Allergic contact dermatitis from para-tertiary-butylphenol-formaldehyde resin (PTBP-F-R).
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
Y Ogino
Publications and source records attributed to Y Ogino.
Enhancement of thrombin receptor activation by thrombin receptor-derived heptapeptide with para-fluorophenylalanine in place of phenylalanine.
Thrombin receptor-derived peptide SFLLRNP (one-letter amino acid code) which corresponds to the N-terminal heptapeptide of tethered ligand is able to activate thrombin receptor and to stimulate the phosphoinositide (PI) turnover. The replacement of Phe-2 by Ala eliminated this activity completely, showing the crucial role of the Phe-phenyl group in receptor activation. It was found that substitution of para-fluorophenylalanine ((p-F)Phe) for Phe-2 enhanced several times the PI-turnover activity of SFLLRNP. This is the first example to date of a substitution with one order of magnitude greater increase in receptor activation. The Phe-2/Tyr substitution diminished the activity drastically (almost 2% of SFLLRNP), indicating the importance of hydrophobicity of Phe2-phenyl. The Phe-2/Leu substitution, however, diminished also the activity (less than 2% of SFLLRNP). These results suggested that highly specific hydrophobic interaction exists between Phe-2 of the tethered ligand and its binding site in thrombin receptor.
Amino Acid Sequence↗
[The histochemical study of the effects of estrogen on the forebrain cholinergic neurons of fetal female rats transplanted into the anterior eye chamber of adult female rats].
In order to clarify the effects of estrogen on cholinergic basal forebrain neurons, a cholinergic neuron in the diagonal band nucleus of the female fetal rat was implanted into the anterior eye chamber of the female adult rat. Some host rats were treated with 2mg estradiol valerate (E2v) injected every 3 days after ovariectomy while others were not 2 and 4 weeks after transplantation, the growth of cholinergic neurons in the graft was studied using acethylcholinesterase (AChE) histochemistry. At 2 weeks after transplantation, AChE positive neurons and fibers were densely distributed in the grafts of E2v treated rats. Also in grafts without E2v treatment, AChE positive neurons and fibers were found in all the grafts although their density was low. At 4 weeks, AChE staining was dense staining observed in both groups. These results indicate that neurotrophic effect of estrogen on the cholinergic basal forebrain neurons.
Acetylcholinesterase↗
Thrombin is a regulator of astrocytic endothelin-1.
Endothelin-1, a potent vasoconstrictor of cerebral vessels, is produced by rat primary astrocytes and is subject to autostimulatory regulation in these cells. In this study we examined the effect of thrombin on astrocytic endothelins and report that endothelin-1 is released into the culture fluid in response to thrombin treatment. However, increased production of endothelin-1 is not accompanied by a concomitant increase in steady-state levels of endothelin-1 mRNA as assessed by reverse transcriptase-polymerase chain reaction, even though thrombin stimulation leads to increased inositolphospholipid turnover and activation of the nuclear factor AP1. Thus, astrocytic production of endothelin-1 may be mainly post-transcriptionally regulated in response to thrombin stimulation. In addition, two endothelin receptor genes (ET(A) and ETB) were found to be transcribed simultaneously in primary astrocyte cultures, and both thrombin and endothelin-1 stimulation result in a distinct temporary decrease in ET(A) mRNA. These studies suggest a role for thrombin in the regulation of brain perfusion through astrocytic endothelin-1 expression.
Animals↗
Fixed drug eruption due to allylisopropylacetylurea.
We report a case of fixed drug eruption due to allylisopropylacetylurea. A 21-year-old female developed purplish-red round eruptions on her neck and left thigh after taking an analgesic containing isopropylantipyrine, allylisopropylacetylurea, phenacetin and anhydrous caffeine. Patch testing with the analgesic and its ingredients on the eruptive area showed positive reactions to the analgesic and allylisopropylacetylurea, while patch testing on the non-eruptive area showed negative reactions. We diagnosed her condition as a fixed drug eruption due to allylisopropylacetylurea in an analgesic.
Adult↗
Thrombin is the major serum factor stimulating phosphoinositide turnover, but not DNA synthesis in human neuroblastoma SH-EP cells.
Fetal calf serum stimulates both phosphoinositide turnover and DNA synthesis in SH-EP cells. The phosphoinositide turnover-stimulating activity of serum is largely (70%) reduced in the presence of hirudin, a blocker of thrombin activity. Yet, hirudin does not alter the ability of serum to stimulate DNA synthesis. Purified alpha-thrombin is a potent (EC50, 35 pM) stimulator of phosphoinositide turnover in SH-EP cells, but induces DNA synthesis only at much higher concentrations (10 nM-1 microM). Thus, serum thrombin accounts for most of the ability of serum to stimulate phosphoinositide hydrolysis, but not for the effect of serum on cell division, since the concentration of thrombin in serum is not sufficient to induce DNA synthesis. These data suggest that hydrolysis of inositol lipids may not be the main signalling event mediating the mitogenic effects of alpha-thrombin.
Blood↗
Estrogen as a growth factor to central nervous cells. Estrogen treatment promotes development of acetylcholinesterase-positive basal forebrain neurons transplanted in the anterior eye chamber.
In a previous report, we demonstrated in vivo ameliorating effects of conjugated estrogen in women suffering from senile dementia-Alzheimer's type. To investigate the effects of estrogen on the growth of cholinergic neurons, the present study was performed using rat cholinergic tissue implanted into the anterior chamber of the eye. Fetal diagonal band tissue containing cholinergic neurons was grafted into the anterior eye chamber of adult female rats that had either been treated or not with 2 mg estradiol valerate injected every 3 days after oophorectomy. Two and four weeks after transplantation, the axonal and/or dendritic growth of cholinergic neurons in the graft was studied using acetylcholinesterase histochemistry. At both times, acetylcholinesterase positive processes were densely distributed in the grafts of estradiol valerate treated rats, while in rats without estradiol valerate treatment acetylcholinesterase positive reaction was essentially localized only on the cell bodies. These findings were more obvious at 2 weeks after transplantation than at 4 weeks. These results suggest that estrogen acts on cholinergic neurons as a growth factor.
Acetylcholinesterase↗
The epithelial phenotype of human neuroblastoma cells express bradykinin, endothelin, and angiotensin II receptors that stimulate phosphoinositide hydrolysis.
The neuroblastoma line SK-N-SH consists of distinct and interconverting cell types, which include a neuroblast phenotype (SH-SY5Y), an epithelial phenotype (SH-EP), and an intermediate cell type (SH-IN). In SH-SY5Y cells, only muscarinic receptor activation produced stimulation of phosphoinositide turnover, whereas in SH-EP cells, where muscarinic receptors are not present, the peptides bradykinin, endothelin, and angiotensin II stimulated phosphoinositide hydrolysis with EC50 values of 16, 6, and 0.7 nM, respectively, and a rank order of maximal effects of bradykinin greater than endothelin greater than angiotensin II. Fetal calf serum at concentrations between 1 and 10% was also a potent stimulator of phosphoinositide hydrolysis in SH-EP cells but not in SH-SY5Y cells. In the intermediate cell clone, SH-IN, phosphoinositide hydrolysis was stimulated not only by muscarinic receptors, but also by endothelin, bradykinin, and serum, an indication that this cell type harbors all the kinds of receptors that are differentially expressed in the other two cell types. The effects of the three peptides--bradykinin, endothelin, and angiotensin II--on phosphoinositide hydrolysis in SH-EP cells were additive, a result suggesting that the three kinds of receptors may activate distinct transducer proteins and/or phospholipase C subtypes. Pretreatment of intact SH-EP cells with pertussis toxin under conditions sufficient to ADP-ribosylate 90-95% of the endogenous guanine nucleotide regulatory protein substrates did not impair the ability of any of the receptors to stimulate phosphoinositide hydrolysis in any of the cell types. In contrast, short-term exposure to the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (1 microM) abolished the stimulation of phosphoinositide hydrolysis mediated by peptide receptors in SH-EP cells and partially inhibited that by muscarinic receptors in SH-SY5Y cells. Prolonged incubation of SH-EP cells with phorbol ester resulted in a recovery of receptor responsiveness, the extent and rate of which were different for each receptor type. In contrast, there was no recovery of responsiveness for muscarinic receptors in SH-SY5Y cells. The pattern of phorbol ester-mediated effects depended on the cell rather than on the receptor type. In fact, muscarinic receptor responsiveness in SH-IN, the intermediate cell type, was desensitized by and recovered from treatment with phorbol esters in a manner more similar to peptide receptors in SH-EP than to muscarinic receptors in SH-SY5Y. These data suggest that the transduction mechanisms by which distinct receptor types are coupled to phosphoinositide hydrolysis in the three cell phenotypes differ in sensitivity to feedback regulation by protein kinase C.
Angiotensin II↗
Tinuvin P in a spandex tape as a cause of clothing dermatitis.
We report a 54-year-old female with allergic contact dermatitis from 2-(2-hydroxy-5-methylphenyl)benzotriazole (Tinuvin P) in a spandex tape sewn into underwear. Tinuvin P is used as an ultraviolet light absorber for stabilizing plastics and the other organic materials against discoloration and deterioration. It is effective in protecting synthetic and natural fibers, polyesters, chlorinated polyesters, polystyrene, polyvinyls, cellulose acetate, ethyl cellulose, acrylates, dyes, waxes, detergents, cosmetic formulations, etc. Our patient developed itchy erythema on her shoulders, chest and upper back after wearing underwear for 1 night. She showed positive reactions to spandex tape sewn into the underwear. She also reacted to 2-(2-hydroxy-5-methylphenyl)benzotriazole (Tinuvin P), which was contained in the spandex. No cross-reaction to other benzotriazoles was seen.
Chromatography, Gel↗
A case of budesonide contact allergy.
Explore the source record for details and available documents.
Administration, Topical↗
Systemic contact dermatitis due to amlexanox.
Explore the source record for details and available documents.
Adult↗
Serum estradiol 17-sulphate and lipid peroxides in late pregnancy.
Estradiol 17-sulphate is readily converted to 2-OH or 4-OH estradiol 17-sulphate. The latter two strongly antagonize lipid peroxidation, which may play certain roles during pregnancy, such as pregnancy-induced hypertension. Serum estradiol 17-sulphate during mid and late pregnancy was measured using a direct radioimmunoassay without hydrolysis, and the level increased as pregnancy progressed. The levels in the sixth (20-23 weeks) and tenth months (36-39 weeks) of gestation were 1.42 +/- 0.04 nmol/l (mean +/- SD) and 3.42 +/- 1.09 nmol/l, respectively. The maternal venous levels before and at delivery and in the umbilical veins and artery were 3.38 +/- 0.83, 3.48 +/- 1.53, 4.11 +/- 1.40 and 4.30 +/- 1.81 nmol/l, respectively. The latter two values were slightly higher than the former two. Estradiol 17-sulphate in maternal venous blood began to decrease around delivery. Serum lipid peroxides were measured using the method of Yagi. Estradiol 17-sulphate and lipid peroxides showed a simple regression slope (r = -0.548, p less than 0.05) during late pregnancy. These results suggest that estradiol 17-sulphate may be converted to 2-OH or 4-OH estradiol 17-sulphate, which act as lipid peroxide scavengers during pregnancy.
Estradiol↗
Drug efficacy at guanine nucleotide-binding regulatory protein-linked receptors: thermodynamic interpretation of negative antagonism and of receptor activity in the absence of ligand.
The mutual effects that a hormonal ligand (H) and a guanine nucleotide regulatory protein (G protein) exert on each other when simultaneously occupying distinct sites of the receptor molecule (R) can be viewed as the molecular mechanism of drug efficacy. These effects are predictable on the basis of a model assuming that the ternary complex between the three partners (HRG) reaches equilibrium in the membrane [J. Biol. Chem. 255:7108-7117 (1980)]. Ligands can be classified as agonists, neutral antagonists, or negative antagonists, depending on whether they enhance, leave unchanged, or reduce, respectively, the spontaneous tendency of R to interact with G. Using this model and the assumption that the G protein response observed in membranes reflects the sum of ligand-independent (RG) and ligand-dependent (HRG) receptor-G protein complexes, we can explain virtually all the phenomenology reported earlier for opioid receptor-mediated stimulation of GTPase, i.e., 1) existence of ligands with both "positive" and "negative" intrinsic activity (the latter termed negative antagonists), 2) equipotency of neutral antagonists for the competitive blockade of the responses elicited both by agonists and by negative antagonists, and 3) apparent heterogeneity of binding sites for the binding isotherms of negative antagonists. The ternary complex model can also explain the differential effects of sodium on ligand binding and ligand-dependent GTPase activity, if we assume that this ion reduces the stability constant between receptor and G protein in membranes. Computer simulations predict that a negative antagonist exhibits a discrepancy between "biological" Ki (obtained by Schild plots) and true dissociation constant for the receptor, which increases as the fraction of "precoupled" receptors in the membrane increases. The demonstration of negative antagonism is definitive evidence for the existence of receptor coupling (hence activity) in the absence of ligand. Using this experimental paradigm, we show here that spontaneous receptor activity occurs in isolated membranes but not in intact NG108-15 cells.
Binding, Competitive↗
Selective interaction of beta 2- and alpha 2-adrenergic receptors with stimulatory and inhibitory guanine nucleotide-binding proteins.
In Chinese hamster ovary cells expressing recombinant beta 2-adrenergic receptors, isoproterenol enhanced cholera toxin-catalyzed ADP-ribosylation of the large form of G5 alpha. The effect was stereoselectively blocked by the enantiomers of propranolol, indicating receptor mediation. The ADP-ribosylated form of Gs alpha-subunit was resolved into a triplet in gradient gels. beta 2-Adrenergic receptors increased both the labelling and the apparent mass of the slower migrating forms of large Gs alpha, as determined by autoradiography and immunoblotting, suggesting that Gs alpha, can incorporate more than one ADP-ribose per molecule. In cells coexpressing similar amounts of beta 2-adrenergic, alpha 2-adrenergic, and m1 muscarinic receptors, beta 2 receptors stimulated the ADP-ribosylation of only large Gs and alpha 2 receptors that of only Gi; muscarinic receptors had no apparent effect. Thus, in native membranes there appears to be a selectivity for the interaction between adrenergic receptor subtypes and Gs alpha or Gi alpha subunits.
Adenosine Diphosphate Ribose↗
Allergic contact dermatitis due to budesonide.
Explore the source record for details and available documents.
Administration, Cutaneous↗
Selective autoregulation of endothelins in primary astrocyte cultures: endothelin receptor-mediated potentiation of endothelin-1 secretion.
Observations that primary rat astrocytes express high-affinity binding sites for endothelins and, in addition, are capable of producing not only endothelin-3 but also endothelin-1 prompted the investigation of a possible relation between endothelin peptides and receptors in these cells. Sarafotoxin S6b, an endothelin receptor agonist, was used as a tool to study endothelin receptor-mediated changes in the secretion of endothelin-1 and -3. The effects of sarafotoxin S6b and endothelin-1 in stimulating inositolphospholipid turnover as well as in inducing AP1 in primary astrocyte cultures were found to be similar. A low cross-reactivity of sarafotoxin S6b with endothelin-1 and -3 in the endothelin radioimmunoassays used here, along with a distinctly different elution position in high-performance liquid chromatography, allowed a clear discrimination between sarafotoxin and endothelins in the culture media. Stimulation of primary rat astrocytes with 10(-7) M sarafotoxin S6b for 1 hour resulted in a substantial increase in endothelin-1 immunoreactivity in the medium. This immunoreactivity reached a peak at 3 hours and showed no further increase after 8 and 24 hours. Treatment of our cultures with phorbol myristate acetate, lipopolysaccharide, tumor necrosis factor alpha, and norepinephrine for 24 hours led to only a moderate elevation of endothelin-1 immunoreactivity. Immunoreactive endothelin-3 was not affected by any of the treatments tested. Thus, our data suggest that endothelins in primary rat astrocytes are subject to selective autoregulation, as demonstrated by the potentiation of endothelin-1 secretion after activation of glial endothelin receptors.
Animals↗
Allergic contact dermatitis due to amcinonide.
Explore the source record for details and available documents.
Administration, Topical↗
[Study on ear burn model in mice and its significant application].
The experimental ear burn model in mice was developed in order to research the wound surface on a burn injury biochemically, and the following results were obtained: 1) The ear weight tended to increase up to 3 hr after preparation of the burn and then decreased subsequently. 2) Significant increase in leakage of Evans blue (EB) dye into the ear was observed in the burn group as compared to the non-burnt group. The amount of EB dye leaked per ear became the maximum in 3 hr which was similar to the increase in ear weight. 3) Correlation between the ear weight after burn and the amount of EB dye leaked into the ear on the burned site was observed up to 6 hr after preparation of the burn. 4) Vasopermeability of the ear was depressed with antihistamine treatment, but non-steroidal anti-inflammatory drugs had no effect. The ear weight of glucocorticoid-treated mice tended to be decreased as compared with the weight of the burned ear. 5) The histamine contents in the burned ear did not change, but the bradykinin contents significantly increased after the burn.
Animals↗