Normal <Emphasis Type="Italic">π</Emphasis>-complements for finite groups

Let G be a finite group. For a finite p-group P the subgroup generated by all elements of order p is denoted by Ω₁(p). Zhang [5] proved that if P is a Sylow p-subgroup of G, Ω₁(P) ≦ Z(P) and N _G (Z(P)) has a normal p-complement, then G has a normal p-complement. The object of this paper is to generalize this result. This paper was partly supported by Hungarian National Foundation for Scientific Research Grant # T049841 and T038059.     

Spectroscopic and thermal studies of chromium(III), molybdenum(VI) and ruthenium(0) complexes of maleic hydrazide

Interaction of maleic hydrazide (LH(2)) with [Cr(CO)(6)] in air at atmospheric pressure resulted in the formation of the complex [(LH)Cr(mu-O)(2)Cr(LH)] (1). Reaction of LH(2) with [Mo(CO)(6)] in air also gave the complex [(LH(2))O(2)Mo(mu-O)(2)MoO(2)(LH(2))] (2). Under the same conditions, the reaction of LH(2) with [Ru(3)(CO)(12)] resulted in the formation of the tricarbonyl complex [Ru(CO)(3)(LH(2))] (3). The complexes were characterized by elemental analysis, IR, and (1)H NMR spectroscopy. The thermal properties of the complexes were investigated by thermogravimetry technique.     

Determination of chamazulene carboxylic acid in serum by high-performance liquid chromatography. Development and validation

A new, simple and sensitive high-performance liquid chromatographic (HPLC) method was developed for the determination of chamazulene carboxylic acid (CCA) in serum. The technique is based on a single liquid-liquid extraction of the substance using ibuprofen as internal standard (I.S.). The separation was achieved on a C(18) reversed-phase column using acetonitrile/water (4:6, pH 3) as mobile phase. The effluent was monitored at 221 and 286 nm. The calibration curves were linear over the concentration range of 0.1-30 microg/ml. The intra- and inter-day RSDs were in all cases less than 15 and 11%, respectively. The limit of quantitation was 0.1 microg/ml. The assay was developed and validated to be applied in a pharmacokinetic study in healthy volunteers.     

Quintic nonpolynomial spline solutions for fourth order two-point boundary value problem

In this paper, we develop quintic nonpolynomial spline methods for the numerical solution of fourth order two-point boundary value problems. Using this spline function a few consistency relations are derived for computing approximations to the solution of the problem. The present approach gives better approximations and generalizes all the existing polynomial spline methods up to order four. This approach has less computational cost. Convergence analysis of these methods is discussed. Two numerical examples are included to illustrate the practical usefulness of our methods.     

On the explicit solutions of forms of the Sylvester and the Yakubovich matrix equations

In this paper, we consider the explicit solutions of two matrix equations, namely, the Yakubovich matrix equation V−AVF=BW and Sylvester matrix equations AV−EVF=BW,AV+BW=EVF and AV−VF=BW. For this purpose, we make use of Kronecker map and Sylvester sum as well as the concept of coefficients of characteristic polynomial of the matrix A. Some lemmas and theorems are stated and proved where explicit and parametric solutions are obtained. The proposed methods are illustrated by numerical examples. The results obtained show that the methods are very neat and efficient.     

Identification and molecular modeling of new quinolin-2-one thiosemicarbazide scaffold with antimicrobial urease inhibitory activity

Molecular Diversity - A new series of 6-substituted quinolin-2-one thiosemicarbazides 6a–j has been synthesized. The structure of the target compounds was proved by different spectroscopic...     

Stereoselective Synthesis of Sialyl Lewisa Antigen and the Effective Anticancer Activity of Its Bacteriophage Qβ Conjugate as an Anticancer Vaccine

Sialyl Lewis^a (sLe^a), also known as cancer antigen 19-9 (CA19-9), is a tumor-associated carbohydrate antigen. The overexpression of sLe^a on the surface of a variety of cancer cells makes it an attractive target for anticancer immunotherapy. However, sLe^a-based anticancer vaccines have been under-explored. To develop a new vaccine, efficient stereoselective synthesis of sLe^a with an amine-bearing linker was achieved, which was subsequently conjugated with a powerful carrier bacteriophage, Qβ. Mouse immunization with the Qβ-sLe^a conjugate generated strong and long-lasting anti-sLe^a IgG antibody responses, which were superior to those induced by the corresponding conjugate of sLe^a with the benchmark carrier keyhole limpet hemocyanin. Antibodies elicited by Qβ-sLe^a were highly selective toward the sLe^a structure, could bind strongly with sLe^a-expressing cancer cells and human pancreatic cancer tissues, and kill tumor cells through complement-mediated cytotoxicity. Furthermore, vaccination with Qβ-sLe^a significantly reduced tumor development in a metastatic cancer model in mice, demonstrating tumor protection for the first time by a sLe^a-based vaccine, thus highlighting the significant potential of sLe^a as a promising cancer antigen.     

Synthesis of a Systematic 64-Membered Heparan Sulfate Tetrasaccharide Library

Heparan sulfate (HS) has multifaceted biological activities. To date, no libraries of HS oligosaccharides bearing systematically varied sulfation structures are available owing to the challenges in synthesizing a large number of HS oligosaccharides. To overcome the obstacles and expedite the synthesis, a divergent approach was designed, where 64 HS tetrasaccharides covering all possible structures of 2-O-, 6-O- and N-sulfation with the glucosamine-glucuronic acid-glucosamine-iduronic acid backbone were successfully produced from a single strategically protected tetrasaccharide intermediate. This extensive library helped identify the structural requirements for HS sequences to have strong fibroblast growth factor-2 binding but a weak affinity for platelet factor-4. Such a strategy to separate out these two interactions could lead to new HS-based potential therapeutics without the dangerous adverse effect of heparin-induced thrombocytopenia.