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1.
J Phys Chem A ; 127(8): 2034-2040, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36791330

RESUMO

We apply the Self-Consistent Effective Hamiltonian Theory (SCEHT), which uses a general variational Fermionic many-body wave function to generate an effective Hamiltonian in a quadratic form, to the Anderson impurity model. The chiral symmetry-breaking quadratic effective Hamiltonian is solved exactly for the single Fermion excitation spectrum. We validate the theory by numerically solving a model problem. The solution shows the correct Kondo resonance in the quasi-particle density of states.

2.
Int Immunopharmacol ; 135: 112223, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38772295

RESUMO

Although smoking is a significant risk factor for osteomyelitis, there is limited experimental evidence that nicotine, a key tobacco constituent, is associated with this condition, leaving its mechanistic implications uncharacterized. This study revealed that nicotine promotes Staphylococcus aureus-induced osteomyelitis by increasing Nrf2 and Slc7a11 expression in vivo and in vitro. Inhibition of Slc7a11 using Erastin augmented bacterial phagocytosis/killing capabilities and fortified antimicrobial responses in an osteomyelitis model. Moreover, untargeted metabolomic analysis demonstrated that Erastin mitigated the effects of nicotine on S. aureus-induced osteomyelitis by altering glutamate/glutathione metabolism. These findings suggest that nicotine aggravates S. aureus-induced osteomyelitis by activating the Nrf2/Slc7a11 signaling pathway and that Slc7a11 inhibition can counteract the detrimental health effects of nicotine.


Assuntos
Sistema y+ de Transporte de Aminoácidos , Fator 2 Relacionado a NF-E2 , Nicotina , Osteomielite , Transdução de Sinais , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Nicotina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Osteomielite/microbiologia , Osteomielite/tratamento farmacológico , Osteomielite/metabolismo , Camundongos , Sistema y+ de Transporte de Aminoácidos/metabolismo , Camundongos Endogâmicos C57BL , Humanos , Masculino , Fagocitose/efeitos dos fármacos , Modelos Animais de Doenças
3.
Materials (Basel) ; 16(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36770287

RESUMO

FeSiBCuNb powders prepared by the gas atomization method generally exhibit a wide particle size distribution and a high degree of sphericity. In addition, the correspondingly prepared nanocrystalline soft magnetic composites (NSMCs) perform good service stability. In this paper, effects of the gas-atomization pressure and annealing temperature on the microstructure and soft magnetic properties of FeSiBCuNb powders and NSMCs are investigated. The results show that the powders obtained by a higher gas-atomization pressure possess a larger amorphous ratio and a smaller average crystallite size, which contribute to the better soft magnetic performance of the NSMCs. After being annealed at 550 °C for 60 min, the NSMCs show a much better performance than those treated by the stress-relief annealing process under 300 °C, which indicates that the optimization of the soft magnetic properties resulting from the precipitation of the α-Fe(Si) nanocrystalline largely overwhelms the deterioration caused by the grain growth of the pre-existing crystals. In addition, the annealed NSMCs prepared by the powders with the gas-atomization pressure of 4 MPa show the best performance in this work, µe = 33.32 (f = 100 kHz), Hc = 73.08 A/m and Pcv = 33.242 mW/cm3 (f = 100 kHz, Bm = 20 mT, sine wave).

4.
Antioxidants (Basel) ; 11(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36421451

RESUMO

Heterotopic ossification (HO) is defined as the generation of pathological ectopic bony structures in soft tissues, but the molecular mechanisms of tendon HO are not fully revealed. Hedgehog (Hh) signalling is reportedly critical in hereditary HO. Our study focuses on the role of Hh signalling in the formation of trauma-induced tendon ossification. In this study, samples of healthy tendons and injured tendons from C57BL/6J female mice at 1, 4, 7, and 10 weeks after Achilles tenotomy were collected for quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical analysis (IHC). At 1, 4, 7, and 10 weeks postinjury, tendon samples from the mice administered with vehicle, GANT58 (a GLI antagonist), or SAG (a smoothened agonist) were harvested for micro-CT, histological staining, qRT-PCR, and IHC. Rat tendon-derived stem cells (TDSCs) treated with vehicle, GANT58, or SAG were used to induce osteogenic and chondrogenic differentiation in vitro for qRT-PCR, alkaline phosphatase staining, Alcian blue staining, and reactive oxygen species (ROS) levels measurement. We found that Hh signalling is remarkably activated during the formation of trauma-induced tendon ossification in the model of Achilles tenotomy. The in vitro and in vivo assays both confirm that downregulation of Hh signalling significantly suppresses osteogenesis and chondrogenesis to inhibit tendon ossification, while upregulation of Hh signalling promotes this process. Under osteogenic induction, Hh signalling regulates antioxidant pathway and affects ROS generation of TDSCs. Collectively, Hh signalling contributes to trauma-induced tendon ossification and affects ROS generation through antioxidant pathway in osteogenic differentiation of TDSCs, indicating that targeting Hh signalling by GANT58 may be a potential treatment for trauma-induced tendon ossification.

5.
Biomed Environ Sci ; 23(2): 113-20, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20514986

RESUMO

OBJECTIVE: To explore Effects of marine collagen peptides (MCPs) on markers of metablic nuclear receptors, i.e peroxisome proliferator-activated receptor (PPARs), liver X receptor (LXRs) and farnesoid X receptor (FXRs) in type 2 diabetic patients with/without hypertension. METHOD Study population consisted of 200 type 2 diabetic patients with/without hypertension and 50 healthy subjects, all of whom were randomly assigned to MCPs-treated diabetics (n = 50), placebo-treated diabetics (n = 50), MCPs-treated diabetics with hypertension (n=50), placebo-treated diabetics with hypertension (n = 50), and healthy controls (n = 50). MCPs or placebo (water-soluble starch) were given daily before breakfast and bedtime over three months. Levels of free fatty acid, cytochrome P450, leptin, resistin, adiponectin, bradykinin, NO, and Prostacyclin were determined before intervention, and 1.5 months, and 3 months after intervention. Hypoglycemia and the endpoint events during the study were recorded and compared among the study groups. RESULT: At the end of the study period, MCPs-treated patients showed marked improvement compared with patients receiving placebo. The protection exerted by MCPs seemed more profound in diabetics than in diabetics with hypertension. In particular, after MCPs intervention, levels of free fatty acid, hs-CRP, resistin, Prostacyclin decreased significantly in diabetics and tended to decrease in diabetic and hypertensive patients whereas levels of cytochrome P450, leptin, NO tended to decrease in diabetics with/without hypertension. Meanwhile, levels of adiponectin and bradykinin rose markedly in diabetics following MCPs administration. CONCLUSION: MCPs could offer protection against diabetes and hypertension by affecting levels of molecules involved in diabetic and hypertensive pathogenesis. Regulation on metabolic nuclear receptors by MCPs may be the possible underlying mechanism for its observed effects in the study. Further study into its action may shed light on development of new drugs based on bioactive peptides from marine sources.


Assuntos
Colágeno/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipertensão/tratamento farmacológico , Peptídeos/uso terapêutico , Receptores Citoplasmáticos e Nucleares/metabolismo , Adipocinas/sangue , Idoso , Biomarcadores/sangue , Bradicinina/sangue , Proteína C-Reativa/metabolismo , Sistema Enzimático do Citocromo P-450/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Epoprostenol/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Hipertensão/sangue , Hipertensão/complicações , Masculino , Biologia Marinha , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Estudos Prospectivos
6.
Appl Physiol Nutr Metab ; 35(6): 797-804, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21164551

RESUMO

This study was aimed at examining the therapeutic effects of marine collagen peptides (MCPs) from fish hydrolysate in Chinese patients with type 2 diabetes mellitus (T2DM). A total of 100 diabetic patients and 50 healthy controls were recruited. Diabetic patients were randomized into treatment and control groups. The patients in the treatment group received an additional 13 g of MCPs daily for 3 months. Their blood samples were collected before, and 1.5 and 3 months after, treatment to evaluate glucose and lipid metabolism. The levels of serum high-sensitivity C-reactive protein (hs-CRP), nitric oxide (NO), bradykinin, prostacyclin (PGI2), and adipokines were determined. Significantly reduced levels of fasting blood glucose, human glycated hemoglobin A1c (GHbA1c), fasting blood insulin, total triglycerides, total cholesterol, low-density lipoprotein, and free-fatty acids, but increased levels of insulin sensitivity index and HDL were observed in T2DM patients following treatment with MCPs for 1.5 and 3 months. The values of these measures were significantly lower or higher than those of patient controls (p < 0.01), respectively. Interestingly, significantly decreased levels of hs-CRP and NO, but increased levels of bradykinin, PGI2, and adiponectin were detected in MCP-treated T2DM patients (p < 0.01), as compared with their basal values or the levels in patient controls. MCP treatment improved glucose and lipid metabolism in diabetic patients.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/dietoterapia , Suplementos Nutricionais , Peixes , Lipídeos/sangue , Hidrolisados de Proteína/uso terapêutico , Adipocinas/sangue , Idoso , Animais , Proteína C-Reativa/análise , China , Colágeno/metabolismo , Colágeno/uso terapêutico , Feminino , Hemoglobinas Glicadas/análise , Humanos , Mediadores da Inflamação/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Hidrolisados de Proteína/química , Fatores de Tempo
7.
Am J Med Sci ; 340(5): 360-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20739874

RESUMO

INTRODUCTION: Marine collagen peptides (MCPs) from deep sea fish are shown to ameliorate hyperlipidemia in animal models. The study aimed at examining the effects of MCPs on glucose and lipid metabolism in Chinese patients with type 2 diabetes mellitus (T2DM) and primary hypertension. METHODS: One hundred patients with T2DM and primary hypertension and 50 healthy subjects (normal controls) were recruited for a randomized double blind study. The patients were randomized into MCPs treatment or patient control groups (n = 50 per group). Both patient controls and normal controls were given carboxymethylcellulose twice daily whereas the MCPs treatment group was given MCPs twice daily for 3 months. Blood pressure, glucose and lipid metabolism, serum high-sensitivity C-reactive protein, cytochrome P450, nitric oxide, bradykinin, prostacyclin, creatinine, uric acid and adipokines were measured at baseline, 1.5 and 3 months after treatment. All patients received regular medicines for control of hyperglycemia and hypertension. RESULTS: Compared with patient controls, significantly reduced levels of fasting blood glucose, HbA1c, diastolic blood pressure, mean arterial pressure and creatinine but increased levels of Insulin Sensitivity Index and Insulin Secretion Index were observed in patients receiving MCPs treatment. Furthermore, significantly reduced levels of serum triglycerides, total cholesterol, low-density lipoprotein, free fatty acids, cytochrome P450, nitric oxide and prostacyclin but increased levels of high-density lipoprotein, bradykinin and adiponectin were detected in patients taking MCPs. CONCLUSIONS: MCPs supplement may benefit glucose and lipid metabolism, insulin sensitivity, renal function and hypertension management in Chinese patients with T2DM and hypertension.


Assuntos
Colágeno/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipertensão/tratamento farmacológico , Peptídeos/uso terapêutico , Idoso , Animais , Povo Asiático , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Colágeno/farmacologia , Método Duplo-Cego , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Peptídeos/farmacologia
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