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1.
J Colloid Interface Sci ; 559: 206-214, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629274

RESUMO

Controllable synthesis of multimetal nanocrystals with hierarchical structures and tunable compositions are feasible to steeply improve the catalytic properties in fuel cells. Herein, trimetallic PtRhCo petal-assembled alloyed nanoflowers (PtRhCo PAANFs) were fabricated via a one-pot solvothermal method, which showed remarkable enlargement in specific activity and mass activity over PtRh0.25Co nanodentrites (NDs), PtRh1.5Co NDs, PtCo NDs and commercial Pt/C catalysts for ethylene glycol oxidation in 0.5 M KOH solution. The as-developed catalyst exhibited dramatically better CO tolerance and recoverability, coupling with the superior activity and durability for hydrogen evolution reaction (HER) in the alkaline electrolyte. This work demonstrates the significance of Rh in the alloy for improving the stability. This work offers a promising strategy for preparation of advanced trimetallic electrocatalysts for energy conversion applications.

2.
J Colloid Interface Sci ; 560: 467-474, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31676129

RESUMO

Developing highly active and durable catalyst is of pivotal importance in fuel cells, owing to excessive consumption of fossil fuels. Herein, porous dendritic PtRuPd nanospheres (PtRuPd NSs) were synthesized by a facile hexadecylpyridinium chloride (HDPC)-mediated one-pot aqueous method with ascorbic acid (AA) as the reducing agent. The as-obtained PtRuPd NSs displayed high-efficient catalytic activity and durability for ethylene glycol oxidation reaction (EGOR) and oxygen reduction reaction (ORR). It exhibited enlarged mass activity (MA, 1.368 A mg-1) compared to commercial Pt/C (1.100 A mg-1) for EGOR. Besides, the onset potential (Eonset, 0.930 V) and half-wave potential (E1/2, 0.852 V) of PtRuPd NSs were more positive relative to homemade PtPd NSs (0.905 and 0.840 V), PdRu NSs (0.895 and 0.839 V), and commercial Pt/C (0.910 and 0.822 V) toward ORR. This work provides some valuable guidelines for producing novel trimetallic nanocatalysts in fuel cells.

3.
Transl Lung Cancer Res ; 8(6): 787-796, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32010557

RESUMO

BACKGROUND: Transbronchial lung biopsy is an important approach to diagnose peripheral lung cancer, but bronchoscopy based treatment options are limited and poorly studied. A flexible bronchoscopy-guided water-cooled microwave ablation (MWA) catheter was developed to evaluate the feasibility and safety both in ex vivo and in vivo porcine models. METHODS: Using direct penetration of the catheter through the surface of ex vivo porcine lung, ablations (n=9) were performed at 70, 80, 90 W for 10 minutes. Temperatures of the catheter and 10, 15, 20 mm away from the tip were measured. Under bronchoscopy conditions in porcine lung, ablations (n=18, 6 in ex vivo and 12 in vivo) were performed at 80 W for 5 minutes. Computed tomography (CT) was acquired perioperative, 24 hours, 2 weeks, and 4 weeks post ablation. Ablation zones were excised at 24 hours and 4 weeks respectively. Long-axis diameter (Dl) and short-axis diameter (Ds) were measured and tissues were sectioned for pathological examination. RESULTS: In-ex vivo lung, the temperature at 20 mm removed was over 60 °C at 80 W for 288±26 seconds. The ablations under bronchoscopic conditions were successful in-ex vivo and in vivo lung. No complications occurred during the procedures. Coagulation necrosis was visible at 24 hours, and repaired fibrous tissue was seen at 4 weeks. CONCLUSIONS: The flexible bronchoscopy-guided water-cooled MWA is feasible and safe. This early animal data holds promise of MWA becoming a potential therapeutic tool for Peripheral Lung Cancers.

4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 34(7): 682-5, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24257168

RESUMO

OBJECTIVE: To understand the current status and relevant factors influencing the duration of breastfeeding in rural areas in China. METHODS: Children under two years old were selected as subjects from the study on "Physical growth among the under 7-years-old children from the rural areas of ten provinces in China in 2006". Kaplan-Meier method was used to estimate the survival curves and Cox multivariate stepwise regression was used to identify the relevant factors on the duration of breastfeeding. RESULTS: Median of the duration for breastfeeding was 12 months in rural areas of 10 provinces in China. Results of this study suggested that factors as sex, birth order, areas of residency, nationality, initiation of formula, parents' education levels, maternal services and family income were correlated with the duration of breastfeeding. CONCLUSION: Duration of breastfeeding among rural children under 2-years of age was short in the 10 provinces of China. Factors as level of education, residential areas and family income of the parents as well as sex of the children were correlated with the duration of breastfeeding. Intervention program should be implemented to improve the current status on breastfeeding.


Assuntos
Aleitamento Materno , Fatores Epidemiológicos , Adulto , Pré-Escolar , China/epidemiologia , Família , Feminino , Humanos , Renda , Masculino , Pais , População Rural
5.
J Transl Med ; 11: 245, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24090193

RESUMO

BACKGROUND: Protein Tyrosine Phosphatase Receptor-type O (PTPRO) has recently been in the spotlight as a tumor suppressor, whose encoding gene is frequently methylated in cancers. We examined the methylation status of the PTPRO gene promoter in breast cancer and evaluated the correlation between PTPRO promoter methylation and both clinicopathological parameters and prognosis of breast cancer patients. METHODS: Two hundred twenty-one formalin-fixed, paraffin-embedded (FFPE) tumor tissues, 20 FFPE normal adjacent tissues and 24 matched plasma samples, collected from primary breast cancer patients, were assessed for PTPRO gene promoter methylation using methylation-specific PCR. Associations of promoter methylation with clinicopathological parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect on survival. RESULTS: 175 samples gave identifiable PCR products, of which 130 cases (74.3%) had PTPRO gene promoter methylation. PTPRO methylation correlated with higher histological grade (P = 0.028), but not other clinical parameters. Multivariate analysis indicated that overall survival (OS) was significantly poorer in HER2-positive, but not ER-positive patients with methylated-PTPRO. Methylated-PTPRO was detectable in matched plasma samples and only observed in plasma from patients whose corresponding primary tumors were also methylated. CONCLUSIONS: PTPRO methylation is a common event in the primary breast cancer and can be reliably detected in peripheral blood samples. PTPRO methylation is associated with poor survival only in HER2-positive patients, suggesting use of PTPRO methylation as a prognostic factor for breast cancer and for optimizing individualized therapy for HER2-positive patients.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Metilação de DNA/genética , Medicina de Precisão , Regiões Promotoras Genéticas , Receptor ErbB-2/metabolismo , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Análise Multivariada , Inclusão em Parafina , Prognóstico , Modelos de Riscos Proporcionais , Fixação de Tecidos , Resultado do Tratamento , Adulto Jovem
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(2): 131-4, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22575128

RESUMO

OBJECTIVE: To analysis the influencing factors on underweight and stunting among children aged 0 - 3 years in rural areas from ten provinces in China. METHODS: Children under study were identified by multi-stage stratified cluster from rural areas of ten provinces in China. The ascertainment methods mainly included questionnaire and anthropometric measurements. RESULTS: There were 58 926 children under investigation, with 50.91% were boys. The overall rates on underweight and stunting were 5.05% and 10.49% respectively. The rate in the 6 month-olds (1.97%, 3.79%) was the lowest, while the highest were in the 24 month-olds (7.80%) and the 36 month-olds (16.83%). Age, sex, birth weight, gestational weeks as well as maternal education and fathers' schooling were factors significantly related to childhood underweight and stunting (P < 0.0001). CONCLUSION: The status of underweight and stunting among children aged 0 - 3 years in rural areas was impressive, with birth weight was the key factor influencing the growth of children. Perinatal health care should be improved to promote the growth of children.


Assuntos
Desenvolvimento Infantil , Transtornos do Crescimento/epidemiologia , Magreza/epidemiologia , Peso ao Nascer , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Masculino , População Rural
7.
Cancer Lett ; 315(2): 138-44, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22099875

RESUMO

Epigenetic inactivation of protein tyrosine phosphatase receptor-type O (PTPRO), a new member of the PTP family, has been described in several forms of cancer. We evaluated PTPRO promoter hypermethylation as a potential biomarker in esophageal squamous cell carcinoma (ESCC). This alteration was observed in 27 (75%) of 36 primary tumors and correlated significantly with depth of invasion (T-stage, P = 0.013). Among matched peripheral blood samples from ESCC patients, 13 (36.1%) of 36 exhibited detectable methylated PTPRO in plasma, while 15 (41.7%) of 36 had this abnormality in buffy coat. No methylated PTPRO was observed in normal peripheral blood samples from 10 healthy individuals. In addition, demethylation by 5-aza-dC treatment led to gene reactivation in PTPRO-methylated and -silenced ESCC cell lines. To our knowledge, this is the first report of methylated PTPRO as a noninvasive tumor biomarker in peripheral blood. These findings suggest that hypermethylated PTPRO occurs frequently in ESCC. Further, detection in peripheral blood of ESCC patients suggests potential clinical application for noninvasive diagnosis and disease monitoring.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/fisiopatologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/fisiopatologia , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores , Carcinoma de Células Escamosas/enzimologia , Linhagem Celular Tumoral , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/enzimologia , Feminino , Humanos , Masculino , Metilação , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/sangue , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo
8.
Ann N Y Acad Sci ; 1195 Suppl 1: E52-64, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20586773

RESUMO

Many recent studies have focused on the relationship between biodiversity and ecosystem functioning, such as investigations into the productivity of experimental plant communities. One of the central issues affecting the functioning of ecosystems is the diversity of resident species richness and the composition of the plant community. However, one challenge to experimental studies is that results from artificial ecosystems may have little value for predicting loss of diversity and function degradation in natural ecosystems. Thus, recent studies have focused more on investigations of natural ecosystems; these studies have found that species diversity and ecosystem productivity usually correlate with various abiotic factors including environmental effects, such as soil nutrition and precipitation, as well as anthropic activities, such as grazing and agricultural yield. In this study, we aimed to test the validity of biotic factors reported in experimental studies to be major factors affecting the productivity of ecosystems, and then to determine whether the relationship between biodiversity and ecosystem function is confounded by environmental factors. We investigated the effects of plant biodiversity and community composition on ecosystem function (productivity) in semiarid grassland in Inner Mongolia, China that contained three vegetation types: arid steppe, steppe, and meadow steppe. Our results show that both diversity and community composition significantly affect productivity and are better predictors of productivity than environmental factors, such as soil conditions. Our findings are consistent with the assumptions of niche complementarity. This study suggests that both biodiversity and community composition are important biotic factors in the functioning of ecosystems located in semiarid grasslands. In addition, environmental parameters, such as soil conditions influence productivity indirectly by affecting both biotic factors at the same time.


Assuntos
Biodiversidade , Clima , Monitoramento Ambiental/métodos , Plantas/classificação , Solo , China , Ecossistema , Plantas/genética
9.
Med Hypotheses ; 74(1): 147-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19665313

RESUMO

Although doctors try their best to protect transplants during surgery, there remain great challenges for the higher survival rate and less rejection of transplants after organ transplantation. Growing evidence indicates that the stem cells could function after injury rather than aging, implying that suitable injury may activate the stem cells of damaged organs. Furthermore, it has been revealed that stem cells can be used to induce tolerance in transplantation and the ultrasound has great biological effects on organs. Basing on these facts, we hypothesize that the stem cells within the transplants can be activated by ultrasound with high-frequency and medium-intensity. Therefore, the stem-cell-activated organs (SCAO) can be derived, and the SCAO will be better transplant option for organ transplantation. We postulate the ultrasound can change the molecular activity and/or quantity of the stem cells, the membrane permeability, the cell-cell junctions, and their surrounding microenvironments. As a result, the stem cells are activated, and the SCAO will acquire more regenerative capacity and less rejection. In the paper, we also discuss the process, methods and models for verifying the theory, and the consequences. We believe the theory may provide a practical method for the clinical application of the ultrasound and stem cells in organ transplantation.


Assuntos
Transplante de Órgãos/métodos , Células-Tronco/citologia , Condicionamento Pré-Transplante/métodos , Ultrassom , Comunicação Celular , Sobrevivência de Enxerto , Humanos , Modelos Teóricos , Tolerância ao Transplante , Cicatrização
10.
Med Hypotheses ; 73(6): 1035-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19545954

RESUMO

Hair loss affects many people, especially adult males. An effective treatment is hair transplantation which involves harvesting hair grafts from a donor site and relocating them to a bald site. However, this traditional method, equivalent to one-to-one transplantation, simply redistributes hair rather than increases the number of existing hairs. Although hair transplantation is actually the transplantation of hair follicle (HF), it has been confirmed that whole HFs could be reformed from parts of HFs containing different constituents, implying the existence of more efficient and smaller HF regenerating units in a whole HF. Thus we hypothesize that the most efficient follicular regenerating unit (EFRU) and the smallest follicular regenerating unit (SFRU) could be found in whole HFs. As a result, the one-to-many hair transplantation would be achieved in clinic. One-to-many means to double or triple the number of hairs. In order to test and verify the hypothesis, we design a method called hair follicle micro-dissection (HFM) which aims to help find the regenerating units and increase the number of hair for transplantation. The postulation may provide a more mature and realistic treatment for hair loss if it proved to be practical.


Assuntos
Alopecia/terapia , Cabelo/fisiologia , Regeneração , Humanos
11.
Mol Immunol ; 43(12): 1982-92, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16406095

RESUMO

It was reported recently that histamine induced Toll-like receptor (TLR)2 and TLR4 expression in endothelial cells and enhanced their sensitivity to Gram-positive and Gram-negative bacteria; and that TLRs were expressed in airway epithelial cells and that several inflammatory mediators modulated their expression. However, little is known of potential influence of histamine on TLRs in pulmonary epithelial cells. In the present study, effects of histamine on expression of TLRs in both human A549 and NCI-H292 cell lines were examined by using real-time quantitative RT-PCR analysis, flow cytometry and immunofluorescent staining. The results revealed that both cell types constitutively expressed mRNAs for TLR1-TLR10. Histamine up-regulated the expression of TLR3 mRNA by 12.3- and 11.6-fold, respectively in both cell types. The time course showed that histamine induced TLR3 mRNA expression was initiated at 30 min, nearly reached peak levels after 2 h and was sustained at least until 12 h. Histamine also induced TLR3 protein expression in A549 and NCI-H292 cells. Histamine and poly (I:C), a specific TLR3 ligand stimulated interleukin (IL)-8 secretion from both cell types. Moreover, histamine enhanced poly (I:C)-induced IL-8 secretion and phosphorylation of NF-kappaB in the two cell types, and histamine H1 receptor antagonists inhibited the action of histamine. In conclusion, histamine selectively up-regulated expression of TLR3, and stimulated IL-8 secretion from the cells. Histamine also enhanced poly (I:C) induced IL-8 secretion and phosphorylation of NF-kappaB. These observations suggest that histamine might play an important role in enhancing the innate immune responses of airway to viral infection.


Assuntos
Regulação da Expressão Gênica/imunologia , Histamina/imunologia , Receptor 3 Toll-Like/imunologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Células Epiteliais/imunologia , Histamina/farmacologia , Humanos , Interleucina-8/imunologia , Cinética , NF-kappa B/imunologia , Fosforilação/efeitos dos fármacos , Poli I-C/imunologia , Poli I-C/farmacologia , RNA Mensageiro/análise , Receptor 3 Toll-Like/análise , Receptor 3 Toll-Like/genética
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