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1.
Artigo em Inglês | MEDLINE | ID: mdl-38064618

RESUMO

Aims: An imaging study to investigate electroconvulsive modulation of brain markers of emotional processing and activity of various brain regions in patients with schizophrenia. Materials and Methods: One hundred and twenty patients with schizophrenia admitted to The Brain Hospital of Hunan Province from January 2020 to July 2022 were divided into a comparison group and a study group of 60 patients each according to the order of admission. The comparison group received conventional pharmacological interventions and the study group implemented conventional pharmacological and electroconvulsive modulation therapy to compare the neurotransmitter power, neuropsychological assessment, and efficacy evaluation between the two groups. Results: Before treatment, there was no statistically significant difference in neurotransmitter power between the two groups (P > .05); 30 min after treatment, GABA, Glu, 5-HT, Ach, NE, and DA were elevated in both groups and were higher in the study group than in the comparison group, and the difference was statistically significant (P < .05). Before treatment, there was no statistically significant difference in the neuropsychological measurements between the two groups (P > .05). Clinical efficacy evaluation after treatment revealed that the clinical efficacy rate of patients in the study group was 95.00% significantly higher than that of the comparison group, which was 83.33%, and the comparative difference was statistically significant (P < .05). Conclusion: Electroconvulsive therapy was found to significantly improve neuropsychological assessment and clinical outcomes in patients with psychiatric disorders.

2.
Artigo em Inglês | MEDLINE | ID: mdl-30373794

RESUMO

Tedizolid phosphate, the prodrug of the active antibiotic tedizolid, is an oxazolidinone for the treatment of acute bacterial skin and skin structure infections. Studies in a mouse thigh infection model demonstrated that tedizolid has improved potency and pharmacokinetics/pharmacodynamics (PK/PD) compared with those of linezolid. Subsequent studies showed that the efficacy of tedizolid was enhanced in immunocompetent (IC) mice compared with neutropenic (immunosuppressed [IS]) mice, with stasis at clinically relevant doses being achieved only in the presence of granulocytes. The tedizolid label therefore contains a warning about its use in neutropenic patients. This study reevaluated the PK/PD of tedizolid and linezolid in the mouse thigh infection model in IC and IS mice using a methicillin-resistant Staphylococcus aureus (MRSA) strain (ATCC 33591) and a methicillin-susceptible S. aureus (MSSA) strain (ATCC 29213). The antistaphylococcal effect of doses ranging from 1 to 150 mg/kg of body weight tedizolid (once daily) or linezolid (twice daily) was determined at 24, 48, and 72 h after initiating treatment. In IC mice, stasis was achieved in the absence of antibiotics, and both tedizolid and linezolid reduced the burden further beyond a static effect. In IS mice, tedizolid achieved stasis against MRSA ATCC 33591 and MSSA ATCC 29213 at 72 h at a human clinical dose of 200 mg, severalfold lower than that in earlier studies. Linezolid achieved a static effect against MRSA ATCC 33591 in IS mice at a dose lower than that used clinically. This study demonstrates that, with time, both tedizolid and linezolid at clinically relevant exposures achieve stasis in neutropenic mice with an MRSA or MSSA thigh infection.


Assuntos
Antibacterianos/farmacologia , Linezolida/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Neutropenia/metabolismo , Organofosfatos/farmacologia , Oxazóis/farmacologia , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/farmacocinética , Modelos Animais de Doenças , Linezolida/farmacocinética , Camundongos , Testes de Sensibilidade Microbiana , Organofosfatos/farmacocinética , Oxazóis/farmacocinética , Infecções Cutâneas Estafilocócicas/microbiologia
3.
Bioorg Med Chem Lett ; 29(10): 1182-1186, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30926247

RESUMO

Previously disclosed benzimidazole-based DGAT1 inhibitors containing a cyclohexane carboxylic acid moiety suffer from isomerization at the alpha position of the carboxylic acid group, generating active metabolites which exhibit DGAT1 inhibition comparable to the corresponding parent compounds. In this report, we describe the design, synthesis and profiling of benzimidazole-based DGAT1 inhibitors with a [3.1.0] bicyclohexane carboxylic acid moiety. Our results show that single isomer 3A maintains in vitro and in vivo inhibition against DGAT1. In contrast to previous lead compounds, 3A does not undergo isomerization during in vitro hepatocyte incubation study or in vivo mouse study.


Assuntos
Benzimidazóis/química , Ácidos Carboxílicos/química , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Inibidores Enzimáticos/química , Animais , Benzimidazóis/metabolismo , Ácidos Carboxílicos/metabolismo , Cromatografia Líquida de Alta Pressão , Cicloexanonas/química , Diacilglicerol O-Aciltransferase/metabolismo , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/metabolismo , Hepatócitos/química , Hepatócitos/metabolismo , Humanos , Concentração Inibidora 50 , Isomerismo , Espectrometria de Massas , Camundongos , Ratos
4.
Bioorg Med Chem Lett ; 29(11): 1380-1385, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952592

RESUMO

The parallel medicinal chemistry (PMC) was effectively applied to accelerate the optimization of diacylglycerol O-acyltransferase I (DGAT-1) inhibitors. Through a highly collaborative and iterative library design, synthesis and testing, a benzimidazole lead was rapidly and systematically advanced to a highly potent, selective and bioavailable DGAT1 inhibitor with the potential for further development.


Assuntos
Benzimidazóis/farmacologia , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/química , Química Farmacêutica , Diacilglicerol O-Aciltransferase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
5.
Biochem Biophys Res Commun ; 499(2): 299-306, 2018 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-29574155

RESUMO

Apoptosis plays a critical role in normal embryonic development and tissue homeostasis regulation. EndophilinA2 (EndoA2) is widely reported to regulate endocytosis. Additionally, EndoA2 has been demonstrated to be involved in tumor metastasis, neuroregulation and vascular function. In this study, we used siRNA and Ad-EndoA2 transfection strategy to investigate whether EndoA2 provides a protective effect against apoptosis induced by H2O2 in H9C2 cardiomyocytes and the underlying mechanisms. We found that EndoA2 siRNA knockdown promoted H2O2-induced apoptosis in H9C2 cardiomyocytes, evidenced by decreased cell number, increased apoptotic cells, and activation of caspase-3. In contrast, EndoA2 overexpression showed the opposite effects and inhibited H2O2-induced apoptosis in H9C2 cardiomyocytes. Further studies revealed that EndoA2 overexpression strengthened autophagy, evidenced by the increased LC3 II/I ratio and P62 degradation, whereas EndoA2 siRNA knockdown produced the opposite effects. Furthermore, we revealed that there was an interaction between Bif-1 and Beclin-1. Upon H2O2 treatment, the association of Bif-1 and Beclin-1 remarkably increased. EndoA2 overexpression further promoted the binding of Bif-1 with Beclin-1, whereas EndoA2 siRNA knockdown reduced this association. These data strongly suggested that EndoA2 inhibited H2O2-induced apoptosis in H9C2 cardiomyocytes, possibly by promoting Bif-1 to form a complex with Beclin-1 and strengthening autophagy. This study provides a novel target for heart diseases.


Assuntos
Aciltransferases/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Cardiotônicos/metabolismo , Peróxido de Hidrogênio/toxicidade , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteína Beclina-1/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ratos
6.
PLoS Pathog ; 12(5): e1005585, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27144276

RESUMO

Here we describe a chemical biology strategy performed in Staphylococcus aureus and Staphylococcus epidermidis to identify MnaA, a 2-epimerase that we demonstrate interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. Genetic inactivation of mnaA results in complete loss of WTA and dramatic in vitro ß-lactam hypersensitivity in methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE). Likewise, the ß-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSA and MRSE infection. Interestingly, whereas MnaA serves as the sole 2-epimerase required for WTA biosynthesis in S. epidermidis, MnaA and Cap5P provide compensatory WTA functional roles in S. aureus. We also demonstrate that MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSA and MRSE. We further determine the 1.9Å crystal structure of S. aureus MnaA and identify critical residues for enzymatic dimerization, stability, and substrate binding. Finally, the natural product antibiotic tunicamycin is shown to physically bind MnaA and Cap5P and inhibit 2-epimerase activity, demonstrating that it inhibits a previously unanticipated step in WTA biosynthesis. In summary, MnaA serves as a new Staphylococcal antibiotic target with cognate inhibitors predicted to possess dual therapeutic benefit: as combination agents to restore ß-lactam efficacy against MRSA and MRSE and as non-bioactive prophylactic agents to prevent Staphylococcal biofilm formation.


Assuntos
Proteínas de Bactérias/metabolismo , Racemases e Epimerases/metabolismo , Staphylococcus aureus/metabolismo , Staphylococcus epidermidis/metabolismo , Ácidos Teicoicos/biossíntese , Animais , Proteínas de Bactérias/química , Biofilmes/crescimento & desenvolvimento , Parede Celular/metabolismo , Cristalografia por Raios X , Modelos Animais de Doenças , Staphylococcus aureus Resistente à Meticilina , Camundongos , Testes de Sensibilidade Microbiana , Microscopia de Fluorescência , Ressonância Magnética Nuclear Biomolecular , Racemases e Epimerases/química , Infecções Estafilocócicas/metabolismo
7.
Anal Biochem ; 518: 9-15, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27815077

RESUMO

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has created an urgent need for new therapeutic agents capable of combating this threat. We have previously reported on the discovery of novel inhibitors targeting enzymes involved in the biosynthesis of wall teichoic acid (WTA) and demonstrated that these agents can restore ß-lactam efficacy against MRSA. In those previous reports pathway engagement of inhibitors was demonstrated by reduction in WTA levels measured by polyacrylamide gel electrophoresis. To enable a more rigorous analysis of these inhibitors we sought to develop a quantitative method for measuring whole-cell reductions in WTA. Herein we describe a robust methodology for hydrolyzing polymeric WTA to the monomeric component ribitol-N-acetylglucosamine coupled with measurement by LC-MS/MS. Critical elements of the protocol were found to include the time and temperature of hydrofluoric acid-mediated hydrolysis of polymeric WTA and optimization of these parameters is fully described. Most significantly, the assay enabled accurate and reproducible measurement of depletion EC50s for tunicamycin and representatives from the novel class of TarO inhibitors, the tarocins. The method described can readily be adapted to quantifying levels of WTA in tissue homogenates from a murine model of infection, highlighting the applicability for both in vitro and in vivo characterizations.


Assuntos
Espectrometria de Massas/métodos , Staphylococcus aureus Resistente à Meticilina/metabolismo , Ácidos Teicoicos/metabolismo , Cromatografia Líquida/métodos , Staphylococcus aureus Resistente à Meticilina/química , Ácidos Teicoicos/química , Tunicamicina/farmacologia
8.
J Pharmacol Exp Ther ; 359(1): 194-206, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27432892

RESUMO

The renal outer medullary potassium (ROMK) channel, located at the apical surface of epithelial cells in the thick ascending loop of Henle and cortical collecting duct, contributes to salt reabsorption and potassium secretion, and represents a target for the development of new mechanism of action diuretics. This idea is supported by the phenotype of antenatal Bartter's syndrome type II associated with loss-of-function mutations in the human ROMK channel, as well as, by cardiovascular studies of heterozygous carriers of channel mutations associated with type II Bartter's syndrome. Although the pharmacology of ROMK channels is still being developed, channel inhibitors have been identified and shown to cause natriuresis and diuresis, in the absence of any significant kaliuresis, on acute oral dosing to rats or dogs. Improvements in potency and selectivity have led to the discovery of MK-7145 [5,5'-((1R,1'R)-piperazine-1,4-diylbis(1-hydroxyethane-2,1-diyl))bis(4-methylisobenzofuran-1(3H)-one)], a potential clinical development candidate. In spontaneously hypertensive rats, oral dosing of MK-7145 causes dose-dependent lowering of blood pressure that is maintained during the entire treatment period, and that displays additive/synergistic effects when administered in combination with hydrochlorothiazide or candesartan, respectively. Acute or chronic oral administration of MK-7145 to normotensive dogs led to dose-dependent diuresis and natriuresis, without any significant urinary potassium losses or changes in plasma electrolyte levels. Elevations in bicarbonate and aldosterone were found after 6 days of dosing. These data indicate that pharmacological inhibition of ROMK has potential as a new mechanism for the treatment of hypertension and/or congestive heart failure. In addition, Bartter's syndrome type II features are manifested on exposure to ROMK inhibitors.


Assuntos
Síndrome de Bartter/fisiopatologia , Benzofuranos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Fenótipo , Piperazinas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Animais , Síndrome de Bartter/tratamento farmacológico , Benzimidazóis/farmacologia , Benzofuranos/uso terapêutico , Compostos de Bifenilo , Cães , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Células HEK293 , Humanos , Hidroclorotiazida/farmacologia , Masculino , Piperazinas/uso terapêutico , Bloqueadores dos Canais de Potássio/uso terapêutico , Ratos , Tetrazóis/farmacologia
9.
J Pharmacol Exp Ther ; 348(1): 153-64, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24142912

RESUMO

The renal outer medullary potassium (ROMK) channel, which is located at the apical membrane of epithelial cells lining the thick ascending loop of Henle and cortical collecting duct, plays an important role in kidney physiology by regulating salt reabsorption. Loss-of-function mutations in the human ROMK channel are associated with antenatal type II Bartter's syndrome, an autosomal recessive life-threatening salt-wasting disorder with mild hypokalemia. Similar observations have been reported from studies with ROMK knockout mice and rats. It is noteworthy that heterozygous carriers of Kir1.1 mutations associated with antenatal Bartter's syndrome have reduced blood pressure and a decreased risk of developing hypertension by age 60. Although selective ROMK inhibitors would be expected to represent a new class of diuretics, this hypothesis has not been pharmacologically tested. Compound A [5-(2-(4-(2-(4-(1H-tetrazol-1-yl)phenyl)acetyl)piperazin-1-yl)ethyl)isobenzofuran-1(3H)-one)], a potent ROMK inhibitor with appropriate selectivity and characteristics for in vivo testing, has been identified. Compound A accesses the channel through the cytoplasmic side and binds to residues lining the pore within the transmembrane region below the selectivity filter. In normotensive rats and dogs, short-term oral administration of compound A caused concentration-dependent diuresis and natriuresis that were comparable to hydrochlorothiazide. Unlike hydrochlorothiazide, however, compound A did not cause any significant urinary potassium losses or changes in plasma electrolyte levels. These data indicate that pharmacologic inhibition of ROMK has the potential for affording diuretic/natriuretic efficacy similar to that of clinically used diuretics but without the dose-limiting hypokalemia associated with the use of loop and thiazide-like diuretics.


Assuntos
Diurese/efeitos dos fármacos , Diurese/fisiologia , Natriurese/efeitos dos fármacos , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/fisiologia , Animais , Células CHO , Cricetinae , Cricetulus , Cães , Relação Dose-Resposta a Droga , Feminino , Células HEK293 , Humanos , Células Madin Darby de Rim Canino , Masculino , Natriurese/fisiologia , Ratos , Ratos Sprague-Dawley
10.
ISA Trans ; 142: 325-334, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37586934

RESUMO

This paper investigates the stabilization problem of switched systems with mismatched modes by an event-triggered control approach. A hybrid event-triggered scheme (HETS) with a dynamically adjustable threshold is newly proposed, which combines periodic sampling, continuous event-trigger and slow switching. It is assumed that the modes and states of the controller are updated only at each triggering instant, so the situation of asynchronous switching could arise. Compared with the control strategy under static HETS, the proposed hybrid event-triggered control strategy has the advantage of potentially speeding up the stabilization while reducing the communication burden. To ease the analysis, the closed-loop system is accordingly represented as a combination of the switched system with a periodically sampled control input and the one with a continuously event-triggered control input. By considering input delay information in the construction of multiple Lyapunov-Krasovskii functional (LKF), a discontinuous and non-positive definite LKF is developed to establish sufficient conditions on the exponential stability for the closed-loop switched system. The design method of the desired controller and HETS is then provided. Finally, the result obtained in this paper is applied to a networked continuous stirred tank reactors system.

11.
Neural Netw ; 163: 28-39, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37023543

RESUMO

This paper addresses fixed-time output synchronization problems for two types of complex dynamical networks with multi-weights (CDNMWs) by using two types of adaptive control methods. Firstly, complex dynamical networks with multiple state and output couplings are respectively presented. Secondly, several fixed-time output synchronization criteria for these two networks are formulated based on Lyapunov functional and inequality techniques. Thirdly, by employing two types of adaptive control methods, fixed-time output synchronization issues of these two networks are dealt with. At last, the analytical results are verified by two numerical simulations.


Assuntos
Algoritmos , Redes Neurais de Computação , Fatores de Tempo
12.
J Biol Chem ; 286(12): 10356-66, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21212267

RESUMO

It is well documented that protein kinase A (PKA) acts as a negative regulator of M phase promoting factor (MPF) by phosphorylating cell division cycle 25 homolog B (Cdc25B) in mammals. However, the molecular mechanism remains unclear. In this study, we identified PKA phosphorylation sites in vitro by LC-MS/MS analysis, including Ser(149), Ser(229), and Ser(321) of Cdc25B, and explored the role of Ser(149) in G(2)/M transition of fertilized mouse eggs. The results showed that the overexpressed Cdc25B-S149A mutant initiated efficient MPF activation by direct dephosphorylation of Cdc2-Tyr(15), resulting in triggering mitosis prior to Cdc25B-WT. Conversely, overexpression of the phosphomimic Cdc25B-S149D mutant showed no significant difference in comparison with the control groups. Furthermore, we found that Cdc25B-Ser(149) was phosphorylated at G(1) and S phases, whereas dephosphorylated at G(2) and M phases, and the phosphorylation of Cdc25B-Ser(149) was modulated by PKA in vivo. In addition, we examined endogenous and exogenous Cdc25B, which were expressed mostly in the cytoplasm at the G(1) and S phases and translocated to the nucleus at the G(2) phase. Collectively, our findings provide evidence that Ser(149) may be another potential PKA phosphorylation target of Cdc25B in G(2)/M transition of fertilized mouse eggs and Cdc25B as a direct downstream substrate of PKA in mammals, which plays important roles in the regulation of early development of mouse embryos.


Assuntos
Divisão Celular/fisiologia , Núcleo Celular/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fase G2/fisiologia , Zigoto/enzimologia , Fosfatases cdc25/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Substituição de Aminoácidos , Animais , Núcleo Celular/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/enzimologia , Feminino , Masculino , Fator Promotor de Maturação/genética , Fator Promotor de Maturação/metabolismo , Mesotelina , Camundongos , Mutação de Sentido Incorreto , Fosforilação/genética , Serina/genética , Serina/metabolismo , Zigoto/citologia , Fosfatases cdc25/genética
13.
Bioorg Med Chem Lett ; 22(8): 2811-7, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22444683

RESUMO

A new structural class of potent prolylcarboxypeptidase (PrCP) inhibitors was discovered by high-throughput screening. The series possesses a tractable SAR profile with sub-nanomolar in vitro IC(50) values. Compared to prior inhibitors, the new series demonstrated minimal activity shifts in pure plasma and complete ex vivo plasma target engagement in mouse plasma at the 20 h post-dose time point (po). In addition, the in vivo level of CNS and non-CNS drug exposure was measured.


Assuntos
Carboxipeptidases/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos , Animais , Butanóis/síntese química , Butanóis/química , Butanóis/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Obesidade/tratamento farmacológico , Pirrolidinas/síntese química , Pirrolidinas/química , Pirrolidinas/farmacologia
14.
Bioorg Med Chem Lett ; 22(8): 2818-22, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22444685

RESUMO

A series of potent inhibitors of prolylcarboxypeptidase (PrCP) was developed by modifying a lead structure that was discovered by high-throughput screening. The tert-butyl pyrrolidine was replaced by an aminocyclopentane to reduce the metabolic liabilities of the original lead. The compounds demonstrated sub-nanomolar in vitro IC(50) values, minimal activity shifts in pure plasma and improved pharmacokinetics. Complete ex vivo plasma target engagement was achieved with low brain exposure at the 20 h time point following p.o. dosing in a mouse. The results indicate that the aminocyclopentanes are useful tools for studying the therapeutic potential of peripheral (non-CNS) PrCP inhibition.


Assuntos
Aminas/farmacologia , Carboxipeptidases/antagonistas & inibidores , Ciclopentanos/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos , Aminas/síntese química , Aminas/química , Animais , Ciclização , Ciclopentanos/síntese química , Ciclopentanos/química , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Obesidade/tratamento farmacológico
15.
Sheng Li Xue Bao ; 64(1): 33-40, 2012 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-22348958

RESUMO

To further test whether protein kinase A (PKA) can affect the mitotic cell cycle, one-cell stage mouse embryos at S phase (22 h after hCG injection) were incubated in M16 medium containing various concentrations of H-89, a PKA inhibitor. With increasing concentrations of H-89 (0-50 µmol/L), the G(2) phase of eggs was decreased and the cleavage rate was accelerated. A concentration of 40 µmol/L H-89 led to all of the mouse eggs entering the M phase of mitosis. Furthermore, to study the role of PKA in regulating the phosphorylation status of S149 and S321 sites of cell division cycle 25B (CDC25B) on one-cell stage fertilized mouse eggs, pBSK-CDC25B-WT, pBSK-CDC25B-S149A, pBSK-CDC25B-S321A and pBSK-CDC25B-S149A/S321A were transcribed into mRNAs in vitro, then mRNAs were microinjected into S phase of mouse fertilized eggs and cultured in M16 medium pretreated with H-89. Then, the cleavage of fertilized eggs, maturation promoting factor (MPF) activity and phosphorylation status of CDC2-Tyr15 were observed. In the presence of 40 µmol/L H-89, the cleavage rate of fertilized eggs in CDC25B-S/A-mRNAs and CDC25B-WT-mRNA injected groups was significantly higher than that in the control groups, and the peak of MPF activity appeared in the CDC25B-S/A-mRNAs and CDC25B-WT-mRNA injected groups earlier than that in the control groups. CDC2-Tyr15 phosphorylation state was consistent with MPF activity. In conclusion, the present study suggests that PKA regulates the early development of mouse embryos by phosphorylation of S149 and S321 of CDC25B, which plays an important role in the regulation of G(2)/M transition in the mitotic cell cycle of fertilized mouse eggs.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Mitose/efeitos dos fármacos , Zigoto/crescimento & desenvolvimento , Fosfatases cdc25/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/genética , Desenvolvimento Embrionário/fisiologia , Feminino , Masculino , Mesotelina , Camundongos , Microinjeções , Fosforilação , Serina/genética , Serina/metabolismo , Zigoto/citologia , Fosfatases cdc25/genética
16.
IEEE Trans Neural Netw Learn Syst ; 33(10): 5656-5665, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33950847

RESUMO

The unified criteria are analyzed on the global dissipativity and stability for the delayed fractional-order systems of multidimension-valued memristive neural networks (FSMVMNNs) in this article. First, based on the comprehensive knowledge about multidimensional algebra, fractional derivatives, and nonsmooth analysis, we establish the unified model for the studied FSMVMNNs in order to propose a more uniform method to analyze the dynamic behaviors of multidimensional neural networks. Then, by mainly applying the Lyapunov method, employing several new lemmas, and solving some mathematical difficulties, without any separation, we acquire the unified and concise criteria. The derived criteria have many advantages in a smaller calculation, lower conservatism, more diversity, and higher flexibility. Finally, we provide two numerical examples to express the availability and improvements of the theoretical results.


Assuntos
Algoritmos , Redes Neurais de Computação , Conhecimento
17.
Neural Netw ; 154: 491-507, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35970027

RESUMO

In this paper, a new case of neural networks called fractional-order octonion-valued bidirectional associative memory neural networks (FOOVBAMNNs) is established. First, the higher dimensional models are formulated for FOOVBAMNNs with general activation functions and the special linear threshold ones, respectively. On one hand, employing Cayley-Dichson construction in octonion multiplication which is essentially neither commutative nor associative, the system of FOOVBAMNNs is divided into four fractional-order complex-valued ones. On the other hand, Caputo fractional derivative's character and BAM's interactive feature are also properly dealt with. Second, the general criteria are obtained by the new design of LKFs, the application of the related inequalities and the construction of the linear feedback controllers for the global Mittag-Leffler synchronization problem of FOOVBAMNNs. Finally, we present two numerical examples to show the realizability and progress of the derived results.


Assuntos
Redes Neurais de Computação , Retroalimentação
18.
J Exp Med ; 202(4): 517-27, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16103409

RESUMO

The enzyme 11beta-hydroxysteroid dehydrogenase (HSD) type 1 converts inactive cortisone into active cortisol in cells, thereby raising the effective glucocorticoid (GC) tone above serum levels. We report that pharmacologic inhibition of 11beta-HSD1 has a therapeutic effect in mouse models of metabolic syndrome. Administration of a selective, potent 11beta-HSD1 inhibitor lowered body weight, insulin, fasting glucose, triglycerides, and cholesterol in diet-induced obese mice and lowered fasting glucose, insulin, glucagon, triglycerides, and free fatty acids, as well as improved glucose tolerance, in a mouse model of type 2 diabetes. Most importantly, inhibition of 11beta-HSD1 slowed plaque progression in a murine model of atherosclerosis, the key clinical sequela of metabolic syndrome. Mice with a targeted deletion of apolipoprotein E exhibited 84% less accumulation of aortic total cholesterol, as well as lower serum cholesterol and triglycerides, when treated with an 11beta-HSD1 inhibitor. These data provide the first evidence that pharmacologic inhibition of intracellular GC activation can effectively treat atherosclerosis, the key clinical consequence of metabolic syndrome, in addition to its salutary effect on multiple aspects of the metabolic syndrome itself.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Adamantano/análogos & derivados , Arteriosclerose/tratamento farmacológico , Azepinas/administração & dosagem , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Resistência à Insulina , Triazóis/administração & dosagem , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adamantano/administração & dosagem , Animais , Aorta/metabolismo , Arteriosclerose/complicações , Arteriosclerose/enzimologia , Glicemia/efeitos dos fármacos , Cortisona/metabolismo , Dieta Aterogênica , Modelos Animais de Doenças , Ácidos Graxos/sangue , Hidrocortisona , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Síndrome , Triglicerídeos/sangue
19.
Cell Biochem Funct ; 29(4): 265-71, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21671244

RESUMO

Protein kinase B (PKB, also called Akt) is known as a serine/threonine protein kinase. Some studies indicate that the Akt signalling pathway strongly promotes G2/M transition in mammalian cell cycle progression, but the mechanism remains to be clarified, especially in the fertilized mouse egg. Here, we report that the expression of Akt at both the protein and mRNA level was highest in G2 phase, accompanied by a peak of Akt activity. In addition, the subcellular localization of p21(Cip1/WAF1) has been proposed to be critical in the cell cycle. Hence, we detected the expression and localization of p21(Cip1/WAF1) after injecting fertilized mouse eggs with Akt mRNA. In one-cell stage fertilized embryos microinjected with mRNA coding for a constitutively active myristoylated Akt (myr-Akt), p21(Cip1/WAF1) was retained in the cytoplasm. Microinjection of mRNA of kinase-deficient Akt(Akt-KD) resulted in nuclear localization of p21(Cip1/WAF1) . Meanwhile, microinjection of different types of Akt mRNA affected the phosphorylation status of p21(Cip1/WAF1) . However, there was no obvious difference in the protein expression of p21(Cip1/WAF1) . Therefore, Akt controls the cell cycle by changing the subcellular localization of p21(Cip1/WAF1) , most likely by affecting the phosphorylation status of p21(Cip1/WAF1) .


Assuntos
Divisão Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Desenvolvimento Embrionário , Fase G2 , Zigoto/citologia , Animais , Núcleo Celular/metabolismo , Proliferação de Células , Citoplasma/metabolismo , Feminino , Imunofluorescência , Masculino , Camundongos , Microinjeções , Oócitos/citologia , Oócitos/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Zigoto/metabolismo
20.
Neural Netw ; 133: 87-100, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33152567

RESUMO

This paper studies the problem of the global Mittag-Leffler synchronization for fractional-order multidimension-valued BAM neural networks (FOMVBAMNNs) with general activation functions (AFs). First, the unified model is established for the researched systems of FOMVBAMNNs which can be turned into the corresponding multidimension-valued systems as long as the state variables, the connection weights and the AFs of the neural networks are valued to be real, complex, or quaternion. Then, without any decomposition, the criteria in unified form are derived by constructing the new Lyapunov-Krasovskii functionals (LKFs) in vector form, combining two new inequalities and considering the easy controllers. It is worth mentioning that the obtained criteria have many advantages in higher flexibility, more diversity, smaller computation, and lower conservatism. Finally, a simulation example is provided to illustrate the availability and improvements of the acquired results.


Assuntos
Simulação por Computador , Redes Neurais de Computação
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