Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The nonestrogen receptor-mediated antiproliferative action of antiestrogen binding site (AEBS) ligands, including triphenylethylene antiestrogens and phenothiazines, has been linked to their ability to inhibit protein kinase C (PKC). Recent studies indicate that some diphenylmethane derivatives inhibit growth, are potent AEBS ligands, and antagonize histamine binding at an AEBS-related histamine site different from H1 and H2. Three novel diphenylmethane derivatives, N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine.HCI (DPPE), 4-decanoyl-DPPE (dec-DPPE), and 4-benzylphenyl decanoate (BPD) were studied in an attempt to determine whether PKC or histamine interactions best correlate with their antiproliferative effects. Platelet aggregation and the phosphorylation of a platelet Mr 47,000 protein (p47) induced by phorbol-12-myristate-13-acetate (PMA) represent two processes mediated by PKC. DPPE inhibits PMA-induced aggregation [50% inhibitory concentration (IC50) = 31.2 +/- 2.4 (SEM) x 10(-6) M] but does not significantly inhibit either PMA-induced phosphorylation of Mr 47,000 protein (IC50 greater than 500 x 10(-6) M), or binding of [3H]phorbol dibutyrate to platelets. dec-DPPE is a more potent inhibitor of PMA-induced platelet aggregation (IC50 = 18.8 +/- 0.7 x 10(-6) M), a weak inhibitor of Mr 47,000 phosphorylation (IC50 = 80-200 x 10(-6) M), but is without effect on [3H]phorbol dibutyrate binding. BPD, which lacks the alkylaminoethoxy side chain necessary for binding to the AEBS/DPPE site, is devoid of anti-PMA effects. These results are compared to the inhibition of [3H]histamine binding in rat cortex membranes (Ki value for DPPE = 0.83 +/- 0.62 x 10(-6) M; Ki value for dec-DPPE = 6.6 +/- 3.5 x 10(-6) M; BPD is inactive) and growth inhibition of MCF-7 cells (IC50 value for DPPE = 4.5 x 10(-6) M; IC50 value for dec-DPPE = 1.5 x 10(-5) M; BPD is ineffective at all concentrations tested). Thus, while dec-DPPE is a more potent inhibitor of PKC-mediated phosphorylation, DPPE is a more potent inhibitor of histamine binding and is correspondingly more antiproliferative than dec-DPPE. The results support a relationship between antagonism of histamine binding and growth inhibition but argue against an association between the antiproliferative effects of DPPE and dec-DPPE and inhibition of PKC. The findings for DPPE suggest that platelet response to PMA, antagonized by diphenylmethane-type AEBS-ligands, may be mediated, at least in part, by mechanisms other than activation of protein kinase C-dependent phosphorylation.
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PMID:Correlation of the antiproliferative action of diphenylmethane-derivative antiestrogen binding site ligands with antagonism of histamine binding but not of protein kinase C-mediated phosphorylation. 316 53

Multiple potentially injurious agents are present in smoke but the importance of each of these agents in producing lung injury as well as the mechanisms by which the lung injury is produced are unknown. In order to study smoke inhalation injury, we developed a synthetic smoke composed of a carrier of hot carbon particles of known size to which a single known common toxic agent in smoke, in this case HCI, could be added. We then exposed rats to the smoke, assayed their blood for the metabolites of thromboxane and prostacyclin, and intervened shortly after smoke with the cyclooxygenase inhibitors indomethacin or ibuprofen to see if the resulting lung injury could be prevented. Smoke exposure produced mild pulmonary edema after 6 h with a wet-to-dry weight ratio of 5.6 +/- 0.2 SEM (n = 11) compared with the non-smoke-exposed control animals with a wet-to-dry weight ratio of 4.3 +/- 0.2 (n = 12), p less than 0.001. Thromboxane B, and 6-keto-prostaglandin F1 alpha rose to 1,660 +/- 250 pg/ml (p less than 0.01) and to 600 +/- 100 pg/ml (p greater than 0.1), respectively, in the smoke-injured animals compared with 770 +/- 150 pg/ml and 400 +/- 100 pg/ml in the non-smoke-exposed control animals. Indomethacin (n = 11) blocked the increase in both thromboxane and prostacyclin metabolites but failed to prevent lung edema.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ibuprofen prevents synthetic smoke-induced pulmonary edema. 353 56

It has been reported that the presence of a smear layer on dentinal substrates can compromise bonding. Typically, smear layers are removed by acidic agents that selectively extract calcium salts from dentin surfaces to leave a collagen-rich substrate. Acid-conditioned dentin (i.e., demineralized) is then primed and an adhesive agent applied. In the present study, we removed smear layers by "polishing" dentin specimens with a hydroxyapatite paste and ultrasonication. Bonding procedures were carried out by means of an aqueous solution of 20% 2-methacryloyloxyethyl phenyl phosphoric acid (phenyl-P) and 30% 2-hydroxyethyl methacrylate, referred to as 2OP-30H, a "self-etching primer". The 20P-30H solution was applied to "intact" dentin (i.e., non-demineralized) for either 30 or 60 s. Control samples received no application (O s) of the self-etching primer. Mean tensile bond strengths (10 MPa) were similar in both the 30-second- and 60-second-primed groups. The widths of formed hybrid layers varied from 0.3 +/- 0.2 micron at O s application (control) to 2.1 +/- 0.3 micron for the 30-second group and 4.1 +/- 0.2 micron for the 60-second group. SEM and TEM observations revealed that the 20P-30H self-etching primer created diffusion channels into "intact" calcium-rich dentin which permitted monomer to infiltrate dentin substrates. Hybrid layers identified under microscopic examination demonstrated resistance to both HCI and NaOCI treatments, suggesting that the hybrid layer was not defective, and that bonding was stable.
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PMID:Bonding to intact dentin. 895 25

In an attempt to determine if there is any overlap in local and general anaesthetic binding sites, we have examined the effects of thiopental, phenobarbital, pentobarbital, propofol, ketamine (racemic and R(+)/S(-)), alfaxalone, etomidate and halothane on [3H]tetracaine binding to rat cerebrocortical membranes. Membranes were prepared in Tris HCI 50 mmol litre-1, pH 7.4, by homogenization and centrifugation. Binding assays were performed in 1-ml volumes of Tris HCI buffer at room temperature or 37 degrees C for halothane. Binding of [3H]tetracaine was displaced dose-dependently by unlabelled tetracaine with a mean pIC50 value of 6.91 (SEM 0.07) (123 nmol litre-1). With the exception of propofol (at high concentrations), all i.v. anaesthetic agents failed to displace the binding of [3H]tetracaine. In contrast, halothane produced a dose-dependent and statistically significant reduction in total [3H]tetracaine binding at clinically achievable concentrations (0.289, 0.885 and 1.484 mmol litre-1 equivalent to 1.0, 3.1 and 5.1 rat MAC) without markedly affecting the pIC50. Collectively these data may suggest some overlap in the binding sites for [3H]tetracaine and volatile but not i.v. general anaesthetic agents.
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PMID:Effects of i.v. anaesthetic agents and halothane on [3H]tetracaine binding to rat cerebrocortical membranes. 950 82

The present study demonstrates the in vitro and in vivo adsorption of peroxidase onto titanium surfaces. Titanium foils (mean +/- SEM: 365 +/- 2 mm(2), n = 114) were incubated during 30 min with lactoperoxidase (4 mg in 5 mL 100 mM phosphate buffer pH 7). After 15 washings by H(2)O, titanium foils were incubated with o-phenylenediamine (6 mg/mL) and H(2)O(2) (7 mM) during 30 min. The reaction was then stopped by the addition of HCI 1M and the absorbance of the liquid phase was read on a spectrophotometer at 492 nm. In vitro adsorbed lactoperoxidase onto titanium surfaces was 0.70 +/- 0.05 ng/mm(2) (mean +/- SEM, n = 30). X-ray photoelectron spectroscopy confirmed the incorporation of protein nitrogen onto titanium surfaces: the nitrogen atomic percentage increased from 0.9 +/- 0.3 to 12.7 +/- 0.2% (n = 3) and from 3.7 +/- 0.1 to 14.4 +/- 0. 4% (n = 5) when titanium foils were incubated in the lactoperoxidase solution during 30 min and 24 h respectively. In vivo, oral peroxidases adsorbed on titanium healing abutments from 0.01 to 0.58 ng/mm(2) (n = 19) after 2 weeks in the oral environment.
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PMID:Adsorption of peroxidase on titanium surfaces: A pilot study. 1100 26

Monochlorobenzene (MCB), dichlorobenzenes (DCBs), and 1,2,4-trichlorobenzene (124TCB) dechlorination experiments in water were carried out with freshly synthesized Pd/Fe particles. The pre- and postreacted Pd/Fe samples were characterized by applying various analytical techniques (XRD, SEM, TEM, and XPS). Chlorinated benzenes could be completely reduced by the Pd/Fe to benzene and the reaction followed the pseudo-first-order kinetics. The reaction rates followed the order TCB < DCBs < MCB, while among the DCBs the order was 1,4-dichlorobenzene >1,3-dichlorobenzene > or = 1,2-dichlorobenzene. Insignificant reactions were observed with the unpalladized iron, suggesting that Pd was the only reactive site in the Pd/Fe particles. The aged Pd/Fe particles exhibited significant decrease in its dechlorination reactivity. The loss of Pd/Fe reactivity could be due to Pd dislodgment from the aged Pd/Fe particles and Pd islets encapsulation by the iron oxides film developed over aging period. Reactivity of the aged Pd/Fe could be only partially restored after HCI treatment, while regeneration with the NaBH4 reduction method could not restore its activity, although zerovalent state of the iron was reinstated.
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PMID:Catalytic reduction of chlorobenzenes with Pd/Fe nanoparticles: reactive sites, catalyst stability, particle aging, and regeneration. 1804 36

A comparison of different purification procedures for single walled carbon nanotubes (SWCNTs) synthesized by laser-vapourization has been presented. The methods involved gas-phase oxidation by calcination, liquid-phase oxidation by H2O2, hydrothermal treatment and acid refluxing in HCI. Sample purity is documented with Raman spectroscopy, Transmission electron microscopy, Scanning electron microscopy and thermogravimetric analysis. Multi-spot analyses were done to check the homogeneity of the purified samples. Different purification processes produced SWCNT material with purity in the range of 48-78%. Raman and TEM results suggested that prolonged calcination results in selective etching of larger diameter nanotubes. SEM and TGA analyses showed increase in density of SWCNTs with better oxidation resistance after purification.
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PMID:Purification of laser synthesized SWCNTs by different methods: a comparative study. 1919 41

A ninety-day toxicity study of semicarbazide hydrochloride (SEM-HCl) was conducted in male and female Wistar Hannover GALAS rats fed diet containing the compound at concentration of 0, 250, 500 and 1000 ppm. Suppression of body weight gain and food consumption was found in both sexes at 1000 ppm throughout the study. Enlargement and deformation of knee joints were obvious at 500 and 1000 ppm from week 3, together with deformation of the thorax and tail. Histopathologically, disarrangement of chondrocytes and fissures in the cartilage matrix were apparent at all doses tested in epiphyseal and articular cartilage. The severity of these lesions increased dose-dependently, accompanied by increased connective tissues and bone deformation at high doses. Additionally, compact bones at 1000 ppm became thin, suggesting loss of bone mass. In the thoracic aorta, the edges of elastic laminae became rough and the interlaminar spaces were altered from a fibrillar to a rod or globular appearance. No abnormalities were detected in any other organs. Taken together, toxicological effects of subchronic exposure to SEM-HCI were mainly observed in bone, cartilage and the aorta, with the no-observed-adverse-effect-level estimated from the present histopathological examination of less than 250 ppm in both sexes.
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PMID:A ninety-day toxicity study of semicarbazide hydrochloride in Wistar Hannover GALAS rats. 1961 55

Polyaniline (PANI) is an important conductive polymer with good stability in the air and high conductivity. It can be used in the field of sensors, cells and capacitors. In this paper, PANI is prepared in the (NH4)2S2O8/HCI solution system. We used XRD, SEM and other relevant means to characterize the morphology and property of PANI-CSA, and we applied four-point probe measurement and FTIR to study the optical and electrical properties. We also analyzed the possible impact to infrared reflectance of various doping concentrations and the mechanism. The results show that the PANI-CSA film has the best performance and the highest infrared reflectivity when the doping ratio is 2:2.
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PMID:Synthesis and properties of nano-polyaniline films doped with camphor sulfonic acid. 2473 62

We performed a combined study to determine the chronic toxicity and carcinogenicity of semicarbazide hydrochloride (SEM-HCl). Male and female Wistar Hannover GALAS rats were fed a diet containing SEM-HCl at 0, 10, 50, and 250ppm for 52weeks (10 rats/sex/group) or for 104weeks (50 rats/sex/group). Enlargement of the knee joints was apparent in both sexes at 250ppm. Reduced body weight was observed at 250ppm from week 76 only in males. SEM-HCl exerted no toxic effects on hematology, serum biochemistry, or organ weights. Histopathologically, disarrangement of chondrocytes accompanied by increased connective tissues, and degeneration of articular cartilage were found in males at 50ppm and above and in females at 250ppm. Mild changes in the elastic laminae were observed at 250ppm for both sexes in the chronic toxicity study. There were no significant intergroup differences in the incidences or types of any tumors. Taken together, toxicological effects of chronic exposure to SEM-HCI mainly occurred in the bone, cartilage, and aorta. Based on histopathological findings, the no-observed-adverse-effect-level was 10ppm in males and 50ppm in females (equal to 0.6mg/kg/day in males and 3.9mg/kg/day in females). SEM-HCl was not carcinogenic in rats.
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PMID:Chronic toxicity and carcinogenicity of semicarbazide hydrochloride in Wistar Hannover GALAS rats. 2513 20


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