Display options:
Normal
Show Abstracts
Compact
Select/unselect all
Displaying article 1-14
p. 1025-1034
Received: 28 February 2008; in revised form: 17 April 2008 / Accepted: 30 April 2008 / Published: 1 May 2008
Show/Hide Abstract
| Download PDF Full-text (488 KB) Abstract: The dissolution of hyaluronan in water leads to its degradation, and as a resultits molecular weight decreases. The degradation of hyaluronan is mainly influenced bytemperature, solution composition, and also its pH. This study describes the influence ofHofmeister series ions on hyaluronan behaviour and hyaluronan film swelling bysolutions of these ions. It was found that Hofmeister ions show lyotropic effectsinfluencing the entanglement of hyaluronan coils and their expansion from solid polymerfilms into swollen gel state. The hydrophobic and hydrophilic interactions in the structureof hyaluronan macromolecules are represented by the mutual diffusion coefficient D(c),the mean mutual diffusion coefficient Ds , the expansion work of coil swelling RAδ,s , theactivation enthalpy of diffusion connected with swelling HD,s and kinematic viscosity ofhyaluronan-ions solutions ν.
p. 1035-1065
Received: 1 February 2008; in revised form: 1 April 2008 / Accepted: 30 April 2007 / Published: 1 May 2008
Show/Hide Abstract
| Download PDF Full-text (225 KB) Abstract: This review describes specific strategies for targeting to the central nervoussystem (CNS). Systemically administered drugs can reach the brain by crossing one of twophysiological barriers resistant to free diffusion of most molecules from blood to CNS: theendothelial blood-brain barrier or the epithelial blood-cerebrospinal fluid barrier. Thesetissues constitute both transport and enzymatic barriers. The most common strategy fordesigning effective prodrugs relies on the increase of parent drug lipophilicity. However,increasing lipophilicity without a concomitant increase in rate and selectivity of prodrugbioconversion in the brain will result in failure. In these regards, consideration of theenzymes present in brain tissue and in the barriers is essential for a successful approach.Nasal administration of lipophilic prodrugs can be a promising alternative non-invasiveroute to improve brain targeting of the parent drugs due to fast absorption and rapid onsetof drug action. The carrier-mediated absorption of drugs and prodrugs across epithelial andendothelial barriers is emerging as another novel trend in biotherapeutics. Several specifictransporters have been identified in boundary tissues between blood and CNScompartments. Some of them are involved in the active supply of nutrients and have been used to explore prodrug approaches with improved brain delivery. The feasibility of CNSuptake of appropriately designed prodrugs via these transporters is described in detail.
(This article belongs to the Special Issue
Prodrugs )
p. 1066-1078
Received: 3 April 2008; in revised form: 24 April 2008 / Accepted: 24 April 2008 / Published: 1 May 2008
Show/Hide Abstract
| Download PDF Full-text (131 KB) Abstract: The 2-picolinium N-ylide 4, generated in situ from the N-acylmethyl-2-picolinium bromide 3, underwent cycloaddition to N-phenylmaleimide or carbon disulfideto give the corresponding cycloadducts 6 and 8, respectively similar reactions ofcompound 3 with some electron-deficient alkenes in the presence of MnO2 yielded theproducts 11 and 12. In addition, reaction of 4 with arylidene cyanothioacetamide andmalononitrile derivatives afforded the thiophene and aniline derivatives 15 and 17,respectively. Heating of picolinium bromide 3 with triethylamine in benzene furnished 2-(2-thienyl)indolizine (18). The structures of the isolated products were confirmed byelemental analysis as well as by 1 H- and 13 C-NMR, IR, and MS data. Both thestereochemistry and the regioselectivity of the studied reactions are discussed. Thebiological activity of the newly synthesized compounds was examined and showedpromising results.
p. 1079-1080
Received: 1 May 2008 / Accepted: 2 May 2008 / Published: 2 May 2008
Show/Hide Abstract
| Download PDF Full-text (21 KB) Abstract: n/a
p. 1081-1110
Received: 26 March 2008; in revised form: 2 May 2008 / Accepted: 7 May 2008 / Published: 7 May 2008
Show/Hide Abstract
| Download PDF Full-text (182 KB) Abstract: Terfenadine (4-[4-(hydroxydiphenylmethyl)-1-piperidyl]-1-(4-tert-butylphenyl)-butan-1-ol) was identified in a biological screening to be a moderate inhibitor (27% inhibition) of the CD81-LEL–HCV-E2 interaction. To increase the observed biologicalactivity, 63 terfenadine derivates were synthesized via microwave assisted nucleophilicsubstitution. The prepared compounds were tested for their inhibitory potency by means ofa fluorescence labeled antibody assay using HUH7.5 cells. Distinct structure-activityrelationships could be derived. Optimization was successful, leading to 3g, identfied as themost potent compound (69 % inhibition). Experiments with viral particles revealed thatthere might be additional HCV infection reducing mechanisms.
p. 1111-1119
Received: 29 April 2008; in revised form: 5 May 2008 / Accepted: 6 May 2008 / Published: 8 May 2008
Show/Hide Abstract
| Download PDF Full-text (145 KB) Abstract: A series of amino acid methyl ester hydrochlorides were prepared in good toexcellent yields by the room temperature reaction of amino acids with methanol in thepresence of trimethylchlorosilane. This method is not only compatible with natural aminoacids, but also with other aromatic and aliphatic amino acids.
p. 1120-1134
Received: 28 April 2008; in revised form: 7 May 2008 / Accepted: 7 May 2008 / Published: 9 May 2008
Show/Hide Abstract
| Download PDF Full-text (87 KB) Abstract: An efficient synthesis of ent-halimanolide 2 (15,16-epoxy-12-oxo-ent-halima- 5(10),13(16),14-trien-18,2β-olide), from ent-halimic acid has been achieved, corroborating the structure of the natural compound and establishing its absolute configuration.
p. 1135-1147
Received: 4 April 2008; in revised form: 17 April 2008 / Accepted: 9 May 2008 / Published: 13 May 2008
Show/Hide Abstract
| Download PDF Full-text (297 KB) Abstract: The difficult cultivation of the saffron plant (Crocus Sativus L.) make the spice of the same name made from its dried stigmas very valuable. It is estimated that some 75,000 blossoms or 225,000 hand-picked stigmas are required to make a single pound of saffron, which explains why it is the world’s most expensive spice. The aim of this study was to identify ways of increasing the fertility and production of saffron. For this purpose, the treatment of saffron bulbs with a synthetic growth hormone – a mixture of Polystimulins A6 and K – and two different microorganism based materials – biohumus or vermicompost and Effective Microorganisms™ (EM) – in four different ways (hormone alone, biohumus alone, EM alone and EM+biohumus) was investigated to determine whether these treatments have any statistically meaningful effects on corms and stigmas. It has been shown that EM + biohumus was the most effective choice for improved saffron cultivation.
p. 1148-1155
Received: 9 April 2008; in revised form: 5 May 2008 / Accepted: 5 May 2008 / Published: 13 May 2008
Show/Hide Abstract
| Download PDF Full-text (207 KB) Abstract: Two new dibenzocyclooctadiene lignans, neglschisandrins C-D (1-2), were isolated from the stems of Schisandra neglecta. Their structures and stereochemistries were elucidated by spectroscopic methods, including 1D- and 2D-NMR and HR-ESI-MS techniques.
p. 1156-1178
Received: 5 February 2008; in revised form: 14 May 2008 / Accepted: 14 May 2008 / Published: 14 May 2008
Show/Hide Abstract
| Download PDF Full-text (423 KB) Abstract: Prodrugs are biologically inactive derivatives of an active drug intended to solve certain problems of the parent drug such as toxicity, instability, minimal solubility and non-targeting capabilities. The majority of drugs for cardiovascular diseases undergo firstpass metabolism, resulting in drug inactivation and generation of toxic metabolites, which makes them appealing targets for prodrug design. Since prodrugs undergo a chemical reaction to form the parent drug once inside the body, this makes them very effective in controlling the release of a variety of compounds to the targeted site. This review will provide the reader with an insight on the latest developments of prodrugs that are available for treating a variety of cardiovascular diseases. In addition, we will focus on several drug delivery methodologies that have merged with the prodrug approach to provide enhanced target specificity and controlled drug release with minimal side effects.
(This article belongs to the Special Issue
Prodrugs )
p. 1179-1188
Received: 3 May 2008; in revised form: 19 May 2008 / Accepted: 19 May 2008 / Published: 20 May 2008
Show/Hide Abstract
| Download PDF Full-text (285 KB) Abstract: A series of symmetrical dimeric proton pump inhibitor (PPI) analogues, designed as novel type DNA minor groove binders, was synthesized and evaluated for anti-tumor activity. Some of these new compounds showed IC50 values below 10 μM in an in vitro anti-tumor test. A molecular modeling study was performed to confirm the sequence selectivity of these compounds towards AT base pairs in DNA. Two effective compounds were selected and docked into the minor groove of DNA. The snug binding may be responsible for their cytotoxic and anti-tumor effects.
p. 1189-1194
Received: 9 May 2008; in revised form: 22 May 2008 / Accepted: 22 May 2008 / Published: 23 May 2008
Show/Hide Abstract
| Download PDF Full-text (85 KB) Abstract: Epidemiological analyses in a large Chinese population have revealed that consumption of vegetables and legumes is inversely associated with the risk of type 2 diabetes (T2D). However, the health benefits of these plants have not been fully explained, which stimulated our interest to identify antidiabetic components from vegetables and legumes through searching medicinal databases, especially those containing traditional Chinese medicines. The results not only provide meaningful clues to understanding the antidiabetic potentials of these plants but also display the possibility of pinpointing food component functions by searching medicinal databases.
p. 1195-1206
Received: 9 April 2008; in revised form: 21 May 1995 / Accepted: 21 May 2008 / Published: 27 May 2008
Show/Hide Abstract
| Download PDF Full-text (80 KB) | Abstract: Lonicera caerulea is a species of bush native to the Kamchatka Peninsula (Russian Far East) whose berries have been extensively studied due to their potential high antioxidant activity. The aim of our work was to investigate the in vivo effects of the antioxidant action of Lonicera caerulea berry extracts on the dynamics of experimentallyinduced tumors. Our data showed that aqueous Lonicera caerulaea extracts reduced the tumor volume when administered continuously during the tumor growth and development stages, but augmented the tumor growth when the administration of extracts started three weeks before tumor grafting. Prolonged administration of Lonicera caerulaea berry extracts induced the antioxidant defense mechanism in the tumor tissues, while surprisingly amplifying the peripheral oxidative stress.
p. 1207-1218
Received: 13 March 2008; in revised form: 19 May 1995 / Accepted: 19 May 2008 / Published: 27 May 2008
Show/Hide Abstract
| Download PDF Full-text (97 KB) Abstract: Polysaccharide extracts were obtained from chestnut bran (Castanea sativa) , grape marc (Vitis vinifera) and apple marc (Malus spp.) and fractionated by size exclusion chromatography after endopolygalacturonase degradation. Compositional and linkage analyses by GC and GC-MS showed the characteristic rhamnogalacturonan structure with specific arabinan (apple marc) and type II arabinogalactan (chestnut bran, grape marc) side chains. Type II arabinogalactan rhamnogalacturonan from chestnut bran significantly stimulated the in vitro differentiation of human keratinocytes, giving evidence of a tight structure-function relationship. This molecule comprises short and ramified 3- and 3,6-β- D-galactan and 5- and 3,5-α-L-arabinan side chains, but also contains significant amounts of t-Xyl and 4-Xyl with a characteristic 2:1 ratio. Enzymatic hydrolysis of this polysaccharide produced fragments of lower molecular weight with unchanged xylose content which conserved the same ability to stimulate human keratinocyte differentiation. It could be then speculated that dimeric xylosyl-xylose and/or longer oligomeric xylose side chains attached to a galacturonan and closely associated to hairy rhamno-galacturonan domains are essential patterns that could determine the biological activity of pectins.
Select/unselect all
Displaying article 1-14
Export citation of selected articles as:
Plain Text
BibTeX
BibTeX (without abstracts)
Endnote
Endnote (without abstracts)
Tab-delimited
PubMed XML
DOAJ XML
AGRIS XML