Background: Transcription factors hypoxia inducible factor 1alpha (HIF 1alpha) and endothelial PAS domain protein 1 (EPAS1) promote the transcription of vascular endothelial growth factor (VEGF). VEGF enhances angiogenesis and vascular permeability of tumours, which promotes tumour growth and facilitates entry of cancer cells into blood circulation and metastasizing. This study examined whether HIF 1alpha and EPAS1 stimulated angiogenesis through activation of VEGF in human pancreatic carcinoma.
View Article and Find Full Text PDFTo enhance the potency, reduce the side effects and improve oral property of estradiol in estrogen replacement therapy (ERT), 6 novel estradiol-RGD octapeptide conjugates have been prepared. In an ovariectomized mouse osteoporotic model, at an oral dosage of 110.3 nmol/kg per day, their anti-osteoporosis activity was significantly higher than that of estradiol and estradiol-RGD tetrapeptide conjugates, and their risks of thrombogenesis and endometrial hyperplasia were significantly lower than that of estradiol and estradiol-RGD tetrapeptide conjugates.
View Article and Find Full Text PDFTo increase antithrombotic activity, 3S-tetrahydroisoquinoline-3-carboxylic acid (1) was modified with natural amino acids to form 19 novel dipeptide analogs, 3S-tetrahydroisoquinoline-3-carboxyamino acids (5a-s), targeting the intestinal peptide transport system. In vitro assay of 5a-s indicated that their potencies for inhibiting adenosine diphosphate (ADP), arachidonic acid (AA), platelet-activating factor (PAF), and thrombin (TH)-induced platelet aggregations were higher than that of 1. Additionally, in vivo assay of 5a-s indicated that their potencies for inhibiting thrombogenesis in rats were also higher than that of 1.
View Article and Find Full Text PDFTo find selective inhibitor of phosphodiesterase type 5 (PDE5), the essential structure elements of clinically used drugs sildenafil, vardenafil, and tadalafil were combined and a tetracyclic parent was constructed to which in 2-positions substituted acetic acid methylesters were introduced to form 17 novel vasodilators, methyl (11aS)-1,2,3,5,11,11a-hexahydro-3,3-dimethyl-1-oxo-6H-imidazo[3',4':1,2]- pyridin[3,4-b]indol-2-substituted acetates. By molecular field analysis (MFA), an equation of three-dimensional quantitative structure-activity relationship (3D QSAR) was established, which not only revealed the dependence of the in vitro vasorelaxation activities on the structures but also pointed out the way to design new lead compounds properly. Docking these novel vasodilators into the hydrophobic pocket of phosphodiesterase type 5 (PDE5) revealed that their adaptabilities to this pocket did significantly affect on their vasorelaxation activity.
View Article and Find Full Text PDFThe excited-state structural dynamics of nickel(II)tetrakis(2,4,6-trimethylphenyl)porphyrin (NiTMP) and nickel(II)tetrakis(tridec-7-yl)porphyrin (NiSWTP) in a toluene solution were investigated via ultrafast transient optical absorption spectroscopy. An ultrashort stimulated emission between 620 and 670 nm from the S1 state was observed in both nickel porphyrins only when this state was directly generated via Q-band excitation, whereas such a stimulated emission was absent under B (Soret)-band excitation. Because the stimulated emission in the spectral region occurs only from the S1 state, this photoexcitation-wavelength-dependent behavior of Ni(II) porphyrins is attributed to a faster intersystem crossing from the S2 state than the internal conversion S2 --> S1.
View Article and Find Full Text PDFIn Vitro Cell Dev Biol Anim
April 2008
Exposure of fibroblasts to high glucose levels promotes a fibrotic response characterized by increased expression of extracellular matrix components including interstitial collagens. Little is known about the effects of glucose levels on other aspects of fibroblast function. Fibroblasts in the myocardium are surrounded by an extensive extracellular matrix composed predominantly of type I collagen.
View Article and Find Full Text PDFAim: To develop a high-throughput real-time assay based on molecular beacons to monitor the integrase 3'-processing reaction in vitro and apply it to inhibitor screening.
Methods: The recombinant human immunodeficiency virus (HIV)-1 integrase (IN) is incubated with a 38 mer oligonucleotide substrate, a sequence identical to the U5 end of HIV-1 long terminal repeats (LTR). Based on the fluorescence properties of molecular beacons, the substrate is designed to form a stem-loop structure labeled with a fluorophore at the 5' end and a quencher at the 3' end.
A trinuclear metallo-capsule has been assembled from a new tripodal pyridyl ligand and three silver(I) ions; the X-ray structure shows the presence of a Ag-Ag interaction in the solid state giving rise to a non-symmetric capsule arrangement while NMR evidence indicates that the structure in solution is symmetrical.
View Article and Find Full Text PDFObjective: To evaluate the significance of the expression of matrix metalloproteinases (MMPs) in prostate cancer (PCa) and its clinical association.
Methods: Fifty one cases of PCa and 10 cases of BPH were studied by immunohistochemical method using monoclonal antibodies to MMP2 and MMP9.
Results: There was significant correlation between MMP2 or MMP9 and pathological grade, Gleason score and PCa metastasis.
Discrete cobalt(II) and nickel(II) complexes of type ML (where L is a bis(2,4-pentanedionate) derivative incorporating a -SCH2CH2S- bridge between the gamma-carbons of respective beta-diketone units) have been synthesised and represent the first examples in which a gamma-substituted, thioether-containing beta-diketone ligand coordinates via a sulfur and oxygen donor in preference to the classical coordination mode involving both beta-diketonate oxygens.
View Article and Find Full Text PDFZhong Xi Yi Jie He Xue Bao
July 2004
Objective: To observe the therapeutic effect of Chinese herbal recipe Zhifang I Decoction on nonalcoholic fatty liver disease (NAFLD) complicating hyperuricemia (HUA).
Methods: Forty-six patients suffering from NAFLD complicating HUA were randomly divided into treatment group (25 cases) with Zhifang I and control group (21 cases) with Xuezhikang Capsule. One course of treatment was 8 weeks.
Aim: To understand pharmacophore properties of styrylquinoline derivatives and to design inhibitors of HIV-1 integrase.
Methods: Comparative molecular field analysis (CoMFA) was performed to analyze three-dimensional quantitative structure-activity relationship (3D-QSAR) of styrylquinoline derivatives. Thirty-eight compounds were randomly divided into a training set of 28 compounds and a test set of 10 compounds.