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1.
Obstet Med ; 6(2): 80-82, 2013 Jun.
Article in English | MEDLINE | ID: mdl-27757162

ABSTRACT

We present a case report of a successful pregnancy outcome in a woman diagnosed with Ehlers-Danlos syndrome (EDS) hypermobility type or type III. EDS is a group of connective tissue disorders that has a common genotypic defect, but heterogeneous phenotypic presentations. The variation in EDS manifestations can result in moderate to severe effects on life-expectancy for some types. A number of studies and a review of the literature indicate that generally in pregnant women with EDS, maternal and neonatal outcomes are favourable. However, in EDS type IV, pregnancy can be associated with serious maternal complications. Therefore, obstetrical management should be individualized. This paper discusses the obstetric management of a patient with EDS hypermobility type and compares it to other studies in the literature.

2.
Prev Vet Med ; 110(3-4): 525-40, 2013 Jul 01.
Article in English | MEDLINE | ID: mdl-23484803

ABSTRACT

A cost-benefit analysis using deterministic and stochastic modelling was conducted to identify the net benefits for households that adopt (1) vaccination of individual birds against Newcastle disease (ND) or (2) improved management of chick rearing by providing coops for the protection of chicks from predation and chick starter feed inside a creep feeder to support chicks' nutrition in village chicken flocks in Myanmar. Partial budgeting was used to assess the additional costs and benefits associated with each of the two interventions tested relative to neither strategy. In the deterministic model, over the first 3 years after the introduction of the interventions, the cumulative sum of the net differences from neither strategy was 13,189Kyat for ND vaccination and 77,645Kyat for improved chick management (effective exchange rate in 2005: 1000Kyat=1$US). Both interventions were also profitable after discounting over a 10-year period; Net Present Values for ND vaccination and improved chick management were 30,791 and 167,825Kyat, respectively. The Benefit-Cost Ratio for ND vaccination was very high (28.8). This was lower for improved chick management, due to greater costs of the intervention, but still favourable at 4.7. Using both interventions concurrently yielded a Net Present Value of 470,543Kyat and a Benefit-Cost Ratio of 11.2 over the 10-year period in the deterministic model. Using the stochastic model, for the first 3 years following the introduction of the interventions, the mean cumulative sums of the net difference were similar to those values obtained from the deterministic model. Sensitivity analysis indicated that the cumulative net differences were strongly influenced by grower bird sale income, particularly under improved chick management. The effects of the strategies on odds of households selling and consuming birds after 7 months, and numbers of birds being sold or consumed after this period also influenced profitability. Cost variations for equipment used under improved chick management were not markedly associated with profitability. Net Present Values and Benefit-Cost Ratios discounted over a 10-year period were also similar to the deterministic model when mean values obtained through stochastic modelling were used. In summary, the study showed that ND vaccination and improved chick management can improve the viability and profitability of village chicken production in Myanmar.


Subject(s)
Animal Husbandry/methods , Chickens , Communicable Disease Control/methods , Newcastle Disease/prevention & control , Poultry Diseases/prevention & control , Animal Husbandry/economics , Animals , Communicable Disease Control/economics , Cost-Benefit Analysis , Models, Theoretical , Myanmar , Newcastle Disease/economics , Newcastle Disease/virology , Poultry Diseases/economics , Poultry Diseases/virology , Stochastic Processes , Vaccination/economics , Vaccination/veterinary
3.
Prev Vet Med ; 90(1-2): 17-30, 2009 Jul 01.
Article in English | MEDLINE | ID: mdl-19443062

ABSTRACT

Previous research identified Newcastle disease and poor management of chicks (birds younger than 6 weeks of age) as major constraints to village chicken production in Myanmar. Based on these findings, controlled trials were conducted in 124 randomly selected households in nine villages in Myanmar over a period of 12 months to evaluate strategies to enhance survival of village chickens. Two intervention strategies were assessed: Newcastle disease vaccination using the thermostable I-2 vaccine and changes to the management of chick rearing (confinement and supplementary feeding). These interventions were applied in two trials: (1) a randomised controlled trial to compare I-2 vaccination, altered chick management and no intervention (apart from placebo treatment) at household level and (2) nested within this trial, a double-blinded controlled trial at bird-level to compare serological titres between I-2 vaccinated and placebo-treated birds both between and within households. Outcomes measured in the first trial were crude incidence rate of mortality, proportional mortality rate for deaths due to disease stratified by age group of birds and mortality attributed to Newcastle disease, number of sales, income from sale of birds, consumption of birds and hatching of birds. Odds of having protective titres two weeks after vaccination were up to 125 times higher in I-2 vaccinated birds and up to 47 times higher in control birds in contact with I-2 vaccinates compared to birds without I-2 contact. Vaccination against Newcastle disease reduced the proportions of mortalities assumed to be caused by disease in growers and chicks. Crude mortality incidence was lower in households that applied management changes to chick rearing. In household-months when birds were sold, numbers sold were higher and income from sale of birds were about 2.50 US dollars per month higher in households allocated to altered chick management. Altered chick management resulted in more households having hatchings of chicks. After a lag period of 7 months, these households were also more likely to consume home-produced chicken meat. This 7-month period reflects the age when birds are consumed and sold and highlights the lag periods that should be expected before beneficial effects of interventions focussed on chicks occur. This field research has shown that I-2 vaccination markedly increases the prevalence of protective titres and reduces proportions of mortality attributed to disease and that chick management using confinement and supplementary feeding can improve health and production of village chickens. These interventions are simple and sustainable intervention strategies.


Subject(s)
Animal Husbandry , Chickens , Newcastle Disease/prevention & control , Newcastle disease virus/immunology , Poultry Diseases/prevention & control , Viral Vaccines/administration & dosage , Animal Husbandry/economics , Animal Husbandry/methods , Animal Husbandry/standards , Animals , Antibodies, Viral/blood , Female , Male , Myanmar/epidemiology , Newcastle Disease/epidemiology , Newcastle Disease/mortality , Poultry Diseases/epidemiology , Poultry Diseases/mortality , Treatment Outcome
4.
Prev Vet Med ; 85(3-4): 241-52, 2008 Jul 15.
Article in English | MEDLINE | ID: mdl-18367272

ABSTRACT

Village chickens are an important livestock for many rural families in Myanmar and other developing countries. Village chickens are kept under free-ranging conditions, with confinement only at night. Therefore, it is likely that some deaths are not observed by farmers. We conducted a longitudinal study from November 2003 until May 2004 to describe temporal patterns of mortality of village chickens in 10 villages in Myanmar. Field veterinarians first identified the numbers of birds in all chicken-owning households in each village. We then selected 307 households randomly with stratification by flock size. Each study household was then visited once monthly at which time questionnaires were completed recording current flock structure and numbers of hatchings, mortalities, sales and birds consumed since the previous visit. In addition, sera were collected from a sample of adult birds and growers. Depending on month and age group of chicken, from 71 to 231 (out of 290-307) households had discrepancies in the counts of birds. For chicks, at least one-quarter of the households had unobserved losses of at least 5 chicks per household (maximum 66 chicks); unobserved losses were less for growers and adult chickens. The median month-specific, village-specific mortality rates per 1000 bird-days at risk (counting missing birds as deaths) ranged from 0.8 to 1.7 for adults, from 0.4 to 4.7 for growers and from 8.0 to 16.5 for chicks. Across all birds, the prevalence of protective titres against Newcastle disease virus was 79% (95% confidence interval 74, 84); higher prevalences of protective titres were associated with reduced mortality rates in the following months.


Subject(s)
Chickens , Newcastle Disease/mortality , Newcastle disease virus/isolation & purification , Animals , Antibodies, Viral/blood , Hemagglutination Inhibition Tests/veterinary , Longitudinal Studies , Myanmar/epidemiology , Newcastle Disease/epidemiology , Newcastle Disease/immunology , Newcastle Disease/virology , Newcastle disease virus/immunology , Rural Population , Seroepidemiologic Studies
5.
Trop Anim Health Prod ; 38(7-8): 611-8, 2006.
Article in English | MEDLINE | ID: mdl-17265778

ABSTRACT

There is a variety of professions working with village chickens in developing countries, including farmers, veterinarians and chicken traders. People from all these occupations were involved in a participatory rural appraisal to investigate husbandry practices and trade of village chickens in Myanmar. Data were collected in two climatically different regions of the country, in the Yangon and in the Mandalay divisions. The breeding and training of fighting cocks was practised only in the Mandalay division, with well-trained birds sold for very high prices. Apart from this, chickens were raised in both regions mainly for small disposable income and were generally sold when money was needed, in particular during religious festivals. Chicken traders on bicycles, often called 'middle men', usually purchase birds from farmers in about 10 villages per day. Several 'middle men' supply birds to wealthier chicken merchants, who sell these birds at larger chicken markets. There is in general limited knowledge among farmers about the prevention of Newcastle disease via vaccination. Commercial indigenous chicken production is practised in Myanmar, but family poultry farming dominates indigenous chicken production in the country.


Subject(s)
Animal Husbandry/economics , Animal Husbandry/methods , Chickens , Poultry Diseases/prevention & control , Vaccination/veterinary , Animals , Climate , Eggs/economics , Female , Income , Male , Myanmar , Newcastle Disease/prevention & control , Reproduction , Rural Population
6.
J Cell Mol Med ; 7(3): 207-22, 2003.
Article in English | MEDLINE | ID: mdl-14594546

ABSTRACT

Cyclooxygenase (COX)-2 and the prostaglandins resulting from its enzymatic activity have been shown to play a role in modulating cell growth and development of human neoplasia. Evidence includes a direct relationship between COX-2 expression and cancer incidence in humans and animal models, increased tumorigenesis after genetic manipulation of COX-2, and significant anti-tumor properties of non-steroidal anti-inflammatory drugs in animal models and in some human cancers. Recent data showed that COX-2 and the derived prostaglandins are involved in control of cellular growth, apoptosis, and signal through a group of nuclear receptors named peroxisome proliferator-activated receptors (PPARs). In this article we will review some of the findings suggesting that COX-2 is involved in multiple cellular mechanisms that lead to tumorigenesis.


Subject(s)
Cell Division/physiology , Cell Transformation, Neoplastic , Isoenzymes/metabolism , Prostaglandin-Endoperoxide Synthases/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Antineoplastic Agents/metabolism , Apoptosis/physiology , Cyclooxygenase 2 , Cyclooxygenase 2 Inhibitors , Cyclooxygenase Inhibitors/metabolism , Gene Expression Regulation, Enzymologic , Humans , Isoenzymes/genetics , Membrane Proteins , Prostaglandin-Endoperoxide Synthases/genetics , Prostaglandins/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Transcription Factors/metabolism
7.
Science ; 294(5548): 1875-8, 2001 Nov 30.
Article in English | MEDLINE | ID: mdl-11729304

ABSTRACT

Upon cell activation, membrane phospholipids are metabolized into potent lysophospholipid (LP) mediators, such as sphingosine 1-phosphate and lysophosphatidic acid. LPs fulfill signaling roles in organisms as diverse as yeast and humans. The recent discovery of G protein-coupled receptors for LPs in higher eukaryotes, and their involvement in regulating diverse processes such as angiogenesis, cardiac development, neuronal survival, and immunity, has stimulated growing interest in these lipid mediators. LP receptor biology has generated insights into fundamental cellular mechanisms and may provide therapeutic targets for drug development.


Subject(s)
Lysophospholipids/metabolism , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled , Sphingosine/analogs & derivatives , Sphingosine/metabolism , Animals , Heterotrimeric GTP-Binding Proteins/antagonists & inhibitors , Heterotrimeric GTP-Binding Proteins/metabolism , Humans , Lysophospholipids/antagonists & inhibitors , Phylogeny , Receptors, Cell Surface/antagonists & inhibitors , Receptors, Lysophosphatidic Acid , Receptors, Lysophospholipid , Signal Transduction , Sphingosine/antagonists & inhibitors
8.
Anticancer Res ; 21(4A): 2471-6, 2001.
Article in English | MEDLINE | ID: mdl-11724309

ABSTRACT

The peroxisome proliferator-activated receptor (PPAR)-gamma is a member of the steroid nuclear receptors. Recent studies have demonstrated that PPAR-gamma is expressed in several cancer cells. We examined the PPAR-gamma expression in both normal lung and major types of human lung cancer. The expression of PPAR-gamma mRNA was detected in 2 out of 3 normal lung tissues and its protein was detected in 3 out of 5 normal lung tissues. In contrast, a small cell carcinoma cell line and all other types of lung cancer tissues expressed PPAR-gamma mRNA and its protein. Immunoreactive PPAR-gamma is strongly expressed in cancer cells and moderately in mononuclear cells, endothelial cells and fibroblasts of lung cancer tissues. Our results suggest that PPAR-gamma may play an important role in the pathogenesis and/or progression of lung cancer, and may be a novel therapeutical target for therapy of lung cancer.


Subject(s)
Lung Neoplasms/metabolism , Receptors, Cytoplasmic and Nuclear/biosynthesis , Transcription Factors/biosynthesis , Aged , Aged, 80 and over , Blotting, Western , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Small Cell/genetics , Carcinoma, Small Cell/metabolism , Carcinoma, Small Cell/pathology , Female , Humans , Immunohistochemistry , Lung/metabolism , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Male , Middle Aged , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptors, Cytoplasmic and Nuclear/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/genetics
9.
Mol Cell ; 8(3): 693-704, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11583630

ABSTRACT

The role of the protein kinase Akt in cell migration is incompletely understood. Here we show that sphingosine-1-phosphate (S1P)-induced endothelial cell migration requires the Akt-mediated phosphorylation of the G protein-coupled receptor (GPCR) EDG-1. Activated Akt binds to EDG-1 and phosphorylates the third intracellular loop at the T(236) residue. Transactivation of EDG-1 by Akt is not required for G(i)-dependent signaling but is indispensable for Rac activation, cortical actin assembly, and chemotaxis. Indeed, T236AEDG-1 mutant sequestered Akt and acted as a dominant-negative GPCR to inhibit S1P-induced Rac activation, chemotaxis, and angiogenesis. Transactivation of GPCRs by Akt may constitute a specificity switch to integrate rapid G protein-dependent signals into long-term cellular phenomena such as cell migration.


Subject(s)
Chemotaxis/physiology , Endothelium, Vascular/cytology , Immediate-Early Proteins/metabolism , Lysophospholipids , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/metabolism , Receptors, G-Protein-Coupled , Signal Transduction/physiology , Actins/metabolism , Animals , Cell Line , Endothelium, Vascular/drug effects , Enzyme Activation/physiology , Humans , Models, Biological , Neovascularization, Physiologic/physiology , Phosphorylation , Protein Binding , Protein Structure, Tertiary , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-akt , Receptors, Cell Surface , Receptors, Lysophospholipid , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sphingosine/analogs & derivatives , Sphingosine/pharmacology , rac GTP-Binding Proteins/genetics , rac GTP-Binding Proteins/metabolism
10.
Circ Res ; 89(6): 496-502, 2001 Sep 14.
Article in English | MEDLINE | ID: mdl-11557736

ABSTRACT

Sphingosine 1-phosphate (S1P), a platelet-derived ligand for the EDG-1 family of G protein-coupled receptors (GPCRs), has recently emerged as a regulator of vascular development. Although S1P has potent effects on endothelial cells and vascular smooth muscle cells (VSMCs), the functions of the specific S1P receptors in the latter cell type are not known. Here we show that pup-intimal VSMCs express higher levels of EDG-1 mRNA than adult-medial VSMCs. Stable transfection of EDG-1 into adult-medial VSMCs enhanced their proliferative response to S1P, concomitant with induction of p70 S6 kinase activity and expression of cyclin D1. Pertussis toxin treatment inhibited S1P-induced p70 S6 kinase activation, cyclin D1 expression and proliferation, suggesting that EDG-1-coupling to the G(i) pathway is critical. Furthermore, blocking p70 S6 kinase phosphorylation with rapamycin inhibited cyclin D1 expression and proliferation, suggesting that activation of p70 S6 kinase is critical in EDG-1/G(i)-mediated cell proliferation. EDG-1 expression also profoundly enhanced the migratory response of adult-medial VSMCs to S1P. S1P-induced migration of adult-medial VSMCs expressing exogenous EDG-1 required G(i) activation but not p70 S6 kinase. These results suggest that enhanced expression of EDG-1 in VSMCs dramatically stimulates both the proliferative and migratory responses to S1P. Since EDG-1 is expressed in the pup-intimal phenotype of VSMCs, S1P signaling via EDG-1 may play a role in vascular diseases in which the proliferation and migration of VSMCs are dysregulated.


Subject(s)
Immediate-Early Proteins/physiology , Lysophospholipids , Muscle, Smooth, Vascular/cytology , Receptors, Cell Surface , Receptors, G-Protein-Coupled , Animals , Animals, Newborn , Cell Division/drug effects , Cell Movement/drug effects , Cells, Cultured , Culture Media, Serum-Free/pharmacology , Cyclin D1/drug effects , Cyclin D1/metabolism , DNA/biosynthesis , DNA/drug effects , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , Gene Expression Regulation/drug effects , Immediate-Early Proteins/genetics , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Pertussis Toxin , Protein Isoforms/genetics , RNA, Messenger/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Receptors, Lysophospholipid , Ribosomal Protein S6 Kinases/drug effects , Ribosomal Protein S6 Kinases/metabolism , Sirolimus/pharmacology , Sphingosine/analogs & derivatives , Sphingosine/pharmacology , Transfection , Virulence Factors, Bordetella/pharmacology
11.
Biochem Biophys Res Commun ; 283(4): 750-5, 2001 May 18.
Article in English | MEDLINE | ID: mdl-11350047

ABSTRACT

Rheumatoid arthritis (RA) is a chronic polyarticular joint disease associated with massive synovial proliferation, inflammation, and angiogenesis. PPAR-gamma ligands, both 15-deoxy-Delta(12,14)-prostaglandin J2 (15d- PGJ2) and troglitazone (TRO), can inhibit the growth of RA synoviocytes in vitro, and suppress the chronic inflammation of adjuvant-induced arthritis in rats, but the potency of 15d-PGJ2 is higher than TRO. Prostaglandin (PG) E2 plays important roles in joint erosion and synovial inflammation. In the present study, 15d-PGJ2, but not TRO and other prostanoids, suppressed interleukin (IL)-1beta-induced PGE2 synthesis in rheumatoid synovial fibroblasts (RSFs) through the inhibition of cyclooxygenase (COX-2) and cytosolic phospholipase A2 (cPLA2) expression. Furthermore, the inhibition was not affected by pretreatment with anti-PPAR-gamma antibody. It means that this anti-inflammatory effect of 15d-PGJ2 for PG synthesis may be independent of PPAR-gamma and 15d-PGJ2 is a key regulator of negative feedback of the arachidonate cascade on the COX pathway. These findings provide new insight into the feedback mechanism of the arachidonate cascade.


Subject(s)
Arachidonic Acid/metabolism , Arthritis, Rheumatoid/metabolism , Feedback , Prostaglandin D2/metabolism , Synovial Membrane/metabolism , Thiazolidinediones , Arthritis, Rheumatoid/pathology , Chromans/pharmacology , Cyclooxygenase 2 , Cysteine/antagonists & inhibitors , Cysteine/biosynthesis , Dinoprostone/antagonists & inhibitors , Dinoprostone/biosynthesis , Humans , Isoenzymes/immunology , Isoenzymes/metabolism , Leukotriene Antagonists , Leukotriene B4/antagonists & inhibitors , Leukotriene B4/biosynthesis , Leukotrienes/biosynthesis , Membrane Proteins , Prostaglandin D2/analogs & derivatives , Prostaglandin-Endoperoxide Synthases/immunology , Prostaglandin-Endoperoxide Synthases/metabolism , Receptors, Cytoplasmic and Nuclear/immunology , Thiazoles/pharmacology , Transcription Factors/immunology , Troglitazone
12.
Prostaglandins Other Lipid Mediat ; 64(1-4): 135-42, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11324703

ABSTRACT

Sphingosine-1-phosphate (SPP) is a bioactive lipid produced from the metabolism of sphingomyelin. It is an important constituent of serum and regulates cell growth, survival, migration, differentiation and gene expression. Its mode of action has been enigmatic; however, recent findings have shown that a family of G-protein-coupled receptors (GPCR) of the endothelial differentiation gene (EDG) family serve as plasma membrane-localized receptors for SPP. Furthermore, the EDG receptors appear to be SPP receptor subtypes with distinct signaling characteristics. In vascular endothelial cells, SPP acts on EDG-1 and EDG-3 subtypes of receptors to induce cell survival and morphogenesis. Such pathways appear to be critical for SPP-induced angiogenic response in vivo. In addition, the EDG-1 gene is essential for vascular maturation in development. Moreover, developmental studies in Zebrafish have indicated that SPP signaling via the EDG-5 like receptor Miles Apart (Mil) is essential for heart development. These data strongly suggest that a physiological role of SPP is in the formation of the cardiovascular system. Despite these recent findings, much needs to be clarified with respect to the physiological role of SPP synthesis and action. This review will focus on the recent findings on SPP receptors and the effects on the cardiovascular system.


Subject(s)
Lysophospholipids , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled , Sphingosine/metabolism , Receptors, Lysophospholipid , Signal Transduction , Sphingosine/analogs & derivatives
13.
J Biol Chem ; 276(22): 19672-7, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11278592

ABSTRACT

Sphingosine 1-phosphate (SPP) binds to members of the endothelial differentiation gene family (EDG) of receptors and leads to diverse signaling events including cell survival, growth, migration and differentiation. However, the mechanisms of how SPP activates these proangiogenic pathways are poorly understood. Here we show that SPP signals through the EDG-1 receptor to the heterotrimeric G protein G(i), leading to activation of the serine/threonine kinase Akt and phosphorylation of the Akt substrate, endothelial nitric-oxide synthase (eNOS). Inhibition of G(i) signaling, and phosphoinositide 3-kinase (PI 3-kinase) activity resulted in a decrease in SPP-induced endothelial cell chemotaxis. SPP also stimulates eNOS phosphorylation and NO release and these effects are also attenuated by inhibition of G(i) signaling, PI 3-kinase, and Akt. However, inhibition of NO production did not influence SPP-induced chemotaxis but effectively blocked the chemotactic actions of vascular endothelial growth factor. Thus, SPP signals through G(i) and PI 3-kinase leading to Akt activation and eNOS phosphorylation.


Subject(s)
Chemotaxis , Endothelium, Vascular/cytology , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism , Lysophospholipids , Nitric Oxide/biosynthesis , Phosphatidylinositol 3-Kinases/metabolism , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/metabolism , Sphingosine/metabolism , Sphingosine/physiology , Animals , Blotting, Northern , Blotting, Western , Cattle , Cell Movement , Culture Media, Serum-Free/metabolism , Dose-Response Relationship, Drug , Endothelial Growth Factors/pharmacology , Endothelium, Vascular/enzymology , Enzyme Activation , Genes, Dominant , Lung/metabolism , Lymphokines/pharmacology , Neovascularization, Physiologic , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type III , Phosphorylation , Protein Binding , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-akt , Receptors, Cell Surface/biosynthesis , Signal Transduction , Sphingosine/analogs & derivatives , Time Factors , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors , Virulence Factors, Bordetella/pharmacology
14.
J Biol Chem ; 276(21): 18563-9, 2001 May 25.
Article in English | MEDLINE | ID: mdl-11278747

ABSTRACT

The cyclooxygenase (COX)-2 gene encodes an inducible prostaglandin synthase enzyme that is overexpressed in adenocarcinomas and other tumors. Deletion of the murine Cox-2 gene in Min mice reduced the incidence of intestinal tumors, suggesting that it is required for tumorigenesis. However, it is not known if overexpression of Cox-2 is sufficient to induce tumorigenic transformation. We have derived transgenic mice that overexpress the human COX-2 gene in the mammary glands using the murine mammary tumor virus promoter. The human Cox-2 mRNA and protein are expressed in mammary glands of female transgenic mice and were strongly induced during pregnancy and lactation. Female virgin Cox-2 transgenic mice showed precocious lobuloalveolar differentiation and enhanced expression of the beta-casein gene, which was inhibited by the Cox inhibitor indomethacin. Mammary gland involution was delayed in Cox-2 transgenic mice with a decrease in apoptotic index of mammary epithelial cells. Multiparous but not virgin females exhibited a greatly exaggerated incidence of focal mammary gland hyperplasia, dysplasia, and transformation into metastatic tumors. Cox-2-induced tumor tissue expressed reduced levels of the proapoptotic proteins Bax and Bcl-x(L) and an increase in the anti-apoptotic protein Bcl-2, suggesting that decreased apoptosis of mammary epithelial cells contributes to tumorigenesis. These data indicate that enhanced Cox-2 expression is sufficient to induce mammary gland tumorigenesis. Therefore, inhibition of Cox-2 may represent a mechanism-based chemopreventive approach for carcinogenesis.


Subject(s)
Isoenzymes/genetics , Mammary Neoplasms, Experimental/etiology , Mammary Neoplasms, Experimental/genetics , Prostaglandin-Endoperoxide Synthases/genetics , Animals , Cyclooxygenase 2 , Female , Gene Expression Regulation, Enzymologic , Isoenzymes/biosynthesis , Mammary Neoplasms, Experimental/enzymology , Mice , Mice, Transgenic , Prostaglandin-Endoperoxide Synthases/biosynthesis
15.
Lung Cancer ; 31(2-3): 203-12, 2001.
Article in English | MEDLINE | ID: mdl-11165399

ABSTRACT

The effects of prostaglandin E2 (PGE2) and vasoactive intestinal peptide (VIP) on vascular endothelial cell growth factor (VEGF) mRNAs were investigated using lung cancer cells. By RT-PCR, VEGF(121), VEGF(165), and VEGF(189), but not VEGF(206) isoforms were detected in all lung cancer cell lines and biopsy specimens examined. By Northern blot, VEGF mRNA was detected in all small cell lung cancer (SCLC) and non-SCLC (NSCLC) cell lines examined. PGE2, VIP and forskolin caused increased VEGF expression in a time- and concentration-dependent manner using NSCLC cell line NCI-H157. Approximately 1 microM PGE2, 0.1 microM VIP and 50 microM forskolin caused cAMP elevation, 64-, 33- and 128-fold, respectively, using NCI-H157 cells after 5 min. The increase in cAMP caused by PGE(2) and VIP was reversed by somatostatin (SST). Also 1 microM PGE2, 0.1 microM VIP and 50 microM forskolin increased the VEGF mRNA 2.0-, 1.5- and 2.3-fold, respectively, after 4 h. The increase in VEGF mRNA caused by PGE2, VIP and forskolin was inhibited by H-89, a protein kinase A inhibitor. A VIP receptor antagonist, VIPhybrid, inhibited the increase in cAMP and VEGF mRNA caused by VIP. By ELISA, VEGF was detected in the conditioned media exposed to the lung cancer cell lines. These results suggest that VEGF synthesis in and secretion from lung cancer cells can be regulated by agents, which cause adenylyl cyclase activation.


Subject(s)
Adenylyl Cyclases/metabolism , Carcinoma, Non-Small-Cell Lung/physiopathology , Carcinoma, Small Cell/physiopathology , Dinoprostone/pharmacology , Lung Neoplasms/physiopathology , Receptor Protein-Tyrosine Kinases/biosynthesis , Receptors, Growth Factor/biosynthesis , Vasoactive Intestinal Peptide/pharmacology , Colforsin/pharmacology , Culture Media , DNA, Neoplasm/analysis , Enzyme-Linked Immunosorbent Assay , Humans , RNA, Messenger/analysis , Receptors, Vascular Endothelial Growth Factor , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured
16.
J Biol Chem ; 276(15): 11830-7, 2001 Apr 13.
Article in English | MEDLINE | ID: mdl-11150298

ABSTRACT

Sphingosine 1-phosphate (SPP), a platelet-derived bioactive lysophospholipid, is a regulator of angiogenesis. However, molecular mechanisms involved in SPP-induced angiogenic responses are not fully defined. Here we report the molecular mechanisms involved in SPP-induced human umbilical vein endothelial cell (HUVEC) adhesion and migration. SPP-induced HUVEC migration is potently inhibited by antisense phosphothioate oligonucleotides against EDG-1 as well as EDG-3 receptors. In addition, C3 exotoxin blocked SPP-induced cell attachment, spreading and migration on fibronectin-, vitronectin- and Matrigel-coated surfaces, suggesting that endothelial differentiation gene receptor signaling via the Rho pathway is critical for SPP-induced cell migration. Indeed, SPP induced Rho activation in an adherence-independent manner, whereas Rac activation was dispensible for cell attachment and focal contact formation. Interestingly, both EDG-1 and -3 receptors were required for Rho activation. Since integrins are critical for cell adhesion, migration, and angiogenesis, we examined the effects of blocking antibodies against alpha(v)beta(3), beta(1), or beta(3) integrins. SPP induced Rho-dependent integrin clustering into focal contact sites, which was essential for cell adhesion, spreading and migration. Blockage of alpha(v)beta(3)- or beta(1)-containing integrins inhibited SPP-induced HUVEC migration. Together our results suggest that endothelial differentiation gene receptor-mediated Rho signaling is required for the activation of integrin alpha(v)beta(3) as well as beta(1)-containing integrins, leading to the formation of initial focal contacts and endothelial cell migration.


Subject(s)
DNA-Binding Proteins/metabolism , Endothelium, Vascular/cytology , I-kappa B Proteins , Immediate-Early Proteins/metabolism , Integrin beta1/metabolism , Lysophospholipids , Receptors, Cell Surface , Receptors, G-Protein-Coupled , Receptors, Vitronectin/metabolism , Sphingosine/physiology , Base Sequence , Cells, Cultured , DNA Primers , Endothelium, Vascular/metabolism , Enzyme Activation , Fibrin/metabolism , GTP Phosphohydrolases/metabolism , Humans , Immunohistochemistry , NF-KappaB Inhibitor alpha , Receptors, Lysophospholipid , Sphingosine/analogs & derivatives
18.
Eur J Pediatr ; 160(12): 726-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11795680

ABSTRACT

UNLABELLED: Two patients are described with acute collapse caused by pericardial effusion following central venous catheterisation. Echocardiography during resuscitation allowed prompt identification and management. CONCLUSION: Pericardial effusion should be considered in any baby experiencing acute deterioration with a central venous catheter in place.


Subject(s)
Catheterization, Central Venous/adverse effects , Pericardial Effusion/diagnostic imaging , Echocardiography , Female , Humans , Infant, Newborn , Male , Obstetric Labor, Premature , Pericardial Effusion/etiology , Pericardial Effusion/therapy , Pericardiocentesis , Pregnancy
19.
J Clin Invest ; 106(8): 951-61, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11032855

ABSTRACT

Sphingolipid signaling pathways have been implicated in many critical cellular events. Sphingosine-1-phosphate (SPP), a sphingolipid metabolite found in high concentrations in platelets and blood, stimulates members of the endothelial differentiation gene (Edg) family of G protein-coupled receptors and triggers diverse effects, including cell growth, survival, migration, and morphogenesis. To determine the in vivo functions of the SPP/Edg signaling pathway, we disrupted the Edg1 gene in mice. Edg1(-/-) mice exhibited embryonic hemorrhage leading to intrauterine death between E12.5 and E14.5. Vasculogenesis and angiogenesis appeared normal in the mutant embryos. However, vascular maturation was incomplete due to a deficiency of vascular smooth muscle cells/pericytes. We also show that Edg-1 mediates an SPP-induced migration response that is defective in mutant cells due to an inability to activate the small GTPase, Rac. Our data reveal Edg-1 to be the first G protein-coupled receptor required for blood vessel formation and show that sphingolipid signaling is essential during mammalian development.


Subject(s)
Cardiovascular System/embryology , GTP-Binding Proteins/metabolism , Immediate-Early Proteins/genetics , Lysophospholipids , Muscle, Smooth, Vascular/embryology , Receptors, Cell Surface , Receptors, G-Protein-Coupled , Sphingosine/analogs & derivatives , Animals , Blood Vessels/embryology , Cell Movement , Fibroblasts/cytology , Fibroblasts/drug effects , Heart/embryology , Homozygote , Mice , Mice, Knockout , Phenotype , Receptors, Lysophospholipid , Signal Transduction , Sphingosine/metabolism , Sphingosine/pharmacology
20.
Br J Pharmacol ; 131(4): 651-4, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11030710

ABSTRACT

Peroxisome proliferator activated receptors (PPAR)s are nuclear transcription factors of the steroid receptor super-family. One member, PPARgamma, a critical transcription factor in adipogenesis, is expressed in ECV304 cells, and when activated participates in the induction of cell death by apoptosis. Here we describe a clone of ECV304 cells, ECV-ACO.Luc, which stably expresses a reporter gene for PPAR activation. ECV-ACO.Luc respond to the PPARgamma agonists, 15-deoxy-Delta(12,14) PGJ(2), and ciglitizone, by inducing luciferase expression. Furthermore, using ECV-ACO.Luc, we demonstrate that a newly described PPARgamma antagonist, bisphenol A diglycidyl ether (BADGE) has agonist activities. Similar to 15-deoxy-Delta(12,14) PGJ(2), BADGE induces PPARgamma activation, nuclear localization of the receptor, and induces cell death.


Subject(s)
Epoxy Compounds/pharmacology , Receptors, Cytoplasmic and Nuclear/agonists , Transcription Factors/agonists , Benzhydryl Compounds , Cell Death/drug effects , Cell Line , Cell Nucleus/chemistry , Humans , Luciferases/genetics , Receptors, Cytoplasmic and Nuclear/analysis , Receptors, Cytoplasmic and Nuclear/physiology , Transcription Factors/analysis , Transcription Factors/physiology
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