio vaccine by the SV 40 virus.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Cycle↗

Polypeptide analysis with monoclonal antibodies of A type inclusion bodies induced by cowpox virus.

The antigen in A type inclusion bodies (ATIB) induced by cowpox virus (CPV) was examined by immunofluorescent staining with monoclonal antibodies and polypeptide analysis. In the immunofluorescence (IF) test, these monoclonal antibodies reacted only with cytoplasmic inclusion bodies in cells infected with CPV. The fluorescence became detectable in the cells 6-9 hours after infection with CPV. No fluorescence was detectable in cells infected with CPV in the presence of cytosine-I-beta-D-arabinofuranosyl-HCl (Ara C) or in cells infected with other poxviruses, such as vaccinia virus (VV) or Shope fibroma virus (SFV). On Western blotting and immunoprecipitation followed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), only one component with a molecular weight of about 160,000 (160 K) was detected in CPV-infected cells. This 160 K polypeptide was first detectable 12 hours after infection of cells with CPV, and was not detectable in infected cells in the presence of Ara C. The 160 K polypeptide was not detected in cells infected with VV or SFV, or in virions purified from CPV-, VV- or SFV-infected cells.

Animals↗

Cross-reactivity among cowpox, ectromelia and vaccinia viruses with monoclonal antibodies recognizing distinct antigenic determinants in A-type inclusion bodies.

Several monoclonal antibodies recognizing distinct antigenic determinants in A-type inclusion bodies (ATIB) induced by cowpox virus (CPV) were obtained to examine the cross-reactivity among various strains of poxviridae, comprising CPV, ectromelia virus (EV), vaccinia virus (VV) and Shope fibroma virus (SFV). The monoclonal antibodies were classified into at least 3 groups on the basis of the results of an immunofluorescence test and immunoblotting; i. e., strain-specific, CPV and EV-specific and Orthopoxvirus (CPV, EV and VV)-specific antibodies. Differences were found between the antigenic determinants of ATIB of LB strains (LB red and LB white) and other strains (Amsterdam, 53, 58 and 60) of CPV and also between those of ATIB of CPV and EV. An interesting finding was that VV also produces the antigen analogous to that associated with ATIB in CPV- and EV-infected cells despite the absence of morphologically defined ATIB.

Antibodies, Monoclonal↗

Oscillations of cytoplasmic concentrations of Ca2+ and K+ in fused L cells.

Using Ca2+- and K+-selective microelectrodes, the cytosolic free Ca2+ and K+ concentrations were measured in mouse fibroblastic L cells. When the extracellular Ca2+ concentration exceeded several micromoles, spontaneous oscillations of the intracellular free Ca2+ concentration were observed in the submicromolar ranges. During the Ca2+ oscillations, the membrane potential was found to oscillate concomitantly. The peak of cyclic increases in the free Ca2+ level coincided in time with the peak of periodic hyperpolarizations. Both oscillations were abolished by reducing the extracellular Ca2+ concentration down to 10(-7) M or by applying a Ca2+ channel blocker, nifedipine (50 microM). In the presence of 0.5 mM quinine, an inhibitor of Ca2+-activated K+ channel, sizable Ca2+ oscillations still persisted, while the potential oscillations were markedly suppressed. Oscillations of the intracellular K+ concentration between about 145 and 140 mM were often associated with the potential oscillations. The minimum phase of the K+ concentration was always 5 to 6 sec behind the peak hyperpolarization. Thus, it is concluded that the oscillation of membrane potential results from oscillatory increases in the intracellular Ca2+ level, which, in turn, periodically stimulate Ca2+-activated K+ channels.

Animals↗

Estrogen effects on plasma volume, arterial blood pressure, interstitial space, plasma proteins, and blood viscosity in sheep.

In adult castrated ewes the infusion of 17 beta-estradiol for 3 weeks was associated with a 12% increase in body weight, a 20% increase in whole blood volume (mainly due to a 27% increase of plasma volume), a 13% decrease in mean arterial blood pressure, and a 40% increase in heart rate. The change in plasma volume correlated with the change in estradiol concentration (r = 0.72). Most of the fluid was retained in the interstitial space, as represented by a 6 kg weight gain, 10% of which was in the intravascular compartment. Whole blood and plasma viscosity increased 16% and 21%, respectively, thus reversing some of the blood volume effects toward a hyperdynamic cardiovascular state. We conclude that many of the cardiovascular and hematologic changes with estrogen administration are similar to the changes observed during pregnancy, with the proposed requirement of decrease in mean arterial blood pressure as a condition for blood volume expansion.

Animals↗

Potent alpha-adrenoceptor blocking action of SGB-1534, a new quinazoline antihypertensive agent in vitro experiments.

SGB-1534 inhibited the contractile response to norepinephrine (NE), methoxamine (MO) and electrical transmural stimulation in the rabbit aorta, basilar and cat coronary arteries and only in the rabbit aorta its inhibitor action was a competitive manner. In the rabbit aorta, the potency (pA2) of SGB was greater than that of prazosin, whereas in the other preparations, the effect of SGB was comparable to that of prazosin. In the rabbit aorta, both SGB and prazosin abolished the contraction induced by transmural stimulation. In the guinea-pig vas deferens, SGB failed to affect the inhibitory effect of clonidine on the response to electrical field stimulation. SGB had no inhibitory effects on the contractile response to potassium, 5-hydroxytryptamine, PGF2 alpha and an excess Ca2+ and the relaxing response to isoproterenol in the vascular tissues. In the electrically driven left atria of guinea-pigs, SGB had no effect on the electromechanical parameters and the isoproterenol induced inotropic effect. On the specific binding of [3H]prazosin in the rabbit aorta, the inhibitory effect of SGB was greater than that of prazosin and phentolamine.

Adrenergic alpha-Antagonists↗

Pseudohyperaldosteronism (Liddle's syndrome): a case report.

A 22-year-old man was hospitalized because of hypertension, hypokalemic alkalosis and suppressed plasma renin activity. Although these findings were similar to hyperaldosteronism, plasma aldosterone concentration and urinary aldosterone excretion were lower than the normal range. Adrenocortical function also was normal except for aldosterone. Treatment with spironolactone, salt restriction and potassium supplementation improved the hypokalemia but not the hypertension. Blood pressure decreased markedly after administration of triamterene.

Adrenal Cortex Hormones↗

Experimental gold nephropathy in guinea pigs: detection of autoantibodies to renal tubular antigens.

Renal tubular dysfunction was induced in Hartley guinea pigs by injection of sodium aurothiomalate (gold) as manifested by excretion of tubular basement membrane (TBM) antigen and renal tubular epithelial (RTE) antigen in urine and tubular proteinuria. Following the tubular dysfunction, autoimmune tubulointerstitial nephritis (TIN) and/or immune complex nephropathy (ICN) developed in a large proportion of animals. TIN was associated with anti-TBM antibodies, and the histological features were characterized by tubular lesions with interstitial mononuclear cell infiltration, destruction of tubules, and interstitial fibrosis. In ICN, the glomerular lesions consisted of partial thickening of capillary walls and mesangial cellularity, and granular immune deposits were seen in the mesangial area and on capillary walls. Furthermore, electron-dense deposits were demonstrated in the mesangial area and in the glomerular basement membrane (GBM) by electron microscopy. Anti-RTE antibodies were detected in the sera and eluates from the kidney of animals with ICN. RTE antigens were also detected in the glomerular deposits by indirect immunofluorescence using anti-guinea pig RTE antibody. These results suggest that TBM and RTE antigens released from renal tubules damaged by a direct toxic action of gold may lead to antibody formation against these antigens and induce TIN and/or ICN.

Animals↗