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1.
Am J Physiol Regul Integr Comp Physiol ; 311(1): R200-8, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27170658

RESUMO

Hepatic glucose production (HGP) normally begins just prior to birth. Prolonged fetal hypoglycemia, intrauterine growth restriction, and acute hypoxemia produce an early activation of fetal HGP. To test the hypothesis that prolonged hypoxemia increases factors which regulate HGP, studies were performed in fetuses that were bled to anemic conditions (anemic: n = 11) for 8.9 ± 0.4 days and compared with control fetuses (n = 7). Fetal arterial hematocrit and oxygen content were 32% and 50% lower, respectively, in anemic vs. controls (P < 0.005). Arterial plasma glucose was 15% higher in the anemic group (P < 0.05). Hepatic mRNA expression of phosphonenolpyruvate carboxykinase (PCK1) was twofold higher in the anemic group (P < 0.05). Arterial plasma glucagon concentrations were 70% higher in anemic fetuses compared with controls (P < 0.05), and they were positively associated with hepatic PCK1 mRNA expression (P < 0.05). Arterial plasma cortisol concentrations increased 90% in the anemic fetuses (P < 0.05), but fetal cortisol concentrations were not correlated with hepatic PCK1 mRNA expression. Hepatic glycogen content was 30% lower in anemic vs. control fetuses (P < 0.05) and was inversely correlated with fetal arterial plasma glucagon concentrations. In isolated primary fetal sheep hepatocytes, incubation in low oxygen (3%) increased PCK1 mRNA threefold compared with incubation in normal oxygen (21%). Together, these results demonstrate that glucagon and PCK1 may potentiate fetal HGP during chronic fetal anemic hypoxemia.


Assuntos
Anemia/metabolismo , Hipóxia Fetal/metabolismo , Feto/metabolismo , Glucagon/sangue , Hipóxia/metabolismo , Fígado/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , RNA Mensageiro/genética , Animais , Feminino , Glucose-6-Fosfatase/metabolismo , Glicogênio/metabolismo , Hepatócitos/metabolismo , Hidrocortisona/sangue , Tamanho do Órgão , Gravidez , RNA Mensageiro/biossíntese , Ovinos , Cordão Umbilical
2.
Am J Physiol Regul Integr Comp Physiol ; 309(8): R920-8, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26224688

RESUMO

Intrauterine growth-restricted (IUGR) fetal sheep, produced by placental insufficiency, have lower oxygen concentrations, higher lactate concentrations, and increased hepatic glucose production that is resistant to suppression by insulin. We hypothesized that increased lactate production in the IUGR fetus results from reduced glucose oxidation, during basal and maximal insulin-stimulated conditions, and is used to support glucose production. To test this, studies were performed in late-gestation control (CON) and IUGR fetal sheep under basal and hyperinsulinemic-clamp conditions. The basal glucose oxidation rate was similar and increased by 30-40% during insulin clamp in CON and IUGR fetuses (P < 0.005). However, the fraction of glucose oxidized was 15% lower in IUGR fetuses during basal and insulin-clamp periods (P = 0.05). IUGR fetuses also had four-fold higher lactate concentrations (P < 0.001) and lower lactate uptake rates (P < 0.05). In IUGR fetal muscle and liver, mRNA expression of pyruvate dehydrogenase kinase (PDK4), an inhibitor of glucose oxidation, was increased over fourfold. In IUGR fetal liver, but not skeletal muscle, mRNA expression of lactate dehydrogenase A (LDHA) was increased nearly fivefold. Hepatic expression of the gluconeogenic genes, phosphoenolpyruvate carboxykinase (PCK)1, and PCK2, was correlated with expression of PDK4 and LDHA. Collectively, these in vivo and tissue data support limited capacity for glucose oxidation in the IUGR fetus via increased PDK4 in skeletal muscle and liver. We speculate that lactate production also is increased, which may supply carbon for glucose production in the IUGR fetal liver.


Assuntos
Retardo do Crescimento Fetal/veterinária , Feto/metabolismo , Glucose/metabolismo , Animais , Feminino , Regulação da Expressão Gênica , Gluconeogênese/fisiologia , Técnica Clamp de Glucose , Insulina/metabolismo , Insulina/farmacologia , Lactatos/metabolismo , Fígado/metabolismo , Masculino , Oxirredução , Gravidez , Ovinos
3.
J Pers Soc Psychol ; 93(4): 565-82, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17892332

RESUMO

Unfavorable evaluations of others reflect both specific prejudice and generalized negativity. Study 1 examined self-reported norms and personal endorsement of prejudices to various social groups. Study 2 used judgments of overweight persons to examine links among prejudice, personality, and prosocial motives. Study 3 examined negative evaluations and social distancing during interpersonal interaction. Study 4 observed the translation of negative evaluations into overt discrimination. Study 5 experimentally manipulated the behavior of the target and observed its interactive effects with weight, personality, and prosocial motives. Results suggest that prejudice can emerge from otherwise unprejudiced persons when situations permit justification. Patterns in negative evaluations are linked distinctively to (a) the Big Five dimension of Agreeableness, (b) proximal social cognition and motives, and (c) discrimination.


Assuntos
Afeto , Relações Interpessoais , Personalidade , Preconceito , Adulto , Cultura , Feminino , Humanos , Masculino , Obesidade/psicologia , Distância Psicológica , Comportamento Social , Conformidade Social , Desejabilidade Social , Valores Sociais , Estereotipagem
4.
J Neurosci ; 23(33): 10662-71, 2003 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-14627651

RESUMO

Several human neurodegenerative diseases are associated with abnormal accumulations of aggregated tau proteins and glial degeneration in astrocytes, but the mechanism whereby tau proteins cause astrocytic degeneration is unclear. Here, we analyzed the biological consequences of overexpressing the longest human tau isoform in primary cultures of rat astrocytes using adenoviral-mediated gene transfer. Significantly, we found specific decreases in stable detyrosinated [glutamate (Glu)] microtubules (MTs) with concomitant increases in tubulin biosynthesis and the accumulation of acetylated, tyrosinated, alpha- and beta-tubulin. The consequences of this selective reduction in stable Glu-MTs included contemporaneous decreases in kinesin levels, collapse of the intermediate filament network, progressive disruption of kinesin-dependent trafficking of organelles, fragmentation of the Golgi apparatus that culminated in atrophy, and non-apoptotic death of astrocytes. These results suggest that reduced stable Glu-MTs is a primary consequence of tau accumulation that initiates mechanisms underlying astrocyte dysfunction and death in human neurodegenerative glial tauopathies.


Assuntos
Astrócitos/metabolismo , Complexo de Golgi/metabolismo , Microtúbulos/metabolismo , Tirosina/metabolismo , Proteínas tau/farmacologia , Acetilação , Adenoviridae/genética , Animais , Astrócitos/patologia , Morte Celular , Células Cultivadas , Técnicas de Transferência de Genes , Complexo de Golgi/patologia , Humanos , Filamentos Intermediários/patologia , Cinesinas/metabolismo , Microtúbulos/patologia , Organelas/patologia , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Isoformas de Proteínas/farmacologia , Transporte Proteico/efeitos dos fármacos , Ratos , Tauopatias/etiologia , Tauopatias/metabolismo , Tubulina (Proteína)/metabolismo , Proteínas tau/biossíntese , Proteínas tau/genética
5.
Gene ; 332: 97-106, 2004 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-15145059

RESUMO

A cDNA encoding feline granulocyte-macrophage colony stimulating factor was cloned from alveolar macrophages using the reverse transcriptase-polymerase chain reaction (RT-PCR). The cDNA is 426 bp in length and encodes a predicted mature protein of 127 amino acids and the majority of the signal peptide. The recombinant protein (rfGM-CSF) was expressed in both Escherichia coli, as a calmodulin fusion protein, and mammalian cells. Biological activity of both recombinant proteins was demonstrated using the human erythroleukaemic cell line, TF-1. In a soft agar clonogenic assay, rfGM-CSF supported the development of granulocyte, macrophage and granulocyte-macrophage colonies. In combination with phytohaemagglutin (PHA) lymphocyte-conditioned medium, the number and size of such colonies were increased. Culture of feline bone marrow cells with rfGM-CSF was an efficient method for producing cells with morphology typical of dendritic cells (DC). The availability of the recombinant cytokine will permit further studies, in particular, the evaluation of the role of dendritic cells in feline immunopathology and its potential as a vaccine adjuvant.


Assuntos
Gatos/genética , DNA Complementar/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células CHO , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Clonagem Molecular , Cricetinae , Cricetulus , DNA Complementar/química , DNA Complementar/isolamento & purificação , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Timidina/metabolismo
6.
Clin Ther ; 34(3): 699-709, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22336488

RESUMO

BACKGROUND: Bioavailability of the tablet formulation of eltrombopag, an oral thrombopoietin receptor agonist indicated for the treatment of chronic immune thrombocytopenia, is reduced by chelation of polyvalent cations (eg, calcium). A powder for oral suspension (PfOS) formulation has been developed for use in pediatrics. OBJECTIVE: We aimed to assess the bioavailability of eltrombopag PfOS relative to the tablet formulation and the effect of a high-calcium meal on PfOS bioavailability. METHODS: In this single-dose, open-label, randomized-sequence, crossover study, healthy subjects received 25 mg eltrombopag orally as a tablet fasted and as PfOS fasted or with, 2 hours before, or 2 hours after a high-calcium meal. Noncompartmental pharmacokinetic parameters were estimated from plasma concentration-time data collected over 72 hours post-dose. Tolerability was assessed by laboratory tests, physical examinations, and adverse events (AEs). RESULTS: The 40 enrolled subjects included 22 males and 18 females of white/European (60%) or African-American/African (40%) heritage with mean (SD) (mininum, maximum) age of 34 (12) (19, 62) years, weight of 75 (12) (54, 101) kg, and body mass index of 25.8 (2.9) (19.7, 30) kg/m(2). Plasma eltrombopag AUC(0-∞) was higher for the PfOS than the tablet (geometric least-squares mean ratio [GMR]: 1.22; 90% CI: 1.08-1.38). Plasma eltrombopag AUC(0-∞) was reduced when the PfOS was administered with a high-calcium meal (GMR: 0.25; 90% CI: 0.224-0.287) or 2 hours after a meal (GMR: 0.53; 90% CI: 0.470-0.601), and, to a lesser extent, when administered 2 hours before a meal (GMR: 0.80; 90% CI: 0.711-0.908). The absorption lag time and t(½) did not differ between treatments; T(max) was delayed 1 hour when the PfOS was dosed with a high-calcium meal. AEs were not serious and mild or moderate in intensity. AEs reported in >1 subject included headache (11 subjects; 27.5%), presyncope (3 subjects, 7.5%), and vomiting (2 subjects, 5%). No clinically significant trends in laboratory tests or vital signs were observed. CONCLUSIONS: In a healthy adult volunteer population, bioavailability of eltrombopag PfOS was greater than the tablet and was reduced when administered with or 2 hours before or after a high-calcium meal; this effect was attenuated with PfOS dosing 2 hours before the meal. Eltrombopag was generally well tolerated.


Assuntos
Benzoatos/farmacocinética , Cálcio/metabolismo , Interações Alimento-Droga , Alimentos , Hidrazinas/farmacocinética , Pirazóis/farmacocinética , Administração Oral , Adolescente , Adulto , Benzoatos/administração & dosagem , Benzoatos/sangue , Benzoatos/farmacologia , Disponibilidade Biológica , Estudos Cross-Over , Feminino , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/sangue , Hidrazinas/farmacologia , Masculino , Pessoa de Meia-Idade , Pós , Pirazóis/administração & dosagem , Pirazóis/sangue , Pirazóis/farmacologia , Receptores de Trombopoetina/agonistas , Suspensões , Comprimidos , Fatores de Tempo , Adulto Jovem
7.
ACS Appl Mater Interfaces ; 1(2): 279-88, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20353215

RESUMO

The generation and characterization of a robust thienylsilane molecular layer on indium tin oxide substrates was investigated. The molecular layer was found to reduce the oxidation potential required for the electrochemical polymerization of 3,4-ethylenedioxythiophene. The resulting electrochemically prepared poly(3,4-ethylenedioxythiophene):poly(p-styrenesulfonate) (ePEDOT:PSS) films were found to be more uniform in coverage with lower roughness and higher conductivity than analogous films fabricated with bare ITO. A relative improvement in the efficiency of 2,5-diyl-poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) bulk heterojunction solar cells was observed when devices were formed on thienylsilane-modified ITO electrodes, rather than unmodified ITO control electrodes.

8.
Vaccine ; 24(49-50): 7095-108, 2006 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17049683

RESUMO

Protection against feline immunodeficiency virus (FIV) has been achieved using a variety of vaccines notably whole inactivated virus (WIV) and DNA. However protection against more virulent isolates, typical of those encountered in natural infections, has been difficult to achieve. In an attempt to improve protection against virulent FIV(GL8), we combined both DNA and WIV vaccines in a "prime-boost" approach. Thirty cats were divided into four groups receiving vaccinations and one unvaccinated control group. Following viral challenge, two vaccinated animals, one receiving DNA alone and one the prime-boost vaccine remained free of viraemia, whilst all controls became viraemic. Animals vaccinated with WIV showed apparent early enhancement of infection at 2 weeks post challenge (pc) with higher plasma viral RNA loads than control animals or cats immunised with DNA alone. Despite this, animals vaccinated with WIV or DNA alone showed significantly lower proviral loads in peripheral blood mononuclear cells and mesenteric lymph node cells, whilst those receiving the DNA-WIV prime-boost vaccine showed significantly lower proviral loads in PBMC, than control animals, at 35 weeks pc. Therefore both DNA and WIV vaccines conferred limited protection against viral challenge but the combination of WIV and DNA in a prime-boost approach appeared to offer no significant advantage over either vaccine alone.


Assuntos
Síndrome de Imunodeficiência Adquirida Felina/imunologia , Síndrome de Imunodeficiência Adquirida Felina/prevenção & controle , Vírus da Imunodeficiência Felina/imunologia , Vacinas Virais/uso terapêutico , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/biossíntese , Gatos , Ensaio de Imunoadsorção Enzimática , Imunidade Celular/imunologia , Esquemas de Imunização , Imunização Secundária , Integrases/genética , Integrases/imunologia , Interferon gama/metabolismo , Linfonodos/virologia , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/virologia , RNA Viral/sangue , Baço/virologia , Vacinas de DNA/imunologia , Vacinas de Produtos Inativados/imunologia , Carga Viral , Viremia/imunologia , Viremia/virologia
9.
Am J Pathol ; 169(4): 1343-52, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17003490

RESUMO

Frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) is a common neuropathological subtype of frontotemporal dementia. Although this subtype of frontotemporal dementia is defined by the presence of ubiquitin-positive but tau- and alpha-synuclein-negative inclusions, it is unclear whether all cases of FTLD-U have the same underlying pathogenesis. Examination of tissue sections from FTLD-U brains stained with anti-ubiquitin antibodies revealed heterogeneity in the morphological characteristics of pathological inclusions among subsets of cases. Three types of FTLD-U were delineated based on morphology and distribution of ubiquitin-positive inclusions. To address the hypothesis that FTLD-U is pathologically heterogeneous, novel monoclonal antibodies (mAbs) were generated by immunization of mice with high molecular mass (Mr > 250 kd) insoluble material prepared by biochemical fractionation of FTLD-U brains. Novel mAbs were identified that immunolabeled all of the ubiquitin-positive inclusions in one subset of FTLD-U cases, whereas other mAbs stained the ubiquitin-positive inclusions in a second subset of cases. These novel mAbs did not stain inclusions in other neurodegenerative disorders, including tauopathies and alpha-synucleinopathies. Therefore, ubiquitin immunohistochemistry and the immunostaining properties of the novel mAbs generated here suggest that FTLD-U is pathologically heterogeneous. Identification of the disease proteins recognized by these mAbs will further advance understanding of molecular substrates of FTLD-U neurodegenerative pathways.


Assuntos
Anticorpos Monoclonais/imunologia , Demência/patologia , Lobo Frontal/patologia , Corpos de Inclusão/química , Lobo Temporal/patologia , Ubiquitina/análise , Idoso , Animais , Anticorpos Monoclonais/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade , Ubiquitina/imunologia
10.
Science ; 314(5796): 130-3, 2006 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-17023659

RESUMO

Ubiquitin-positive, tau- and alpha-synuclein-negative inclusions are hallmarks of frontotemporal lobar degeneration with ubiquitin-positive inclusions and amyotrophic lateral sclerosis. Although the identity of the ubiquitinated protein specific to either disorder was unknown, we showed that TDP-43 is the major disease protein in both disorders. Pathologic TDP-43 was hyper-phosphorylated, ubiquitinated, and cleaved to generate C-terminal fragments and was recovered only from affected central nervous system regions, including hippocampus, neocortex, and spinal cord. TDP-43 represents the common pathologic substrate linking these neurodegenerative disorders.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Química Encefálica , Proteínas de Ligação a DNA/análise , Demência/metabolismo , Medula Espinal/química , Ubiquitina/análise , Sequência de Aminoácidos , Esclerose Lateral Amiotrófica/patologia , Anticorpos Monoclonais , Córtex Cerebral/química , Córtex Cerebral/patologia , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Demência/genética , Demência/patologia , Imunofluorescência , Hipocampo/química , Hipocampo/patologia , Humanos , Immunoblotting , Dados de Sequência Molecular , Neurônios Motores/química , Neurônios Motores/patologia , Neurônios/química , Neurônios/patologia , Fragmentos de Peptídeos/química , Fosforilação , Medula Espinal/patologia
11.
Proc Natl Acad Sci U S A ; 102(1): 227-31, 2005 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-15615853

RESUMO

We tested the hypothesis that microtubule (MT)-binding drugs could be therapeutically beneficial in tauopathies by functionally substituting for the MT-binding protein tau, which is sequestered into inclusions of human tauopathies and transgenic mouse models thereof. Transgenic mice were treated for 12 weeks with weekly i.p. injections of 10 or 25 mg/m(2) paclitaxel (Paxceed). Both doses restored fast axonal transport in spinal axons, wherein MT numbers and stable (detyrosinated) tubulins were increased, compared with sham treatment, and only Paxceed ameliorated motor impairments in tau transgenic mice. Thus, MT-stabilizing drugs could have therapeutic potential for treating neurodegenerative tauopathies by offsetting losses of tau function that result from the sequestration of this MT-stabilizing protein into filamentous inclusions.


Assuntos
Axônios/metabolismo , Microtúbulos/efeitos dos fármacos , Proteínas tau/metabolismo , Animais , Antineoplásicos Fitogênicos , Axônios/efeitos dos fármacos , Axônios/patologia , Camundongos , Camundongos Transgênicos , Microtúbulos/metabolismo , Paclitaxel/farmacologia , Medula Espinal/efeitos dos fármacos , Proteínas tau/genética
12.
Vaccine ; 20(11-12): 1483-96, 2002 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-11858854

RESUMO

A molecular clone of the Glasgow-8 isolate of FIV (FIVGL8) was rendered replication defective by an in-frame deletion in either reverse transcriptase (deltaRT) or integrase (deltaIN) genes for use as DNA vaccines. To test the ability of these multi-gene vaccines to protect against two feline immunodeficiency virus (FIV) isolates of differing virulence, cats were immunized using either DNA vaccine alone or co-administered with interleukin-12 (IL-12) and/or interleukin-18 (IL-18) cytokine DNA. Animals were challenged sequentially with FIV-Petaluma (FIVPET) an FIV isolate of relatively low virulence and subsequently with the more virulent FIVGL8. A proportion of vaccinates (5/18 deltaIN and 2/12 deltaRT) were protected against primary challenge with FIV(PET). Five of the vaccinated-protected cats were re-challenged with FIV(PET); four (all deltaIN) remained free of viraemia whilst all naive controls became viraemic. Following subsequent challenge with the more virulent FIVGL8 these four vaccinated-protected animals all became viraemic but showed lower proviral loads than naive cats. This study suggests that while our current DNA vaccines may not produce sterilizing immunity against more virulent isolates of FIV, they may nevertheless significantly reduce the impact of infection.


Assuntos
Síndrome de Imunodeficiência Adquirida Felina/prevenção & controle , Vírus da Imunodeficiência Felina/imunologia , Vacinas de DNA/farmacologia , Vacinas Virais/farmacologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/biossíntese , Sequência de Bases , Gatos , DNA Viral/genética , Vírus Defeituosos/enzimologia , Vírus Defeituosos/genética , Vírus Defeituosos/imunologia , Síndrome de Imunodeficiência Adquirida Felina/imunologia , Genes Virais , Vírus da Imunodeficiência Felina/enzimologia , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/patogenicidade , Integrases/genética , Interleucina-12/administração & dosagem , Interleucina-18/administração & dosagem , Dados de Sequência Molecular , Provírus/isolamento & purificação , DNA Polimerase Dirigida por RNA/genética , Deleção de Sequência , Linfócitos T Citotóxicos/imunologia , Vacinas de DNA/administração & dosagem , Vacinas Virais/administração & dosagem , Virulência , Replicação Viral/genética
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