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1.
Immun Ageing ; 15: 14, 2018.
Article in English | MEDLINE | ID: mdl-29983721

ABSTRACT

BACKGROUND: Abdominal obesity is an independent risk factor for coronary heart disease (CHD) and high serum triglyceride (TG) and free fatty acid levels may precipitate or aggravate CHD. METHODS: We enrolled patients with coronary heart disease in our hospital from October 2008 to July 2009. Patients with high TG and increased WC, i.e. waist phenotype WP were included in group A. In group B, were included patients with high TG but not WP. Group C consisted of patients with WP but not high TG. Finally, Group D was composed of patients without high TG or WP. Serum FFA levels for all patients were measured by ELISA. The relationship between TG levels, WC, FFA levels, and coronary artery score was analysed by a single variable regression. RESULTS: Group A had a significantly higher FFA level than the other groups. Regression analysis showed that FFA, TG, WC, hip circumference, waist-to-height ratio, systolic blood pressure, pulse pressure index, and low-density lipoprotein cholesterol all positively correlated with CAS (r = 0.160 ~ 0.415, P = 0.000 ~ 0.032). After we controlled for traditional risk factors for cardiovascular disease, FFA levels remained positively correlated to the CAS (r = 0.365, P < 0.001). CONCLUSION: The serum FFA level for patients with complications of both increased WC and high TG levels was significantly higher than that of patients without either of these complications. The close correlation between the CAS and FFA levels showed by regression analysis suggested that inflammation in these patients was more serious. Increased WC and high TG levels as well as FFA level are valuable for the prediction of cardiovascular disease and can be applied as a clinical guidance for early intervention in the treatment of coronary heart diseases.

2.
J Am Chem Soc ; 132(23): 8194-201, 2010 Jun 16.
Article in English | MEDLINE | ID: mdl-20469866

ABSTRACT

Microscale four-leaf clover-shaped structures are formed by self-assembly of anionic and cationic porphyrins. Depending on the metal complexed in the porphyrin macrocycle (Zn or Sn), the porphyrin cores are either electron donors or electron acceptors. All four combinations of these two metals in cationic tetra(N-ethanol-4-pyridinium)porphyrin and anionic tetra(sulfonatophenyl)porphyrin result in related cloverlike structures with similar crystalline packing indicated by X-ray diffraction patterns. The clover morphology transforms as the ionic strength and temperature of the self-assembly reaction are increased, but the structures maintain 4-fold symmetry. The ability to alter the electronic and photophysical properties of these solids (e.g., by altering the metals in the porphyrins) and to vary cooperative interactions between the porphyrin subunits raises the possibility of producing binary solids with tunable functionality. For example, we show that the clovers derived from anionic Zn porphyrins (electron donors) and cationic Sn porphyrins (electron acceptors) are photoconductors, but when the metals are reversed in the two porphyrins, the resulting clovers are insulators.


Subject(s)
Porphyrins/chemistry , Electronics , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Optical Phenomena , Spectrophotometry, Ultraviolet , Tin/chemistry , X-Ray Diffraction , Zinc/chemistry
3.
Phys Chem Chem Phys ; 12(16): 4072-7, 2010 Apr 28.
Article in English | MEDLINE | ID: mdl-20379498

ABSTRACT

Porphyrin nanotubes were formed by the ionic self-assembly of tetrakis(4-sulfonatophenyl) porphyrin diacid (H(4)TPPS(4)(2-)) and Sn(IV) tetra(4-pyridyl) porphyrin (Sn(OH(-))(X)TPyP(4+/5+) [X = OH(-) or H(2)O]) at pH 2.0. As reported previously, the tubes are hollow as revealed by transmission electron microscopy, approximately 60 nm in diameter, and can be up to several micrometres long. The absorption spectrum of the porphyrin nanotubes presents monomer-like Soret bands, as well as two additional red-shifted bands characteristic of porphyrin J-aggregates (offset face-to-face stacks). To elucidate the origin of the J-aggregate bands and the internal interactions of the porphyrins, the resonance Raman spectra have been obtained for the porphyrin nanotubes with excitations near resonance with the Soret J-aggregate band and the monomer-like bands. The resonance Raman data reveal that the Sn porphyrins are not electronically coupled to the J-aggregates within the tubes, which are formed exclusively by H(4)TPPS(4)(2-). This suggests that the internal structure of the nanotubes has H(4)TPPS(4)(2-) in aggregates that are similar to the widely studied H(4)TPPS(4)(2-) self-aggregates and that are segregated from the Sn porphyrins. Possible internal structures of the nanotubes and mechanisms for their formation are discussed.

4.
Chem Commun (Camb) ; (47): 7261-77, 2009 Dec 21.
Article in English | MEDLINE | ID: mdl-20024202

ABSTRACT

Porphyrins and related tetrapyrroles have been extensively studied because of their importance in biological processes and they are often used in the development of artificial photosynthesis, catalysis, and sensor systems. Challenges in the development of functional nanoscale porphyrin systems are many, including the need to organize the porphyrins (e.g., to facilitate processes such as energy- and electron transfer) and to couple the porphyrin nanostructures to other nanoscale components (e.g., catalytic elements and conductors) to produce multifunctional nanoscale systems. This article summarizes recent advances in the synthesis of discrete self-assembled porphyrin nanostructures with well-defined shapes and sizes. A novel method for growing metal on the porphyrin nanostructures to produce nanocomposites with metal catalysts or interconnects is also described. Current and potential applications of these nanostructures and porphyrin-metal nanocomposites are discussed.

5.
Nanotechnology ; 19(39): 395604, 2008 Oct 01.
Article in English | MEDLINE | ID: mdl-21832600

ABSTRACT

Monodisperse nanospheres are formed by coordination polymerization tetrakis(4-pyridyl)porphyrin-metal complexes with chloroplatinic acid in aqueous solution. The porphyrin nanospheres and their platinized nanocomposites have potential applications in catalysis and solar energy conversion systems.

7.
J Am Chem Soc ; 126(49): 15954-5, 2004 Dec 15.
Article in English | MEDLINE | ID: mdl-15584716

ABSTRACT

Porphyrin nanotubes are made by ionic self-assembly of two oppositely charged synthetic porphyrin molecules. The diameter of the nanotubes can be altered by modifying the structure of one of the porphyrin tectons. The nanotubes are photocatalytically active, mechanically responsive to light, and are composed of J-aggregates that exhibit resonance light scattering.


Subject(s)
Metalloporphyrins/chemistry , Nanotubes/chemistry , Tin/chemistry , Metalloporphyrins/chemical synthesis
8.
J Am Chem Soc ; 126(51): 16720-1, 2004 Dec 29.
Article in English | MEDLINE | ID: mdl-15612699

ABSTRACT

Porphyrin nanotubes represent a new class of nanostructures for which the molecular building blocks can be altered to control their structural and functional properties. Nanotubes containing tin(IV) porphyrins are photocatalytically active and can reduce metal ions from aqueous solution. The metal is deposited selectively onto tube surfaces, producing novel composite nanostructures that have potential applications as nanodevices. Two examples presented here are nanotubes with a continuous gold wire in the core and a gold ball at the end and nanotubes coated with platinum nanoparticles mainly on their outer surfaces. The latter are capable of photocatalytic reduction of water to hydrogen.

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