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The deposition of polyaniline (PANI) onto the surface of plasticized poly(vinyl chloride) (PVC) membranes requires optimizing the membrane composition. Controlling the ratio between the plasticizer and PVC enables the hydrophilic surface to be prepared and a homogeneous PANI film to be deposited through chemical polymerization. Our studies showed that such modified PVC membranes can be used for the potentiometric detection of three tumor markers (TMs) that are metabolites of catecholamines and serves as a screening test for neuroblastoma. Furthermore, the interactions of PANI with these TMs were proved by a capillary electrophoresis method in which a capillary covered with PANI was used.

Ultra‐fine grain sizes have been shown to enhance some key mechanical and functional properties of engineering materials, including shape memory alloys. While the effect of ultra‐fine and nanocrystalline grain sizes on pseudoelastic shape memory materials is well‐appreciated in medical device engineering, the effect of such microstructures on actuators has not been sufficiently characterized. In the present work, it is demonstrated that NiTi spring actuators with ultra‐fine grained microstructures can be obtained by conventional wire drawing in combination with heat treatments and that the final grain size can be controlled by varying the final annealing temperature. Annealing at 400 °C for 600 s allows for the evolution of microstructures with median grain sizes of about 34 nm, while annealing at 600 °C for the same length of time results in median grain sizes of about 5 µm. It is observed that the grain size strongly affects the elementary processes of the martensitic phase transformation. Small austenite grain sizes inhibit twinning accommodation of transformation strains, such that a higher driving force is required to nucleate martensite. This increase in the martensite nucleation barrier decreases the martensite transformation temperatures such that only partial transformation to martensite is possible upon cooling to room temperature. The incomplete martensitic transformation reduces the exploitable actuator stroke; however, a reduction in grain size is shown to improve the functional stability of the material during thermal and thermomechanical cycling by reducing the irreversible effects of dislocation plasticity.

Hopanoids, widespread compounds of triterpene nature, are found mainly in different bacterial types (G and G- bacteria, aerobs, facultative anaerobs, strict anaerobs), in methanotrophs, acetic acid bacteria, nitrogen fixers, purple non-sulphur bacteria, cyanobacteria, and also in sediments. They occur in a variety of structures from simple hopanoids to elongated compounds with polyfunctional side chains such as bacteriohopanepolyols (BH-polyols). This review summarizes current knowledge of the occurrence of these compounds in different bacterial types, genera and species, their biosynthesis and functions in cellular membranes and in important biochemical and physiological processes, and surveys advances and trends in the field of hopanoid analysis, especially as concerns LC-MS with soft ionization techniques such as APCI and/or ESI.

Terpenoid compounds of natural origin with antiviral activities, namely triterpenes and steroids, include compounds with potential future medical use as well as substances in different stages of clinical research and testing. These natural compounds have often been synthetically modified, the modification including both changes in the basic structure or mere substituent modifications.

Terpenoids, biosynthetically related ubiquitous compounds found in virtually all living organisms from marine invertebrates to blooming plants, are derived from the same precursor but their structures and biological and/or pharmacological activities are widely different. Our review concerns terpenoid compounds with antiviral activities, from the simplest sesquiterpenes to diterpenes and sesterterpenes. They include commercially produced therapeutics, compounds with documented antiviral effects and potential future medical use, as well as substances in different stages of clinical research and testing. All of them are based on natural compounds, with only partial man-made changes in the basic structure or mere substituent modifications.

The heat labile carotenoids cannot be analyzed by gas chromatography (GC) and GC-mass spectrometry (GC- MS). The only useful method appears to be high-performance liquid chromatography (HPLC) with UV/visible (UV/Vis) or mass spectrometric detection (LC-MS). Reversed-phase HPLC (RP-HPLC) is a preferred method, which is frequently used with C18 stationary phase, usually with gradient elution. In contrast to other ionization techniques, xanthophylls and carotenes form both molecular ions and protonated molecules during positive ion APCI (atmospheric pressure chemical ionization). APCI is an ideal method of ionization for low- to medium-polar compounds, which include also carotenoids and related compounds. Since their molecular mass does not exceed 2000 amu even in the case of glycosides or esters with fatty acids, this method is exceedingly suitable for their analysis. The review summarizes the data on its use for this group of compounds.

Triacylglycerols (TAGs) are widely distributed, if not universal, in edible plants and edible plant triacylglycerols are nutrients forming an important part of the human diet. TAGs of higher plants consist mainly of esters of glycerol with fatty acids, many of which are essential as human nutrients and are therefore in the center of increasing attention. Despite their importance, the molecular species of each TAG class have not yet been fully characterized. The use of state-ofthe- art techniques, especially in a combination such as that discussed in this review, permits the identification of not only TAG classes, but also their positional isomers and often also individual molecular species. Atmospheric pressure chemical ionization mass spectrometry (APCI-MS) in combination with high-performance liquid chromatography (HPLC) has proven to be a very valuable technique for analysis of different lipids from a variety of sources. This paper describes direct analyses of TAGs from natural oils, frequently very unusual, using LC-MS/APCI.

Hirtusneanoside, a new O-deoxyglycoside of a dimeric tetrahydroxanthone, was isolated from the lichen Usnea hirta. Its structure, including the absolute configuration, was determined by means of extensive spectroscopic data (UV, IR, MS, CD, 1D and 2D NMR) and chemical degradation. Hirtusneanoside has a unique structure comprising l-rhamnopyranoside of a tetrahydroxanthone dimer and showed growth inhibitory activities against Gram-positive bacteria.

Resistance to transforming growth factor (TGF)–β1–mediated growth suppression in tumor cells is often associated with the functional loss of TGF-β receptors. Here we describe two B-cell lymphoma cell lines (DB and RL) that differ in their sensitivity to TGF-β1–mediated growth suppression. The TGF-β1–resistant cell line DB lacked functional TGF-β receptor II (TβRII) in contrast to the TGF-β–responsive cell line RL, whereas both cell lines had comparable levels of receptor I (TβRI). Lack of functional TβRII was correlated with the lack of TGF-β1–induced nuclear translocation of phospho-Smad3 and phospho-Smad2, the lack of nuclear expression of p21Cip1/WAF1, and the down-regulation of c-Myc in DB cells. Transfection of wild-type, but not a C-terminal–truncated, form of TβRII rendered the DB cell line responsive to TGF-β1–mediated growth suppression. Analysis of the TβRIIgene in DB cells revealed the absence of TβRII message, which was reversed upon 5′-azacytidine treatment, indicating that the promoter methylation might be the cause of gene silencing. Promoter analysis revealed CpG methylations at −25 and −140 that correlated with the gene silencing. These data suggest that promoter methylation plays an important role in TβRIIgene silencing and subsequent development of a TGF-β1–resistant phenotype by some B-cell lymphoma cells.

Lincomycin and its derivatives are antibiotics exhibiting biological activity against bacteria, especially Grampositive ones, and also protozoans. Lincomycin and its semi-synthetic chlorinated derivative clindamycin are widely used in clinical practice. Both antibiotics are bacteriostatic, inhibiting protein synthesis in sensitive bacteria, and they may even be bactericidal at higher concentrations that can still be reached in vivo. Clindamycin is usually more active than lincomycin in the treatment of bacterial infections, in particular those caused by anaerobic species; it can also be used for the treatment of important protozoal diseases, e.g. malaria, most effectively in combination with other antibiotic or nonantibiotic antimicrobials (primaquine, fosfidomycin, benzoyl peroxide). Resistance to lincomycin and clindamycin may be caused by methylation of 23S ribosomal RNA, modification of the antibiotics by specific enzymes or active efflux from the bacterial cell. In addition to the various medicinal applications and modes of microbial resistance to lincosamides, the review describes the chemical structures of lincosamide antibiotics and analytical procedures used for identification, separation and isolation of these compounds and their metabolites. The biosynthesis of lincomycin and related compounds and its genetic control are also briefly discussed.

In addition to sulfur-containing compounds that form essential and indispensable constituents of all living cells, there is a plethora of less wide-spread sulfur-containing compounds with much less common and often unexpected properties, chemical structures and biological activities. Some of these compounds have long been known as efficient antibiotics. This review surveys these less known compounds with two and more sulfur atoms in their molecule. In particular, it deals with natural heterocyclic compounds isolated, e.g., from bacteria, fungi, lichens, plants, and animals but also from unusual and exotic sources such as sea invertebrates (coelenterates, sponges, tunicates, sea worms), etc. Compounds such as calicheamicins, thiazole-related compounds and epipolythiodioxopiperazines may serve as examples. Because of their vast variety, individual compounds are grouped according to their chemical structure (only compounds whose chemical structure has been identified are included). These compounds affect a huge array of organisms from microorganisms to man, and the pharmacological activities they exert range from antiviral, antibacterial, antifungal, insecticidal or antiprotozoan effects to regulation of gene expression, cytoskeleton disruption, immunomodulation, plant growth stimulation or inhibition, pro- or antioxidant action, effects on selected enzymes, receptors and signal transduction pathways, etc. The activities are however often known only sketchily, and this paucity of data, and the fact that the activities were tested on a diverse spectrum of test organisms, cell lines, etc., is of necessity reflected in our survey. Two seemingly trivial but important points deserve attention: (a) compounds with widely different structures and from widely different sources have often very similar pharmacological effects; (b) a slight modification in the molecule may bring vast changes in the biological effects of the compound, in terms of quality, quantity and targeting. The purpose of the review was to show both the unique and common features of these compounds and to point out their potential usefulness for mankind.

Primary adult-type hypolactasia is a hereditary metabolic condition which leads to clinical manifestation usually during early adulthood and is frequently associated with clinical symptoms of lactose intolerance. The prevalence of adult-type hypolactasia varies extremely in different populations; in Central Europe, it is about 15–40%. The CC homozygous genotype of the LCT (T/C-13910) polymorphism on chromosome 2q21 is strongly associated with primary adult-type hypolactasia. For rapid genotyping by real-time PCR we developed a genetic test using fluorescently labeled hybridization probes. We genotyped 60 patients with clinically suspected lactose intolerance and compared the results of the new genetic test with clinical data and lactose H2 breath test results, the clinically most widely used non-invasive test for the diagnosis of lactose malabsorption. 80% of the CC individuals were lactose malabsorbers, whereas only 30% of the TC or TT individuals were classified as lactose malabsorbers according to their H2 breath test results. The genetic test ist suitable for routine clinical applications and of great value for the reliable differentiation between lactose malabsorbers with adult-type hypolactasia and patients with secondary hypolactasia due to different gastrointestinal disorders or small intestinal bacterial overgrowth.

Very-long-chain and multibranched polyunsaturated fatty acids of three freshwater sponges, Ephydatia syriaca, Nudospongilla sp., and Cortispongilla barroisi, were studied by silver TLC, GC−MS, UV, IR, HRMS, and NMR methods. One hundred and eighty-five conventional fatty acids were identified by GC−MS, out of which five were new multibranched polyunsaturated fatty acids. The freshwater sponges belonging to the family Spongillidae (class Demospongia) were shown to contain novel di-, tri-, and tetramethyl substituted dienoic, tetraenoic, and hexaenoic fatty acids. The compounds gave positive results in a brine shrimp toxicity assay.

The majority of anti-phosphocholine (PC) antibodies induced by the PC epitope in Proteus morganii (PM) express the M603 idiotype (id), which is characterized by an invariant Asp to Asn substitution at the VH:DH junction. To elucidate the molecular basis by which M603-like B cells acquire the mutations resulting in this invariant substitution, we analyzed the immune response to PC-PM in terminal deoxynucleotidyl transferase (TdT) gene knockout (KO) mice. In the absence of TdT, T15-id antibodies comprised 80–100% of the primary response to PC-PM. Less than 10% of the response in wild-type mice is T15-id⁺. In TdT KO mice, the secondary response to PC-KLH was higher than in wild-type mice and was dominated by the germ-line T15-id. About 10% of this response, in both TdT KO and wild-type mice, comprised M167-id⁺ antibodies. Additionally, none of the functionally rearranged V1/DFL16.1/JH1 cDNA isolated from PC-PM-immunizedTdT KO mice showed the Asp/Asn substitution characteristic of PC-binding, PC-PM-induced M603-like antibodies. These data indicate that production of M603-id antibody is TdT dependent, while generation of M167-id antibody is TdT independent, and that in the absence of competition from M603-like B cells, T15-id B cells can respond to PC-PM.

The fatty acid composition of the willow leaf beetle Chrysomela vigintipunctata (Scopoli) (Coleoptera: Chrysomelidae) is presented in this paper. Fatty acids in the total lipid extract, triacylglycerols, free fatty acids and polar lipids were compared. One hundred and fifteen fatty acids were identified in the total lipids. The mixture comprised compounds with normal and branched-chains of 12-30 carbon atoms and zero to six double bonds in different positions in the carbon chain. Substantial amounts of unsaturated eicosanoic fatty acids known as important precursor of eicosanoids in insects were detected in the lipids as were biologically significant positionally isomeric dienes, trienes and tetraenes of the series (n-3) and (n-6) of C16, C18, and C22 fatty acids. Also present was a mixture of hydroxy-FA. Triacylglycerols contained mostly saturated and monounsaturated fatty acids. Polyunsaturated fatty acids were found mostly in free fatty acids and especially in polar lipids.

The isomer213mRa was produced by the reaction209Bi(10B, 6n), as well as by bombardments of12C on Pb isotopes,14N on Bi, and16O on natural Hg, with projectile energies in the range 60–100 MeV. The isomer decays with a halflife of 2.1 ms both via gamma internal transitions and via alpha branching to levels in209Rn. A level scheme is proposed in which the isomeric state is assigned as either 17/2- or 13/2+ with shell-model configurations either of theh9/2 protons coupled to ap1/2 neutron hole, or of an uncoupledi13/2 neutron hole. On the basis of alpha decay rate predictions from the new Fliessbach theory, the 17/2- isomeric assignment is to be preferred.