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1.
Int J Biol Macromol ; 268(Pt 1): 131744, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38663711

RESUMO

Herpetrione(HPE) is an effective compound that has been used in the treatment of liver diseases. To improve its dissolution and absorption, herpetrione nanosuspensions was prepared. Nanosuspensions were proved to achieve intact absorption in vivo. However, the transport mechanisms are not fully understood, especially lack of direct evidence of translocation of particulates. In this study, an environment-responsive dye, P4, was loaded into herpetrione amorphous nanoparticles (HPE-ANPs) to elucidate the absorption and transport mechanism of the nanoparticles. And the amount of HPE and nanoparticles in the samples were quantified using HPLC/LC-MS/MS and IVIS with the model of Caco-2 and Caco-2/HT29-MTX. Results demonstrated that HPE is mainly taken up by passive diffusion in the form of free drugs, while HPE-ANPs are internalized by an energy dependent active transport pathway or intracellular endocytosis. It is speculated that HPE-ANPs may change the original entry pathway of drug molecules. Furthermore, the presence of mucus layer and the use of HPMC E15 may contribute to drug absorption to some extent. Transcellular transport study indicates that HPE-ANPs has a poor absorption. In conclusion, the differences in the absorption behavior trends of HPE-ANPs are caused by the difference in particle properties and the form of existence of the drug.

2.
Int J Cardiol ; 401: 131782, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38246423

RESUMO

BACKGROUND AND AIMS: Coronary heart disease (CHD) is a condition that carries a high risk of mortality and is associated with aging. CHD is characterized by the chronic inflammatory response of the coronary intima. Recent studies have shown that the methylation level of blood mononuclear cell DNA is closely associated with adverse events in CHD, but the roles and mechanisms of DNA methylation in CHD remain elusive. METHODS AND RESULTS: In this study, the DNA methylation status within the epigenome of human coronary tissue in the sudden coronary death (SCD) group and control (CON) group of coronary heart disease was analyzed using the Illumina® Infinium Methylation EPIC BeadChip (850 K chip), resulting in the identification of a total of 2553 differentially methylated genes (DMGs). The differentially methylated genes were then subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and significant differential DNA methylation was found. Among the differentially hypomethylated genes were GAL-8, LTF, and RFPL3, while the highly methylated genes were TMEM9B, ANK3, and C6orF48. These genes were mainly enriched in 10 significantly enriched pathways, such as cell adhesion junctions, among which the differentially methylated gene GAL-8 was involved in inflammatory pathway signaling. For functional analysis of GAL-8, we first examined the differences in GAL-8 promoter methylation levels among different subgroups of human coronary tissue in the CON, CHD, and SCD groups using pyrophosphate sequencing. The results revealed reduced GAL-8 promoter methylation levels in the SCD group, while the difference between the CHD and CON groups was not statistically significant (P > 0.05). The reduced GAL-8 promoter methylation level was associated with upregulated GAL-8 expression, which led to increased expression of the inflammatory markers TNF-α, IL-1ß, MCP-1, MIP-2, MMP-2, and MMP-9. This enhanced inflammatory response contributed to the accumulation of foam cells, thickening of the intima of human coronary arteries, and increased luminal stenosis, which promoted the occurrence of sudden coronary death. Next, we found that GAL-8 promoter methylation levels in PBMC were consistent with human coronary tissue. The unstable angina group (UAP) had significantly lower GAL-8 promoter methylation levels than stable angina (SAP) and healthy controls (CON) (P < 0.05), and there was a significant correlation between reduced GAL-8 promoter methylation levels and risk factors for coronary heart disease. These findings highlight the association between decreased GAL-8 promoter methylation and the presence of coronary heart disease risk factors. ROC curve analysis suggests that methylation of the GAL 8 promoter region is an independent risk factor for CHD. In conclusion, our study confirmed differential expression of GAL-8, LTF, MUC4D, TMEM9B, MYOM2, and ANK3 genes due to DNA methylation in the SCD group. We also established the consistency of GAL-8 promoter methylation alterations between human coronary tissue and patient peripheral blood monocytes. The decreased methylation level of the GAL-8 promoter may be related to the increased expression of GAL-8 and the coronary risk factors. CONCLUSIONS: Accordingly, we hypothesized that reduced levels of GAL-8 promoter methylation may be an independent risk factor for adverse events in coronary heart disease.


Assuntos
Doença das Coronárias , Leucócitos Mononucleares , Humanos , Metilação de DNA/genética , Doença das Coronárias/diagnóstico , Doença das Coronárias/genética , Doença das Coronárias/epidemiologia , Regiões Promotoras Genéticas/genética , Inflamação/genética , Proteínas de Transporte/genética
3.
Int J Cardiol ; 392: 131303, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37652272

RESUMO

OBJECTIVE: Autophagy is important in regulating inflammation and cholesterol efflux, suggesting that targeting autophagy may slow down atherosclerosis (AS). Since the pathological basis of coronary artery disease (CAD) is atherosclerosis, it is crucial to investigate the role of autophagy in atherosclerosis. This study aimed to investigate the role of the chemokine CXC chemokine receptor 4 (CXCR4) in promoting macrophage autophagy through the phosphoinositide-3 kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway to alleviate coronary artery disease. METHODS: The human left coronary artery and myocardium were collected to detect CXCR4, MAP1LC3(LC3) and SQSTM1(p62) expression. ApoE-/- mice were used to establish an atherosclerosis mice model, while human monocytes (THP-1) were used to establish a foam cell model and co-cultured with foam cells using siRNACXCR4. Western blotting was conducted to quantify CXCR4, PI3K/AKT/mTOR pathway protein, LC3, Beclin1 and p62 protein levels. The left coronary artery from humans and mouse aorta and myocardium were stained with Hematoxylin and Eosin (H&E), macrophages with Oil Red O staining and foam cells were assessed by Movat's staining. CXCR4 levels, PI3K/AKT/mTOR pathway protein, LC3 and p62 were detected by immunohistochemistry (IHC) and immunofluorescence assays. Detection of autophagosomes in macrophages using transmission electron microscopy. We further assessed whether the effect of CXCR4-mediated macrophage autophagy on the formation of atherosclerosis and structural changes in the myocardium was mediated via the PI3K/AKT/mTOR signaling pathway. RESULTS: CXCR4 and p62 proteins were upregulated in human coronary lesions, mouse aorta, myocardial tissue, and foam cells, while LC3II/LC3I was downregulated. p85 (P-PI3K), Ser473 (P-AKT), and Ser2448 (P-mTOR) phosphorylated proteins associated with the PI3K/AKT/mTOR pathway were detected in AS and foam cell models. Upregulated CXCR4 inhibited autophagy of macrophages and increased the severity of atherosclerotic lesions. After specific knockdown of CXCR4 by adeno-associated virus (AAV9-CXCR4-RNAi) and siRNACXCR4, the above indicators were reversed, macrophage autophagy was promoted, the severity of atherosclerotic lesions was reduced, and the disorganized arrangement of myocardial architecture was improved. CONCLUSION: Knockdown of CXCR4 reduces the extent of coronary artery disease by promoting macrophage autophagy through the PI3K/AKT/mTOR pathway to attenuate atherosclerosis.

4.
Zhongguo Zhong Yao Za Zhi ; 48(8): 2116-2125, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37282900

RESUMO

This study aims to separate and characterize self-assembled nanoparticles(SAN) from Shaoyao Gancao Decoction(SGD) and determine the content of active compounds. Further, we aimed to observe the therapeutic effect of SGD-SAN on imiquimod-induced psoriasis in mice. The separation of SGD was performed by dialysis, and the separation process was optimized by single factor experiment. The SGD-SAN isolated under the optimal process was characterized, and the content of gallic acid, albiflorin, paeoniflorin, liquiritin, isoliquiritin apioside, isoliquiritin, and glycyrrhizic acid in each part of SGD was determined by HPLC. In the animal experiment, mice were assigned into a normal group, a model group, a methotrexate group(0.001 g·kg~(-1)), and SGD, SGD sediment, SGD dialysate, and SGD-SAN groups of different doses(1, 2, and 4 g·kg~(-1)) respectively. The psoriasis grade of mice was evaluated based on the pathological changes of skin lesions, the content of inflammatory cytokines, organ index and other indicators. The results showed that SAN obtained by centrifugation at 13 000 r·min~(-1) for 30 min was stable after dialysis for 4 times, which were uniform spherical nanoparticles with the particle size of(164.43±1.34) nm, the polydispersity index of(0.28±0.05), and the Zeta potential of(-12.35±0.80) mV. The active compound content accounted for more than 70% of SGD. Compared with the model group, SAN and SGD decreased the skin lesion score, spleen index, and inflammatory cytokine levels(P<0.05 or P<0.01) and alleviated the skin thickening and infiltration of inflammatory cells. However, the sediment group and the dialysate group had no obvious effect. SGD showed a good therapeutic effect on imiquimod-induced psoriasis in mice, and SAN demonstrated the effect equivalent to SGD in a dose-dependent manner. Therefore, we conclude that the SAN formed during decocting is the main active form of SGD, which can lower the levels of inflammatory cytokines, promote the normal differentiation of keratinocytes, and reduce the infiltration of inflammatory cells in the treatment of psoriasis lesions in mice.


Assuntos
Medicamentos de Ervas Chinesas , Camundongos , Animais , Imiquimode , Medicamentos de Ervas Chinesas/farmacologia , Ácido Glicirrízico , Cromatografia Líquida de Alta Pressão/métodos
5.
Int J Cardiol ; 376: 115-124, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36716974

RESUMO

OBJECTIVE: The study aims to investigate the effect of developmental endothelial locus-1(DEL-1) expression in atherosclerotic plaque formation and its mechanism. METHODS: Human left coronary arteries were collected to detect the DEL-1 expression. The ApoE-/- mice were used to establish the atherosclerosis mice model. The left coronary artery and mouse aorta were stained with HE, Oil Red O, and Movat staining. The DEL-1 levels, chemokines CXC chemokine receptor 4 (CXCR4) and its ligand stromal cell-derived factor-1alpha (SDF-1α), pathway protein glycogen synthase kinase-3ß (GSK-3ß), CCAAT enhanced binding protein ß (C/EBPß), and downstream inflammatory factors (C-X-C motif chemokine 2 (MIP-2or CXCL2), macrophage inflammatory protein-1alpha (MIP-1α or CCL3),Tumor Necrosis Factor alpha (TNF-α) were detected by immunoblotting and immunohistochemistry. Pearson correlation coefficient was used to analyze the correlation between DEL-1 gene expression and inflammatory factors in the lesion group and the correlation between DEL-1 gene expression and structure-related indexes. RESULTS: Compared with Control group(CON), the intravascular plaque area was widened, accompanied by narrowed lumens. The number of plaque foam cells was significantly increased in the high fat and high cholesterol (AS group) or AAV9-eGFP group (P < 0.05). Compared to CON, the enhanced fluorescence intensity of DEL-1 with CD68 in the AS or AAV9-eGFP groups. Diminished fluorescence of DEL-1 with CD68 expression in AAV9-CXCR4 group compared to AS group or AAV9-eGFP group. The DEL-1 and its downstream proteins in AS group or AAV9-eGFP group were mainly accumulated in the macrophage cytoplasm. The DEL-1 expression level was significantly and positively correlated with plaque area, lumen stenosis, plaque foam cell count, TNFα, CXCL2, and CCL3 levels. CONCLUSION: DEL-1 inhibition decreases macrophagic inflammatory factors involved in atherosclerotic plaque formation.


Assuntos
Aterosclerose , Placa Aterosclerótica , Camundongos , Humanos , Animais , Placa Aterosclerótica/metabolismo , Glicogênio Sintase Quinase 3 beta , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/farmacologia , Camundongos Knockout para ApoE , Aterosclerose/metabolismo , Transdução de Sinais , Macrófagos/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
6.
Obesity (Silver Spring) ; 30(2): 447-459, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35088561

RESUMO

OBJECTIVE: The aim of this study was to research the role and underlying mechanism of miR-195 involved in pancreatic ß-cell dedifferentiation induced by hyperlipemia in type 2 diabetes mellitus. METHODS: High-fat-diet-induced obese C57BL/6J mice and palmitate-stimulated Min6 cells were used as the models of ß-cell dedifferentiation in vivo and in vitro, respectively. The expression of miR-195 and insulin secretion during ß-cell dedifferentiation were measured. Also, the influence of regulated miR-195 expression on ß-cell dedifferentiation was examined. Meanwhile, the IRS-1/2/Pi3k/Akt pathway and mitofusin-2 (Mfn2) expression were investigated during ß-cell dedifferentiation. RESULTS: MiR-195 was upregulated during lipotoxicity-induced ß-cell dedifferentiation in both in vivo and in vitro experiments, and miR-195 functionally contributed to lipotoxicity-induced ß-cell dedifferentiation. Furthermore, miR-195 inhibited IRS-1/2/Pi3k/Akt pathway activation, which accompanied ß-cell dedifferentiation. Mfn2, a target of miR-195, was found to be downregulated and was associated with increased mitochondrial production of reactive oxygen species during ß-cell dedifferentiation. Instructively, inhibition of miR-195, at least partially, reversed the downregulation of Mfn2, restored IRS-1/2/Pi3k/Akt pathway activation, and prevented ß-cell dedifferentiation. CONCLUSIONS: MiR-195 promoted ß-cell dedifferentiation through negatively regulating Mfn2 expression and inhibiting the IRS-1/2/Pi3k/Akt pathway, providing a promising treatment for type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2 , MicroRNAs , Animais , Desdiferenciação Celular , Diabetes Mellitus Tipo 2/genética , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
7.
IUBMB Life ; 72(3): 465-475, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31828927

RESUMO

Glioma, like most cancers, possesses a unique bioenergetic state of aerobic glycolysis known as the Warburg effect, which is a dominant phenotype of most tumor cells. Glioma tumors exhibit high glycolytic metabolism with increased lactate production. Data derived from the gene expression profiling interactive analysis (GEPIA) database show that pyruvate dehydrogenase kinase 1 (PDK1) is significantly highly expressed in glioma tissues compared with corresponding normal tissues. PDK1 is a key enzyme in the transition of glycolysis to tricarboxylic acid cycle, via inactivating PDH and converting oxidative phosphorylation to Warburg effect, resulting in increment of lactate production. Silencing of PDK1 expression resulted in reduced lactate and ATP, accumulation of ROS, mitochondrial damage, decreased cell growth, and increased cell apoptosis. Aberrant expression of miR-128 has been observed in many human malignancies. Mechanistically, we discover that overexpressed miR-128-3p disturbs the Warburg effect in glioma cells via reducing PDK1. Our experiments confirmed that the miR-128-3p/PDK1 axis played a pivotal role in cancer cell metabolism and growth. Collectively, these findings suggest that therapeutic strategies to modulate the Warburg effect, such as targeting of PDK1, might act as a potential therapeutic target for glioma treatment.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , MicroRNAs/genética , Mitocôndrias/patologia , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética , Trifosfato de Adenosina/metabolismo , Apoptose/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioma/patologia , Humanos , Ácido Láctico/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Espécies Reativas de Oxigênio/metabolismo
8.
Cell Stress Chaperones ; 24(1): 91-104, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30374881

RESUMO

Olfactory ensheathing glia (OEG) play an important role in regulating the regeneration of an injured nervous system. However, chronic inflammation damage reduces the viability of OEG via poorly understood mechanisms. We aimed to investigate the pathological responses of OEG in response to LPS-mediated inflammation stress in vitro. The results indicated that lipopolysaccharide (LPS) treatment significantly reduced the viability of OEG in a dose-dependent fashion. Mechanistically, LPS stimuli induced mitochondrial oxidative damage, mitochondrial fragmentation, mitochondrial metabolism disruption, and mitochondrial apoptosis activation. Furthermore, we verified that LPS modulated mitochondrial apoptosis by promoting Bax upregulation, and this process was regulated by the JNK-Bnip3 pathway. Inhibition of the JNK-Bnip3 pathway prevented LPS-mediated Bax activation, thus attenuating OEG apoptosis. Altogether, our data illustrated that LPS-mediated inflammation injury evoked mitochondrial abnormalities in OEG damage via the JNK-Bnip3-Bax pathway. This finding provides a potential target to protect OEG against chronic inflammation stress.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lipopolissacarídeos/farmacologia , Proteínas de Membrana/metabolismo , Mitocôndrias/patologia , Neuroglia/patologia , Bulbo Olfatório/patologia , Proteínas Proto-Oncogênicas/metabolismo , Proteína X Associada a bcl-2/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Serina Peptidase 2 de Requerimento de Alta Temperatura A/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neuroglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
9.
Appl Opt ; 54(4): 717-20, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25967779

RESUMO

We presented the first demonstration of a high-peak power few-nanosecond pulse 1342-nm Nd:YVO(4) laser by the combination of cavity dumping and in-band pumping. The maximum average output power of 3.2 W with Gaussian TEM(00) mode was obtained at the pulse repetition rate (PRR) of 10 kHz. The pulse width remained to be 4.7±0.1 ns for the PRR from 2 to 10 kHz. The maximum pulse energy of 0.55 mJ was obtained at 2 kHz and the corresponding peak power was up to 117 kW. This is, to our knowledge, the shortest ns pulse width and the highest peak power for LD-pumped 1.3 µm TEM(00) lasers with an active Q-switch device.

10.
J Stroke Cerebrovasc Dis ; 23(10): 2591-2597, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25267587

RESUMO

This study aimed to investigate the combination effects of bone marrow stromal cells (BMSCs) and oxiracetam for ischemic stroke. Forty Sprague Dawley female rats (220 ± 20 g) were subjected to a 2-hour ischemic middle cerebral artery occlusion (MCAO)-24 hours reperfusion model. The rats were randomly divided into 4 groups. Rats from BMSCs group, oxiracetam group, and BMSCs + oxiracetam group accepted injection of BMSCs (3 × 10(6) cells), oxiracetam (800 mg/kg), and BMSCs + oxiracetam, respectively. Rats from control group did not receive any interventions after ischemia reperfusion. The neurologic function was examined by modified neurological severity scores (mNSS). B-cell lymphoma 2 (Bcl-2) expression and apoptosis were detected by immunohistochemistry and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. The mNSS was decreased in all treatment groups and that in BMSCs + oxiracetam group was lower than BMSCs group and oxiracetam group (P < .05). The expression of Bcl-2 was unregulated in all treatment groups (P < .05), and similarly, the expression of Bcl-2 in BMSCs + oxiracetam group was higher than BMSCs group and oxiracetam group (P < .05). Control group displayed more TUNEL-positive cells than the treatment groups, and BMSCs + oxiracetam group displayed less apoptotic cells than BMSCs group or oxiracetam group (P < .05). Transplantation of BMSCs can promote the recovery of neurologic function in MCAO rats, and the effect of BMSCs combined with oxiracetam was better than the either one. Upregulation of Bcl-2 resulting in a decrease of apoptosis may be one of the mechanisms of BMSCs treatment for cerebral ischemic stroke.


Assuntos
Células da Medula Óssea/citologia , Transplante de Medula Óssea/métodos , Isquemia Encefálica/terapia , Células-Tronco Mesenquimais/metabolismo , Pirrolidinas/farmacologia , Acidente Vascular Cerebral/terapia , Animais , Células da Medula Óssea/metabolismo , Isquemia Encefálica/metabolismo , Terapia Combinada/métodos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Células-Tronco Mesenquimais/citologia , Nootrópicos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirrolidinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/metabolismo , Resultado do Tratamento , Regulação para Cima/efeitos dos fármacos
11.
Neurosci Bull ; 30(3): 524-34, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24817388

RESUMO

Cerebral ischemia remains the most frequent cause of death and quality-of-life impairments due to neurological deficits, and accounts for the majority of total healthcare costs. However, treatments for cerebral ischemia are limited. Over the last decade, bone marrow stromal cell (BMSC) therapy has emerged as a particularly appealing option, as it is possible to help patients even when initiated days or even weeks after the ischemic insult. BMSCs are a class of multipotent, self-renewing cells that give rise to differentiated progeny when implanted into appropriate tissues. Therapeutic effects of BMSC treatment for ischemic stroke, including sensory and motor recovery, have been reported in pre-clinical studies and clinical trials. In this article, we review the recent progress in BMSC-based therapy for ischemic stroke, focusing on the route of delivery and pre-processing of BMSCs. Selecting an optimal delivery route is of particular importance. The ideal approach, as well as the least risky, for translational applications still requires further identification. Appropriate preprocessing of BMSCs or combination therapy has the benefit of achieving the maximum possible restoration. Further pre-clinical studies are required to determine the time-window for transplantation and the appropriate dosage of cells.


Assuntos
Isquemia/complicações , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Animais , Humanos
12.
Opt Lett ; 39(7): 1965-7, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686650

RESUMO

Continuous wave 808 nm pump laser-induced thermal damage of polycrystalline transparent ceramic and crystalline Nd:YAG materials was investigated both experimentally and theoretically. The measured temperature agrees well with the theoretical simulation, and the maximum hoop stresses occur on the incident facet of the end-pumped rod at about √2 times of the pump beam radius w0, where the temperature gradient is the highest and the damage occurs first at this location. The fracture-limited laser intensity of ceramics was experimentally measured to be 6.4±0.6 kW/cm2, nearly 64% higher than that of the crystals (3.9±0.3 kW/cm2). The deduced thermal fracture stress for ceramic was 386±50 MPa, which is 64% higher than that of the crystals (235±16 MPa).

13.
J Mol Neurosci ; 52(2): 177-85, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24048741

RESUMO

Cerebral ischemia is a major cause of morbidity and mortality in the aged population, as well as a tremendous burden on the healthcare system. Despite timely treatment with thrombolysis and percutaneous intravascular interventions, many patients are often left with irreversible neurological deficits. Bone marrow stromal cells (BMSCs), also referred to as mesenchymal stem cells (MSCs), are a type of nonhematopoietic stem cells which exists in bone marrow mesh, with the potential to self-renew. Unlike cells in the central nervous system, BMSCs differentiate not only into mesodermal cells, but also endodermal and ectodermal cells. Moreover, it has been reported that BMSCs develop into cells with neural and vascular markers and play a role in recovery from ischemic stroke. These findings have fuelled excitement in regenerative medicine for neurological diseases, especially for ischemic stroke. There is now preclinical evidence to suggest that BMSCs grafted into the brain of ischemic models abrogate neurological deficits. Based on the overwhelming evidence from animal studies as well as in clinical trials, BMSC transplantation is considered a promising strategy for treatment of ischemic stroke. The goal of this review is to present an integrated consideration of molecular mechanisms in a chronological fashion and discuss an optimal BMSC delivery route for ischemic stroke.


Assuntos
Isquemia Encefálica/terapia , Transplante de Células-Tronco Mesenquimais , Acidente Vascular Cerebral/terapia , Animais , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo
14.
Appl Opt ; 52(31): 7494-7, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24216648

RESUMO

We report a high-power diode-laser (LD) side-pumped rod Tm:YAG laser of around 2 µm. The laser was water-cooled at 8°C and yielded a maximum output power of 267 W at 2.07 µm, which is the highest output power for an all solid-state cw 2.07 µm rod Tm:YAG laser reported as far as we know. The corresponding optical-optical conversion efficiency was 20.7%, and the slope efficiency was about 29.8%, respectively.


Assuntos
Lasers de Estado Sólido , Túlio , Desenho de Equipamento , Análise de Falha de Equipamento
15.
Opt Lett ; 38(19): 3903-5, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24081084

RESUMO

A high efficiency and high peak power picosecond (ps) mid-infrared optical parametric amplifier with a new nonlinear crystal BaGa(4)Se(7) pumped by a 30 ps 1064 nm Nd:YAG laser is demonstrated for the first time. The maximum photon conversion efficiency of 56% from 1064 nm to 3.9 µm idler has been achieved at the pump energy of ~1.8 mJ. A maximum idler output of 830 µJ at 3.9 µm with peak power of ~27 MW was obtained at pump energy of ~9.1 mJ. Moreover, a 3-5 µm idler tuning range was demonstrated, with output energies of ~300 µJ at 5 µm and up to 1 mJ at 3 µm at ~8.2 mJ pump energy.

16.
Opt Lett ; 37(12): 2403-5, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22739922

RESUMO

We demonstrate a high-power UV 278 nm laser by fourth-harmonic generation (FHG) of a 1112 nm Nd:YAG laser in a nonlinear optical (NLO) crystal CsB3O5 (CBO) for the first time, to our best knowledge. A 30 W level diode-pumped Q-switched Nd:YAG laser at 1112 nm with beam quality factor M2=1.2 was used as the fundamental light source at a pulse width of 500 ns. With an LiB3O5 crystal, the 1112 nm laser was first frequency-doubled to 556 nm with an average output power of 13.5 W. It was then frequency doubled again in a CBO crystal to obtain the FHG output at 278 nm. The maximum average output power of the 278 nm laser is up to 1.5 W. The results demonstrated that CBO crystal is a promising NLO material for UV high-power lasers below 300 nm.


Assuntos
Compostos de Boro/química , Césio/química , Lasers de Estado Sólido , Óxidos/química , Raios Ultravioleta , Análise Espectral
17.
Opt Lett ; 36(8): 1485-7, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21499398

RESUMO

A high-power 880-nm diode-directly-pumped passively mode-locked 1342 nm Nd:YVO4 laser was demonstrated with a semiconductor saturable absorber mirror (SESAM). The laser mode radii in the laser crystal and on the SESAM were optimized carefully using the ABCD matrix formalism. An average output power of 2.3 W was obtained with a repetition rate of 76 MHz and a pulse width of 29.2 ps under an absorbed pump power of 12.1 W, corresponding to an optical-optical efficiency of 19.0% and a slope efficiency of 23.9%, respectively.

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