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1.
PLoS One ; 17(12): e0266435, 2022.
Article in English | MEDLINE | ID: mdl-36516131

ABSTRACT

We apply a heterogeneous graph convolution network (GCN) combined with a multi-layer perceptron (MLP) denoted by GCNMLP to explore the potential side effects of drugs. Here the SIDER, OFFSIDERS, and FAERS are used as the datasets. We integrate the drug information with similar characteristics from the datasets of known drugs and side effect networks. The heterogeneous graph networks explore the potential side effects of drugs by inferring the relationship between similar drugs and related side effects. This novel in silico method will shorten the time spent in uncovering the unseen side effects within routine drug prescriptions while highlighting the relevance of exploring drug mechanisms from well-documented drugs. In our experiments, we inquire about the drugs Vancomycin, Amlodipine, Cisplatin, and Glimepiride from a trained model, where the parameters are acquired from the dataset SIDER after training. Our results show that the performance of the GCNMLP on these three datasets is superior to the non-negative matrix factorization method (NMF) and some well-known machine learning methods with respect to various evaluation scales. Moreover, new side effects of drugs can be obtained using the GCNMLP.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Neural Networks, Computer , Humans , Algorithms , Machine Learning
2.
Sci Rep ; 11(1): 22801, 2021 Nov 23.
Article in English | MEDLINE | ID: mdl-34815442

ABSTRACT

We study the existence of nontrivial solution branches of three-coupled Gross-Pitaevskii equations (CGPEs), which are used as the mathematical model for rotating spin-1 Bose-Einstein condensates (BEC). The Lyapunov-Schmidt reduction is exploited to test the branching of nontrivial solution curves from the trivial one in some neighborhoods of bifurcation points. A multilevel continuation method is proposed for computing the ground state solution of rotating spin-1 BEC. By properly choosing the constraint conditions associated with the components of the parameter variable, the proposed algorithm can effectively compute the ground states of spin-1 [Formula: see text] and [Formula: see text] under rapid rotation. Extensive numerical results demonstrate the efficiency of the proposed algorithm. In particular, the affect of the magnetization on the CGPEs is investigated.

3.
Horm Metab Res ; 41(7): 542-7, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19373748

ABSTRACT

Glucosamine has been widely used to treat osteoporosis in clinic and it shows an effect on hexosamine biosynthetic pathway in glucose-induced insulin resistance. However, glucosamine and chronic hyperglycemia is not correlative. Thus, we used C (2)C (12) cell line to carry out the uptake assay of 2-[14C]-deoxy-d-glucose and [3H]-glucosamine. Glucosamine inhibited the in vitro glucose uptake in a concentration-dependent manner. The glucose transporter GLUT4 prepared for [3H]-glucosamine uptake showed a concentration-dependent competition between glucose and glucosamine uptake. The effects of glucosamine on glucose tolerance and homeostasis model assessment (HOMA) were also determined in normal Wistar and fructose-fed rats. Both plasma glucose levels and/or HOMA index were not changed in normal rats treated with glucosamine as compared with the saline-treated control. However, we found that glucosamine exhibited an effect on the expression of farnesoid X receptor in liver to exacerbate the values of HOMA and accelerate the development of insulin resistance in fructose-fed rats. Thus, glucosamine should be applied with caution in type-2 diabetic patients.


Subject(s)
Fructose/metabolism , Glucosamine/metabolism , Insulin Resistance , Animals , Cell Line , Gene Expression , Glucose/metabolism , Glucose Transporter Type 4/genetics , Glucose Transporter Type 4/metabolism , Male , Mice , Rats , Rats, Wistar , Receptors, Cytoplasmic and Nuclear/genetics , Receptors, Cytoplasmic and Nuclear/metabolism
4.
Cell Signal ; 13(9): 633-43, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11495721

ABSTRACT

Inhalation of tumour necrosis factor-alpha (TNF-alpha) induced a bronchial hyperreactivity to contractile agonists. However, the mechanisms of TNF-alpha involved in the pathogenesis of bronchial hyperreactivity were not completely understood. Therefore, we investigated the effect of TNF-alpha on bradykinin (BK)-induced inositol phosphate (IP) accumulation and Ca(2+) mobilization, and up-regulation of BK receptor density in canine cultured tracheal smooth muscle cells (TSMCs). Pretreatment of TSMCs with TNF-alpha potentiated BK-induced IP accumulation and Ca(2+) mobilization. However, there was no effect on the IP response induced by endothelin-1 (ET-1), 5-hydroxytryptamine (5-HT), and carbachol. Pretreatment with PDGF B-chain homodimer (PDGF-BB) also enhanced BK-induced IP response. These enhancements induced by TNF-alpha and PDGF-BB might be due to an increase in BK B(2) receptor density (B(max)), since [3H]BK binding to TSMCs was inhibited by the B(2) selective agonist and antagonist, BK and Hoe 140, but not by the B(1) selective reagents. The enhancing effects of TNF-alpha and PDGF-BB were attenuated by PD98059 (an inhibitor of activation of MAPK kinase, MEK) and cycloheximide (an inhibitor of protein synthesis), suggesting that TNF-alpha may share a common signalling pathway with PDGF-BB via protein(s) synthesis in TSMCs. Furthermore, overexpression of dominant negative mutants, H-Ras-15A and Raf-N4, significantly suppressed p42/p44 mitogen-activated protein kinase (MAPK) activation induced by TNF-alpha and PDGF-BB and attenuated the effect of TNF-alpha on BK-induced IP response, indicating that Ras and Raf may be required for activation of these kinases. These results suggest that the augmentation of BK-induced responses produced by TNF-alpha might be, at least in part, mediated through activation of Ras/Raf/MEK/MAPK pathway in TSMCs.


Subject(s)
Bradykinin/pharmacology , MAP Kinase Signaling System , Muscle, Smooth/metabolism , Trachea/cytology , Tumor Necrosis Factor-alpha/pharmacology , Animals , Bradykinin/metabolism , Calcium/metabolism , Cells, Cultured , Dogs , Drug Synergism , Enzyme Activation , Enzyme Inhibitors/pharmacology , Flavonoids/pharmacology , Inositol Phosphates/metabolism , MAP Kinase Kinase 1 , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/metabolism , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-raf/metabolism , Proto-Oncogene Proteins c-raf/physiology , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/physiology
5.
Cell Signal ; 13(4): 257-67, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11306243

ABSTRACT

The elevated level of thrombin has been detected in the airway fluids of asthmatic patients. However, the implication of thrombin in the pathogenesis of bronchial hyperreactivity was not completely understood. Therefore, in this study we investigated the effect of thrombin on cell proliferation and p42/p44 mitogen-activated protein kinase (MAPK) activation in human tracheal smooth muscle cells (TSMCs). Thrombin stimulated [3H]thymidine incorporation and p42/p44 MAPK phosphorylation in a time- and concentration-dependent manner in TSMCs. Pretreatment of TSMCs with pertussis toxin (PTX) significantly inhibited [3H]thymidine incorporation and phosphorylation of MAPK induced by thrombin. These responses were attenuated by tyrosine kinase inhibitors genistein and herbimycin A, phosphatidyl inositide (PI)-phospholipase C (PLC) inhibitor U73122, protein kinase C (PKC) inhibitor GF109203X, removal of Ca(2+) by addition of BAPTA/AM plus EGTA, and PI 3-kinase inhibitors wortmannin and LY294002. In addition, thrombin-induced [3H]-thymidine incorporation and p42/p44 MAPK phosphorylation was completely inhibited by PD98059 (an inhibitor of MEK1/2), indicating that activation of MEK1/2 was required for these responses. Furthermore, overexpression of dominant negative mutants, RasN17 and Raf-301, significantly suppressed p42/p44 MAPK activation induced by thrombin and PDGF-BB, indicating that Ras and Raf may be required for activation of these kinases. These results conclude that the mitogenic effect of thrombin was mediated through the activation of Ras/Raf/MEK/MAPK pathway. Thrombin-mediated MAPK activation was modulated by PI-PLC, Ca(2+), PKC, tyrosine kinase, and PI 3-kinase associated with cell proliferation in cultured human TSMCs.


Subject(s)
MAP Kinase Signaling System , Muscle, Smooth/cytology , Muscle, Smooth/enzymology , Trachea/cytology , Androstadienes/pharmacology , Benzoquinones , Blotting, Western , Cell Division , Cells, Cultured , Chelating Agents/pharmacology , Chromones/pharmacology , Dose-Response Relationship, Drug , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Enzyme Activation , Enzyme Inhibitors/pharmacology , Estrenes/pharmacology , Flavonoids/pharmacology , Genistein/pharmacology , Humans , Indoles/pharmacology , Lactams, Macrocyclic , Maleimides/pharmacology , Mitogen-Activated Protein Kinase 1/chemistry , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinases/chemistry , Mitogen-Activated Protein Kinases/metabolism , Morpholines/pharmacology , Pertussis Toxin , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation , Plasmids/metabolism , Protein Isoforms , Protein Kinase C/metabolism , Proto-Oncogene Proteins c-raf/metabolism , Pyrrolidinones/pharmacology , Quinones/pharmacology , Rifabutin/analogs & derivatives , Thrombin/metabolism , Thrombin/pharmacology , Time Factors , Transfection , Virulence Factors, Bordetella/pharmacology , Wortmannin , ras Proteins/metabolism
6.
Br J Pharmacol ; 132(7): 1531-41, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11264247

ABSTRACT

1. It has been demonstrated that oxidized low-density lipoprotein (OX-LDL) is a risk factor in atherosclerosis by stimulating vascular smooth muscle cell (VSMC) proliferation. However, the mechanisms of OX-LDL-induced cell proliferation are not completely understood. Therefore, we investigated the effect of OX-LDL on cell proliferation associated with mitogen-activated protein kinase (MAPK) activation in rat cultured VSMCs. 2. Both native-LDL (N-LDL) and OX-LDL induced a time- and concentration-dependent incorporation of [(3)H]-thymidine in VSMCs. 3. OX-LDL induced time- and concentration-dependent phosphorylation of p42/p44 MAPK. Pretreatment of these cells with pertussis toxin or U73122 attenuated the OX-LDL-induced responses. 4. Pretreatment with PMA for 24 h, preincubation with a PKC inhibitor staurosporine or the tyrosine kinase inhibitors, genistein and herbimycin A for 1 h, substantially reduced [(3)H]-thymidine incorporation and p42/p44 MAPK phosphorylation induced by OX-LDL. 5. Removal of Ca(2+) by BAPTA/AM or depletion of the internal Ca(2+) pool by thapsigargin significantly inhibited OX-LDL-induced [(3)H]-thymidine incorporation and p42/p44 MAPK phosphorylation. 6. OX-LDL-induced [(3)H]-thymidine incorporation and p42/p44 MAPK phosphorylation was inhibited by PD98059 (an inhibitor of MEK1/2) and SB203580 (an inhibitor of p38 MAPK) in a concentration-dependent manner. 7. Overexpression of dominant negative mutants of Ras (H-Ras-15A) and Raf (Raf-N4) significantly suppressed MEK1/2 and p42/p44 MAPK activation induced by OX-LDL and PDGF-BB, indicating that Ras and Raf may be required for activation of these kinases. 8. These results suggest that the mitogenic effect of OX-LDL is mediated through a PTX-sensitive G protein-coupled receptor that involves the activation of the Ras/Raf/MEK/MAPK pathway similar to that of PDGF-BB in rat cultured VSMCs.


Subject(s)
Lipoproteins, LDL/pharmacology , Mitogen-Activated Protein Kinases/drug effects , Mitogens/pharmacology , Muscle, Smooth, Vascular/drug effects , Animals , Benzoquinones , Calcium/pharmacology , DNA/biosynthesis , DNA/drug effects , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Estrenes/pharmacology , Flavonoids/pharmacology , Genistein/pharmacology , Humans , Lactams, Macrocyclic , MAP Kinase Signaling System/drug effects , Mitogen-Activated Protein Kinase 1/drug effects , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/metabolism , Pertussis Toxin , Phosphorylation/drug effects , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/metabolism , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins c-raf/metabolism , Pyrrolidinones/pharmacology , Quinones/pharmacology , Rats , Rats, Sprague-Dawley , Rifabutin/analogs & derivatives , Staurosporine/pharmacology , Virulence Factors, Bordetella/pharmacology , ras Proteins/metabolism
7.
Biochem J ; 354(Pt 2): 439-46, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11171124

ABSTRACT

Elevated levels of several cytokines including interleukin-1beta (IL-1beta) have been detected in airway fluid of asthmatic patients. Inhalation of IL-1beta induced a bronchial hyper-reactivity to contractile agonists. However, the implication of IL-1beta in the pathogenesis of bronchial hyper-reactivity is not completely understood. Therefore, we investigated the effect of IL-1beta on bradykinin (BK)-induced inositol phosphate [Ins(X)P] accumulation and Ca2+ mobilization, and up-regulation of BK receptor density in canine cultured tracheal smooth-muscle cells (TSMCs). Treatment of TSMCs with IL-1beta potentiated BK-induced Ins(X)P accumulation and Ca2+ mobilization. However, there was no effect on the Ins(X)P response induced by endothelin-1, 5-hydroxytryptamine or carbachol. Treatment with platelet-derived growth factor B-chain homodimer (PDGF-BB) also enhanced the BK-induced Ins(X)P response. These enhancements by IL-1beta and PDGF-BB might be due to an up-regulation of BK B(2) receptor density (B(max)), since [(3)H]BK binding to TSMCs was inhibited by the B(2)-selective agonist and antagonist, BK and Hoe 140, but not by B(1)-selective reagents. The enhancing effects of IL-1beta and PDGF-BB on Ins(X)P accumulation, Ca2+ mobilization and B(max) were attenuated by PD98059 [an inhibitor of activation of mitogen-activated protein kinase (MAPK) kinase, MEK] and cycloheximide (an inhibitor of protein synthesis), suggesting that IL-1beta may share a common signalling pathway with PDGF-BB via protein synthesis. Furthermore, overexpression of dominant negative mutants, H-Ras-15A and Raf-N4, significantly suppressed the up-regulation of BK receptors induced by IL-1beta, indicating that Ras and Raf may be required for activation of these kinases. These results suggest that the augmentation of BK-induced responses produced by IL-1beta might be, at least in part, mediated through activation of the Ras/Raf/MEK/MAPK pathway in TSMCs.


Subject(s)
Bradykinin/pharmacology , Calcium/metabolism , Interleukin-1/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth/metabolism , Phosphatidylinositols/metabolism , Animals , Cell Division/drug effects , Cells, Cultured , Dogs , Female , Hydrolysis , Male , Muscle, Smooth/cytology , Muscle, Smooth/drug effects , Proto-Oncogene Proteins c-raf/metabolism , Receptors, Bradykinin/metabolism , Trachea/cytology , Trachea/drug effects , Trachea/metabolism , Up-Regulation , ras Proteins/metabolism
8.
Br J Pharmacol ; 130(8): 1799-808, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10952668

ABSTRACT

Bacterial lipopolysaccharide (LPS) was found to induce inflammatory responses and to enhance bronchial hyperreactivity to several contractile agonists. However, the implication of LPS in the pathogenesis of bronchial hyperreactivity was not completely understood. Therefore, in this study, we investigated the effect of LPS on mitogen-activated protein kinase (MAPK) activation associated with potentiation of bradykinin (BK)-induced inositol phosphates (IPs) accumulation and Ca(2+) mobilization in canine cultured tracheal smooth muscle cells (TSMCs). LPS stimulated phosphorylation of p42/p44 MAPK in a time- and concentration-dependent manner using a Western blot analysis against a specific phosphorylated form of MAPK antibody. Maximal stimulation of the p42 and p44 MAPK isoforms occurred after 7 min-incubation and the maximal effect was achieved with 100 microg ml(-1) LPS. Pretreatment of TSMCs with LPS potentiated BK-induced IPs accumulation and Ca(2+) mobilization. However, there was no effect on the IPs response induced by endothelin-1, 5-hydroxytryptamine, and carbachol. In addition, pretreatment with PDGF-BB enhanced BK-induced IPs response. These enhancements by LPS and PDGF-BB might be due to an increase in BK B(2) receptor density (B(max)) in TSMCs, characterized by competitive inhibition of [(3)H]-BK binding using B(1) and B(2) receptor-selective reagents. The enhancing effects of LPS and PDGF-BB were attenuated by PD98059, an inhibitor of MAPK kinase (MEK), suggesting that the effect of LPS may share a common signalling pathway with PDGF-BB in TSMCs. Furthermore, overexpression of dominant negative mutants, H-Ras-15A and Raf-N4, significantly suppressed p42/p44 MAPK activation induced by LPS and PDGF-BB, indicating that Ras and Raf may be required for activation of these kinases. These results suggest that the augmentation of BK-induced responses produced by LPS might be, at least in part, mediated through activation of Ras/Raf/MEK/MAPK pathway in TSMCs.


Subject(s)
Bradykinin/pharmacology , Lipopolysaccharides/pharmacology , Muscle, Smooth/drug effects , Protein Serine-Threonine Kinases/metabolism , Trachea/drug effects , ras Proteins/drug effects , Animals , Binding, Competitive/drug effects , Bradykinin/metabolism , Calcium/metabolism , Cells, Cultured , Dogs , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Female , Flavonoids/pharmacology , Imidazoles/pharmacology , Inositol Phosphates/metabolism , Isoenzymes/drug effects , Isoenzymes/metabolism , Male , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth/cytology , Muscle, Smooth/physiology , Phosphorylation/drug effects , Proto-Oncogene Proteins c-raf/metabolism , Pyridines/pharmacology , Signal Transduction/drug effects , Time Factors , Trachea/metabolism , Trachea/physiology , Tritium , ras Proteins/metabolism
9.
Br J Pharmacol ; 130(4): 891-9, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10864897

ABSTRACT

The elevated levels of inflammatory cytokines such as tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) have been found in the fluid of airways in symptomatic asthmatics. These cytokines have been considered as mitogens to stimulate cell proliferation in tracheal smooth muscle cells (TSMCs). We therefore investigated the effects of TNF-alpha and IL-1beta on cell proliferation and activation of p42/p44 mitogen-activated protein kinase (MAPK) in these cells. TNF-alpha and IL-1beta induced [(3)H]-thymidine incorporation in a time- and concentration-dependent manner. The maximal stimulation of [(3)H]-thymidine incorporation induced by TNF-alpha and IL-1beta was seen 12 h after incubation with these cytokines. In response to TNF-alpha and IL-1beta, p42/p44 MAPK was activated with a concentration-dependent manner in TSMCs. Pretreatment of TSMCs with pertussis toxin did not change DNA synthesis and phosphorylation of MAPK induced by TNF-alpha and IL-1beta. These responses were attenuated by a tyrosine kinase inhibitor herbimycin, a phosphatidyl choline (PC)-phospholipase C (PLC) inhibitor D609, a phosphatidyl inositide (PI)-PLC inhibitor U73122, a protein kinase C inhibitor staurosporine, and removal of Ca(2+) by addition of BAPTA/AM plus EGTA. TNF-alpha- and IL-1beta-induced [(3)H]-thymidine incorporation and phosphorylation of p42/p44 MAPK was completely inhibited by PD98059 (an inhibitor of MEK1/2), indicating that activation of MEK1/2 was required for these responses. These results suggest that the mitogenic effects of TNF-alpha and IL-1beta were mediated through the activation of MEK1/2 and p42/p44 MAPK pathway. TNF-alpha- and IL-1beta-mediated responses were modulated by PLC, Ca(2+), PKC, and tyrosine kinase associated with cell proliferation in TSMCs.


Subject(s)
Cell Division/drug effects , Interleukin-1/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth/drug effects , Tumor Necrosis Factor-alpha/pharmacology , Animals , Benzoquinones , Bridged-Ring Compounds/pharmacology , Calcium/metabolism , Chelating Agents/pharmacology , DNA/biosynthesis , DNA/drug effects , Dogs , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Enzyme Activation/drug effects , Estrenes/pharmacology , Female , Flavonoids/pharmacology , Isoenzymes/metabolism , Lactams, Macrocyclic , Male , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Muscle, Smooth/cytology , Muscle, Smooth/metabolism , Norbornanes , Pertussis Toxin , Phosphorylation/drug effects , Protein Kinase C/metabolism , Pyrrolidinones/pharmacology , Quinones/pharmacology , Rifabutin/analogs & derivatives , Thiocarbamates , Thiones/pharmacology , Thymidine/metabolism , Trachea/cytology , Tritium , Type C Phospholipases/antagonists & inhibitors , Virulence Factors, Bordetella/pharmacology
10.
Br J Pharmacol ; 129(7): 1481-9, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10742305

ABSTRACT

1. Extracellular purine and pyrimidine nucleotides have been implicated in the regulation of several cellular functions including mitogenesis. In this study, experiments were conducted to characterize the P2Y receptor on C(6) glioma cells responsible for stimulating cell proliferation associated with mitogen-activated protein kinase (MAPK) activation. 2. UTP and ATP produced a similar effect on [(3)H]-thymidine incorporation in a time- and concentration-dependent manner, suggesting the involvement of P2Y(2) receptor in mediating proliferation of C(6) glioma cells. 3. In response to UTP, both p42 and p44 MAPK were activated in a time- and concentration-dependent manner using Western blot analysis with an anti-phospho-p42/p44 MAPK antibody. The phosphorylation reached maximal levels after 5 min and declining by 30 min. 4. Pretreatment with pertussis toxin (PTX) did not change these responses to UTP. Both DNA synthesis and phosphorylation of MAPK in response to UTP were attenuated by tyrosine kinase inhibitors, genistein and herbimycin A, protein kinase C (PKC) inhibitors, staurosporine and GF109203X, and removal of Ca(2+) by addition of BAPTA/AM plus EGTA. 5. UTP-induced [(3)H]-thymidine incorporation and p42/p44 MAPK phosphorylation was completely inhibited by PD98059 (an inhibitor of MEK1/2). Furthermore, we showed that overexpression of dominant negative mutants of Ras (RasN17) and Raf (Raf-301) completely suppressed MEK1/2 and p42/p44 MAPK activation induced by ATP and UTP. 6. These results conclude that the mitogenic effect of UTP mediated through a P2Y(2) receptor that involves the activation of Ras/Raf/MEK/MAPK pathway. UTP-mediated MAPK activation was modulated by Ca(2+), PKC, and tyrosine kinase associated with cell proliferation in cultured C(6) glioma cells.


Subject(s)
Cell Division/physiology , MAP Kinase Signaling System/physiology , Protein Serine-Threonine Kinases/metabolism , Receptors, Purinergic P2/physiology , ras Proteins/metabolism , Adenosine Triphosphate/pharmacology , Animals , Calcium/pharmacology , DNA/biosynthesis , DNA/drug effects , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Flavonoids/pharmacology , Glioma/pathology , Indoles/pharmacology , Isoenzymes/metabolism , Maleimides/pharmacology , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/metabolism , Pertussis Toxin , Phosphorylation/drug effects , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/metabolism , Protein Serine-Threonine Kinases/antagonists & inhibitors , Proto-Oncogene Proteins c-raf/antagonists & inhibitors , Proto-Oncogene Proteins c-raf/metabolism , Receptors, Purinergic P2Y2 , Staurosporine/pharmacology , Tumor Cells, Cultured , Uridine Triphosphate/pharmacology , Virulence Factors, Bordetella/pharmacology
11.
Cell Signal ; 12(4): 205-14, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10781927

ABSTRACT

Oxidized low-density lipoprotein (OX-LDL) contributes significantly to the development of atherosclerosis. However, the mechanisms of OX-LDL-induced vascular smooth muscle cell (VSMC) proliferation are not completely understood. Therefore, we investigated the effect of OX-LDL on cell proliferation associated with a specific pattern of mitogen-activated protein kinase (MAPK) by [3H]thymidine incorporation and p42/p44 MAPK phosphorylation in canine cultured VSMCs. OX-LDL-induced [3H]thymidine incorporation and p42/p44 MAPK phosphorylation in a time- and concentration-dependent manner in VSMCs. Pretreatment of these cells with pertussis toxin (PTX) for 24 hours attenuated the OX-LDL-induced [3H]thymidine incorporation and p42/p44 MAPK phosphorylation, indicating that these responses were mediated through a receptor coupled to a PTX-sensitive G protein. In cells pretreated with PMA for 24 h and with either the PKC inhibitor staurosporine or the tyrosine kinase inhibitor genistein for 1h, substantially reduced the [3H]thymidine incorporation and p42/p44 MAPK phosphorylation in response to OX-LDL. Removal of Ca(2+) by addition of BAPTA/AM plus EGTA significantly inhibited OX-LDL-induced [3H]thymidine incorporation and p42/p44 MAPK phosphorylation, indicating the requirement of Ca(2+) for these responses. OX-LDL-induced [3H]thymidine incorporation and p42/p44 MAPK phosphorylation was completely inhibited by PD98059 (an inhibitor of MEK1/2) and SB203580 (an inhibitor of p38 MAPK). Furthermore, we also showed that overexpression of dominant negative mutants of Ras (RasN17) and Raf (Raf-301) completely suppressed MEK1/2 and p42/p44 MAPK activation induced by OX-LDL and PDGF-BB, indicating that Ras and Raf may be required for activation of these kinases. Taken together, these results suggest that the mitogenic effect of OX-LDL is mediated through a PTX-sensitive G-protein-coupled receptor that involves the activation o Ras/Raf/MEK/MAPK pathway similar to those of PDGF-BB in canine cultured VSMCs.


Subject(s)
Lipoproteins, LDL/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth, Vascular/physiology , Animals , Aorta , Cell Division , Cells, Cultured , Dogs , Enzyme Activation , GTP-Binding Proteins/metabolism , Humans , Kinetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Muscle, Smooth, Vascular/cytology , Pertussis Toxin , Phosphorylation , Signal Transduction/drug effects , Signal Transduction/physiology , Transfection , Virulence Factors, Bordetella/pharmacology
12.
Anesthesiology ; 91(3): 750-9, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10485787

ABSTRACT

BACKGROUND: Propofol has been shown to produce relaxation of preconstricted airway smooth muscle. Although the inhibition of calcium mobilization is supposed to be the major mechanism of action, the whole picture of the mechanisms is not completely clear. METHODS: Contractile response was performed using canine tracheal rings. The effects of propofol on carbachol-induced mobilization of intracellular Ca2+ and phosphoinositide hydrolysis were measured using cultured canine tracheal smooth muscle cells by monitoring fura-2 signal and assessing the accumulation of [3H]-inositol phosphates. To detect the effect of propofol on muscarinic receptor density and affinity, [3H]N-methyl-scopolamine was used as a radioligand for receptor binding assay. RESULTS: Pretreatment with propofol shifts the concentration-response curves of carbachol-induced smooth muscle contraction to the right in a concentration-dependent manner without changing the maximal response. Propofol not only decreased the release of Ca2+ from internal stores but also inhibited the calcium influx induced by carbachol. In addition, carbachol-induced inositol phosphate accumulation was attenuated by propofol; the inhibitory pattern was similar to the contractile response. Moreover, propofol did not alter the density of muscarinic receptors. The dissociation constant value was not altered by pretreatment with 100 microM propofol but was significantly increased by 300 microM (propofol, 952+/-229 pM; control, 588+/-98 pM; P<0.05). CONCLUSIONS: Propofol attenuates the muscarinic receptor-mediated airway muscle contraction. The mechanism underlying these effects was attenuation of inositol phosphate generation and inhibition of Ca2+ mobilization through the inhibition of the receptor-coupled signal-transduction pathway.


Subject(s)
Anesthetics, Intravenous/pharmacology , Muscle Contraction/drug effects , Propofol/pharmacology , Trachea/drug effects , Animals , Calcium/metabolism , Carbachol/pharmacology , Dogs , Female , In Vitro Techniques , Inositol 1,4,5-Trisphosphate/biosynthesis , Male , N-Methylscopolamine/metabolism , Trachea/physiology
13.
Cell Signal ; 11(5): 361-70, 1999 May.
Article in English | MEDLINE | ID: mdl-10376810

ABSTRACT

The effect of 5-hydroxytryptamine (5-HT) on phospholipase C (PLC)-mediated phosphoinositide (PI) hydrolysis and intracellular Ca2+ ([Ca2+]i) changes was investigated in canine cultured aorta smooth muscle cells (ASMCs). 5-HT-stimulated inositol phosphate (IP) accumulation was time and concentration dependent with a half-maximal response (pEC50) and a maximal response at 6.4 and 10 microM, n = 6, respectively. Stimulation of ASMCs by 5-HT produced an initial transient peak followed by a sustained, concentration-dependent elevation in [Ca+]i. The half-maximal response (pEC50) values of 5-HT for the peak and sustained plateau were 7.1 and 6.9, respectively. Ketanserin and mianserin (1 and 3 nM), 5-HT2A antagonists, were equipotent and had high affinity in antagonising the 5-HT-induced IP accumulation and [Ca2+]i change with pK(B) values of 8.6-9.1 and 8.6-9.4, respectively. In contrast, the concentration-effect curves of 5-HT-induced IP and [Ca2+]i responses were not shifted until the concentrations of NAN-190 and metoctopramide (5-HT1A and 5-HT3 receptor antagonists, respectively) were increased to as high as 1 microM with pK(B) values of 5.7-6.3 and 6.1-6.6, respectively, indicating that the 5-HT receptor-mediated responses had low affinity for these antagonists. Pre-treatment of ASMCs with pertussis toxin (100 ng/mL, 24 h) caused a significant inhibition of 5-HT-induced IP accumulation and [Ca2+]i change in ASMCs. Depletion of external Ca2+ or removal of Ca2+ by addition of EGTA led to a significant attenuation of IP accumulation and [Ca2+]i change induced by 5-HT. Influx of external Ca2+ was required for the 5-HT-induced responses, because Ca2+-channel blockers--verapamil, nifedipine and Ni2+--partly inhibited the 5-HT-induced IP accumulation and Ca2+ mobilisation. The sustained elevation of [Ca2+]i response to 5-HT was dependent on the presence of external Ca2+. Removal of external Ca2+ by addition of 5 mM EGTA during the sustained phase caused a rapid decline in [Ca2+]i to lower than the resting level. The sustained elevation of [Ca2+]i could then be evoked by addition of 1.8 mM Ca2+ in the continued presence of 5-HT. These results demonstrate that 5-HT directly stimulates PLC-mediated PI hydrolysis and Ca2+ mobilisation, at least in part, through a pertussis toxin-sensitive G protein in canine ASMCs. 5-HT2A receptors may be predominantly mediating IP accumulation, and subsequently IP-induced Ca2+ mobilisation may function as the transducing mechanism for 5-HT-stimulated contraction of aorta smooth muscle.


Subject(s)
Calcium/metabolism , Muscle, Smooth, Vascular/metabolism , Phosphatidylinositols/metabolism , Serotonin/metabolism , Animals , Aorta/cytology , Cells, Cultured , Dogs , Female , Hydrolysis , Inositol Phosphates/metabolism , Male , Muscle, Smooth, Vascular/cytology , Pertussis Toxin , Serotonin/pharmacology , Serotonin Antagonists/pharmacology , Serotonin Receptor Agonists/pharmacology , Virulence Factors, Bordetella/pharmacology
15.
J Nucl Med ; 36(9): 1590-4, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7658215

ABSTRACT

UNLABELLED: Hepatic arterial embolization (HAE) is the treatment of choice for inoperable hepatocellular carcinoma. There are functional changes following HAE in the tumor and in the adjoining normal liver and biliary structures. We sought to determine if a 99mTc-HIDA hepatobiliary scan could evaluate the morphological and functional changes of the liver and biliary systems in patients with hepatocellular carcinoma undergoing HAE. METHODS: Patients with hepatoma were evaluated by 99mTc-HIDA hepatobiliary scans before and after HAE. RESULTS: Ten patients with histologically proven hepatomas had 44 99mTc-HIDA scans over a 319-mo period. Liver uptake was good in all patients, none developed hepatic failure. Liver tumors were detected in five of the eight studies done before the first HAE. The HIDA scan failed to locate the tumor throughout the whole study period in only one patient. Two patients showed evidence of tumor uptake of the HIDA agent. In one of these two patients the hot uptake disappeared after the HAE but reappeared after tumor recurrence. Gallbladder filling time and contractility worsened in all eight patients the day after embolization. On the HIDA scans, the gallbladder was not visualized in three of four patients who survived longer than 40 mo after HAE. Bile stasis in the left intrahepatic duct was found in six of the eight patients who survived longer than 8 mo after HAE. CONCLUSIONS: Biliary complications were common in patients who received HAE, and HIDA scans may be useful for evaluating the biliary system and hot uptake in hepatocellular carcinoma in candidates for HAE.


Subject(s)
Biliary Tract/diagnostic imaging , Carcinoma, Hepatocellular/diagnostic imaging , Embolization, Therapeutic , Liver Neoplasms/diagnostic imaging , Liver/diagnostic imaging , Adult , Aged , Carcinoma, Hepatocellular/therapy , Female , Humans , Imino Acids , Liver Neoplasms/therapy , Male , Middle Aged , Organotechnetium Compounds , Prospective Studies , Radionuclide Imaging , Technetium Tc 99m Lidofenin
16.
Changgeng Yi Xue Za Zhi ; 18(2): 190-3, 1995 Jun.
Article in Chinese | MEDLINE | ID: mdl-7641115

ABSTRACT

A 67-year-old man was hospitalized with the chief complaint of diffuse abdominal pain for 3 days. Hypercalcemia and acute pancreatitis was found by laboratory examination. Abdominal CT scans showed swelling of the pancreas, multiple liver tumors and osteolytic lesions of bone. Upper mediastinal lobulated mass was suspected from chest x-ray examination, then small cell lung cancer (SCLC) was proved by bronchoscopic and pathological examination. The final diagnosis is SCLC with liver and bone metastasis associated with hypercalcemia and acute pancreatitis. After pancreatitis subsided, the patient was put on chemotherapy. Unfortunately, due to immunocompromise, he died of pneumonia and sepsis. There was no reasonable explanation regarding to the cause of acute pancreatitis except hypercalcemia, which might be due to SCLC with bone metastasis. This is the first report of such a complication in a patient with SCLC.


Subject(s)
Bone Neoplasms/secondary , Carcinoma, Small Cell/complications , Hypercalcemia/etiology , Liver Neoplasms/secondary , Lung Neoplasms/complications , Pancreatitis/etiology , Acute Disease , Aged , Humans , Male
17.
Ann Plast Surg ; 33(4): 439-41, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7810965

ABSTRACT

An adipofascial turnover flap is described. This vascularized flap is technically simple to perform and provides excellent cosmetic results for patients with a very large tumor undergoing superficial parotidectomy. The flap also acts as a barrier for regenerating nerves, preventing the development of gustatory sweating.


Subject(s)
Adenoma, Pleomorphic/surgery , Parotid Neoplasms/surgery , Surgical Flaps , Adult , Female , Humans , Parotid Gland/surgery , Surgical Flaps/methods
18.
Hepatogastroenterology ; 41(1): 30-3, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8175110

ABSTRACT

To evaluate the diagnostic value of a method combining ultrasonically-guided Chiba needle aspiration and histological block preparation of aspiration specimen, 50 consecutive patients with histologically confirmed focal or diffuse lesion of the liver were studied. In addition to conventional aspiration cytology, the aspiration specimen was mixed 1:1 by volume with 95% alcohol and centrifuged. The precipitated specimen was then embedded in paraplast. Serial sections were obtained and stained with hematoxylin and eosin (H & E) technique. The diagnostic specificity and positive predictive value of the cell block technique in diagnosing hepatic malignancies were both 100%, as was those of aspiration cytology. The diagnostic sensitivity and overall accuracy of cell blocks were significantly better than those of aspiration cytology (89.5% vs. 63.2%, P < 0.01; and 92.0% vs. 72.0%, P < 0.01). The negative predictive value of cell blocks was also better than that of aspiration cytology, but the difference was not statistically significant (75.0% vs. 46.2%, P > 0.05). In terms of cellular differentiation, the accuracy of the diagnosis of cell blocks was 78.6% (22/28) in hepatoma; 80.0% (4/5) in metastatic adenocarcinoma and 100.0% (1/1) in small cell carcinoma. No complications were encountered in any of the patients. The results suggest that the preparation of cell blocks of the aspiration specimen is a reliable and accurate method for the diagnosis of hepatic malignancies. This method also elevates the diagnosis of the aspiration specimen from the cytological to the histopathological level.


Subject(s)
Biopsy, Needle , Liver Neoplasms/diagnosis , Ultrasonography, Interventional , Adult , Aged , Cytodiagnosis , Cytological Techniques , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity
19.
Am J Trop Med Hyg ; 47(3): 265-70, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1355950

ABSTRACT

The impact of dengue on liver function was studied by biochemical tests on 125 male and 145 female patients diagnosed with this disease during an outbreak that extended from November 1987 to December 1988. Abnormal levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase (G-GT) were observed in 93.3%, 82.2%, 7.2%, 16.3% and 83.0% of the patients, respectively. The elevation of transaminases was mild to moderate in most cases, but was 10-fold greater than the normal upper limit for AST and ALT in 11.1% and 7.4% of the patients, respectively. Initially, the level of AST was greater than that of ALT, increasing to maximum levels nine days after the onset of symptoms, then decreasing to normal levels within two weeks. Results of the biochemical tests did not differ significantly between the cases with and without hepatitis B or hepatitis C virus infection, but significantly higher elevations of AST, ALT, and G-GT were observed in patients with episodes of bleeding. Liver biopsies of two patients showed features of lobular hepatitis. Of the five fatal cases, three died of hepatic failure. It is concluded that dengue fever may cause hepatic injury and transaminase elevation similar to that in patients with conventional viral hepatitis. In epidemic or endemic areas, dengue fever infection should be considered in the differential diagnosis of hepatitis.


Subject(s)
Dengue/diagnosis , Hepatitis, Viral, Human/diagnosis , Liver/pathology , Transaminases/blood , Adolescent , Adult , Aged , Alanine Transaminase/blood , Alkaline Phosphatase/blood , Aspartate Aminotransferases/blood , Bilirubin/blood , Biopsy , Dengue/blood , Dengue/pathology , Diagnosis, Differential , Female , Hepatitis B Surface Antigens/blood , Hepatitis, Viral, Human/blood , Hepatitis, Viral, Human/pathology , Humans , Liver Function Tests , Male , Middle Aged , Platelet Count , Retrospective Studies , gamma-Glutamyltransferase/blood
20.
Changgeng Yi Xue Za Zhi ; 15(3): 161-6, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1468040

ABSTRACT

Esophageal carcinosarcoma is a rare malignant tumor. The tumor is composed of both carcinomatous and sarcomatous elements. The multiple designations of names such as pseudosarcoma, pseudosarcomatous carcinoma, polypoid carcinoma etc. reflect the controversy on the nature of sarcomatous component of this lesion. We report a case of carcinosarcoma of esophagus occurred in a 67 year old male with progressive dysphagia. Esophageal polypoid tumor was found by endoscopy and was resected by esophagectomy. Carcinosarcoma was proved by demonstrating both carcinomatous and sarcomatous components in the tumor. Immunohistochemical studies revealed positive keratin stain in the sarcomatous area and positive vimentin stain in the sarcomatous area. The tumor was reported to have a better prognosis than that of the squamous cell carcinoma of esophagus in the literatures, especially in the survival rate.


Subject(s)
Carcinosarcoma/pathology , Esophageal Neoplasms/pathology , Aged , Carcinosarcoma/chemistry , Carcinosarcoma/mortality , Esophageal Neoplasms/chemistry , Esophageal Neoplasms/mortality , Humans , Male , Survival Rate , Vimentin/analysis
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