Open Access. Powered by Scholars. Published by Universities.®

Medical Specialties Commons™

Open Access. Powered by Scholars. Published by Universities.®

Animals

Discipline
Institution
Publication Year
Publication
Publication Type
File Type

Articles 4231 - 4260 of 4262

Full-Text Articles in Medical Specialties

Phosphorylation Of Elongation Factor 1 And Ribosomal Protein S6 By Multipotential S6 Kinase And Insulin Stimulation Of Translational Elongation, Y W Chang, J A Traugh Nov 1997

Phosphorylation Of Elongation Factor 1 And Ribosomal Protein S6 By Multipotential S6 Kinase And Insulin Stimulation Of Translational Elongation, Y W Chang, J A Traugh

Faculty, Staff and Student Publications

Stimulation of protein synthesis in response to insulin is concomitant with increased phosphorylation of initiation factors 4B and 4G and ribosomal protein S6 (Morley, S. J., and Traugh, J. A. (1993) Biochimie 75, 985-989) and is due at least in part to multipotential S6 kinase. When elongation factor 1 (EF-1) from rabbit reticulocytes was examined as substrate for multipotential S6 kinase, up to 1 mol/mol of phosphate was incorporated into the alpha, beta, and delta subunits. Phosphorylation of EF-1 resulted in a 2-2. 6-fold stimulation of EF-1 activity, as measured by poly(U)-directed polyphenylalanine synthesis. The rate of elongation was also …

Go to article

Detection And Characterization Of Sp1 Binding Activity In Human Chondrocytes And Its Alterations During Chondrocyte Dedifferentiation., Rita M. Dharmavaram, Gang Liu, Sheryl D. Mowers, Sergio A. Jimenez Oct 1997

Detection And Characterization Of Sp1 Binding Activity In Human Chondrocytes And Its Alterations During Chondrocyte Dedifferentiation., Rita M. Dharmavaram, Gang Liu, Sheryl D. Mowers, Sergio A. Jimenez

Department of Medicine Faculty Papers

We have detected DNA binding activity for a synthetic oligonucleotide containing an Sp1 consensus sequence in nuclear extracts from human chondrocytes. Changes in the levels of Sp1 oligonucleotide binding activity were examined in nuclear extracts from freshly isolated human chondrocytes, from chondrocytes that had been cultured under conditions that allowed the maintenance of a chondrocyte-specific phenotype on plastic dishes coated with the hydrogel poly(2-hydroxyethyl methacrylate), and from chondrocytes induced to dedifferentiate into fibroblast-like cells by passage in monolayer culture on plastic substrata. It was observed that Sp1 binding was 2-3-fold greater in nuclear extracts from dedifferentiated chondrocytes than in nuclear …

Go to article

Intrinsic And Extrinsic Control Of Hemopoietic Stem Cell Numbers: Mapping Of A Stem Cell Gene, Gerald De Haan, Gary Van Zant Aug 1997

Intrinsic And Extrinsic Control Of Hemopoietic Stem Cell Numbers: Mapping Of A Stem Cell Gene, Gerald De Haan, Gary Van Zant

Markey Cancer Center Faculty Publications

We evaluated in vivo interactions between extrinsic (growth factor induced) and intrinsic (genetically determined) effectors of mouse primitive hemopoietic stem cell proliferation and numbers. Accordingly, stem cell frequency and cell cycle kinetics were assessed in eight strains of inbred mice using the cobblestone area–forming cell (CAFC) assay. A strong inverse correlation was observed between mouse lifespan and the number of autonomously cycling progenitors (CAFC day 7) in the femur. The population size of primitive stem cells (CAFC day 35) varied widely (up to sevenfold) among strains, unlike total CAFC day 7 numbers (cycling and quiescent), which were similar. Administration of …

Go to article

Bovine Oviductal And Embryonic Insulin-Like Growth Factor Binding Proteins: Possible Regulators Of "Embryotrophic" Insulin-Like Growth Factor Circuits., Q A Winger, P De Los Rios, V K Han, D T Armstrong, D J Hill, A J Watson Jun 1997

Bovine Oviductal And Embryonic Insulin-Like Growth Factor Binding Proteins: Possible Regulators Of "Embryotrophic" Insulin-Like Growth Factor Circuits., Q A Winger, P De Los Rios, V K Han, D T Armstrong, D J Hill, A J Watson

Obstetrics & Gynaecology Publications

Bovine oviductal monolayer and vesicle primary cultures express insulin-like growth factor (IGF)-I and -II mRNAs and polypeptides. Early bovine embryos also express IGF-I, IGF-II, IGF-I receptor, IGF-II receptor, and insulin receptor mRNAs. This study reports the expression of IGF binding protein (IGFBP) mRNAs and polypeptides in bovine oviduct primary cultures and IGFBP mRNAs in preattachment embryos. Release of immunoreactive IGF-I and IGF-II by oviduct cultures and bovine blastocysts was also determined. IGFBP-2, -3, -4, and -5 transcripts were observed in oviduct primary cultures throughout an 8-day interval. IGFBP-1 and -6 mRNAs were consistently not detected in the oviduct. Messenger RNAs …

Go to article

Neuroprotective Action Of Cycloheximide Involves Induction Of Bcl-2 And Antioxidant Pathways, Katsutoshi Furukawa, Steven Estus, Weiming Fu, Robert J. Mark, Mark P. Mattson Mar 1997

Neuroprotective Action Of Cycloheximide Involves Induction Of Bcl-2 And Antioxidant Pathways, Katsutoshi Furukawa, Steven Estus, Weiming Fu, Robert J. Mark, Mark P. Mattson

Sanders-Brown Center on Aging Faculty Publications

The ability of the protein synthesis inhibitor cycloheximide (CHX) to prevent neuronal death in different paradigms has been interpreted to indicate that the cell death process requires synthesis of “killer” proteins. On the other hand, data indicate that neurotrophic factors protect neurons in the same death paradigms by inducing expression of neuroprotective gene products. We now provide evidence that in embryonic rat hippocampal cell cultures, CHX protects neurons against oxidative insults by a mechanism involving induction of neuroprotective gene products including the antiapoptotic gene bcl-2 and antioxidant enzymes. Neuronal survival after exposure to glutamate, FeSO4, and amyloid β-peptide …

Go to article

Loss Of Dcc Expression And Glioma Progression., M Reyes-Mugica, K Rieger-Christ, H Ohgaki, B C Ekstrand, M Helie, G Kleinman, Alan M. Yahanda Md, Facs, E R Fearon, P Kleihues, M A Reale Feb 1997

Loss Of Dcc Expression And Glioma Progression., M Reyes-Mugica, K Rieger-Christ, H Ohgaki, B C Ekstrand, M Helie, G Kleinman, Alan M. Yahanda Md, Facs, E R Fearon, P Kleihues, M A Reale

PCI Publications and Projects

The deleted in colorectal cancer (DCC) gene, a candidate tumor suppressor gene on chromosome 18q21, encodes a neural cell adhesion molecule family protein that is most highly expressed in the nervous system. To address the hypothesis that DCC may play a role in glioma development and/or progression, we examined DCC expression by immunohistochemistry in 57 resected human astrocytic tumors. Overall, low-grade astrocytomas were predominantly DCC positive (15 of 16, or 94%), whereas high-grade tumors significantly less often expressed the DCC protein (27 of 41, or 66%; P = 0.03). We were able to directly assess the relationship between DCC expression …

Go to article

Removal Of Extracellular Chloride Suppresses Transmitter Release From Photoreceptor Terminals In The Mudpuppy Retina., Wallace B. Thoreson, R . F. Miller May 1996

Removal Of Extracellular Chloride Suppresses Transmitter Release From Photoreceptor Terminals In The Mudpuppy Retina., Wallace B. Thoreson, R . F. Miller

Journal Articles: Ophthalmology

Removal of extracellular Cl- has been shown to suppress light-evoked voltage responses of ON bipolar and horizontal cells, but not photoreceptors or OFF bipolar cells, in the amphibian retina. A substantial amount of experimental evidence has demonstrated that the photoreceptor transmitter, L-glutamate, activates cation, not Cl-, channels in these cells. The mechanism for Cl-free effects was therefore reexamined in a superfused retinal slice preparation from the mudpuppy (Necturus maculosus) using whole-cell voltage and current clamp techniques. In a Cl-free medium, light-evoked currents were maintained in rod and cone photoreceptors but suppressed in horizontal, ON bipolar, and OFF bipolar cells. Changes …

Go to article

Prefabrication Of A Secondary Tram Flap., Geoffrey G. Hallock Md May 1996

Prefabrication Of A Secondary Tram Flap., Geoffrey G. Hallock Md

Department of Surgery

A secondary TRAM flap was prefabricated in a rat model using the rectus muscle. The right rectus muscle was elevated as an inferiorly pedicled muscle flap in one experimental group (n = 6) and as a superiorly pedicled muscle flap in a second group (n = 5) and then sandwiched between a silicone sheet and the abdominal skin. Two weeks later, the abdominal skin and attached rectus muscle were elevated over the silicone sheet as a secondary TRAM flap. The surviving skin paddle areas of these prefabricated TRAM flaps were compared with superiorly (n = 7) and inferiorly (n = …

Go to article

Analysis Of The Effects Of Overexpression Of Metallothionein-I In Transgenic Mice On The Reproductive Toxicology Of Cadmium., T Dalton, Kai Fu, G C Enders, R D Palmiter, G K Andrews Jan 1996

Analysis Of The Effects Of Overexpression Of Metallothionein-I In Transgenic Mice On The Reproductive Toxicology Of Cadmium., T Dalton, Kai Fu, G C Enders, R D Palmiter, G K Andrews

Journal Articles: Pathology and Microbiology

Exposure to low levels of cadmium reduces fertility. In male mice spermatogenesis is highly sensitive to cadmium, whereas in females the peri-implantation period of pregnancy is sensitive. To examine the potential roles of the cadmium-binding protein, metallothionein (MT), in the reproductive toxicology of cadmium, we examined a transgenic mouse strain that overexpresses metallothionein-I (MT-I). These mice had dramatically increased steady-state levels of MT-I mRNA and MT in the testes and in the female reproductive tract during the peri-implantation period of pregnancy, and this overexpression occurred in a cell-specific and temporally regulated manner similar to that of the endogenous MT-I gene. …

Go to article

Stimulation Of Alpha 1(I) Procollagen Gene Expression In Nih-3t3 Cells By The Human T Cell Leukemia Virus Type 1 (Htlv-1) Tax Gene., E. Munoz, D. Suri, S. Amini, K. Khalili, Sergio A. Jimenez Nov 1995

Stimulation Of Alpha 1(I) Procollagen Gene Expression In Nih-3t3 Cells By The Human T Cell Leukemia Virus Type 1 (Htlv-1) Tax Gene., E. Munoz, D. Suri, S. Amini, K. Khalili, Sergio A. Jimenez

Selected Works of Sergio Jiménez, MD, MACR

The mechanisms that regulate the expression of genes encoding extracellular matrix proteins in fibroblasts and other mesenchymal cells have remained elusive. Studies from several laboratories have indicated that Tax, a trans-regulatory protein from the human T cell leukemia virus type I not only augments viral gene expression but also triggers the expression of various cellular genes. Here, we examined the hypothesis that the expression of collagen genes may also be modulated by Tax. NIH-3T3 cells were simultaneously transfected with a Tax expressor plasmid and a chimeric construct containing regulatory sequences (-804 to +42 bp) of the alpha 1(I) procollagen gene …

Go to article

Expression Of Genes Encoding Antioxidant Enzymes In Preimplantation Mouse And Cow Embryos And Primary Bovine Oviduct Cultures Employed For Embryo Coculture., M B Harvey, M Y Arcellana-Panlilio, X Zhang, G A Schultz, A J Watson Sep 1995

Expression Of Genes Encoding Antioxidant Enzymes In Preimplantation Mouse And Cow Embryos And Primary Bovine Oviduct Cultures Employed For Embryo Coculture., M B Harvey, M Y Arcellana-Panlilio, X Zhang, G A Schultz, A J Watson

Obstetrics & Gynaecology Publications

Preimplantation embryos from a variety of mammalian species contrast markedly in their response to culture in vitro. Murine preimplantation embryos display a wider tolerance than other mammalian species to culture environments, and this has contributed to the development of several effective defined culture media. Embryo coculture on somatic cells remains the most effective method of supporting reasonable rates of bovine preimplantation development in vitro. The patterns of gene expression for several antioxidant enzymes during preimplantation murine and bovine development were examined by use of the reverse transcription-polymerase chain reaction technique to determine whether the differential developmental capacity of mammalian preimplantation …

Go to article

Astrocytes Derived From P53-Deficient Mice Provide A Multistep In Vitro Model For Development Of Malignant Gliomas., Alan M. Yahanda Md, Facs, J M Bruner, L A Donehower, R S Morrison Aug 1995

Astrocytes Derived From P53-Deficient Mice Provide A Multistep In Vitro Model For Development Of Malignant Gliomas., Alan M. Yahanda Md, Facs, J M Bruner, L A Donehower, R S Morrison

PCI Publications and Projects

Loss or mutation of p53 is thought to be an early event in the malignant transformation of many human astrocytic tumors. To better understand the role of p53 in their growth and transformation, we developed a model employing cultured neonatal astrocytes derived from mice deficient in one (p53 +/-) or both (p53 -/-) p53 alleles, comparing them with wild-type (p53 +/+) cells. Studies of in vitro and in vivo growth and transformation were performed, and flow cytometry and karyotyping were used to correlate changes in growth with genomic instability. Early-passage (EP) p53 -/- astrocytes achieved higher saturation densities and had …

Go to article

The Rat Tram Flap: A Human Analogue?, Geoffrey G. Hallock Md Jul 1995

The Rat Tram Flap: A Human Analogue?, Geoffrey G. Hallock Md

Department of Surgery

No abstract provided.

Go to article

Increased Alpha 1(I) Procollagen Gene Expression In Tight Skin (Tsk) Mice Myocardial Fibroblasts Is Due To A Reduced Interaction Of A Negative Regulatory Sequence With Ap-1 Transcription Factor., Neena Philips, Reza I. Bashey, Sergio A. Jimenez Apr 1995

Increased Alpha 1(I) Procollagen Gene Expression In Tight Skin (Tsk) Mice Myocardial Fibroblasts Is Due To A Reduced Interaction Of A Negative Regulatory Sequence With Ap-1 Transcription Factor., Neena Philips, Reza I. Bashey, Sergio A. Jimenez

Department of Medicine Faculty Papers

The TSK mouse, a model of fibrosis, displays exaggerated connective tissue accumulation in skin and visceral organs including the heart. To study the mechanisms of myocardial fibrosis in TSK mice, we established several strains of TSK mice myocardial fibroblasts in culture and examined the regulation of collagen gene expression in these cells. These strains displayed increased collagen gene expression in comparison with myocardial fibroblasts established from normal mice. On an average, the TSK myocardial fibroblast cultures showed a 4-fold increase in collagen synthesis and 4.4- and 3.6-fold increases, respectively, in alpha 1(I) and alpha 1(III) collagen mRNA steady state levels. …

Go to article

Epidermal Growth Factor Coordinately Regulates The Expression Of Prostaglandin G/H Synthase And Cytosolic Phospholipase A2 Genes In Embryonic Mouse Cells., Kenneth P. Chepenik, Arturo Diaz, Sergio A. Jimenez Aug 1994

Epidermal Growth Factor Coordinately Regulates The Expression Of Prostaglandin G/H Synthase And Cytosolic Phospholipase A2 Genes In Embryonic Mouse Cells., Kenneth P. Chepenik, Arturo Diaz, Sergio A. Jimenez

Department of Medicine Faculty Papers

Confluent, primary cultures of mouse embryo palate mesenchyme (MEPM) cells are refractory to activation of phospholipase A2 (PLA2) by the calcium ionophore A23187. However, treatment of these cultures with epidermal growth factor (EGF) permits the cells to activate PLA2 in response to A23187. We have developed this finding by exploring molecular mechanisms by which growth factors modulate mobilization and metabolism of arachidonic acid. We found chronic treatment (> 6 h) of confluent MEPM cells with EGF (a) increases their ability to metabolize exogenous arachidonic acid to prostaglandin E2 (PGE2) and (b) stimulated constitutive expression of activities of PLA2 and cyclooxygenase …

Go to article

A Thyroid Hormone-Regulated Gene In Xenopus Laevis Encodes A Type Iii Iodothyronine 5-Deiodinase., Donald L. St Germain, Robert Schwartzman, Walburga Croteau, Akira Kanamori, Zhou Wang, Donald D. Brown, Valerie Galton Aug 1994

A Thyroid Hormone-Regulated Gene In Xenopus Laevis Encodes A Type Iii Iodothyronine 5-Deiodinase., Donald L. St Germain, Robert Schwartzman, Walburga Croteau, Akira Kanamori, Zhou Wang, Donald D. Brown, Valerie Galton

Dartmouth Scholarship

The type III iodothyronine 5-deiodinase metabolizes thyroxine and 3,5,3'-triiodothyronine to inactive metabolites by catalyzing the removal of iodine from the inner ring. The enzyme is expressed in a tissue-specific pattern during particular stages of development in amphibia, birds, and mammals. Recently, a PCR-based subtractive hybridization technique has been used to isolate cDNAs prepared from Xenopus laevis tadpole tail mRNA that represent genes upregulated by thyroid hormone during metamorphosis. Sequence analysis of one of these cDNAs (XL-15) revealed regions of homology to the mRNA encoding the rat type I (outer ring) 5'-deiodinase, including a conserved UGA codon that encodes selenocysteine in …

Go to article

Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper Jul 1994

Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper

Dartmouth Scholarship

Depression of the cellular immune response to Toxoplasma gondii has been reported in both mice and humans. The present study was undertaken to determine the kinetics and mechanism of the observed downregulation of interleukin 2 (IL-2) production during experimental murine toxoplasmosis. For these investigations, the cell-mediated immune response to the wild type (PTg) was compared with that to the less-virulent mutant parasite (PTgB), which is deficient in the major surface antigen, p30 (SAG-1). Spleen cells from infected A/J mice failed to proliferate in response to Toxoplasma antigens during the first week of infection. Both PTg- and PTgB-infected A/J mice exhibited …

Go to article

Actions Of (1s,3r)-1-Aminocyclopentane-1,3-Dicarboxylic Acid (1s,3r-Acpd) In Retinal On Bipolar Cells Indicate That It Is An Agonist At L-Ap4 Receptors., Wallace B. Thoreson, R. F. Miller Jun 1994

Actions Of (1s,3r)-1-Aminocyclopentane-1,3-Dicarboxylic Acid (1s,3r-Acpd) In Retinal On Bipolar Cells Indicate That It Is An Agonist At L-Ap4 Receptors., Wallace B. Thoreson, R. F. Miller

Journal Articles: Ophthalmology

Metabotropic glutamate receptors (mGluRs) include receptors sensitive to L-2-amino-4-phosphonobutyrate (L-AP4) and 1S,3R-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD). To determine whether 1S,3R-ACPD is an agonist at retinal L-AP4 receptors, whole cell voltage clamp recordings were obtained from mudpuppy ON bipolar cells in a superfused retinal slice and L-AP4 and 1S,3R-ACPD were bath applied. Both compounds evoked similar outward currents which reversed near 0 mV and were accompanied by an increased input resistance. Responses to both agonists washed out in parallel suggesting they act through the same second messenger pathway(s). Inhibitors of cGMP-PDE activity suppressed responses to both L-AP4 and 1SR,3RS-ACPD, suggesting that both compounds …

Go to article

Functional Analysis Of Human Alpha 1(I) Procollagen Gene Promoter. Differential Activity In Collagen-Producing And -Nonproducing Cells And Response To Transforming Growth Factor Beta 1., Sergio A. Jimenez, John A. Varga, Anne Olsen, Liye Li, Arturo Diaz, Janet Herhal, Julie Koch Apr 1994

Functional Analysis Of Human Alpha 1(I) Procollagen Gene Promoter. Differential Activity In Collagen-Producing And -Nonproducing Cells And Response To Transforming Growth Factor Beta 1., Sergio A. Jimenez, John A. Varga, Anne Olsen, Liye Li, Arturo Diaz, Janet Herhal, Julie Koch

Department of Medicine Faculty Papers

To gain a further understanding of the regulation of human type I collagen gene expression under physiologic and pathologic conditions, we characterized 5.3 kilobase pairs (kb) of the human alpha 1(I) procollagen gene promoter. A series of deletion constructs containing portions of the alpha 1(I) procollagen 5'-flanking region (with end points from -5.3 kb to -84 base pairs (bp)) ligated to the chloramphenicol acetyltransferase (CAT) reporter gene were transiently transfected into NIH/3T3 cells. Maximal CAT activity was observed with constructs having 5' end points from -804 to -174 bp. A further 5' deletion to -84 bp caused a marked reduction …

Go to article

Preimplantation Development Of In Vitro-Matured And In Vitro-Fertilized Ovine Zygotes: Comparison Between Coculture On Oviduct Epithelial Cell Monolayers And Culture Under Low Oxygen Atmosphere., A J Watson, P H Watson, D Warnes, S K Walker, D T Armstrong, R F Seamark Apr 1994

Preimplantation Development Of In Vitro-Matured And In Vitro-Fertilized Ovine Zygotes: Comparison Between Coculture On Oviduct Epithelial Cell Monolayers And Culture Under Low Oxygen Atmosphere., A J Watson, P H Watson, D Warnes, S K Walker, D T Armstrong, R F Seamark

Obstetrics & Gynaecology Publications

The roles of medium composition, serum source, embryo coculture, and culture under low O2 conditions on the development of in vitro-matured and in vitro-fertilized (IVMF) ovine zygotes were investigated in three separate experiments. In the first experiment, the proportion of cocultured IVMF zygotes developing to the blastocyst stage was significantly higher (38.0% vs. 3.5%; p < 0.05) than that of non-cocultured zygotes treated within three embryo culture media (TCM-199 + 10% fetal bovine serum [FBS]; bicarbonate-buffered, glucose-free synthetic oviduct fluid medium [mod-SOFM] + 10% FBS; and bicarbonate-buffered BSA-free Tyrode's salt solution [mod-TALP] + 10% FBS) under a 5% CO2 atmosphere in air. In a second experiment, a significantly higher (p < 0.05) proportion of cocultured zygotes placed in TCM-199 medium survived to the blastocyst stage (37.4% blastocysts vs. 23.4% in mod-SOFM). No significant effect of serum (FBS vs. human serum [HS]) was observed on embryonic development, but coculture was confirmed to exert a significant influence on development to the blastocyst stage. In the final experiment, survival of the embryo under a reduced oxygen (5% CO2:5% O2:90% N2) atmosphere was investigated. In contrast to results in the initial experiments, embryonic survival was significantly higher (p < 0.05) in the non-cocultured treatment groups (21.9% blastocysts vs. 0.4% for cocultured zygotes). Serum source also had a significant (p < 0.05) influence upon the development of non-cocultured zygotes: 32.3% of zygotes cultured with HS progressed to the blastocyst stage vs. 11.5% of zygotes cultured in FBS-supplemented medium. These results have characterized two distinct culture environments, each capable of supporting the development of high frequencies of unselected IVMF zygotes to the blastocyst stage in vitro.

Go to article

A Growth Factor Phenotype Map For Ovine Preimplantation Development., A J Watson, P H Watson, M Arcellana-Panlilio, D Warnes, S K Walker, G A Schultz, D T Armstrong, R F Seamark Apr 1994

A Growth Factor Phenotype Map For Ovine Preimplantation Development., A J Watson, P H Watson, M Arcellana-Panlilio, D Warnes, S K Walker, G A Schultz, D T Armstrong, R F Seamark

Obstetrics & Gynaecology Publications

The reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the patterns of expression for several growth factor ligand and receptor genes during ovine preimplantation development. Transcripts for insulin-like growth factor (IGF)-I, IGF-II, and the receptors for insulin and IGF-I were detected throughout ovine preimplantation development from the 1-cell to the blastocyst stage. Transforming growth factor alpha (TGF alpha) transcripts were also detected throughout ovine preimplantation development. The mRNAs encoding basic fibroblast growth factor (bFGF) were detected in all stages of the ovine preimplantation embryo, although the relative abundance of this transcript consistently decreased from the 1-cell to the blastocyst …

Go to article

Possible Roles Of Insulin And Insulin-Like Growth Factors In Rat Preimplantation Development: Investigation Of Gene Expression By Reverse Transcription-Polymerase Chain Reaction., X Zhang, G M Kidder, A J Watson, G A Schultz, D T Armstrong Mar 1994

Possible Roles Of Insulin And Insulin-Like Growth Factors In Rat Preimplantation Development: Investigation Of Gene Expression By Reverse Transcription-Polymerase Chain Reaction., X Zhang, G M Kidder, A J Watson, G A Schultz, D T Armstrong

Obstetrics & Gynaecology Publications

The sensitive mRNA phenotyping technique of reverse transcription-polymerase chain reaction was used to demonstrate that insulin receptor mRNA is present in rat embryos during the preimplantation period. In addition, mRNA encoding insulin-like growth factor (IGF) type I and type II receptors have also been detected in rat preimplantation embryos. IGF-I mRNA was not detected in preimplantation embryos but was found in oviducts and uteri of prepubertal and early pregnant rats. IGF-II mRNA was present in both embryos and in oviducts and uteri during the preimplantation period. These findings suggest that insulin and IGF-I could influence early embryo development in endocrine …

Go to article

The Tight Skin Mouse: Demonstration Of Mutant Fibrillin-1 Production And Assembly Into Abnormal Microfibrils, Cay M. Kielty, Michael Raghunath, Linda D. Siracusa, Michael J. Sherratt, Reiner Peters, C. Adrian Shuttleworth, Sergio A. Jimenez Mar 1993

The Tight Skin Mouse: Demonstration Of Mutant Fibrillin-1 Production And Assembly Into Abnormal Microfibrils, Cay M. Kielty, Michael Raghunath, Linda D. Siracusa, Michael J. Sherratt, Reiner Peters, C. Adrian Shuttleworth, Sergio A. Jimenez

Selected Works of Sergio Jiménez, MD, MACR

Mice carrying the Tight skin (Tsk) mutation harbor a genomic duplication within the fibrillin-1 (Fbn 1) gene that results in a larger than normal in-frame Fbn 1 transcript. In this study, the consequences of the Tsk mutation for fibrillin-containing microfibrils have been examined. Dermal fibroblasts from Tsk/+ mice synthesized and secreted both normal fibrillin (approximately 330 kD) and the mutant oversized Tsk fibrillin-1 (approximately 450 kD) in comparable amounts, and Tsk fibrillin-1 was stably incorporated into cell layers. Immunohistochemical and ultrastructural analyses of normal and Tsk/+ mouse skin highlighted differences in the gross organization and distribution of microfibrillar arrays. Rotary …

Go to article

How To Make A Blastocyst., A J Watson, G M Kidder, G A Schultz Oct 1992

How To Make A Blastocyst., A J Watson, G M Kidder, G A Schultz

Obstetrics & Gynaecology Publications

Several of the new reproductive technologies have been cultivated from our current understanding of the genetic programming and cellular processes that are involved in the major morphogenetic events of mammalian preimplantation development. Research directed at characterizing the patterns of gene expression during early development has shown that the embryo is initially under maternal control and later superseded by new transcriptional activity provided by the activation of the embryonic genome. Several embryonic transcripts encoding: (i) growth factors, (ii) cell junctions, (iii) plasma membrane ion transporters, and (iv) cell adhesion molecules have been identified as contributing directly to the progression of the …

Go to article

Cytolytic T Lymphocytes Specific For Tumors And Infected Cells From Mice With A Retrovirus-Induced Immunodeficiency Syndrome., Jennifer G. Erbe, Kathy A. Green, Karen M. Crassi, Herbert C. Morse, W R. Green May 1992

Cytolytic T Lymphocytes Specific For Tumors And Infected Cells From Mice With A Retrovirus-Induced Immunodeficiency Syndrome., Jennifer G. Erbe, Kathy A. Green, Karen M. Crassi, Herbert C. Morse, W R. Green

Dartmouth Scholarship

LP-BM5 retrovirus complex-infected C57BL/6 mice develop immunodeficiency, somewhat analogous to AIDS, termed murine AIDS (MAIDS). After secondary stimulation with syngeneic B-cell lymphomas from LP-BM5-infected mice, C57BL/6 mice produced vigorous CD8+ cytotoxic T lymphocytes specific for MAIDS-associated tumors. An anti-LP-BM5 specificity was suggested because spleen and lymph node cells from LP-BM5-infected mice served as target cells in competition assays, and cells from LP-BM5, but not ecotropic, virus-infected mice functioned as secondary in vitro stimulators to generate cytotoxic T lymphocytes to MAIDS tumors.

Go to article

Expression Of A Human Cartilage Procollagen Gene (Col2a1) In Mouse 3t3 Cells., Leena Ala-Kokko, James Hyland, Carol Smith, Kari I. Kivirikko, Sergio A. Jimenez, Darwin J. Prockop Aug 1991

Expression Of A Human Cartilage Procollagen Gene (Col2a1) In Mouse 3t3 Cells., Leena Ala-Kokko, James Hyland, Carol Smith, Kari I. Kivirikko, Sergio A. Jimenez, Darwin J. Prockop

Department of Medicine Faculty Papers

Expression in a recombinant system has been difficult to obtain for any of the major fibrillar collagens that require processing by eight or more post-translational enzymes. Here, two DNA constructs were designed so that the promoter region of the gene for the pro-alpha 1(I) chain of human type I procollagen drove expression of the human type II procollagen gene in mouse NIH 3T3 cells, a culture line that normally synthesizes type I procollagen but not any cartilage-specific protein such as type II procollagen. Both constructs were expressed as both mRNA and protein. In clones expressing the construct at high levels, …

Go to article

The Role Of Calcium Ions In Toxic Cell Injury., John L. Farber Mar 1990

The Role Of Calcium Ions In Toxic Cell Injury., John L. Farber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Calcium ions have been increasingly implicated as a mediator of the mechanisms generating lethal cell injury under a variety of pathologic circumstances. An overview of the various roles suggested for such alterations in cellular calcium homeostasis is presented. The central role of plasma membrane damage in the genesis of irreversible cell injury is used to divide the postulated roles for calcium ions into two major mechanisms. On the one hand, calcium ions have been proposed as mediators of the functional consequences of plasma membrane injury. An influx of extracellular calcium ions across a damaged permeability barrier and down a steep …

Go to article

Susceptibility Of Hepatic Microcirculation To Reperfusion Injury: A Comparison Of Adult And Suckling Rats., Alan M. Yahanda Md, Facs, C N Paidas, M G Clemens Feb 1990

Susceptibility Of Hepatic Microcirculation To Reperfusion Injury: A Comparison Of Adult And Suckling Rats., Alan M. Yahanda Md, Facs, C N Paidas, M G Clemens

Other Specialties

Primary graft failure and vascular thromboses are frequent complications of liver transplantation, yet the mechanisms responsible remain unclear. Previous work from our laboratory has shown that hepatic reperfusion injury results in damage at the microvessel level. The present study was performed to determine whether an increased susceptibility of immature animals to microvascular injury during reperfusion might be a contributing factor in these complications. Suckling (35 to 50 g) or adult (250 to 400 g) rats were subjected to 30 or 60 minutes of hepatic ischemia to the left and median lobes followed by 90 minutes of reperfusion. Control animals were …

Go to article

Animal Bite Infections., Joel D. Klein, Md Jan 1989

Animal Bite Infections., Joel D. Klein, Md

Department of Pediatrics Faculty Papers

Animal bites have become alarmingly common and may represent a quiet epidemic. It is estimated that between 1 and 3.5 million animal bites occur annually in the United States. The highest incidence has consistently been in 5-to-14-year-old schoolchildren, who have greater contact with animals, especially house pets, on a daily basis. This article discusses the epidemiology, microbiology, clinical findings and management of animal bites infections.

Go to article

Physical Linkage Of The Genes For Platelet Membrane Glycoproteins Iib And Iiia., Paul F. Bray, Greg Barsh, Jean-Philippe Rosa, Xue Ya Luo, Ellen Magenis, Marc A. Shuman Nov 1988

Physical Linkage Of The Genes For Platelet Membrane Glycoproteins Iib And Iiia., Paul F. Bray, Greg Barsh, Jean-Philippe Rosa, Xue Ya Luo, Ellen Magenis, Marc A. Shuman

Cardeza Foundation for Hematologic Research

The fibrinogen receptor on human platelets is a prototypic member of the integrin family and is composed of subunit glycoproteins IIb (gpIIb) and IIIa (gpIIIa) in a 1:1 stoichiometric ratio. We have isolated cDNA clones for gpIIb and gpIIIa and localized both genes to chromosome 17. In the current study, several approaches were used to localize and map the genes for gpIIb and gpIIIa. A preliminary evaluation of subchromosomal localization was performed by using a panel of mouse-human somatic cell hybrids that contain different amounts of the long arm of human chromosome 17. Southern hybridization to the DNA of these …

Go to article

First Prev Next Last