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1.
Animal ; 8(2): 217-23, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24230485

ABSTRACT

The aim of this study was to estimate genetic correlations between milk yield, somatic cell score (SCS), mastitis, and claw and leg disorders (CLDs) during first lactation in Holstein cows by using a threshold-linear random regression test-day model. We used daily records of milk, fat and protein yields; somatic cell count (SCC); and mastitis and CLD incidences from 46 771 first-lactation Holstein cows in Hokkaido, Japan, that calved between 2000 and 2009. A threshold animal model for binary records (mastitis and CLDs) and linear animal model for yield traits were applied in our multiple trait analysis. For both liabilities and yield traits, additive genetic effects were used as random regression on cubic Legendre polynomials of days on milk. The highest positive genetic correlations between yields and disease incidences (0.36 for milk and mastitis, 0.56 for fat and mastitis, 0.24 for protein and mastitis, 0.32 for milk and CLD, 0.44 for fat and CLD and 0.31 for protein and CLD) were estimated at about the time of peak milk yield (36 to 65 days in milk). Selection focused on early lactation yield may therefore increase the risk of mastitis and CLDs. The positive genetic correlations of SCS with mastitis or CLD incidence imply that selection to reduce SCS in the early stages of lactation would decrease the incidence of both mastitis and CLD.


Subject(s)
Cattle Diseases/epidemiology , Cattle Diseases/genetics , Cattle/genetics , Foot Diseases/veterinary , Mastitis, Bovine/genetics , Milk/chemistry , Animals , Female , Foot Diseases/epidemiology , Foot Diseases/genetics , Genetic Association Studies/veterinary , Japan/epidemiology , Mastitis, Bovine/epidemiology , Regression Analysis
2.
Neuroscience ; 264: 4-16, 2014 Apr 04.
Article in English | MEDLINE | ID: mdl-24144622

ABSTRACT

During all stages of neural development-from the fate switches of neural precursor/progenitor cells to activity-dependent synapse maturation-chromatin-level modifications are important regulators of the gene expression that control developmental programs. Such modifications, including both alterations of histone tails and cytosine residues in the DNA, as well as changes in the chromatin structure, act dynamically throughout development and work together to determine the chromatin state at each time point. While many studies have shown localized action of chromatin modifiers at relevant gene loci, recent reports have also indicated that some chromatin modifications work on a more global scale, altering many loci throughout the genome. Here we review recent papers that describe the roles of chromatin-level regulation, at both the local and global scale, in the development of the mouse brain.


Subject(s)
Brain/growth & development , Chromatin Assembly and Disassembly/genetics , Epigenesis, Genetic , Neural Stem Cells/physiology , Animals , Mice
3.
Pharmazie ; 68(6): 406-13, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23875246

ABSTRACT

We recently developed a prodrug (AS1932804-00, CMP) of the novel FVIIa inhibitor AS1924269-00, which possesses a carbamate amidine backbone. In addition, we developed another type of prodrug (AS1927819-00, OXP) with an oxime amidine backbone. In this study, we investigated the efficiency of conversion of these novel FVIIa prodrugs to their active forms by evaluating the production of the active form in vitro by using microsomes, mitochondria, and cryopreserved hepatocytes, and compared it with the in vivo conversion mechanisms of the prodrugs (oxime amidine vs. carbamate amidine). We observed that OXP and CMP showed improved oral absorption, and the efficiency of conversion of CMP to the active form was higher than that of OXP. The in vivo rate of conversion of OXP to its active form was low in rats, and compared to liver microsomes and mitochondria, cryopreserved hepatocytes supplemented with serum and coenzymes were an appropriate metabolic test tool. On the other hand, the efficiency of conversion of CMP to its active from could be appropriately evaluated using small intestinal microsomes. The development of a prodrug can be optimized when information about the stability of carboxylic acid esters in the presence of serum esterases, membrane permeability of intermediate forms, and differential tissue specificity to metabolic activities for carbamate and oxime backbones of amidine can be obtained.


Subject(s)
Anticoagulants/pharmacokinetics , Factor VIIa/antagonists & inhibitors , Phenoxyacetates/pharmacokinetics , Animals , Azetidines/pharmacokinetics , Benzylamines/pharmacokinetics , Biotransformation , Hepatocytes/metabolism , In Vitro Techniques , Intestinal Mucosa/metabolism , Kinetics , Microsomes, Liver/metabolism , Mitochondria, Liver/metabolism , NAD/metabolism , NADP/metabolism , Prodrugs/metabolism , Rats
4.
Pharmazie ; 68(5): 349-54, 2013 May.
Article in English | MEDLINE | ID: mdl-23802432

ABSTRACT

AS1924269-00 is a promising orally applicable anticoagulant that inhibits FVIIa but has very low oral absorption. Therefore, in this study, we aimed to develop a prodrug of AS1924269-00, which possesses a carbamate-added amidine functional group, with high membrane permeability. We investigated the pharmacokinetics of the carbamate-type prodrug of AS1924269-00 in rats. The Caco-2 cell monolayer was used as an in vitro model and in parallel an artificial membrane permeability assay (PAMPA) was performed to examine the transport mechanisms of the prodrug. The bioavailability of the active form was determined to be only 0.3% in rats, but the oral absorption of the prodrug was markedly improved, and its bioavailability was 36%. Our in vivo result was consistent with the finding that compared to AS1924269-00, the prodrug showed favorable permeability in Caco-2 cells and PAMPA. We introduced carbamate into the amidine functional group of the FVIIa inhibitor, which possesses the amidine backbone, and converted it to a prodrug using carboxylic acid ethyl ester. This novel prodrug had favorable absorption and membrane permeability in vivo and in vitro. Thus, we suggest a clinical application of the carbamate-added amidine prodrug of the FVIIa inhibitor.


Subject(s)
Amidines/pharmacokinetics , Anticoagulants/pharmacokinetics , Factor VIIa/antagonists & inhibitors , Phenoxyacetates/pharmacokinetics , Amidines/administration & dosage , Animals , Anticoagulants/administration & dosage , Caco-2 Cells , Chromatography, High Pressure Liquid , Half-Life , Humans , Indicators and Reagents , Male , Mass Spectrometry , Membranes, Artificial , Permeability , Phenoxyacetates/administration & dosage , Rats , Rats, Sprague-Dawley
5.
Animal ; 7(9): 1423-8, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23597286

ABSTRACT

We investigated the relationships between conception rates (CRs) at first service in Japanese Holstein heifers (i.e. animals that had not yet had their first calf) and cows and their test-day (TD) milk yields. Data included records of artificial insemination (AI) for heifers and cows that had calved for the first time between 2000 and 2008 and their TD milk yields at 6 through 305 days in milk (DIM) from first through third lactations. CR was defined as a binary trait for which first AI was a failure or success. A threshold-linear animal model was applied to estimate genetic correlations between CRs of heifers or cows and TD milk yield at various lactation stages. Two-trait genetic analyses were performed for every combination of CR and TD milk yield by using the Bayesian method with Gibbs sampling. The posterior means of the heritabilities of CR were 0.031 for heifers, 0.034 for first-lactation cows and 0.028 for second-lactation cows. Heritabilities for TD milk yield increased from 0.324 to 0.433 with increasing DIM but decreased slightly after 210 DIM during first lactation. These heritabilities from the second and third lactations were higher during late stages of lactation than during early stages. Posterior means of the genetic correlations between heifer CR and all TD yields were positive (range, 0.082 to 0.287), but those between CR of cows and milk yields during first or second lactation were negative (range, -0.121 to -0.250). Therefore, during every stage of lactation, selection in the direction of increasing milk yield may reduce CR in cows. The genetic relationships between CR and lactation curve shape were quite weak, because the genetic correlations between CR and TD milk yield were constant during the lactation period.


Subject(s)
Breeding/methods , Dairying/methods , Fertilization/genetics , Fertilization/physiology , Lactation/physiology , Milk/metabolism , Phenotype , Animals , Bayes Theorem , Cattle , Female , Japan , Linear Models
6.
Oncogene ; 32(34): 3954-64, 2013 Aug 22.
Article in English | MEDLINE | ID: mdl-23001041

ABSTRACT

The transcription factor E2F1 has pivotal roles in both cell proliferation and cell death, and is an important molecular target in cancer. Under proliferative conditions E2F1 induces the expression of genes that promote cell cycle progression, such as E2F2, whereas under proapoptotic conditions E2F1 induces expression of genes such as p73 that lead to apoptosis. The mechanism by which the apoptotic function of E2F1 is activated remains unclear, however. We now show that members of the E2F family are covalently conjugated with the ubiquitin-like modifier NEDD8. Overexpression of SENP8, a NEDD8-specific cysteine protease, resulted in deNEDDylation of E2F1 and promoted its transactivation activity at the p73 gene but not at the E2F2 gene. Knockdown of SENP8, on the other hand, attenuated p73 expression and apoptosis induced by E2F1 or by DNA damage. SENP8 also promoted the interaction between E2F1 and its cofactor Microcephalin 1, which is required for p73 induction. These results suggest that NEDDylation is a molecular trigger that modifies the target specificity of E2F1, and could have important implications for E2F1 regulation of apoptosis.


Subject(s)
Apoptosis , E2F1 Transcription Factor/metabolism , Endopeptidases/metabolism , Ubiquitins/metabolism , Cell Line, Tumor , DNA Damage , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , E2F1 Transcription Factor/genetics , Endopeptidases/genetics , Flow Cytometry , HEK293 Cells , Humans , Immunoblotting , Lysine/genetics , Lysine/metabolism , Models, Genetic , NEDD8 Protein , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Transcriptional Activation , Tumor Protein p73 , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Ubiquitins/genetics
7.
Lett Appl Microbiol ; 55(2): 135-40, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22642647

ABSTRACT

AIMS: To evaluate the protective effects of oral administration of milk fermented with a Lactococcus strain against influenza virus (IFV) infection in a mouse model. METHODS AND RESULTS: Milk fermented with exopolysaccharide-producing Lactococcus lactis subsp. cremoris (L. cremoris) FC was orally administered to BALB/c mice for 12 days. Mice were intranasally infected with IFV A/New Caledonia/20/99 (H1N1) on day 8, and survival was determined for 14 days after IFV infection. Survival rate and body weight loss after IFV infection in the L. cremoris FC fermented milk-administered group were significantly improved compared with those in the control group. In the unfermented milk-administered group, survival rate was not improved, whereas body weight loss was slightly improved compared with that in the control group. The mean virus titre in the lung of the L. cremoris FC fermented milk-administered group 3 days after infection was significantly decreased compared with that in the control group. CONCLUSIONS: These results suggest that oral administration of milk fermented with L. cremoris FC protects mice against IFV infection. SIGNIFICANCE AND IMPACT OF THE STUDY: These results demonstrate that oral administration of milk fermented with exopolysaccharide-producing Lactococcus strains might protect host animals against IFV infection.


Subject(s)
Influenza A Virus, H1N1 Subtype , Lactococcus lactis/metabolism , Milk , Orthomyxoviridae Infections/immunology , Probiotics/administration & dosage , Administration, Oral , Animals , Female , Fermentation , Lung/pathology , Lung/virology , Mice , Mice, Inbred BALB C , Milk/metabolism , Milk/microbiology , Survival Rate
8.
J Dairy Sci ; 94(4): 2103-7, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21427001

ABSTRACT

Mastitis is a common infectious disease of the mammary gland and a major problem in the dairy industry. We previously reported that forebrain embryonic zinc finger-like (FEZL) encoding a stretch of 12 glycines (p.Gly105[12]) instead of 13 glycines (p.Gly105[13]) is associated with a lower somatic cell score (SCS) in a family derived from Walkway Chief Mark. Here we report that the p.Gly105[12] allele is associated with a significantly decreased incidence of clinical mastitis in a large Holstein population. We genotyped the FEZL polymorphism in 918 randomly collected Holstein sires, and investigated the effect of the polymorphism on the estimated breeding value (EBV) for SCS and milk, fat, solids-not-fat, and protein yield, and on the number of cattle with clinical mastitis among daughters derived from these sires. The average EBV for SCS among sires carrying the heterozygous p.Gly105[12] was significantly lower than that among sires carrying the homozygous p.Gly105[13], whereas we found no unfavorable effects of this polymorphism on EBV for milk, fat, solids-not-fat, and protein yield. The proportion of cows with clinical mastitis derived from sires carrying heterozygous p.Gly105[12] was significantly lower than that of daughters derived from sires carrying the homozygous p.Gly105[13]. Thus, selection of sires carrying p.Gly105[12] could be beneficial in the dairy industry by reducing the incidence of mastitis.


Subject(s)
Cattle/genetics , Mastitis, Bovine/genetics , Polymorphism, Genetic/genetics , Zinc Fingers/genetics , Animals , Cell Count/veterinary , Female , Genotype , Male
9.
J Synchrotron Radiat ; 17(6): 813-6, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20975230

ABSTRACT

The understanding of and in situ observation of the transport and distribution of water in carbon-paper gas diffusion layers (GDLs) using non-destructive imaging techniques is critical for achieving high performance in polymer electrolyte fuel cells (PEFCs). To investigate the behavior of water in GDLs of PEFCs, phase-contrast X-ray imaging via X-ray interferometric imaging (XII) and diffraction-enhanced imaging (DEI) were performed using 35 keV X-rays. The XII technique is useful for the radiographic imaging of GDLs and in situ observations of water evolution processes in operating PEFCs. DEI provides a way for tomographic imaging of GDLs in PEFCs. Because high-energy X-rays are applicable to the imaging of both carbon papers and heavy materials, which make up PEFCs, phase-contrast X-ray imaging techniques have proven to be valuable for investigation of GDLs.

10.
Int J Clin Pharmacol Ther ; 48(3): 214-23, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20197016

ABSTRACT

OBJECTIVES: This study was aimed at evaluating the pharmacokinetics and pharmacodynamics of basiliximab in Japanese pediatric renal transplant patients. MATERIALS AND METHODS: This study was carried out with the approval of the Institutional Review Board of our institution. Written consent was obtained from the legal representative of each patient, as also from the patients themselves where possible. Eligible patients were Japanese pediatric patients weighing less than 35 kg and younger than 15 years of age who were scheduled to undergo renal transplantation. Each patient was given intravenous basiliximab at the total dose of 20 mg administered in two divided doses of 10 mg each on the day of transplantation and on the fourth day after transplantation. Cyclosporine and corticosteroids were also administered as the basic concomitant maintenance immunosuppressive therapy. The time course of changes in the serum basiliximab concentrations and the percentage of CD25+ T-lymphocytes in the peripheral blood were determined up to 26 weeks after the transplantation to calculate the period of suppression of the CD25+ T-lymphocytes. Serum basiliximab was measured by an ELISA technique, and the percentage of CD25+ T-lymphocytes in the peripheral blood was determined by flow cytometry. RESULTS: 6 Japanese pediatric patients weighing less than 35 kg and aged over 1 year and less than 15 years who were scheduled to undergo renal transplantation were enrolled in this study. In regard to the time course of changes of the serum basiliximab concentration, after the peak serum concentration was reached, basiliximab was gradually eliminated from the blood with a mean half-life of 7.06 days. CD25+ T-lymphocytes in the peripheral blood were suppressed completely when the serum concentration of basiliximab was over 0.2 microg/ml, and the period of suppression of the CD25+ T cells was 40.3 - 51.7 days (mean +/- SD; 45.8 +/- 4.9). CONCLUSION: Changes in the serum concentration of basiliximab and the period of suppression of CD25+ peripheral blood T-lymphocytes in Japanese pediatric renal transplant patients were similar to those reported for non-Japanese pediatric transplant patients and Japanese adult renal transplant patients with a cyclosporine and corticosteroid regimen. This indicates that expected efficacy can be obtained in Japanese pediatric renal transplant patients using the recommended dosing regimens validated by non-Japanese studies.


Subject(s)
Antibodies, Monoclonal/pharmacology , Immunosuppressive Agents/pharmacology , Kidney Transplantation , Recombinant Fusion Proteins/pharmacology , Antibodies, Monoclonal/pharmacokinetics , Basiliximab , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Half-Life , Humans , Immunosuppressive Agents/pharmacokinetics , Infant , Japan , Male , Recombinant Fusion Proteins/pharmacokinetics , T-Lymphocytes/metabolism
11.
Neuropediatrics ; 37(3): 159-62, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16967368

ABSTRACT

We report on two children with acute encephalopathy showing mild clinical manifestations and reversible white matter lesions. In both patients, MRI revealed high intensities on T (2)-weighted imaging and marked reductions of water diffusion in the white matter of the bilateral centrum semiovale and the corpus callosum. These abnormalities disappeared along with the neurological symptoms within a week in both patients. These children represent a characteristic group of patients among childhood acute encephalopathy.


Subject(s)
Brain Diseases/pathology , Corpus Callosum/pathology , Acute Disease , Atrophy , Brain Diseases/drug therapy , Child , Diffusion Magnetic Resonance Imaging/methods , Female , Humans , Image Processing, Computer-Assisted/methods , Immunoglobulins, Intravenous/therapeutic use , Magnetic Resonance Imaging/methods , Male , Nerve Tissue/pathology
12.
J Chem Phys ; 121(17): 8589-93, 2004 Nov 01.
Article in English | MEDLINE | ID: mdl-15511184

ABSTRACT

The interaction of HCl with the D(2)O-ice surface has been investigated in the temperature range 15-200 K by utilizing time-of-flight secondary ion mass spectroscopy, temperature-programmed desorption, and x-ray photoelectron spectroscopy. The intensities of sputtered H(+)(D(2)O) and Cl(-) ions (the H(+) ions) are increased (decreased) markedly above 40 K due to the hydrogen bond formation between the HCl and D(2)O molecules. The HCl molecules which form ionic hydrates undergo H/D exchange at 110-140 K and a considerable fraction of them dissolves into the bulk above 140 K. The neutral hydrates of HCl should coexist as evidenced by the desorption of HCl above 170 K. They are incorporated completely in the D(2)O layer up to 140 K. The HCl molecules embedded in the thick D(2)O layer dissolve into the bulk, and the ionic hydrate tends to segregate to the surface above 150 K.

13.
J Chem Phys ; 120(12): 5723-8, 2004 Mar 22.
Article in English | MEDLINE | ID: mdl-15267450

ABSTRACT

TOF-SIMS is used to investigate the interactions between D2O and hydrophobic molecules, such as CH4, CH3F, CH2F2, CHF3, and CF4, at cryogenic temperatures (15 K). By irradiation with a 1.5-keV He+ beam, the D(+)(D2O)n ions are ejected efficiently from the D2O nanoclusters physisorbed on the CF4 layer due to Coulomb explosion: the ion yields are by about two orders of magnitude higher than those from a thick D2O layer via the kinetic sputtering. The D(+)(D2O)n yields decrease on the CHnF(4-n) layer with increasing the number of the C-H group. This is because the Coulombic fission is quenched due to the delocalization of valence holes through the C-H...H-C and C-H...D2O contacts. A pure D2O film is hardly grown on the CH4 layer as a consequence of intermixing whereas the D2O molecules basically adsorb on the surfaces of fluoromethanes, suggesting the attractive (water-repellent) interactions in the C-H...D2O (C-F...D2O) contacts. The C-H...O bond behaves like a conventional O-H...O hydrogen bond as far as the collision-induced proton transfer reaction is concerned.

14.
Diabetologia ; 47(5): 794-805, 2004 May.
Article in English | MEDLINE | ID: mdl-15127200

ABSTRACT

AIMS/HYPOTHESIS: Oxidative stress is associated with diabetes, hypertension and atherosclerosis. Insulin resistance is implicated in the development of these disorders. We tested the hypothesis that oxidative stress induces insulin resistance in rats, and endeavoured to identify mechanisms linking the two. METHODS: Buthionine sulfoximine (BSO), an inhibitor of glutathione synthase, was administered to Sprague-Dawley rats and 3T3-L1 adipocytes. Glucose metabolism and insulin signalling both in vivo and in 3T3-L1 adipocytes were examined. In 3T3-L1 adipocytes, the effects of overexpression of a dominant negative mutant of inhibitory kappa B (I kappa B), one role of which is to block oxidative-stress-induced nuclear factor (NF)-kappa B activation, were investigated. RESULTS: In rats given BSO for 2 weeks, the plasma lipid hydroperoxide level doubled, indicating increased oxidative stress. A hyperinsulinaemic-euglycaemic clamp study and a glucose transport assay using isolated muscle and adipocytes revealed insulin resistance in BSO-treated rats. BSO treatment also impaired insulin-induced glucose uptake and GLUT4 translocation in 3T3-L1 adipocytes. In BSO-treated rat muscle, adipose tissue and 3T3-L1 adipocytes, insulin-induced IRS-1 phosphorylation in the low-density microsome (LDM) fraction was specifically decreased, while that in whole cell lysates was not altered, and subsequent translocation of phosphatidylinositol (PI) 3-kinase from the cytosol and the LDM fraction was disrupted. BSO-induced impairments of insulin action and insulin signalling were reversed by overexpressing the dominant negative mutant of I kappa B, thereby suppressing NF-kappa B activation. CONCLUSIONS/INTERPRETATION: Oxidative stress induces insulin resistance by impairing IRS-1 phosphorylation and PI 3-kinase activation in the LDM fraction, and NF-kappa B activation is likely to be involved in this process.


Subject(s)
Insulin Resistance/physiology , NF-kappa B/metabolism , Oxidative Stress/physiology , Phosphatidylinositol 3-Kinases/metabolism , 3T3 Cells , Adipocytes/metabolism , Animals , Biological Transport , Blood Glucose/drug effects , Blood Glucose/metabolism , Glucose/metabolism , Glucose Clamp Technique , Hyperinsulinism/blood , In Vitro Techniques , Infusions, Intravenous , Insulin/administration & dosage , Insulin/pharmacology , Insulin Receptor Substrate Proteins , Male , Mice , Muscle, Skeletal/metabolism , Phosphoproteins/metabolism , Phosphorylation , Rats , Rats, Sprague-Dawley
15.
Cell Death Differ ; 11(7): 771-81, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15031724

ABSTRACT

Bcl-2 homology domain (BH) 3-only proteins of the proapoptotic Bcl-2 subfamily play a key role as initiators of mitochondria-dependent apoptosis. To date, at least 10 mammalian BH3-only proteins have been identified, and it is now being realized that they have different roles and mechanisms of regulation in the transduction of apoptotic signals to mitochondria. Hrk/DP5 is one of the mammalian BH3-only proteins implicated in a variety of physiological and pathological apoptosis, yet the molecular mechanism involved in Hrk-mediated apoptosis remains poorly understood. In an attempt to identify cellular proteins participating in Hrk-mediated apoptosis, we have conducted yeast two-hybrid screening for Hrk-interacting proteins and isolated p32, a mitochondrial protein that has been shown to form a channel consisting of its homotrimer. In vitro binding, co-immunoprecipitation, as well as immunocytochemical analyses verified specific interaction and colocalization of Hrk and p32, both of which depended on the presence of the highly conserved C-terminal region of p32. Importantly, Hrk-induced apoptosis was suppressed by the expression of p32 mutants lacking the N-terminal mitochondrial signal sequence (p32(74-282)) and the conserved C-terminal region (p32 (1-221)), which are expected to inhibit binding of Hrk competitively to the endogenous p32 protein and to disrupt the channel function of p32, respectively. Furthermore, small interfering RNA-mediated knockdown of p32 conferred protection against Hrk-induced apoptosis. Altogether, these results suggest that p32 may be a key molecule that links Hrk to mitochondria and is critically involved in the regulation of Hrk-mediated apoptosis.


Subject(s)
Mitochondrial Proteins/metabolism , Neuropeptides/metabolism , Nuclear Proteins/metabolism , Peptide Fragments/metabolism , Proto-Oncogene Proteins/metabolism , Amino Acid Sequence , Animals , Apoptosis , Apoptosis Regulatory Proteins , Astrocytoma/pathology , Binding Sites , COS Cells , Carrier Proteins , Cell Line, Tumor , Chlorocebus aethiops , Conserved Sequence , Fluorescein-5-isothiocyanate , Fluorescent Dyes , Glutathione Transferase/metabolism , Humans , Immunohistochemistry , Microscopy, Fluorescence , Nuclear Proteins/chemistry , Nuclear Proteins/genetics , Nuclear Proteins/isolation & purification , Precipitin Tests , Protein Binding , RNA, Small Interfering/metabolism , Recombinant Fusion Proteins/metabolism , Rhodamines , Sequence Deletion , Two-Hybrid System Techniques
16.
Int Immunopharmacol ; 4(1): 149-56, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14975369

ABSTRACT

The enzyme-linked immunospot (ELISPOT) assay is an efficient technique for the enumeration of single cells secreting antibodies and cytokines. For simultaneous differentiation of individual cells producing interleukin-2 (IL-2) and interleukin-4 (IL-4) at a single cell level in human peripheral blood mononuclear cells (PBMCs), a human dual-color ELISPOT assay has been optimized. In the present system, the red spots corresponding to IL-2-secreting cells (T helper type 1, Th1, cells) were developed with horseradish peroxidase and the amino ethyl carbazole (AEC)/H2O2. The blue spots corresponding to IL-4-secreting cells (T helper type 2, Th2, cells) were developed with an alkaline phosphatase and the Vector blue. The usefulness of the assay method was tested. With this system, we could detect the IL-2- and IL-4-secreting cells simultaneously in human PBMCs of a juvenile rheumatoid arthritis (JRA) patient. This procedure provides useful information on clinical immune disorders.


Subject(s)
Enzyme-Linked Immunosorbent Assay , Interleukin-2/analysis , Interleukin-4/analysis , Adult , Arthritis, Juvenile/immunology , Child, Preschool , Female , Humans , Interleukin-2/metabolism , Interleukin-4/metabolism , Male , Sensitivity and Specificity , Th1 Cells/metabolism , Th2 Cells/metabolism
17.
Curr Biol ; 11(24): 1958-62, 2001 Dec 11.
Article in English | MEDLINE | ID: mdl-11747822

ABSTRACT

Growth factors promote cell survival and cell motility, presumably through the activation of Akt and the Rac and Cdc42 GTPases, respectively. Because Akt is dispensable for Rac/Cdc42 regulation of actin reorganization, it has been assumed that Rac and Cdc42 stimulate cell motility independent of Akt in mammalian cells. However, in this study we demonstrate that Akt is essential for Rac/Cdc42-regulated cell motility in mammalian fibroblasts. A dominant-negative Akt inhibits cell motility stimulated by Rac/Cdc42 or by PDGF treatment, without affecting ruffling membrane-type actin reorganization. We have confirmed a previous report that Akt is activated by expression of Rac and Cdc42 and also observed colocalization of endogenous phosphorylated Akt with Rac and Cdc42 at the leading edge of fibroblasts. Importantly, expression of active Akt but not the closely related kinase SGK is sufficient for increasing cell motility. This effect of Akt is cell autonomous and not mediated by inhibition of GSK3. Finally, we found that dominant-negative Akt but not SGK reverses the increased cell motility phenotype of fibroblasts lacking the PTEN tumor suppressor gene. Taken together, these results suggest that Akt promotes cell motility downstream of Rac/Cdc42 in growth factor-stimulated cells and in invasive PTEN-deficient cells.


Subject(s)
Cell Movement/physiology , Growth Substances/physiology , Phosphoric Monoester Hydrolases/physiology , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/physiology , Tumor Suppressor Proteins/physiology , cdc42 GTP-Binding Protein/physiology , rac GTP-Binding Proteins/physiology , Animals , Dictyostelium , PTEN Phosphohydrolase , Phosphoric Monoester Hydrolases/genetics , Proto-Oncogene Proteins c-akt , Tumor Suppressor Proteins/genetics
18.
J Neurosci ; 21(19): 7551-60, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11567045

ABSTRACT

Elevated levels of beta-Amyloid (Abeta) are present in the brains of individuals with either the sporadic or familial form of Alzheimer's disease (AD), and the deposition of Abeta within the senile plaques that are a hallmark of AD is thought to be a primary cause of the cognitive dysfunction that occurs in AD. Recent evidence suggests that Abeta induces neuronal apoptosis in the brain and in primary neuronal cultures, and that this Abeta-induced neuronal death may be responsible in part for the cognitive decline found in AD patients. In this study we have characterized one mechanism by which Abeta induces neuronal death. We found that in cortical neurons exposed to Abeta, activated c-Jun N-terminal kinase (JNK) is required for the phosphorylation and activation of the c-Jun transcription factor, which in turn stimulates the transcription of several key target genes, including the death inducer Fas ligand. The binding of Fas ligand to its receptor Fas then induces a cascade of events that lead to caspase activation and ultimately cell death. By analyzing the effects of mutations in each of the components of the JNK-c-Jun-Fas ligand-Fas pathway, we demonstrate that this pathway plays a critical role in mediating Abeta-induced death of cultured neurons. These findings raise the possibility that the JNK pathway may also contribute to Abeta-dependent death in AD patients.


Subject(s)
Alzheimer Disease/metabolism , Amyloid beta-Peptides/pharmacology , Apoptosis , Membrane Glycoproteins/metabolism , Mitogen-Activated Protein Kinases/metabolism , Neurons/drug effects , Alzheimer Disease/etiology , Animals , Apoptosis/genetics , Cells, Cultured , Enzyme Activation/drug effects , Fas Ligand Protein , Gene Expression Regulation , JNK Mitogen-Activated Protein Kinases , Membrane Glycoproteins/genetics , Mice , Mice, Inbred Strains , Mice, Knockout , Mitogen-Activated Protein Kinase 10 , Mitogen-Activated Protein Kinases/deficiency , Mitogen-Activated Protein Kinases/genetics , Neurons/metabolism , Neurons/pathology , Phosphorylation/drug effects , Protein-Tyrosine Kinases/deficiency , Protein-Tyrosine Kinases/genetics , Proto-Oncogene Proteins c-jun/metabolism , Rats , Rats, Long-Evans , Signal Transduction/drug effects , Transcription, Genetic/drug effects , fas Receptor/metabolism
19.
J Gastroenterol ; 36(7): 492-4, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11480794

ABSTRACT

PURPOSE: Because biopsy forceps tend to turn towards the right hepatic duct during endoscopic retrograde cholangiopancreatography (ERCP), selective access to the left hepatic duct is difficult. METHODS: In this study, we managed to insert biopsy forceps selectively into the left hepatic duct, by using a looping technique, in three patients. Biopsy forceps were inserted into the right hepatic duct by the conventional method. The elevator of the endoscope was kept down, and the shaft of the biopsy forceps was then advanced to the duodenal cavity until it formed a loop between the endoscope and the papilla. During the procedure, the tip of the forceps was kept at the hepatic hilus. RESULTS: In this condition, we were able to slowly rotate the tip of the forceps and direct the forceps towards the left. Sufficient material from the left hepatic duct was obtained in all patients. CONCLUSIONS: The looping technique was useful for selective access to the left hepatic duct.


Subject(s)
Bile Duct Neoplasms/pathology , Biopsy/methods , Cholangiopancreatography, Endoscopic Retrograde , Adult , Aged , Bile Duct Neoplasms/diagnostic imaging , Biopsy/instrumentation , Female , Humans , Male , Middle Aged
20.
Proc Natl Acad Sci U S A ; 98(18): 10148-53, 2001 Aug 28.
Article in English | MEDLINE | ID: mdl-11517310

ABSTRACT

MST1, mammalian STE20-like kinase 1, is a serine/threonine kinase that is cleaved and activated by caspases during apoptosis. MST1 is capable of inducing apoptotic morphological changes such as chromatin condensation upon overexpression. In this study, we show that MST1 contains two functional nuclear export signals (NESs) in the C-terminal domain, which is released from the N-terminal kinase domain upon caspase-mediated cleavage. Full-length MST1 is excluded from the nucleus and localized to the cytoplasm. However, either truncation of the C-terminal domain, point mutation of the two putative NESs, or treatment with leptomycin B, an inhibitor of the NES receptor, results in nuclear localization of MST1. Staurosporine treatment induces chromatin condensation, MST1 cleavage, and nuclear translocation. Staurosporine-induced chromatin condensation is partially inhibited by expressing a kinase-negative mutant of MST1, suggesting an important role of MST1 in this process. Significantly, MST1 is more efficient at inducing chromatin condensation when it is constitutively localized to the nucleus by mutation of its NESs. Moreover, inhibition of MST1 nuclear translocation by mutation of its cleavage sites reduces its ability to induce chromatin condensation. Taken together, these results suggest that truncation of the C-terminal domain of MST1 by caspases may result in translocation of MST1 into the nucleus, where it promotes chromatin condensation.


Subject(s)
Caspases/metabolism , Chromatin/metabolism , Protein Serine-Threonine Kinases/metabolism , Active Transport, Cell Nucleus , Amino Acid Sequence , Animals , Apoptosis , Base Sequence , COS Cells , Cell Line , Cell Nucleus/enzymology , Chromatin/drug effects , DNA Primers/genetics , Humans , Intracellular Signaling Peptides and Proteins , Mutation , Protein Serine-Threonine Kinases/genetics , Staurosporine/pharmacology , Transfection
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