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1.
Nat Biotechnol ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744947

RESUMO

Cancer immunotherapy with autologous chimeric antigen receptor (CAR) T cells faces challenges in manufacturing and patient selection that could be avoided by using 'off-the-shelf' products, such as allogeneic CAR natural killer T (AlloCAR-NKT) cells. Previously, we reported a system for differentiating human hematopoietic stem and progenitor cells into AlloCAR-NKT cells, but the use of three-dimensional culture and xenogeneic feeders precluded its clinical application. Here we describe a clinically guided method to differentiate and expand IL-15-enhanced AlloCAR-NKT cells with high yield and purity. We generated AlloCAR-NKT cells targeting seven cancers and, in a multiple myeloma model, demonstrated their antitumor efficacy, expansion and persistence. The cells also selectively depleted immunosuppressive cells in the tumor microenviroment and antagonized tumor immune evasion via triple targeting of CAR, TCR and NK receptors. They exhibited a stable hypoimmunogenic phenotype associated with epigenetic and signaling regulation and did not induce detectable graft versus host disease or cytokine release syndrome. These properties of AlloCAR-NKT cells support their potential for clinical translation.

2.
Mol Ther ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38584391

RESUMO

The clinical potential of current FDA-approved chimeric antigen receptor (CAR)-engineered T (CAR-T) cell therapy is encumbered by its autologous nature, which presents notable challenges related to manufacturing complexities, heightened costs, and limitations in patient selection. Therefore, there is a growing demand for off-the-shelf universal cell therapies. In this study, we have generated universal CAR-engineered NKT (UCAR-NKT) cells by integrating iNKT TCR engineering and HLA gene editing on hematopoietic stem cells (HSCs), along with an ex vivo, feeder-free HSC differentiation culture. The UCAR-NKT cells are produced with high yield, purity, and robustness, and they display a stable HLA-ablated phenotype that enables resistance to host cell-mediated allorejection. These UCAR-NKT cells exhibit potent antitumor efficacy to blood cancers and solid tumors, both in vitro and in vivo, employing a multifaceted array of tumor-targeting mechanisms. These cells are further capable of altering the tumor microenvironment by selectively depleting immunosuppressive tumor-associated macrophages and myeloid-derived suppressor cells. In addition, UCAR-NKT cells demonstrate a favorable safety profile with low risks of graft-versus-host disease and cytokine release syndrome. Collectively, these preclinical studies underscore the feasibility and significant therapeutic potential of UCAR-NKT cell products and lay a foundation for their translational and clinical development.

3.
Sci Adv ; 9(42): eadj0540, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37851816

RESUMO

The current cardiac pacemakers are battery dependent, and the pacing leads are prone to introduce valve damage and infection, plus a complete pacemaker retrieval is needed for battery replacement. Despite the reported wireless bioelectronics to pace the epicardium, open-chest surgery (thoracotomy) is required to implant the device, and the procedure is invasive, requiring prolonged wound healing and health care burden. We hereby demonstrate a fully biocompatible wireless microelectronics with a self-assembled design that can be rolled into a lightweight microtubular pacemaker for intravascular implantation and pacing. The radio frequency was used to transfer energy to the microtubular pacemaker for electrical stimulation. We show that this pacemaker provides effective pacing to restore cardiac contraction from a nonbeating heart and have the capacity to perform overdrive pacing to augment blood circulation in an anesthetized pig model. Thus, this microtubular pacemaker paves the way for the minimally invasive implantation of leadless and battery-free microelectronics.


Assuntos
Estimulação Cardíaca Artificial , Marca-Passo Artificial , Animais , Suínos , Estimulação Cardíaca Artificial/métodos , Próteses e Implantes , Coração , Estimulação Elétrica , Desenho de Equipamento , Resultado do Tratamento
4.
iScience ; 26(10): 107952, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37810241

RESUMO

Ovarian cancer (OC) is highly lethal due to late detection and frequent recurrence. Initial treatments, comprising surgery and chemotherapy, lead to disease remission but are invariably associated with subsequent relapse. The identification of novel therapies and an improved understanding of the molecular and cellular characteristics of OC are urgently needed. Here, we conducted a comprehensive analysis of primary tumor cells and their microenvironment from 16 chemonaive and 10 recurrent OC patient samples. Profiling OC tumor biomarkers allowed for the identification of potential molecular targets for developing immunotherapies, while profiling the microenvironment yielded insights into its cellular composition and property changes between chemonaive and recurrent samples. Notably, we identified CD1d as a biomarker of the OC microenvironment and demonstrated its targeting by invariant natural killer T (iNKT) cells. Overall, our study presents a comprehensive immuno-profiling of OC tumor and microenvironment during disease progression, guiding the development of immunotherapies for OC treatment, especially for recurrent disease.

5.
World J Clin Cases ; 11(25): 6005-6011, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37727479

RESUMO

BACKGROUND: A carotid-cavernous fistula (CCF) is an abnormal connection between the internal carotid artery (ICA) and the cavernous sinus. Although direct CCFs typically result from trauma or as an iatrogenic complication of neuroendovascular procedures, they can occur as surgery-related complications after mechanical thrombectomy (MT). With the widespread use of MT in patients with acute ischemic stroke complicated with large vessel occlusion, it is important to document CCF following MT and how to avoid them. In this study, we present a case of a patient who developed a CCF following MT and describe in detail the characteristics of ICA tortuosity in this case. CASE SUMMARY: A 60-year-old woman experienced weakness in the left upper and lower limbs as well as difficulty speaking for 4 h. The neurological examination revealed left central facial paralysis and left hemiplegia, with a National Institutes of Health Stroke Scale score of 9. Head magnetic resonance imaging revealed an acute cerebral infarction in the right basal ganglia and radial crown. Magnetic resonance angiography demonstrated an occlusion of the right ICA and middle cerebral artery. Digital subtraction angiography demonstrated distal occlusion of the cervical segment of the right ICA. We performed suction combined with stent thrombectomy. Then, postoperative angiography was performed, which showed a right CCF. One month later, CCF embolization was performed, and the patient's clinical symptoms have significantly improved 5 mo after the operation. CONCLUSION: Although a CCF is a rare complication after MT, it should be considered. Understanding the tortuosity of the internal carotid-cavernous sinus may help predict the complexity of MT and avoid this complication.

6.
ACS Nano ; 17(14): 14152-14160, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37410702

RESUMO

Extensive macroscale two-dimensional (2-D) platinum (Pt) nanowire network (NWN) sheets are created through a hierarchical self-assembly process with the aid of biomolecular ligands. The Pt NWN sheet is assembled from the attachment growth of 1.9 nm-sized 0-D nanocrystals into 1-D nanowires featuring a high density of grain boundaries, which then interconnect to form monolayer network structures extending into centimeter-scale size. Further investigation into the formation mechanism reveals that the initial emergence of NWN sheets occurs at the gas/liquid interfaces of the bubbles produced by sodium borohydride (NaBH4) during the synthesis process. Upon the rupture of these bubbles, an exocytosis-like process releases the Pt NWN sheets at the gas/liquid surface, which subsequently merge into a continuous monolayer Pt NWN sheet. The Pt NWN sheets exhibit outstanding oxygen reduction reaction (ORR) activities, with specific and mass activities 12.0 times and 21.2 times greater, respectively, than those of current state-of-the-art commercial Pt/C electrocatalysts.

7.
Nano Lett ; 19(6): 3730-3736, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31038977

RESUMO

We demonstrate the 2-D anisotropic formation of ultrathin free-floating Pt nanoplates from the assembly of small nanocrystals using T7 peptide (Ac-TLTTLTN-CONH2). As-formed nanoplates are rich in grain boundaries that can promote their catalytic activities. Furthermore, we demonstrate that a minor number of Pd atoms can selectively deposit on and stabilize the grain boundaries, which leads to enhanced structure stability. The Pd-enhanced Pt polycrystal nanoplates show great oxygen reduction reaction activities with 15.5 times higher specific activity and 13.7 times higher mass activity than current state-of-the-art commercial Pt/C electrocatalysts as well as 2.5 times higher mass activity for hydrogen evolution reaction compared with Pt/C.


Assuntos
Nanoestruturas/química , Oxigênio/química , Peptídeos/química , Platina/química , Catálise , Eletricidade , Modelos Moleculares , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanoestruturas/ultraestrutura , Oxirredução , Paládio/química
9.
J Am Heart Assoc ; 6(10)2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28963101

RESUMO

BACKGROUND: Exposure to psychosocial stress is a risk factor for cardiovascular disease, including vascular aging and regeneration. Given that dipeptidyl peptidase-4 (DPP4) regulates several intracellular signaling pathways associated with the glucagon-like peptide-1 (GLP-1) metabolism, we investigated the role of DPP4/GLP-1 axis in vascular senescence and ischemia-induced neovascularization in mice under chronic stress, with a special focus on adiponectin -mediated peroxisome proliferator activated receptor-γ/its co-activator 1α (PGC-1α) activation. METHODS AND RESULTS: Seven-week-old mice subjected to restraint stress for 4 weeks underwent ischemic surgery and were kept under immobilization stress conditions. Mice that underwent ischemic surgery alone served as controls. We demonstrated that stress impaired the recovery of the ischemic/normal blood-flow ratio throughout the follow-up period and capillary formation. On postoperative day 4, stressed mice showed the following: increased levels of plasma and ischemic muscle DPP4 and decreased levels of GLP-1 and adiponectin in plasma and phospho-AMP-activated protein kinase α (p-AMPKα), vascular endothelial growth factor, peroxisome proliferator activated receptor-γ, PGC-1α, and Sirt1 proteins and insulin receptor 1 and glucose transporter 4 genes in the ischemic tissues, vessels, and/or adipose tissues and numbers of circulating endothelial CD31+/c-Kit+ progenitor cells. Chronic stress accelerated aortic senescence and impaired aortic endothelial sprouting. DPP4 inhibition and GLP-1 receptor activation improved these changes; these benefits were abrogated by adiponectin blocking and genetic depletion. CONCLUSIONS: These results indicate that the DPP4/GLP-1-adiponectin axis is a novel therapeutic target for the treatment of vascular aging and cardiovascular disease under chronic stress conditions.


Assuntos
Adiponectina/metabolismo , Senescência Celular , Dipeptidil Peptidase 4/metabolismo , Células Progenitoras Endoteliais/enzimologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Isquemia/enzimologia , Neovascularização Fisiológica , Estresse Psicológico/enzimologia , Animais , Células Cultivadas , Doença Crônica , Dipeptidil Peptidase 4/deficiência , Dipeptidil Peptidase 4/genética , Modelos Animais de Doenças , Células Progenitoras Endoteliais/patologia , Isquemia/genética , Isquemia/patologia , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , PPAR gama/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteólise , Ratos Endogâmicos F344 , Ratos Transgênicos , Receptores de Adiponectina/metabolismo , Transdução de Sinais , Estresse Psicológico/genética , Estresse Psicológico/patologia , Estresse Psicológico/fisiopatologia , Fatores de Tempo , Técnicas de Cultura de Tecidos
10.
J Am Heart Assoc ; 6(7)2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28710180

RESUMO

BACKGROUND: DPP4 (Dipeptidyl peptidase-4)-GLP-1 (glucagon-like peptide-1) and its receptor (GLP-1R) axis has been involved in several intracellular signaling pathways. The Adrß3 (ß3-adrenergic receptor)/CXCL12 (C-X-C motif chemokine 12) signal was required for the hematopoiesis. We investigated the novel molecular requirements between DPP4-GLP-1/GLP-1 and Adrß3/CXCL12 signals in bone marrow (BM) hematopoietic stem cell (HSC) activation in response to chronic stress. METHODS AND RESULTS: Male 8-week-old mice were subjected to 4-week intermittent restrain stress and orally treated with vehicle or the DPP4 inhibitor anagliptin (30 mg/kg per day). Control mice were left undisturbed. The stress increased the blood and brain DPP4 levels, the plasma epinephrine and norepinephrine levels, and the BM niche cell Adrß3 expression, and it decreased the plasma GLP-1 levels and the brain GLP-1R and BM CXCL12 expressions. These changes were reversed by DPP4 inhibition. The stress activated BM sca-1highc-KithighCD48lowCD150high HSC proliferation, giving rise to high levels of blood leukocytes and monocytes. The stress-activated HSC proliferation was reversed by DPP4 depletion and by GLP-1R activation. Finally, the selective pharmacological blocking of Adrß3 mitigated HSC activation, accompanied by an improvement of CXCL12 gene expression in BM niche cells in response to chronic stress. CONCLUSIONS: These findings suggest that DPP4 can regulate chronic stress-induced BM HSC activation and inflammatory cell production via an Adrß3/CXCL12-dependent mechanism that is mediated by the GLP-1/GLP-1R axis, suggesting that the DPP4 inhibition or the GLP-1R stimulation may have applications for treating inflammatory diseases.


Assuntos
Encéfalo/enzimologia , Diferenciação Celular , Proliferação de Células , Dipeptidil Peptidase 4/metabolismo , Células-Tronco Hematopoéticas/enzimologia , Estresse Psicológico/enzimologia , Antagonistas de Receptores Adrenérgicos beta 3/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimiocina CXCL12/metabolismo , Doença Crônica , Dipeptidil Peptidase 4/deficiência , Dipeptidil Peptidase 4/genética , Inibidores da Dipeptidil Peptidase IV/farmacologia , Modelos Animais de Doenças , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Ratos Endogâmicos F344 , Ratos Transgênicos , Receptores Adrenérgicos beta 3/metabolismo , Restrição Física/psicologia , Transdução de Sinais , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/fisiopatologia , Estresse Psicológico/psicologia , Fatores de Tempo
11.
J Cachexia Sarcopenia Muscle ; 8(3): 370-385, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27897419

RESUMO

BACKGROUND: Exercise train (ET) stimulates muscle response in pathological conditions, including aging. The molecular mechanisms by which exercise improves impaired adiponectin/adiponectin receptor 1 (AdipoR1)-related muscle actions associated with aging are poorly understood. Here we observed that in a senescence-accelerated mouse prone 10 (SAMP10) model, long-term ET modulated muscle-regenerative actions. METHODS: 25-week-old male SAMP10 mice were randomly assigned to the control and the ET (45 min/time, 3/week) groups for 4 months. Mice that were maintained in a sedentary condition served controls. RESULTS: ET ameliorated aging-related muscle changes in microstructure, mitochondria, and performance. The amounts of proteins or mRNAs for p-AMPKα, p-Akt, p-ERK1/2, p-mTOR, Bcl-XL, p-FoxO3, peroxisome proliferators-activated receptor-γ coactivator, adiponectin receptor1 (adpoR1), and cytochrome c oxidase-IV, and the numbers of CD34+ /integrin-α7+ muscle stem cells (MuSCs) and proliferating cells in the muscles and bone-marrow were enhanced by ET, whereas the levels of p-GSK-3α and gp91phox proteins and apoptotic cells were reduced by ET. The ET also resulted in increased levels of plasma adiponectin and the numbers of bone-marrow (BM)-derived circulating CD34+ /integrin-α7+ MuSCs and their functions. Integrin-α7+ MuSCs of exercised mice had improved changes of those beneficial molecules. These ET-mediated aged muscle benefits were diminished by adiponectin and AdipoR1 blocking as well as AMPK inhibition. Finally, recombinant mouse adiponectin enhanced AMPK and mTOR phosphorylations in BM-derived integrin-α7+ cells. CONCLUSIONS: These findings suggest that ET can improve aging-related impairments of BM-derived MuSC regenerative capacity and muscle metabolic alterations via an AMPK-dependent mechanism that is mediated by an adiponectin/AdipoR1 axis in SAMP10 mice.


Assuntos
Adiponectina/metabolismo , Músculos/fisiologia , Mioblastos/metabolismo , Condicionamento Físico Animal , Receptores de Adiponectina/metabolismo , Regeneração , Animais , Biomarcadores , Peso Corporal , Movimento Celular , Citocinas/sangue , Lipídeos/sangue , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/metabolismo , Força Muscular , Músculo Esquelético/fisiologia , Receptores de Adiponectina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
12.
Arterioscler Thromb Vasc Biol ; 36(8): 1549-57, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27365406

RESUMO

OBJECTIVE: Cathepsin S (CatS) participates in atherogenesis through several putative mechanisms. The ability of cathepsins to modify histone tail is likely to contribute to stem cell development. Histone deacetylase 6 (HDAC6) is required in modulating the proliferation and migration of various types of cancer cells. Here, we investigated the cross talk between CatS and HADC6 in injury-related vascular repair in mice. APPROACH AND RESULTS: Ligation injury to the carotid artery in mice increased the CatS expression, and CatS-deficient mice showed reduced neointimal formation in injured arteries. CatS deficiency decreased the phosphorylation levels of p38 mitogen-activated protein kinase, Akt, and HDAC6 and toll-like receptor 2 expression in ligated arteries. The genetic or pharmacological inhibition of CatS also alleviated the increased phosphorylation of p38 mitogen-activated protein kinase, Akt, and HDAC6 induced by platelet-derived growth factor BB in cultured vascular smooth muscle cells (VSMCs), and p38 mitogen-activated protein kinase inhibition and Akt inhibition decreased the phospho-HDAC6 levels. Moreover, CatS inhibition caused decrease in the levels of the HDAC6 activity in VSMCs in response to platelet-derived growth factor BB. The HDAC6 inhibitor tubastatin A downregulated platelet-derived growth factor-induced VSMC proliferation and migration, whereas HDAC6 overexpression exerted the opposite effect. Tubastatin A also decreased the intimal VSMC proliferation and neointimal hyperplasia in response to injury. Toll-like receptor 2 silencing decreased the phosphorylation levels of p38 mitogen-activated protein kinase, Akt, and HDAC6 and VSMC migration and proliferation. CONCLUSIONS: This is the first report detailing cross-interaction between toll-like receptor 2-mediated CatS and HDAC6 during injury-related vascular repair. These data suggest that CatS/HDAC6 could be a potential therapeutic target for the control of vascular diseases that are involved in neointimal lesion formation.


Assuntos
Lesões das Artérias Carótidas/enzimologia , Artéria Carótida Primitiva/enzimologia , Catepsinas/metabolismo , Histona Desacetilases/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor 2 Toll-Like/metabolismo , Cicatrização , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/patologia , Artéria Carótida Primitiva/efeitos dos fármacos , Artéria Carótida Primitiva/patologia , Catepsinas/antagonistas & inibidores , Catepsinas/deficiência , Catepsinas/genética , Pontos de Checagem do Ciclo Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Genótipo , Desacetilase 6 de Histona , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Masculino , Camundongos Knockout , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/patologia , Neointima , Fenótipo , Fosforilação , Inibidores de Proteases/farmacologia , Interferência de RNA , Transdução de Sinais , Receptor 2 Toll-Like/genética , Transfecção , Remodelação Vascular , Cicatrização/efeitos dos fármacos
13.
PLoS One ; 10(8): e0136093, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26302400

RESUMO

Cysteinyl cathepsin K (CatK) is one of the most potent mammalian collagenases involved in cardiovascular disease. Here, we investigated the clinical predictive value of serum CatK levels in patients with chronic heart failure (CHF). We examined 134 patients with CHF, measuring their serum CatK, troponin I, high-sensitive C-reactive protein, and pre-operative N-terminal pro-brain natriuretic peptide levels. The patients were divided into two groups: the 44 patients who showed a left ventricular (LV) ejection fraction (LVEF) < 40% (the "lowLVEF" group) and the 90 patients showing LVEF values ≥ 40% (the "highLVEF" group). The lowLVEF patients had significantly higher serum CatK levels compared to the highLVEF patients (58.4 ± 12.2 vs. 44.7 ± 16.4, P < 0.001). Overall, a linear regression analysis showed that CatK levels correlated negatively with LVEF (r = -0.4, P < 0.001) and positively with LV end-diastolic dimensions (r = 0.2, P < 0.01), LV end-systolic dimensions (r = 0.3, P < 0.001), and left atrial diameters (r = 0.3, P < 0.01). A multiple logistic regression analysis showed that CatK levels were independent predictors of CHF (odds ratio, 0.90; 95% confidence interval, 0.84-0.95; P < 0.01). These data indicate that elevated levels of CatK are closely associated with the presence of CHF and that the measurement of circulating CatK provides a noninvasive method of documenting and monitoring the extent of cardiac remodeling and dysfunction in patients with CHF.


Assuntos
Catepsina K/sangue , Insuficiência Cardíaca/sangue , Hipertensão/sangue , Disfunção Ventricular Esquerda/sangue , Idoso , Proteína C-Reativa/metabolismo , Ecocardiografia , Matriz Extracelular/genética , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão/fisiopatologia , Lipoproteínas , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Análise de Regressão , Troponina I/sangue , Disfunção Ventricular Esquerda/fisiopatologia
14.
Int J Cardiol ; 183: 198-208, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25668148

RESUMO

BACKGROUND: Evidence from human and animal studies has demonstrated elevated levels of the cysteine protease cathepsin S (CatS) in hypoxic atherosclerotic lesions. We hypothesized that silencing of CatS gene would suppress ischemia-induced angiogenic action. METHODS AND RESULTS: Left femoral artery ligation-induced ischemia in mice showed the increased expression and activity of CatS in the ischemic muscle. The CatS-deficiency (CatS(-/-)) mice showed impaired functional recovery following hindlimb ischemia and reduced levels of peroxisome proliferator-activated receptor-γ (PPAR-γ), phospho-Akt (p-Akt), p-endothelial nitric oxide synthase, p-extracellular signal-regulated kinase1/2 (Erk1/2), p-p38 mitogen-activated protein kinase, and vascular endothelial growth factor (VEGF) proteins, as well as reduced levels of matrix metalloproteinase-9 and macrophage infiltration in the ischemic muscles. In vitro, CatS silencing reduced the levels of these targeted essential molecules for angiogenesis and vasculogenesis. Together, the results indicated that the effects of CatS knockdown led to defective endothelial cell invasion, proliferation, and tube formation. This notion was reinforced by the finding that CatS inhibition led to a decreased PPAR-γ level and VEGF/Erk1/2 signaling activation in response to ischemia. CatS(-/-) resulted in decreased circulating EPC-like CD31(+)/c-Kit(+) cells, accompanied by the reduction of the cellular levels of PPAR-γ, p-Akt, and VEGF induced by ischemic stress. Transplantation of bone-marrow-derived mononuclear cells from CatS(+/+) mice restored neovascularization in CatS(-/-) mice. CONCLUSIONS: CatS activity controls ischemia-induced neovascularization partially via the modulation of PPAR-γ and VEGF/Akt signaling activation.


Assuntos
Catepsinas/metabolismo , Isquemia/metabolismo , Músculo Esquelético/irrigação sanguínea , Animais , Células Endoteliais/citologia , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Artéria Femoral/citologia , Artéria Femoral/enzimologia , Artéria Femoral/metabolismo , Membro Posterior/irrigação sanguínea , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Neovascularização Patológica/enzimologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/citologia , Células-Tronco/enzimologia , Células-Tronco/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Nano Lett ; 13(2): 840-6, 2013 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-23320831

RESUMO

Surfactants with preferential adsorption to certain crystal facets have been widely employed to manipulate morphologies of colloidal nanocrystals, while mechanisms regarding the origin of facet selectivity remain an enigma. Similar questions exist in biomimetic syntheses concerning biomolecular recognition to materials and crystal surfaces. Here we present mechanistic studies on the molecular origin of the recognition toward platinum {111} facet. By manipulating the conformations and chemical compositions of a platinum {111} facet specific peptide, phenylalanine is identified as the dominant motif to differentiate {111} from other facets. The discovered recognition motif is extended to convert nonspecific peptides into {111} specific peptides. Further extension of this mechanism allows the rational design of small organic molecules that demonstrate preferential adsorption to the {111} facets of both platinum and rhodium nanocrystals. This work represents an advance in understanding the organic-inorganic interfacial interactions in colloidal systems and paves the way to rational and predictable nanostructure modulations for many applications.


Assuntos
Materiais Biomiméticos/química , Nanopartículas Metálicas/química , Peptídeos/química , Platina/química , Adsorção , Materiais Biomiméticos/síntese química , Modelos Moleculares , Tamanho da Partícula , Peptídeos/síntese química , Fenilalanina/química , Propriedades de Superfície
17.
Nanotechnology ; 21(49): 495602, 2010 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-21071820

RESUMO

One-pot hydrothermal process has been developed to synthesize uniform Te@phenol formaldehyde resin core-shell nanowires with unique fluorescent properties. A synergistic soft-hard template mechanism has been proposed to explain the formation of the core-shell nanowires. The Te@phenol formaldehyde resin core-shell nanowires display unique fluorescent properties, which give strong luminescent emission in the blue-violet and green regions with excitation wavelengths of 270 nm and 402 nm, respectively.


Assuntos
Materiais Biocompatíveis/síntese química , Formaldeído/síntese química , Nanotecnologia/métodos , Nanofios/química , Tamanho da Partícula , Fenóis/síntese química , Polímeros/síntese química , Materiais Biocompatíveis/química , Sobrevivência Celular , Células HeLa , Humanos , Microscopia de Fluorescência , Nanopartículas/química , Nanofios/ultraestrutura , Espectroscopia Fotoeletrônica , Telúrio , Temperatura , Difração de Raios X
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