Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Adv Mater ; : e2300037, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165538

RESUMO

2D polymers have emerged as one of the most promising classes of organic photocatalysts for solar fuel production due to their tunability, charge-transport properties, and robustness. They are however difficult to process and so there are limited studies into the formation of heterojunction materials incorporating these components. In this work, a novel templating approach is used to combine an imine-based donor polymer and an acceptor polymer formed through Knoevenagel condensation. Heterojunction formation is shown to be highly dependent on the topological match of the donor and acceptor polymers with the most active templated material found to be between three and nine times more active for photocatalysis than its constituent components. Transient absorption spectroscopy reveals that this improvement is due to faster charge separation and more efficient charge extraction in the templated heterojunction. The templated material shows a very high hydrogen evolution rate of >20 mmol h-1 m-2 with an ascorbic acid hole scavenger but also produces hydrogen in the presence of only water and a cobalt-based redox mediator. This suggests the improved charge-separation interface and reduced trapping accessed through this approach could be suitable for Z-scheme formation.

2.
Chem Sci ; 10(45): 10577-10585, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32110343

RESUMO

Effective conversion of solar energy into chemical energy by visible light represents a potential strategy for sustainable development. Among which, photocatalytic hydrogen evolution reaction (HER) with a relatively small activation energy (1.23 eV, around 1000 nm light irradiation) is especially attractive. In this work, well-distributed platinum nanoparticles (Pt-NPs) with a width of about 3 nm have been successfully immobilized into the confined coordination interspaces of 3.7 nm diameter, which are facilitated by early transition metal Hf(iv)-based clusters of a self-sensitized palladium porphyrin metal-organic framework. Under visible light irradiation, the resultant Pt@Pd-PCN-222(Hf) (which is also denoted as Pt@Pd-PMOF-2(Hf)) displays superb photocatalytic activity, achieving an unprecedented maximum H2 evolution rate of 22 674 µmol g-1 h-1 with a turn-over number (TON) of 4131.2 in 32 h and the highest turn-over frequency (TOF) of 482.5 h-1 based on Pt-NPs. This photocatalyst can be recycled and reused for three successive runs without significant loss of catalytic activity. This effective strategy takes advantage of the synergetic effect between Pd-porphyrin photosensitizers and Pt-NP co-catalysts confined within nanoscale coordination interspaces incorporating hydrophilic Hf(iv)-oxo clusters.

3.
Chin J Integr Med ; 21(8): 601-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25533513

RESUMO

OBJECTIVE: To explore susceptibility genes associated with yang-deficiency constitution using single nucleotide polymorphism (SNP) genotyping. METHODS: Based on an epidemiological survey, 30 volunteers with yang-deficiency constitution and 30 volunteers with a balanced constitution were included according to the Classification and Determination Standards of Constitutions in Traditional Chinese Medicine. Peripheral blood was collected and DNA was extracted from white blood cells. A genome-wide association study (GWAS) was conducted by SNP 6.0 genotyping at the Beijing CapitalBio Corporation Ltd. A minimum association P-value (Fisher's exact value) of less than 10(-4) in the allele, genotype, dominant, and recessive models served as the standard for significant association of SNP with yang-deficiency constitution. RESULTS: Among the four genetic models, a total of 42 SNPs were significantly associated with yang-deficiency constitution (Fisher's exact P-values P<10(-4)). These SNPs were adjacent to more than 20 genes, including RGS6, mGluR5, GAPDHL19, and IKZF1. CONCLUSION: Yang-deficiency constitution exhibits the characteristics of polygenic inheritance. This pilot study suggests that the polymorphisms in RGS6, mGluR5, GAPDHL19, and IKZF1 are associated with changes in cyclic adenosine monophosphate and cyclic guanosine monophosphate levels, memory, metabolic energy status, and immune function, respectively in people with yang-deficiency constitution.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Deficiência da Energia Yang/genética , Adolescente , Adulto , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Adulto Jovem
4.
Zhong Xi Yi Jie He Xue Bao ; 10(5): 508-15, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22587972

RESUMO

OBJECTIVE: To explore the analysis methods for composite traditional Chinese medicine (TCM) constitutions. METHODS: The epidemiological data of TCM constitutions were collected from 974 volunteers via a cross-sectional survey. The samples were classified into 9 constitution types according to the maximal standardized scores of imbalanced constitutions. The correlation matrix of 9 constitutions was computed. The standardized scores of 9 constitutions of all the volunteers were ranked respectively, and the composite status of every two constitutions was observed using cross tabulation. The constitution types of all the volunteers were transformed into ternary code of 9 digits, and the composite status of 3 or more than 3 kinds of constitution types was analyzed. RESULTS: According to the maximal standardized scores of imbalanced constitutions, of 974 volunteers, 227, 148, 218, 102, 31, 81, 44, 97 and 26 volunteers had balanced constitution, qi-deficiency constitution, yang-deficiency constitution, yin-deficiency constitution, phlegm-dampness constitution, heat-dampness constitution, blood stasis constitution, qi-stagnation constitution, and inherited special constitution, respectively. The standardized scores of balanced constitution were negatively correlated with those of imbalanced constitutions, while there was a positive correlation between the standardized scores of every two imbalanced constitutions. Among the 8 imbalanced constitutions, one kind of imbalanced constitutions was usually complicated with another kind of imbalanced constitutions. The number of qi-deficiency constitution complicated with yang-deficiency constitution, qi-deficiency constitution complicated with yin-deficiency constitution, and yin-deficiency constitution complicated with yang-deficiency constitution ranked the top three. The constitution types of 974 volunteers were transformed into a total of 465 ternary codes, showing a total of 465 kinds of constitution types; the simplex constitution, the approximately simplex constitution, and the composite constitution of two or more than two types were found in 259, 130, and 585 volunteers, respectively. CONCLUSION: Cross tabulation can show the composite status of every two constitutions, while the ternary code can show the composite status of three or more than three constitutions.


Assuntos
Constituição Corporal , Medicina Tradicional Chinesa , Adolescente , Adulto , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa/métodos , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
5.
Chin J Integr Med ; 16(1): 28-32, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20131033

RESUMO

OBJECTIVE: To explore the relationship between yin-deficiency constitution (YDC) and biochemical indexes by way of observing the endocrinal and immune functions in subjects with YDC. METHODS: On the basis of epidemiological investigation, 60 subjects with YDC and 50 with gentle constitution (GC) were selected according to the pertinent criteria. From each subject, 8 mL of fasting venous blood was drawn at 8:00-9:00 in the morning, with the serum separated by centrifugation 3 000 r/min for 5 min and preserved at -70 degrees Celsius in a freezer. Serum levels of corticosterone, cortisol, adrenocorticotrophic hormone (ACTH), cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), free triiodothyronine (FT3), free thyroxine (FT4), throtropic stimulation hormone, interleukin 1beta (IL-1beta) and interleukin 2 (IL-2) were detected by double-antibody sandwich ELISA; cAMP/cGMP ratio was calculated, and the difference between the two constitutions in terms of these indexes was analyzed. RESULTS: Serum FT3 was 4.16 + or - 1.38 pmol/L in subjects with YDC, which was higher than that in subjects with GC (3.71 + or - 0.55 pmol/L), but levels of cortisol (124.58 + or - 45.36 ng/mL), ACTH (58.92 + or - 14.55 pg/mL), cGMP (66.00 + or - 18.02 pmol/mL) and FT4 (12.33 + or - 3.12 pmol/L) in YDC were lower than those in GC (13.43 + or - 2.31 pmol/L), showing significant difference (P<0.05). CONCLUSION: YDC is related to some extent with the disturbances in the hypothalamus-pituitary-adrenal axis, hypothalamus-pituitary-thyroid axis, cyclic nucleoside system and immune function.


Assuntos
Sistema Endócrino/fisiopatologia , Sistema Imunitário/fisiopatologia , Deficiência da Energia Yin/diagnóstico , Deficiência da Energia Yin/fisiopatologia , Adulto , Biomarcadores/análise , Biomarcadores/sangue , Sistema Endócrino/metabolismo , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Imunitário/metabolismo , Masculino , Medicina Tradicional Chinesa/métodos , Pessoa de Meia-Idade , Nucleosídeos/sangue , Observação , Sistema Hipófise-Suprarrenal/fisiopatologia , Glândula Tireoide/fisiopatologia , Deficiência da Energia Yin/sangue , Deficiência da Energia Yin/imunologia , Adulto Jovem
6.
Zhong Xi Yi Jie He Xue Bao ; 6(12): 1226-32, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19063834

RESUMO

OBJECTIVE: To investigate the changes of endocrine, cyclic nucleotide and immune systems in subjects of yang deficiency constitution, and to explore the relationship among characteristics and causes of yang deficiency constitution, the physiological and biochemical parameters. METHODS: Based on the diagnostic criteria for the clinical epidemiological investigation, sixty subjects of yang deficiency constitution and fifty of normal constitution were selected. Eight milliliters venous blood were taken from overnight fasted subjects at 8:00-9:00. The sera were obtained by centrifugation of the blood at the speed of 3000 r/min for 5 minutes, and they were stored at -70 degrees C until use. The serum levels of corticosterone, cortisol, adrenocorticotrophic hormone (ACTH), cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), free triiodothyronine (FT3), free thyroxine (FT4), thyrotropic-stimulating hormone (TSH), interleukin-1beta and interleukin-2 were measured by enzyme-linked immunosorbent assay; the cAMP/cGMP ratio was also computed; and the differences of the above indexes were compared between the two types of subjects. RESULTS: The serum levels of corticosterone, interleukin-1beta, TSH and cAMP/cGMP ratio of yang deficiency constitution significantly increased as compared with those of normal constitution, and the serum levels of cortisol, ACTH, cGMP and FT4 of yang deficiency constitution significantly decreased in comparison with those of normal constitution. CONCLUSION: Subjects of yang deficiency constitution may be not only related to hypothalamic-pituitary-adrenal axis and hypothalamic-pituitary-thyroid axis, but also related to the functional disorders of cyclic nucleotide and immune systems.


Assuntos
Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Deficiência da Energia Yang/sangue , Deficiência da Energia Yang/imunologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Estudos de Casos e Controles , AMP Cíclico/sangue , GMP Cíclico/sangue , Sistema Endócrino , Feminino , Humanos , Hidrocortisona/sangue , Interleucina-1beta/sangue , Interleucina-2/sangue , Masculino , Pessoa de Meia-Idade , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
7.
Am J Chin Med ; 36(5): 827-34, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19051350

RESUMO

Based on the theory of constitution of Traditional Chinese Medicine (TCM), the human population can be classified into nine constitutions including a balanced constitution and eight unbalanced constitutions (Yang-deficient, Yin-deficient, Qi-deficient, Phlegm-wetness, Wetness-heat, Stagnant blood, Depressed, and Inherited special constitutions). Generally, unbalanced constitutions are more susceptible to certain diseases than balanced constitutions. However, whether such constitution classification has modern genetic and biochemical basis is poorly understood. Here we examined gene expression profiles in peripheral white blood cells from eight individuals with Yang-deficient constitutions and six individuals with balanced constitutions using Affymetrix U133 plus 2.0 expression array. Based on a q < 0.05 and fold-change > or = 2 cutoff, we have identified that 785 genes are up-regulated and 954 genes are down-regulated in Yang-deficient constitution compared to a balanced constitution. Importantly, we found that the expression of thyroid hormone receptor beta (TRbeta) and several key nuclear receptor coactivators including steroid receptor coactivator 1 (SRC1), steroid receptor coactivator 3 (SRC3), cAMP-response element-binding protein (CREB) binding protein (CBP) and Mediator is significantly decreased. Such decreased expression of TR transcription complex may lead to impaired thermogenesis, providing a molecular explanation of the main symptom associated with Yang-deficient constitution, cold intolerance. Future studies are needed to validate these gene expression changes in additional populations and address the underlying mechanisms for differential gene expression.


Assuntos
Perfilação da Expressão Gênica , Medicina Tradicional Chinesa , Sensação Térmica , Deficiência da Energia Yin/genética , Adulto , China , Temperatura Baixa , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Transcrição Gênica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA