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1.
Clin Pract Cases Emerg Med ; 5(3): 136-138, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34437030

RESUMO

INTRODUCTION: Recently, euglycemic diabetic ketoacidosis has been an increasing topic of discussion within emergency medicine literature. Euglycemic diabetic ketoacidosis can easily be missed, as a normal point-of-care glucose often mistakenly precludes the work-up of diabetic ketoacidosis. CASE REPORT: A 16-year-old female with a past medical history of type 1 diabetes presented to the emergency department with altered mental status, vomiting, and abdominal pain. She was diagnosed with euglycemic diabetic ketoacidosis. CONCLUSION: Reported cases of euglycemic diabetic ketoacidosis are most frequently attributed to sodium glucose cotransporter-2 inhibitors, but other potential causes have been discussed in the literature. In this patient, a starvation state with continued insulin use in the setting of acute appendicitis led to her condition.

2.
Bioorg Med Chem Lett ; 28(10): 1958-1963, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29653895

RESUMO

Hypothalamic CAMKK2 represents a potential mechanism for chemically affecting satiety and promoting weight loss in clinically obese patients. Single-digit nanomolar inhibitors of CAMKK2 were identified in three related ATP-competitive series. Limited optimization of kinase selectivity, solubility, and pharmacokinetic properties were undertaken on all three series, as SAR was often transferrable. Ultimately, a 2,4-diaryl 7-azaindole was optimized to afford a tool molecule that potently inhibits AMPK phosphorylation in a hypothalamus-derived cell line, is orally bioavailable, and crosses the blood-brain barrier. When dosed orally in rodents, compound 4 t limited ghrelin-induced food intake.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Administração Oral , Animais , Encéfalo/metabolismo , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/genética , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Grelina/farmacologia , Ligação de Hidrogênio , Indóis/química , Indóis/metabolismo , Concentração Inibidora 50 , Camundongos , Mutagênese , Inibidores de Proteínas Quinases/metabolismo
3.
Nanomedicine (Lond) ; 7(7): 1017-28, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22348271

RESUMO

BACKGROUND: Current thrombolytic therapies utilize exogenous plasminogen activators (PAs) to effectively lyse clots, restoring blood flow, and preventing tissue and organ death. These PAs may also impair normal hemostasis, leading to life-threatening bleeding, including intracerebral hemorrhage. AIMS: This study aims to develop new thrombus-targeted fibrinolytic agents that harness the multifunctional theranostic capabilities of nanomaterials, potentially allowing for the generation of efficacious thrombolytics while minimizing deleterious side effects. MATERIALS & METHODS: A thrombus-targeted nano-fibrinolytic agent was synthesized using a magnetofluorescent crosslinked dextran-coated iron oxide nanoparticle platform that was conjugated to recombinant tissue PA (tPA). Thrombus-targeting was achieved by derivatizing the nanoparticle with an activated factor XIII (FXIIIa)-sensitive peptide. Human plasma clot binding ability of the targeted and control agents was assessed by fluorescence reflectance imaging. Next, the in vitro enzymatic activity of the agents was assessed by S2288-based amidolytic activity, and an ELISA D-dimer assay for fibrinolysis. In vivo targeting of the nanoagent was next examined by intravital fluorescence microscopy of murine arterial and venous thrombosis. The fibrinolytic activity of the targeted nanoagent compared to free tPA was then evaluated in vivo in murine pulmonary embolism. RESULTS: In vitro, the targeted thrombolytic nanoagent demonstrated superior binding to fresh-frozen plasma clots compared to control nanoagents (analysis of variance, p < 0.05). When normalized by S2288-based amidolytic activity, targeted, control and free tPA samples demonstrated equivalent in vitro fibrinolytic activity against human plasma clots, as determined by ELISA D-dimer assays. The FXIIIa targeted fibrinolytic nanoagent efficiently bound the margin of intravascular thrombi as detected by intravital fluorescence microscopy. In in vivo fibrinolysis studies the FXIIIa-targeted agent lysed pulmonary emboli with similar efficacy as free tPA (p > 0.05). CONCLUSION: The applicability of a FXIIIa-targeted thrombolytic nanoagent in the treatment of thromboembolism was demonstrated in vitro and in vivo. Future studies are planned to investigate the safety profile and overall efficacy of this class of nanoagents.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Ativadores de Plasminogênio/administração & dosagem , Ativadores de Plasminogênio/uso terapêutico , Terapia Trombolítica/métodos , Trombose/tratamento farmacológico , Animais , Dextranos/química , Feminino , Compostos Férricos/química , Humanos , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/patologia , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/patologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Trombose/patologia , Veias/efeitos dos fármacos , Veias/patologia , Trombose Venosa/tratamento farmacológico , Trombose Venosa/patologia
4.
J Immunol ; 187(5): 2244-51, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21788441

RESUMO

Egress of lymphocytes from lymphoid tissues is a complex process in which Gαi-mediated signals play a decisive role. We show here that although FTY720, an agonist of the sphingosine 1-phosphate (S1P)(1) receptor, induces S1P(1) receptor internalization sufficiently in the presence or absence of Gαi2 or Gαi3, the drug blocks egress of wild-type (WT) and Gαi3-deficent T cells, but not Gαi2-deficient T cells, in both WT and Gαi2-deficient hosts. Intravital imaging of lymph nodes revealed that all three groups of T cells approached and engaged cortical sinusoids similarly in the presence or absence of FTY720. The cells also entered and departed the sinus at an almost identical frequency in the absence of the drug. However, after engagement of the sinus, most WT and Gαi3-deficient T cells retracted and migrated back into the parenchyma in FTY720-treated animals, due to a failure of the cells to establish adhesion on the sinus, whereas Gαi2-deficient T cells adhered firmly on the sinus, which prevented their retraction, facilitating their transmigration of the lymphatic endothelial barrier. These data confirm egress of Gαi2(-/-) T cells independent of S1P-mediated chemotaxis and failure of FTY720 to close lymphatic stromal channels and argue for the first time, to our knowledge, that FTY720 induces lymphopenia in part by impairing T cell adhesion to the sinus in a manner dependent on Gαi2.


Assuntos
Quimiotaxia de Leucócito/efeitos dos fármacos , Imunossupressores/farmacologia , Propilenoglicóis/farmacologia , Esfingosina/análogos & derivados , Linfócitos T/efeitos dos fármacos , Animais , Adesão Celular/efeitos dos fármacos , Adesão Celular/imunologia , Separação Celular , Quimiotaxia de Leucócito/imunologia , Cloridrato de Fingolimode , Citometria de Fluxo , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/imunologia , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Linfonodos/citologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Camundongos , Camundongos Knockout , Receptores de Lisoesfingolipídeo/agonistas , Esfingosina/farmacologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
5.
Eur J Immunol ; 38(7): 1988-98, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18521956

RESUMO

This study delineates specific functions of Galphai2 and Galphai3 in T cell mobilization during the development of graft-versus-host disease (GVHD) and reveals reciprocal effects of these two G proteins on the onset and morbidity of the disease. A deletion of Galphai2 hampered trafficking of pathogenic T cells from secondary lymphoid tissues to inflammatory sites and sufficiently prevented GVHD. In contrast, a severer disease was induced in mice adoptively transferred with Galphai3-deficient T cells than those mice transferred with wild-type T cells. In agreement with this, pathogenic Galphai2(-/-) T cells displayed a defect in response to CXCL10, CXCL11, and CCL5, whereas lack of Galphai3 augmented T effector cell chemotaxis induced by CXCL10 and CXCL11 and resulted in their preference of homing to the liver and colon. Absence of either Galphai also abrogated sphingosince-1-phosphate (S1P)-mediated inhibition of T cell chemokinesis and facilitated T cell homing and expansion in the spleen and mesenteric lymph nodes at the early phase of GVHD development, which is another key determinant in the severity and early onset of the disease in the mice infused with Galphai3(-/-) T cells. These observations underscore interplay between Galphai2 and Galphai3 and potentially provide a novel strategy to prevent GVHD by blocking T cell homing at early stages and T effector cell trafficking at later time points.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiocinas/metabolismo , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/metabolismo , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Quimiocinas/imunologia , Quimiotaxia de Leucócito , Colo/imunologia , Colo/patologia , Feminino , Fígado/imunologia , Fígado/patologia , Tecido Linfoide/imunologia , Lisofosfolipídeos/farmacologia , Camundongos , Camundongos Knockout , Camundongos SCID , Esfingosina/análogos & derivados , Esfingosina/farmacologia
6.
J Biol Chem ; 282(13): 9547-9555, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17289675

RESUMO

G protein-coupled receptors (GPCRs) convey extracellular stimulation into dynamic intracellular action, leading to the regulation of cell migration and differentiation. T lymphocytes express G alpha(i2) and G alpha(i3), two members of the G alpha(i/o) protein family, but whether these two G alpha(i) proteins have distinguishable roles guiding T cell migration remains largely unknown because of a lack of member-specific inhibitors. This study details distinct G alpha(i2) and G alpha(i3) effects on chemokine receptor CXCR3-mediated signaling. Our data showed that G alpha(i2) was indispensable for T cell responses to three CXCR3 ligands, CXCL9, CXCL10, and CXCL11, as the lack of G alpha(i2) abolished CXCR3-stimulated migration and guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) incorporation. In sharp contrast, T cells isolated from G alpha(i3) knock-out mice displayed a significant increase in both GTPgammaS incorporation and migration as compared with wild type T cells when stimulated with CXCR3 agonists. The increased GTPgammaS incorporation was blocked by G alpha(i3) protein in a dose-dependent manner. G alpha(i3)-mediated blockade of G alpha(i2) activation did not result from G alpha(i3) activation, but instead resulted from competition or steric hindrance of G alpha(i2) interaction with the CXCR3 receptor via the N terminus of the second intracellular loop. A mutation in this domain abrogated not only G alpha(i2) activation induced by a CXCR3 agonist but also the interaction of G alpha(i3) to the CXCR3 receptor. These findings reveal for the first time an interplay of G alpha(i) proteins in transmitting G protein-coupled receptor signals. This interplay has heretofore been masked by the use of pertussis toxin, a broad inhibitor of the G alpha(i/o) protein family.


Assuntos
Subunidade alfa Gi2 de Proteína de Ligação ao GTP/antagonistas & inibidores , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/fisiologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/fisiologia , Receptores de Quimiocinas/fisiologia , Transdução de Sinais/fisiologia , Animais , Células Cultivadas , Quimiocina CXCL10 , Quimiocina CXCL11 , Quimiocina CXCL9 , Quimiocinas CXC/metabolismo , Feminino , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/deficiência , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/deficiência , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores CXCR3 , Receptores de Quimiocinas/metabolismo , Transdução de Sinais/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo
7.
Bioorg Med Chem Lett ; 15(23): 5257-61, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16168640

RESUMO

We report the synthesis and biological activity of a series of 2-cyano-4-fluoro-1-thiovalylpyrrolidine inhibitors of DPP-IV. Within this series, compound 19 provided a potent, selective, and orally active DPP-IV inhibitor which demonstrated a very long duration of action in both rat and dog.


Assuntos
Dipeptidil Peptidase 4/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Pirrolidinas/química , Pirrolidinas/farmacologia , Valina/análogos & derivados , Administração Oral , Animais , Cães , Inibidores de Proteases/síntese química , Pirrolidinas/síntese química , Ratos , Valina/síntese química , Valina/química , Valina/farmacologia
8.
J Neurochem ; 90(3): 646-53, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15255942

RESUMO

Inhibition of astrocyte proliferation has been suggested to be an important event in the developmental neurotoxicity associated with ethanol. We have previously shown that the acetylcholine analog carbachol induces astroglial cell proliferation through activation of muscarinic M3 receptors, and that ethanol strongly inhibits this effect by inhibiting activation of protein kinase C (PKC) zeta and its down-stream effector 70-kDa ribosomal S6 kinase (p70S6K). In this study, we investigated whether inhibition by ethanol of this signal transduction pathway in 1321N1 human astrocytoma cells may be due, at least in part, to inhibition of the formation of the PKC zeta activator phosphatidic acid (PA), which is formed by hydrolysis of phosphatidylcholine by phospholipase D (PLD). 1-Butanol, which is a substrate for PLD and inhibits PA formation, inhibited carbachol-induced cell proliferation and the underlying intracellular signaling, whereas its analog tert-butanol, which is a poor substrate for PLD, was much less effective. In addition, exogenous PAs were able to increase DNA synthesis and to activate PKC zeta and p70S6K. Furthermore, in carbachol-stimulated cells, ethanol increased the formation of phosphatidylethanol and inhibited the formation of PA. Taken together, these results indicate that PLD activation plays an important role in carbachol-induced astroglial cell proliferation by generating the second messenger PA, which activates PKC zeta. Moreover, the effect of ethanol on carbachol-induced proliferation appears to be mediated, at least in part, by its ability to interact with PLD leading to a decreased synthesis of PA.


Assuntos
Astrocitoma/metabolismo , Carbacol/farmacologia , DNA/biossíntese , Etanol/farmacologia , Fosfolipase D/metabolismo , Transdução de Sinais/fisiologia , 1-Butanol/farmacologia , Astrocitoma/tratamento farmacológico , Astrocitoma/enzimologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Agonistas Colinérgicos/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Ácidos Fosfatídicos/metabolismo , Ácidos Fosfatídicos/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , terc-Butil Álcool/farmacologia
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