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1.
J Psychiatr Ment Health Nurs ; 21(8): 746-54, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25356465

ABSTRACT

Much of the literature on eating disorders deals with Western subjects. Although the majority of those seen in clinical settings are Caucasians, reports from Asia suggest that anorexia nervosa and bulimia nervosa do occur in the Chinese, sparking debate as to whether or not it is the result of Westernization. This project begins with a review of the current literature on eating disorders in Chinese populations and the role of culture as a mediating factor. A psychodynamic conceptualization and the potential role of traumatic experiences are explored in the emergence of pathological eating habits. Research suggests that applying Western models for Chinese subjects with eating disorders may not always be appropriate.


Subject(s)
Feeding and Eating Disorders/ethnology , Adult , China/ethnology , Female , Hong Kong/ethnology , Humans , Young Adult
2.
Clin Pharmacol Ther ; 84(3): 385-92, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18388884

ABSTRACT

A prescription is a health-care program implemented by a physician or other qualified practitioner in the form of instructions that govern the plan of care for an individual patient. Although the algorithmic nature of prescriptions is axiomatic, this insight has not been applied systematically to medication safety. We used software design principles and debugging methods to create a "Patient-oriented Prescription for Analgesia" (POPA), assessed the rate and extent of adoption of POPA by physicians, and conducted a statistical process control clinical trial and a subsidiary cohort analysis to evaluate whether POPA would reduce the rate of severe and fatal opioid-associated adverse drug events (ADEs). We conducted the study in a population of 153,260 hospitalized adults, 50,576 (33%) of whom received parenteral opioids. Hospitalwide, the use of POPA increased to 62% of opioid prescriptions (diffusion half-life = 98 days), while opioid-associated severe/fatal ADEs fell from an initial peak of seven per month to zero per month during the final 6 months (P < 0.0016) of the study. In the nested orthopedics subcohort, the use of POPA increased the practice of recording pain scores (94% vs. 72%, P < 0.00001) and the use of adjuvant analgesics (95% vs. 40%, P < 0.00001) and resulted in fewer opioid-associated severe ADEs than routine patient-controlled analgesia (PCA) (0% vs. 2.7%, number needed to treat (NNT) = 35, P < 0.015). The widespread diffusion of POPA was associated with a substantial hospitalwide decline in opioid-associated severe/fatal ADEs.


Subject(s)
Analgesia, Patient-Controlled/methods , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/adverse effects , Medication Errors/prevention & control , Medication Errors/statistics & numerical data , Pain/drug therapy , Patient-Centered Care/methods , Adult , Aged , Blood Glucose/drug effects , Carbamates/pharmacokinetics , Carbamates/pharmacology , Clinical Trials as Topic , Drug Interactions , Female , Gemfibrozil/pharmacokinetics , Gemfibrozil/pharmacology , Hospital Mortality , Humans , Hypoglycemic Agents/pharmacokinetics , Hypoglycemic Agents/pharmacology , Hypolipidemic Agents/pharmacokinetics , Hypolipidemic Agents/pharmacology , Male , Middle Aged , Multicenter Studies as Topic , Pain/classification , Piperidines/pharmacokinetics , Piperidines/pharmacology , Software
3.
Oncogene ; 19(30): 3352-62, 2000 Jul 13.
Article in English | MEDLINE | ID: mdl-10918592

ABSTRACT

Serum-stimulation of quiescent mouse fibroblasts results in transcriptional activation of tissue factor (TF), the cellular initiator of blood coagulation. This requires the rapid entry of c-Fos into specific AP-1 DNA-binding complexes and can be strongly inhibited by the adenovirus EIA 12S gene product. In this study, we utilized a panel of E1A mutants deficient in cellular protein binding to analyse the molecular basis for EIA inhibition of a minimal, c-Fos-dependent TF promoter/ reporter construct in mouse AKR-2B fibroblasts. Mutations which impaired binding of the retinoblastoma tumor suppressor protein family members pRB, p107, and p130 relieved E1A-mediated inhibition of transcription in response to serum-stimulation or c-Fos overexpression. Inhibition was restricted to the G0 to G1 transition, consistent with the specificity of E1A for hypophosphorylated forms of RB proteins. Although E1A mutants deficient in CBP/p300 binding retained the ability to inhibit TF transcription, deletion of the amino-terminal portion of the CBP/p300 interaction domain was required to permit rescue of TF promoter activity by coexpression of pRB. Moreover, ectopic p107 could effectively substitute for pRB in relieving E1A-mediated repression. In primary mouse embryo fibroblasts, activity of the minimal AP-1-dependent TF promoter was suppressed in Rb(-/-) cells compared to parallel Rb(+/-) and Rb(+/+) transfectants. Ectopic expression of either pRB or p107 markedly enhanced TF promoter activity in Rb(-/-) fibroblasts. Collectively, these data imply that pRB and p107 can cooperate with c-Fos to activate TF gene transcription in fibroblasts and suggest a requirement for another, as yet unidentified, E1A-binding protein.


Subject(s)
Fibroblasts/metabolism , Membrane Glycoproteins/genetics , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Proteins , Receptors, Cell Surface/genetics , Retinoblastoma Protein/metabolism , Thromboplastin/metabolism , Trans-Activators/metabolism , Transcription Factor AP-1/metabolism , Adenovirus E1A Proteins/genetics , Adenovirus E1A Proteins/metabolism , Animals , Binding Sites , Cell Line , Fibroblasts/cytology , Membrane Glycoproteins/metabolism , Mice , Mutagenesis , Nuclear Proteins/genetics , Phosphoproteins/metabolism , Proto-Oncogene Proteins c-fos/genetics , Proto-Oncogene Proteins c-fos/metabolism , Receptors, Cell Surface/metabolism , Retinoblastoma Protein/genetics , Retinoblastoma-Like Protein p107 , Retinoblastoma-Like Protein p130 , Trans-Activators/genetics
4.
J Biol Chem ; 275(20): 15384-91, 2000 May 19.
Article in English | MEDLINE | ID: mdl-10748152

ABSTRACT

Stimulation of quiescent AKR-2B mouse fibroblasts with transforming growth factor beta1 results in uniform conversion to a myofibroblast-like phenotype as judged by a rapid accumulation of smooth muscle alpha-actin mRNA and protein. Because transcriptional regulation of the smooth muscle alpha-actin gene in these cells might be mediated by single-stranded DNA-binding proteins, we have examined the sensitivity of genomic DNA to chemical reagents with specificity for unpaired bases in a region of the promoter previously implicated in Puralpha, Purbeta, and MSY1 binding in vitro (Kelm, R. J., Jr., Cogan, J. G., Elder, P. K., Strauch, A. R., and Getz, M. J. (1999) J. Biol. Chem. 274, 14238-14245). Our data reveal specific differences between purified DNA treated in vitro and nucleoprotein complexes treated in living cells. Although some differences were observed in quiescent cells, treatment with transforming growth factor beta1 resulted in the development of additional sensitivity within 1 h. This enhancement was most pronounced in bases immediately upstream of an MCAT enhancer element-containing polypurine-polypyrimidine tract. A TATA-proximal element of similar base distribution showed no such hyperreactivities. These results suggest that activation of the endogenous smooth muscle alpha-actin gene during myofibroblast conversion is accompanied by specific structural changes in the promoter that are consistent with a decline in single-stranded DNA repressor protein binding.


Subject(s)
Actins/genetics , DNA, Single-Stranded/drug effects , Fibroblasts/drug effects , Muscle, Smooth, Vascular/metabolism , Promoter Regions, Genetic , Transforming Growth Factor beta/pharmacology , Animals , Base Sequence , Becaplermin , Cell Differentiation/drug effects , Enhancer Elements, Genetic , Epidermal Growth Factor/pharmacology , Fibroblasts/cytology , Fibroblasts/metabolism , Insulin/pharmacology , Kinetics , Mice , Molecular Sequence Data , Platelet-Derived Growth Factor/pharmacology , Proto-Oncogene Proteins c-sis , TATA Box
5.
J Biol Chem ; 274(53): 38268-75, 1999 Dec 31.
Article in English | MEDLINE | ID: mdl-10608902

ABSTRACT

Amino acids 44-53 of mouse vascular smooth muscle alpha-actin are encoded by a region of exon 3 that bears structural similarity to an essential MCAT enhancer element in the 5' promoter of the gene. The single-stranded DNA-binding proteins, Puralpha, Purbeta, and MSY1, interact with each other and with opposite strands of the enhancer to repress transcription in fibroblasts (Sun, S., Stoflet, E. S., Cogan, J. G., Strauch, A. R., and Getz, M. J. (1995) Mol. Cell. Biol. 15, 2429-2436; Kelm, R. J., Jr., Cogan, J. G., Elder, P. K., Strauch, A. R., and Getz, M. J. (1999) J. Biol. Chem. 274, 14238-14245). In this study, we employed both recombinant and fibroblast-derived proteins to demonstrate that all three proteins specifically interact with the mRNA counterpart of the exon 3 sequence in cell-free binding assays. When placed in the 5'-untranslated region of a reporter mRNA, the exon 3-derived sequence suppressed mRNA translation in transfected fibroblasts. Translational efficiency was restored by mutations that impaired mRNA binding of Puralpha, Purbeta, and MSY1, implying that these proteins can also participate in messenger ribonucleoprotein formation in living cells. Additionally, primary structure determinants required for interaction of Purbeta with single-stranded DNA, mRNA, and protein ligands were mapped by deletion mutagenesis. These experiments reveal highly specific protein-mRNA interactions that are potentially important in regulating expression of the vascular smooth muscle alpha-actin gene in fibroblasts.


Subject(s)
Actins/genetics , DNA, Single-Stranded/metabolism , DNA-Binding Proteins/metabolism , Exons , Muscle, Smooth, Vascular/metabolism , RNA, Messenger/metabolism , Amino Acid Sequence , Animals , Base Sequence , Blotting, Northern , Blotting, Western , Cloning, Molecular , DNA Primers , DNA, Complementary , DNA-Binding Proteins/chemistry , Genes, Reporter , Mice , Molecular Sequence Data , RNA, Messenger/genetics , Sequence Homology, Amino Acid
6.
J Biol Chem ; 274(20): 14238-45, 1999 May 14.
Article in English | MEDLINE | ID: mdl-10318844

ABSTRACT

Transcriptional activity of the mouse vascular smooth muscle alpha-actin gene in fibroblasts is regulated, in part, by a 30-base pair asymmetric polypurine-polypyrimidine tract containing an essential MCAT enhancer motif. The double-stranded form of this sequence serves as a binding site for a transcription enhancer factor 1-related protein while the separated single strands interact with two distinct DNA binding activities termed VACssBF1 and 2 (Cogan, J. G., Sun, S., Stoflet, E. S., Schmidt, L. J., Getz, M. J., and Strauch, A. R. (1995) J. Biol. Chem. 270, 11310-11321; Sun, S., Stoflet, E. S., Cogan, J. G., Strauch, A. R., and Getz, M. J. (1995) Mol. Cell. Biol. 15, 2429-2936). VACssBF2 has been recently cloned and shown to consist of two closely related proteins, Puralpha and Purbeta (Kelm, R. J., Elder, P. K., Strauch, A. R., and Getz, M. J. (1997) J. Biol. Chem. 272, 26727-26733). In this study, we demonstrate that Puralpha and Purbeta interact with each other via highly specific protein-protein interactions and bind to the purine-rich strand of the MCAT enhancer in the form of both homo- and heteromeric complexes. Moreover, both Pur proteins interact with MSY1, a VACssBF1-like protein cloned by virtue of its affinity for the pyrimidine-rich strand of the enhancer. Interactions between Puralpha, Purbeta, and MSY1 do not require the participation of DNA. Combinatorial interactions between these three single-stranded DNA-binding proteins may be important in regulating activity of the smooth muscle alpha-actin MCAT enhancer in fibroblasts.


Subject(s)
Actins/genetics , DNA, Single-Stranded/metabolism , DNA-Binding Proteins/metabolism , Enhancer Elements, Genetic , Muscle, Smooth, Vascular/metabolism , Promoter Regions, Genetic , Amino Acid Sequence , Animals , Antibodies/chemistry , Cyclic AMP Response Element-Binding Protein/immunology , Cyclic AMP Response Element-Binding Protein/metabolism , DNA-Binding Proteins/immunology , Enzyme-Linked Immunosorbent Assay , Mice , Molecular Sequence Data , Nerve Tissue Proteins , Protein Binding , Transcription Factors , Transcriptional Activation
7.
J Biol Chem ; 272(42): 26727-33, 1997 Oct 17.
Article in English | MEDLINE | ID: mdl-9334258

ABSTRACT

Transcriptional repression of the mouse vascular smooth muscle alpha-actin gene in fibroblasts and myoblasts is mediated, in part, by the interaction of two single-stranded DNA binding activities with opposite strands of an essential transcription enhancer factor-1 recognition element (Sun, S., Stoflet, E. S., Cogan, J. G., Strauch, A. R., and Getz, M. J. (1995) Mol. Cell. Biol. 15, 2429-2436). One of these activities, previously designated vascular actin single-stranded DNA-binding factor 2 includes two distinct polypeptides (p44 and p46) which specifically interact with the purine-rich strand of both the enhancer and a related element in a protein coding exon of the gene (Kelm, R. J., Jr., Sun, S., Strauch, A. R., and Getz, M. J. (1996) J. Biol. Chem. 271, 24278-24285). Expression screening of a mouse lung cDNA library with a vascular actin single-stranded DNA-binding factor 2 recognition element has now resulted in the isolation of two distinct cDNA clones that encode p46 and p44. One of these proteins is identical to Puralpha, a retinoblastoma-binding protein previously implicated in both transcriptional activation and DNA replication. The other is a related family member, presumably Purbeta. Comparative band shift and Southwestern blot analyses conducted with cellular p46, p44, and cloned Pur proteins synthesized in vitro and in vivo, establish identity of p46 with Puralpha and p44 with Purbeta. This study implicates Puralpha and/or Purbeta in the control of vascular smooth muscle alpha-actin gene transcription.


Subject(s)
Cyclic AMP Response Element-Binding Protein , DNA-Binding Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , DNA, Complementary , Electrophoresis, Polyacrylamide Gel , Genes, myc , Humans , Mice , Molecular Sequence Data , Nerve Tissue Proteins , Sequence Homology, Amino Acid , Transcription Factors
9.
Oncogene ; 14(14): 1679-85, 1997 Apr 10.
Article in English | MEDLINE | ID: mdl-9135069

ABSTRACT

Stimulation of quiescent mouse fibroblasts with TGF-beta1 and certain other growth factors result in cooperative activation of tissue factor (TF) gene transcription, an event accompanied by the rapid entry of c-Fos into specific AP-1 DNA-binding complexes (Felts et al. (1995) Biochemistry 34, 12355-12362). Here, we demonstrate that the ability of TGF-beta1 to synergistically activate TF transcription in serum-stimulated fibroblasts is dependent upon both c-Fos and a promoter-specific factor with functional properties characteristic of transcriptional coactivators. Inhibition of TF promoter activity by an adenovirus E1A mutant deleted in an essential CREB binding protein (CBP) interaction domain suggests that this factor is distinct from the CBP/p300 family of transcriptional coactivators. Importantly, the ability of this factor to mediate molecular interactions with c-Fos required for transcriptional synergism is directly linked to TGF-beta1 signaling. These data suggest a model in which a component of the TF basal transcription complex functions to integrate multiple signaling pathways required for full transcriptional activation of TF in fibroblasts.


Subject(s)
Adenovirus E1A Proteins/physiology , Proto-Oncogene Proteins c-fos/physiology , Trans-Activators , Transforming Growth Factor beta/physiology , Animals , CREB-Binding Protein , Cells, Cultured , Cyclic AMP Response Element-Binding Protein/metabolism , DNA-Binding Proteins/metabolism , Drug Synergism , Gene Expression Regulation , Mice , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Signal Transduction , Thromboplastin/genetics , Transcription Factors/metabolism
11.
Cancer Res ; 56(21): 5063-70, 1996 Nov 01.
Article in English | MEDLINE | ID: mdl-8895765

ABSTRACT

Tissue factor (TF), the cellular initiator of the protease blood coagulation cascade, has been shown to be expressed in a variety of solid tumors, particularly those of epithelial origin. However, the mechanisms that mediate TF expression in tumors, as well as the clinical implications of this expression, remain largely unknown. In this study, we examined the cytological distribution of TF in normal human breast tissue and breast carcinomas. Epithelial cells exhibited TF immunoreactivity with little obvious correlation with malignant progression from in situ lesions to invasive cancer. However, there was a strong correlation between progression to invasive cancer and the expression of TF antigen in cellular components of the stroma. TF-positive cells were particularly abundant in close proximity to infiltrating tumor cells and included both macrophages and myofibroblasts, as determined by double-immunofluorescent staining for TF and cell type-specific marker proteins. Double-immunofluorescent staining for TF and transforming growth factor beta (TGF-beta) revealed TGF-beta immunoreactivity both in tumor cells and in the extracellular matrix surrounding TF-positive stromal cells. To test the role of carcinoma cell-derived growth factors in the regulation of stromal cell TF activity, we examined the ability of conditioned media (CM) from breast carcinoma cell lines to stimulate TF activity in myofibroblast-like cells in vitro. Extracts from myofibroblasts exposed to CM displayed strong TF procoagulant activity. However, extracts from cells exposed to unconditioned media or CM pretreated with anti-TGF-beta antibodies did not. The induction of TF activity was also observed upon treatment of indicator cells with recombinant TGF-beta isoforms. Collectively, these data indicate that the recruitment and/or activation of TF-expressing stromal cells is an early event in progression to invasive breast cancer and likely occurs, in part, as a paracrine response to tumor cell-derived members of the TGF-beta family of growth factors.


Subject(s)
Breast Neoplasms/chemistry , Thromboplastin/analysis , Transforming Growth Factor beta/physiology , Actins/analysis , Animals , Breast/chemistry , Breast Neoplasms/pathology , Female , Humans , Mice , Mice, Inbred AKR , Thromboplastin/physiology , Transforming Growth Factor beta/analysis , Tumor Cells, Cultured
12.
J Biol Chem ; 271(39): 24278-85, 1996 Sep 27.
Article in English | MEDLINE | ID: mdl-8798674

ABSTRACT

Transcriptional repression of the murine vascular smooth muscle alpha-actin gene in fibroblasts results from the interaction of two sequence-specific single-stranded DNA binding activities (VACssBF1 and VACssBF2) with opposite strands of an essential transcriptional enhancer factor-1 (TEF-1) element (Sun, S., Stoflet, E. S., Cogan, J. G., Strauch, A. R., and Getz, M. J. (1995) Mol. Cell. Biol. 15, 2429-2436). Here, we identify a sequence element located within a protein-coding exon of the gene that bears structural similarity with the TEF-1 enhancer. This includes a 30-base pair region of purine-pyrimidine asymmetry encompassing a perfect 6-base pair GGAATG TEF-1 recognition motif. Unlike the enhancer, however, the exon sequence exhibits no TEF-1 binding activity nor does the pyrimidine-rich strand bind VACssBF1. However, VACssBF2 interacts equally well with the purine-rich strand of both the enhancer and the exon sequence. To test the ability of VACssBF2 to independently repress transcription, the exon sequence was placed upstream of a deletionally activated promoter containing an intact TEF-1 binding site. The exon sequence repressed promoter activity, whereas a mutant deficient in VACssBF2 binding did not. Moreover, VACssBF2 similarly repressed activator protein-1-dependent transcription of a heterologous tissue factor promoter. These results suggest that VACssBF2 possesses an intrinsic ability to disrupt enhancer function independently of the enhancer-binding proteins involved.


Subject(s)
Actins/genetics , DNA-Binding Proteins/metabolism , Enhancer Elements, Genetic , Nuclear Proteins , Repressor Proteins/genetics , Repressor Proteins/metabolism , Transcription Factors/metabolism , 3T3 Cells , Animals , Cell Line , DNA, Single-Stranded/metabolism , Exons , Gene Expression Regulation , Mice , Molecular Weight , Muscle, Smooth, Vascular , Promoter Regions, Genetic , TEA Domain Transcription Factors , Transcription, Genetic
13.
Biochemistry ; 34(38): 12355-62, 1995 Sep 26.
Article in English | MEDLINE | ID: mdl-7547979

ABSTRACT

Serum stimulation of quiescent mouse fibroblasts results in transcriptional activation of tissue factor (TF), the cellular initiator of the protease cascade leading to blood coagulation. In this study, we demonstrate that two AP-1 DNA-binding elements located 200-220 bp upstream of the transcription start site are both necessary and sufficient to confer serum inducibility to the TF gene promoter in fibroblasts. Analysis of AP-1 DNA-binding complexes indicates that the predominant form of AP-1 activity in quiescent cells consists of an unidentified Fos-related protein and JunD. While c-Fos is notably absent from these preexisting complexes, serum stimulation results in the rapid entry of c-Fos into the TF AP-1 DNA-binding complexes. A similar induction of c-Fos DNA-binding activity occurs in cells treated with recombinant growth factors such as platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF). Importantly, overexpression of JunD and c-Fos abrogates the requirement for serum in the stimulation of TF promoter activity in fibroblasts. Together, these data indicate that the entry of c-Fos into heterodimeric AP-1 DNA-binding complexes with JunD is a key event underlying serum-stimulated transcription of the TF gene in fibroblasts.


Subject(s)
Promoter Regions, Genetic , Proto-Oncogene Proteins c-fos/metabolism , Thromboplastin/genetics , Transcription Factor AP-1/metabolism , Transcription, Genetic , Animals , Base Sequence , Cells, Cultured , Culture Media, Serum-Free , Cycloheximide/pharmacology , Drug Synergism , Fibroblasts , Gene Expression Regulation , Growth Substances/pharmacology , Mice , Models, Genetic , Molecular Sequence Data , Mutagenesis, Site-Directed , NF-kappa B/metabolism , Protein Binding , Sequence Deletion , Thromboplastin/biosynthesis
14.
J Biol Chem ; 270(19): 11310-21, 1995 May 12.
Article in English | MEDLINE | ID: mdl-7744768

ABSTRACT

Transcriptional activity of the mouse vascular smooth muscle (VSM) alpha-actin promoter was governed by both cell type and developmental stage-specific mechanisms. A purine-rich motif (PrM) located as -181 to -176 in the promoter was absolutely required for activation in mouse AKR-2B embryonic fibroblasts and partially contributed to activation in undifferentiated mouse BC3H1 myoblasts. Transcriptional enhancer factor 1 recognized the PrM and cooperated with other promoter-binding proteins to regulate serum growth factor-dependent transcription in both myoblasts and fibroblasts. Two distinct protein factors (VAC-ssBF1 and VAC-ssBF2) also were identified that bound sequence-specifically to single-stranded oligonucleotide probes that spanned both the PrM and a closely positioned negative regulatory element. VAC-ssBF1 and BF2 binding activity was detected in undifferentiated myoblasts, embryonic fibroblasts, and several smooth muscle tissues in the mouse and human. A myoblast-specific protein (VAC-RF1) also was detected that bound double-stranded probes containing a CArG-like sequence that previously was shown to impart strong, cell type specific repression. The binding activity of transcription enhancer factor 1, VAC-RF1, and VAC-ssBF1 was significantly diminished when confluent BC3H1 myoblasts differentiated into myocytes and expressed VSM alpha-actin mRNA after exposure to serum-free medium. The results indicated that cell type-specific control of the VSM alpha-actin gene promoter required the participation of multiple DNA-binding proteins, including two that were enriched in smooth muscle and had preferential affinity for single-stranded DNA.


Subject(s)
Actins/biosynthesis , DNA-Binding Proteins/metabolism , Gene Expression , Muscles/metabolism , Promoter Regions, Genetic , Transcription, Genetic , Actins/genetics , Animals , Base Sequence , Cell Differentiation , Cell Line , Chloramphenicol O-Acetyltransferase/biosynthesis , DNA-Binding Proteins/isolation & purification , Embryo, Mammalian , Fibroblasts/metabolism , Mice , Mice, Inbred AKR , Molecular Sequence Data , Muscles/cytology , Nuclear Proteins/isolation & purification , Nuclear Proteins/metabolism , Oligonucleotide Probes , TATA Box , Transfection
15.
Mol Cell Biol ; 15(5): 2429-36, 1995 May.
Article in English | MEDLINE | ID: mdl-7739527

ABSTRACT

Transcriptional activation and repression of the vascular smooth muscle (VSM) alpha-actin gene in myoblasts and fibroblasts is mediated, in part, by positive and negative elements contained within an approximately 30-bp polypurine-polypyrimidine tract. This region contains binding sites for an essential transcription-activating protein, identified as transcriptional enhancer factor I (TEF-1), and two tissue-restrictive, sequence-specific, single-stranded-DNA-binding activities termed VACssBF1 and VACssBF2. TEF-1 has no detectable single-stranded-DNA-binding activity, while VACssBF1 and VACssBF2 have little, if any, affinity for double-stranded DNA. Site-specific mutagenesis experiments demonstrate that the determinants of VACssBF1 and VACssBF2 binding lie on opposite strands of the DNA helix and include the TEF-1 recognition sequence. Functional analysis of this region reveals that the CCAAT box-binding protein nuclear factor Y (NF-Y) can substitute for TEF-1 in activating VSM alpha-actin transcription but that the TEF-1-binding site is essential for the maintenance of full transcriptional repression. Importantly, replacement of the TEF-1-binding site with that for NF-Y diminishes the ability of VACssBF1 and VACssBF2 to bind to separated single strands. Additional activating mutations have been identified which lie outside of the TEF-1-binding site but which also impair single-stranded-DNA-binding activity. These data support a model in which VACssBF1 and VACssBF2 function as repressors of VSM alpha-actin transcription by stabilizing a local single-stranded-DNA conformation, thus precluding double-stranded-DNA binding by the essential transcriptional activator TEF-1.


Subject(s)
Actins/genetics , Muscle, Smooth, Vascular/metabolism , Animals , Base Sequence , Binding Sites/genetics , Cell Line , Conserved Sequence , DNA, Single-Stranded/genetics , DNA, Single-Stranded/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Down-Regulation , Enhancer Elements, Genetic , Fibroblasts/metabolism , Mice , Molecular Sequence Data , Mutation , Promoter Regions, Genetic , TEA Domain Transcription Factors , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptional Activation
16.
Mol Cell Biol ; 14(11): 7527-34, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7935468

ABSTRACT

The intrinsic tyrosine kinase activity of the epidermal growth factor receptor (EGFR) has been shown to be responsible for many of the pleiotropic intracellular effects resulting from ligand stimulation [W.S. Chen, C.S. Lazar, M. Poenie, R.Y. Tsien, G.N. Gill, and M.G. Rosenfeld, Nature (London) 328:820-823, 1987; A.M. Honegger, D. Szapary, A. Schmidt, R. Lyall, E. Van Obberghen, T.J. Dull, A. Ulrich, and J. Schlessinger, Mol. Cell. Biol. 7:4568-4571, 1987]. Recently, however, it has been shown that addition of ligand to cells expressing kinase-defective EGFR mutants can result in the phosphorylation of mitogen-activated protein kinase (R. Campos-González and J.R. Glenney, Jr., J. Biol. Chem. 267:14535-14538, 1992; E. Selva, D.L. Raden, and R.J. Davis, J. Biol. Chem. 268:2250-2254, 1993), as well as stimulation of DNA synthesis (K.J. Coker, J.V. Staros, and C.A. Guyer, Proc. Natl. Acad. Sci. USA 91:6967-6971, 1994). Moreover, mitogen-activated protein kinase has been shown to phosphorylate the transcription factor p62TCF in vitro, leading to enhanced ternary complex formation between p62TCF, p67SRF, and the c-fos serum response element (SRE) [H. Gille, A.D. Sharrocks, and P.E. Shaw, Nature (London) 358:414-417, 1992]. On the basis of these observations, we have investigated the possibility that the intrinsic tyrosine kinase activity of the EGFR may not be necessary for transcriptional activation mediated via p62TCF. Here, we demonstrate that a kinase-defective EGFR mutant can signal ligand-induced expression of c-fos protein and that a significant component of this induction appears to be mediated at the transcriptional level. Investigation of transcriptional activation mediated by the c-fos SRE shows that this response is impaired by mutations in the SRE which eliminate binding of p62(TCF). These data indicate that information inherent in the structure of the EGFR can be accessed by ligand stimulation independent of the receptor's catalytic kinase function.


Subject(s)
ErbB Receptors/metabolism , Genes, fos , Mitogen-Activated Protein Kinases , Animals , Base Sequence , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Cell Line , DNA/genetics , ErbB Receptors/genetics , Gene Expression Regulation , Mice , Mitogen-Activated Protein Kinase 3 , Molecular Sequence Data , Mutation , Protein-Tyrosine Kinases/genetics , Protein-Tyrosine Kinases/metabolism , Signal Transduction , Transcriptional Activation , Transforming Growth Factor alpha/pharmacology
17.
J Prosthet Dent ; 71(6): 631-9, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8040829

ABSTRACT

This article discusses a metal full-arch interocclusal impression tray. It uses a separation insert that extends into a split handle. Portions of the tray may be used to record sections of an arch singly or in combination from quadrant to full arch. A combination of different materials may be used, selected for low-cost properties that work compatibly side-by-side and/or back-to-back. The tray can be modified by the addition of a mounting stud to the tray handle, which permits linking it to a face-bow to facilitate axis mounting.


Subject(s)
Dental Impression Technique/instrumentation , Costs and Cost Analysis , Dental Impression Technique/economics , Dental Materials , Equipment Design , Humans , Stainless Steel
18.
Mol Biol Cell ; 3(10): 1073-83, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1421567

ABSTRACT

Treatment of AKR-2B mouse fibroblasts with serum growth factors or inhibitors of protein synthesis, such as cycloheximide, results in a stimulation of cytoskeletal beta-actin transcription but has no effect on transcription of muscle-specific isotypes, such as the vascular smooth muscle (VSM) alpha-actin gene. Deletion mapping and site-specific mutagenesis studies demonstrated that a single "CArG" element of the general form CC(A/T)6GG was necessary and possibly sufficient to impart serum and cycloheximide-inducibility to the beta-actin promoter. Although the VSM alpha-actin promoter exhibits at least three similar sequence elements, it remained refractory to serum and cycloheximide induction. However, deletion of a 33 base pair sequence between -191 and -224 relative to the transcription start site resulted in the transcriptional activation of this muscle-specific promoter in rapidly growing or serum-stimulated fibroblasts. Although the activity of this truncated promoter was potentiated by cycloheximide in a manner indistinguishable from that of the beta-actin promoter, this was dependent on a more complex array of interacting elements. These included at least one CArG box and a putative upstream activating element closely associated with the -191 to -224 inhibitory sequences. These results demonstrate that the expression of a muscle-specific actin gene in fibroblasts is suppressed by a cis-acting negative control element and that in the absence of this element, the promoter is responsive to growth factor-induced signal transduction pathways.


Subject(s)
Actins/genetics , Muscle, Smooth, Vascular/metabolism , Animals , Base Sequence , Cell Line , Chromosome Mapping , Cycloheximide/pharmacology , DNA/genetics , Enhancer Elements, Genetic , Fibroblasts/metabolism , Gene Deletion , Gene Expression Regulation , Mice , Molecular Sequence Data , Mutagenesis, Site-Directed , Promoter Regions, Genetic , Transcription, Genetic/drug effects
19.
J Biol Chem ; 267(17): 11995-2003, 1992 Jun 15.
Article in English | MEDLINE | ID: mdl-1601869

ABSTRACT

Segments of the 5'-flanking region of the mouse vascular smooth muscle alpha-actin gene were assayed for promoter activity in transfected mouse BC3H1 myogenic cells and AKR-2B embryonic fibroblasts. The region between -150 and -191 that functions as a positive transcriptional element in myogenic and fibroblastic cells contains a mammalian-specific inverted CC(A/T)6GG-type consensus sequence. Expression was restricted to fully differentiated myogenic cells when an additional sequence spanning -191 to -224 was included in reporter gene constructs. This 33-base pair (bp) negative regulatory element is 70% conserved between the mouse and human genes and contains a 10-bp motif at its 3' end that only partially resembles a CC(A/T)6GG element. Retention of a GGGA motif at the 3' boundary of the 33-bp region is sufficient to maintain full transcriptional repression in fibroblasts and is partly responsible for repression in undifferentiated myoblasts. Complete muscle tissue-restrictive expression requires an additional 8 bp from the CC(A/T)6GG-like element immediately 5' to the GGGA motif, since replacement of this region with an unrelated 10-bp sequence completely eliminated restrictive transcriptional behavior in undifferentiated myoblasts. The distal portion of the 5'-flanking region between -224 and -1074 contains six E-box motifs (CANNTG) and mediates high level transcription only in postconfluent BC3H1 myoblasts. Analysis of reporter gene constructs including either the proximal E-box at -240 or all six E-boxes indicate that the five distal E-boxes are not required for high level transcription. A 724-bp segment of the 5'-flanking region consisting of the proximal E-box flanked upstream by a mammalian-specific 352-bp region was sufficient for maximal transcriptional activation in postconfluent BC3H1 myoblasts. Deletion of the 352-bp region restricts the early transcriptional response to high cell density in temporal studies of promoter activity during BC3H1 myogenic cell differentiation.


Subject(s)
Actins/genetics , Gene Expression Regulation , Muscle, Smooth, Vascular/metabolism , Animals , Base Sequence , Cell Differentiation , Chloramphenicol O-Acetyltransferase/genetics , DNA , Fibroblasts/metabolism , Growth Hormone/genetics , Growth Hormone/metabolism , Mice , Molecular Sequence Data , Muscle, Smooth, Vascular/cytology , Plasmids , Promoter Regions, Genetic , Regulatory Sequences, Nucleic Acid , Transcription, Genetic , Transfection
20.
J Dev Behav Pediatr ; 12(4): 217-22, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1719033

ABSTRACT

The concurrent validity and reliability of the Minnesota Child Development Inventory (MCDI) was assessed by comparing the MCDI general development index score, and each of the seven subscale scores, with the mental and psychomotor age equivalents achieved on the Bayley Scales of Infant Development. In addition, the co-positivity, co-negativity, positive and negative predictive values of the MCDI in identifying infants with a mental development index (MDI), or psychomotor development index (PDI) of greater than 2 SD below the mean were assessed. Subjects were 101 infants (8 to 19 months old) who were seen at a neonatal developmental follow-up clinic after discharge from the neonatal intensive care unit. Correlations were obtained for the entire sample as well as for the two chronological age groups (i.e., 8 to 10 months and 17 to 19 months) within the sample. A strong correlation between the MCDI scales and the Bayley Mental and Psychomotor Scales was documented for the entire population as well as for the individual age groups. The overall validity of the MCDI in identifying infants with a MDI or PDI of greater than 2 SD below the mean was limited due to relatively poor co-positivity and positive predictive value. Although the MCDI may yield consistent information about the development of an infant's skills, this research suggests the MCDI has limited capacity to discern infants having delayed development.


Subject(s)
Aptitude , Brain Damage, Chronic/diagnosis , Child Development , Infant, Premature, Diseases/diagnosis , Intelligence , Neurologic Examination/statistics & numerical data , Psychomotor Performance , Brain Damage, Chronic/psychology , Child, Preschool , Developmental Disabilities/diagnosis , Developmental Disabilities/psychology , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Infant, Premature, Diseases/psychology , Language Development Disorders/diagnosis , Language Development Disorders/psychology , Male , Psychometrics , Risk Factors , Social Adjustment
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