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Five types of scintillators for parallel detection of neutrons and γ were tested for their pulse shape discrimination ability. All detectors are based on

Srdecni selhani je provazeno městnanim v jatrech, akutni dekompenzace může vest k progresi stavu. Odrazem těchto změn může být porucha jaternich funkci, ktera se projevi vzestupem transaminaz. Cilem studie je posouzeni prognostickeho významu zvýsených hodnot parametrů jaternich funkci u nemocných s akutnim srdecnim selhanim. V souboru 92 pacientů (66,2 ± 13,9 let) byl analyzovan vztah mezi vstupni hodnotou bilirubinu, aspartataminotransferazy (AST), alaninaminotransferazy (ALT), gama-glutamyltransferazy (GGT), alkalicke fosfatazy (ALP) a mortalitou. Studie ukazala signifikantni zvýseni hladin transaminaz u zemřelých: AST (median (IQR): 1,15 (0,65–3,28) vs. 0,49 (0,41–0,90), p 0,01) a ALP (2,0 (1,78–2,66) vs. 1,75 (1,13–2,12), p 0,01). AST se ukazala být take významným rizikovým faktorem urcujici 30denni a jednorocni mortalitu (30denni mortalita: HR = 3,9, 95 % CI: 1,19–12,76, p 0,02, jednorocni mortalita: HR = 3,31, 95 % CI: 1,35–8,1, p 0,008). Výsledky studie potvrzuji zvýseni hladiny transaminaz u nemocných se srdecnim selhanim a ukazuji asociaci hladin transaminaz s mortalitnimi ukazateli.

The majority of people like catastrophic stories, especially if they are far enough. The asteroid hazard has become one of classical thriller and/or sci-fi subjects. In fact Earth collision with asteroid has a very low probalility, but it is not a sci-fi. So educating public and media on detection, impact effects, mitigation missions, impact warnings belong to the most important tasks of NEOs scientists and research institutions. Recent research results in the field of Near-Earth Objects (NEO) cause growing interest among general public too. Furthermore NEO related issues have outstanding educational value and outreach potential. It could be a responsibility of NEO scientists to spread clear, correct, concise, comprehensive and up-to-date information to wide public, students, educators, media as well as to decision makers.

The Near-Earth Objects (NEOs) are the most important of the small bodies of the solar system, having the capability of close approaches to the Earth and the chance to collide with the Earth. We present here the current system of discovery of these dangerous objects, standards for selecting useful and important targets for NEO follow-up astrometry, system of impact probabilities calculations, and also determination of impact site and evacuation area.

Objectives: Interleukin 6 plays an important role in chronic heart failure (HF), but little is known about its involvement in acute decompensated heart failure (ADHF). The aim of our study is to evaluate the prognostic role of interleukin 6 (IL-6) in the patients with ADHF.Methods: Plasma levels of interleukin IL-6, N-terminal pro brain natriuretic peptide levels, and clinical covariates were measured in 92 patients with ADHF. Survival was followed up to 12 months, and prognostic factors were evaluated.Results: Elevated plasma IL-6 levels were increased in nonsurvivors and were associated with 1-year mortality (pConclusions: Plasma IL-6 levels provide important prognostic information in the patients with ADHF. Measurement combining plasma IL-6 and NT-proBNP should serve as a powerful prognostic tool of multimarker strategy in patients with acute decompensated heart failure.

By means of selective deuterium labeling of 1-aza[6]helicene combined with resolution of the enantiomers, chiral discrimination in silver(I)-bound dimers of the type [LAgL′]+ is probed by electrospray mass spectrometry. The analysis of the results reveals a pronounced preference for the formation of homochiral dimers (P,P and M,M, respectively) over the statistically preferred heterochiral variant (P,M), which is fully consistent with previous data about the formation of homochiral dimers in the condensed phase. Further, competitive experiments with mixtures of 1- and 2-aza[6]helicene suggest a largely preferred coordination of 1-aza[6]helicene to the silver(I) cation.

Immunoglobulin D (IgD) multiple myeloma (MM) is a rare plasma cell disorder constituting less than 2% of all MM cases. Survival of patients with IgD MM is generally shorter than that of patients with other types of monoclonal (M-) protein. We have retrospectively analyzed patients with IgD MM participating in clinical trials of the Czech Myeloma Group. Twenty-six IgD MM patients treated between 1996 and 2006 were identified, 14 (54%) men and 12 (46%) women. The median age was 61 years (range: 37–79 years). Ten of 26 patients (39%) were treated with first-line high-dose chemotherapy (HDCT) using melphalan 200 mg/m2 followed by autologous stem cell transplantation (ASCT). Thirteen of 26 patients (50%) received conventional chemotherapy (CHT), mostly melphalan and prednisone or a vincristine/doxorubicin/dexamethasone (VAD) regimen. Treatment responses were evaluable for 23 of 26 (89%) patients. All HDCT patients had treatment responses, including seven patients (70%) with complete responses and three patients (30%) with partial responses. The median progression-free survival was 18 months for HDCT patients and 20 months for CHT patients. The median overall survival (OS) for all patients was 34 months. The median OS for the HDCT group has not yet been reached (70% of the patients are still alive). In contrast, the median OS for CHT patients was only 16 months. The difference in OS between the two groups was statistically significant (P=0.005). In conclusion, the overall response rate for patients with IgD MM aged 65 years or less treated with HDCT and ASCT is similar to that seen in other MM types.

Aim. The aim of this study was to analyse the relation between clinical, haemodynamic and X-ray parameters and plasma NT-proBNP level in pts with symptoms of left ventricular dysfunction. Methods. The plasma NT-proBNP levels, chest x-ray, transthoracic 2-d and Doppler echocardiography were performed at the time of admission in a group of 96 consecutive patients (mean age 68 ± 11 years) with symptoms of acute heart failure. NT-proBNP levels were assessed with the use of commercial tests (Roche Diagnostics). Results. All patients have significant increase in NT-proBNP (8 000 ± 9 000 pg/mL vs. controls 90 ± 80 pg/mL, p < 0.001). The group of all patients has shown a significant increase in cardiothoracic ratio (CTR, 0.6 ± 0.1, vs. 0.4 ± 0.1, p

In the recent times, there has been a noticeable increase in interest about NEOs. In the light of results of recent NEO surveys the need for continuous follow-up astrometry to secure the orbits of the discovered bodies has risen.The Klet' Observatory Near Earth and other Unusual Objects Observation Team and Telescope, project KLENOT, started in 2002. It is dedicated to confirmation, follow-up, and recovery of NEOs. For this task the 1.06-m KLENOT telescope, equipped with a high-efficiency CCD is used. Since it was set in service in March 2002, a significant number of results have been obtained. For instance, 10,000 positions have been determined, more than 400 confirmations made, including 16 recoveries and 104 Virtual Impactors measured.An important part of NEO search is the discovery of comets. Therefore an inseparable component of NEO follow-up includes the detection of possible cometary features of newly discovered bodies and the confirmation of Near Earth Comets (NEC).In the next decade, surveys will be characterized by several aspects. Pan-STARRS opens the question whether “classical” confirmation and early follow-up of newly discovered NEO candidates will be necessary by others, and we discuss the need for possible changes in existing system of follow-up process. The most important challenge for follow-up will likely become the NEOs which are in urgent need of astrometric positions over longer arcs including Virtual Impactors, radar, and mission targets. The observing strategies and obtained results of the KLENOT Project will be presented as well as future plans will be discussed.One of the most important duties of NEOs scientists and research institutions is to maintain contact with the public. NEO related issues have outstanding educational value and outreach potential. Nowadays the Internet has proved itself to be an excellent mean of bringing NEO knowledge to a wider audience.

The title tetrasubstituted spirobifluorenes 3a, 3b have been designed to serve as convenient achiral tectons for self-assembly of 2D layers with large chiral pores. The underlying stereochemical concept has been confirmed by the results of crystallographic analysis of tetraacid 3a. Self-assembly of isosteric tetraamide 3b led to markedly different results.

Crystallographic analysis of the title binaphthyl tetracid 2 revealed unique propensity to polycatenation upon crystallization of both the enantiomerically homogeneous as well as the racemic form of the axially chiral tecton. Stereochemical aspects of the polycatenation have been analyzed in three conceptual steps, (i) formation of infinite 2D grids set up from hydrogen-bonded tecton cyclotetramers, (ii) stacking of the 2D grids, and (iii) interpenetration of the resulting stacks. In the crystal self-assembly of the enantiomerically uniform tecton, all three steps are homochiral. Conversely, in the crystal of the racemic tecton the homochiral self-assembling algorithm operates only in the steps (i) and (ii), giving rise to separate, antipodal, stacks of homochiral 2D layers. In the final step (iii), the antipodal stacks mutually interpenetrate, yielding racemic 3D polycatenated architecture within a single crystal.

X-ray diffraction analysis revealed unexpected stereochemical features accompanying crystal self-assembly of the two title oligocarboxylic acids.

Long-term effects of low doses of highly toxic organophosphorus agent sarin on various hematological and biochemical markers and physiological functions were studied in rats exposed to sarin by inhalation. The results indicate that low-level sarin-exposed rats show long-term increase in studied markers of stress and decrease in synthesis of DNA de novo without the disturbance of the functions of cholinergic nervous system. Moreover, sarin at low doses is able to induce some neurotoxic effects including an increase in the excitability of central nervous system in rats at 3 mo following inhalation exposure. Relatively long-term spatial discrimination impairments in rats exposed to low-level sarin was demonstrated too. Therefore, nerve agents such as sarin seem to be harmful not only at high, clinically symptomatic doses but also at low doses without acute clinical manifestation of overstimulation of cholinergic nervous system because of long-term manifestation of alteration of neurophysiological and neurobehavioral functions in sarin-exposed rats.

Distant comets C/2002 A1 and C/2002 A2 make up a peculiar pair that moves about the Sun in virtually identical, somewhat unstable orbits, extending currently between about 4.7 and 29 AU from the Sun. The two objects, observed since late 2001, are unquestionably of common origin. Analysis of their relative motion indicates that their parent body split nontidally most probably between mid-1977 and early 1979 at a heliocentric distance of 22.5 ± 0.1 AU and about 2.5 AU below the ecliptic, with a separation velocity of 2.7 ± 0.2 m s-1. The motion of C/2002 A2, the secondary component that trails behind the primary, is found to be affected by a nongravitational deceleration of (13.4 ± 1.5) × 10-5 units of solar gravitational acceleration relative to C/2002 A1, which is in a range of decelerations that companions of split comets are usually subjected to. C/2002 A2 was somewhat less condensed and, interestingly, brighter than C/2002 A1.

2,2′,5,5′-Tetracarboxy- and 2,2′,5,5′-tetracarbamoyl-substituted biphenyls and also the 2,2′,3,3′,6,6′-hexacarboxy-substituted analogue behave as Siamese twins of terephthalic tectons in the single crystal self-assembly, giving rise to chiral 2D grid layers. A comparison has been made with the corresponding 2,2′,6,6′-tetrasubstituted biphenyls which mimic isophthalic twins in their self-assembly.

Self-assembly of 4,4'-bipyridine-2,2',6,6'-tetracarboxamide and its 1 : 1 silver(I) triflate complex was investigated by single crystal X-ray diffraction analysis. It was found that intermolecular amide-amide hydrogen bonds control the crystal packing of the free base giving rise to infinite zig-zag tapes, whereas an octahedral coordination of the Ag(I) ion with the ligand dominates in the packing of the corresponding complex.

Single-crystal X-ray diffraction revealed that the molecules of both the title compounds (S)-5 and (S)-6 are linked, via double hydrogen bonds, in infinite chains which follow the crystallographic symmetry of the three- and four-fold screw axis, respectively. To our knowledge this represents the first documented case when intermolecular carboxylic hydrogen bond constitutes an integral part of a helix backbone set up from repeating homochiral subunits.

The cause of muscle wasting and decreased plasma levels of branched chain amino acids (BCAA), valine, leucine, and isoleucine in liver cirrhosis is obscure. Here we have evaluated the effect of hyperammonemia. Rats were infused with either an ammonium acetate/bicarbonate mixture, a sodium acetate/bicarbonate mixture, or saline for 320 minutes. The parameters of leucine and protein metabolism were evaluated in the whole body and in several tissues using a primed constant intravenous infusion of L-[1-14C]leucine. Ammonium infusion caused an increase in ammonia and glutamine levels in plasma, a decrease in BCAA and alanine in plasma and skeletal muscle, a significant decrease in whole-body proteolysis and protein synthesis, and an increase in leucine oxidized fraction. A significant decrease in protein synthesis after ammonium infusion was observed in skeletal muscle while a nonsignificant effect was observed in liver, gut, heart, spleen, and kidneys. We conclude that the decrease in plasma BCAA after ammonia infusion is associated with decreased proteolysis and increased leucine oxidized fraction.

Conversion of the easily accessible racemic bis(amino acid)s cis- and trans-2a into the (S)-enantiomers via the corresponding Schiff bases with (1S,2S,5S)-2-hydroxy-3-pinanone is described. Condensation of the N-Boc-protected bis(amino acid)s with esters of the corresponding axially chiral amino acids (R)- and (S)- 1b afforded tetraspiro-substituted bis(dioxopiperazine)s 7 representing a rare case of primary helical topology. Absolute configuration of the products was assigned by NMR and CD spectra and confirmed by X-ray analysis of the Schiff base (S)-cis- 3 .

The title (R)-diacid has been found to self-assemble as hydrogen-bonded cyclotetramers in solution as well as in the solid phase; in the crystal the tetramers are stacked into chiral columns. In contrast, the racemic diacid forms infinite zig-zag chains of molecules of alternating chirality.

The reaction of unsubstituted as well as 6,6′-disubstituted biphenyl-2,2′-dicarboxaldehydes with HCN and ammonia or methylamine has been investigated. It has been found that the final reaction step, the addition of HCN to the intermediary cyclic imino nitriles, is a strictly diastereoselective process, yielding always only one of the two diastereoisomers of the title products, the stereoselection being controlled by the chiral twist of the biaryl axis.

NEO research is a great challenge just now - for science, for exploration and for planetary defence. Therefore NEO discoveries, astrometric follow-up, orbit computations as well as physical studies are of high interest both to science community and humankind.The KLENOT Project of the Klet Observatory, South Bohemia, Czech Republic pursued the confirmation, early follow-up, long-arc follow-up and recovery of Near Earth Objects since 2002. Tens of thousands astrometric measurements helped to make inventory of NEOs as well as to understand the NEO population. It ranked among the world most prolific professional NEO follow-up programmes during its first phase from 2002 to 2008. The fundamental improvement of the 1.06-m KLENOT Telescope was started in autumn 2008. The new computer controlled paralactic mount was built to substantially increase telescope-time efficiency, the number of observations, their accuracy and limiting magnitude.The testing observations of the KLENOT Telescope Next Generation (NG) were started in October 2011. The new more efficient CCD camera FLI ProLine 230 was installed in summer 2013. The original Klet Software Package has been continually upgraded over the past two decades of operation. Along with huge hardware changes we have decided for essential changes in software and the whole KLENOT work-flow. Using the current higher computing power available, enhancing and updating our databases and astrometry program, the core of our software package, will prove highly beneficial. Moreover, the UCAC4 as the more precise astrometric star catalog was implemented. The modernized KLENOT System was put into full operation in September 2013. This step opens new possibilities for the KLENOT Project, the long-term European Contribution to Monitoring and Cataloging Near Earth Objects.KLENOT Project Goals are confirmatory observations of newly discovered fainter NEO candidates, early follow-up of newly discovered NEOs, long-arc follow-up astrometry of NEOs in need of further data. The higher priority is given to Potentially Hazardous Asteroids (PHAs) and Virtual Impactors (VIs), recoveries of NEOs in the second opposition and also follow-up astrometry of radar or mission targets, special follow-up requests and follow-up astrometry of other unusual objects (comets, bright TNOs) including analysis of cometary features of suspected bodies, and also search for new asteroids, especially NEOs as well as other objects showing unusual motion.The KLENOT Telescope is located at the Klet Observatory, South Bohemia, Czech Republic (Central Europe), at geographical position: latitude 14° 17' 17” E, longitude 48° 51' 48”N, elevation 1068 meters above sea level, in a rather dark site in the middle of the Protected Landscape Area Blanský les. Average number of clear nights per year about 120. Our IAU/MPC code is 246KLENOT Project Advantages: •full observing time is dedicated to the KLENOT team•quick changes in an observing plan possible, even during an observing night•long-term NEO activities at Klet (since 1992)•experienced observers/measurers visually validate each moving object candidate•real-time processing of targeted objectsKLENOT Next Generation Telescope technical data (since 2013): •new computer controlled paralactic mount•1.06-m f/3 main mirror (Zeiss)•four lenses primary focus corrector•1.06-m f/2.7 optical system•CCD camera FLI ProLine PL230•chip e2v 2048 × 2048 pixels, pixel size 15 microns, Peltier cooling•FOV 37 × 37 arcminutes, image scale 1.1 arcseconds per pixel•limiting magnitude mV=21.5 mag. for 120-sec exposure timeKLENOT Project First Phase Results(2002-2008)total of 52,658 astrometric measurements of 5,867 bodies, it contains: •13,342 astrometric measurements of 1,369 NEAs (MPC,NEODys)•confirmation and astrometry of 623 NEAs from NEOCP (MPECs)•recoveries of 4 comets and 16 NEAs (including 196P/Tichý)•astrometry of 157 Virtual Impactors (CLOMON, SENTRY)•detection of cometary features of 34 bodies (IAUCs)•discovery of splitting of comet C/2004 S1 (Van Ness)•independent discovery of 4 fragments of comet 73P/S-W 3•asteroid discoveries - 750 bodies•3 NEOs - Apollo 2002 LK, Aten 2003 UT55, Apollo 2006 XR4, 1 JFA 2004 RT109The first KLENOT Project Next Generation Results (since 2011)total of 10,054 astrometric measurements of 1,298 bodies, it contains: •2,211 astrometric measurements of 263 NEAs(MPC,NEODys)•confirmation and astrometry of 143 NEAs from NEOCP (MPECs)•astrometry of 18 Virtual Impactors (CLOMON, SENTRY)•detection of cometary features of 5 bodies (IAUCs)

The optically active amino acids (R)-7 and (S)-8 were prepared as the first representatives of ω-amino acids possessing a biaryl axis as the sole element of chirality.

A straightforward synthetic approach to a new class of molecules with helical chirality has been developed involving an intramolecular [2 + 2 + 2] cycloisomerization of triynes under CpCo(CO)2/PPh3...

The axially chiral bis(α-amino acid)s cis-2 and trans-2 as possible building blocks for polymeric structures of novel type of helicity were prepared. Their configuration has been determined by NMR spectroscopy and, in the case of the trans-isomer, confirmed by single-crystal X-ray diffraction. Analogous pair of stereoisomeric diacids cis-3 and trans-3, devoid of the amino groups, was also prepared and their configuration assigned. The observed differences in the NMR spectra of cis- and trans-isomers of 2 and 3 are discussed from the viewpoint of their different symmetry properties.

The racemic as well as optically active dilactams 1 and 2 were prepared as the first representatives of axially chiral dilactams possessing a biaryl axis as the sole element of chirality. Their absolute configurations and inversion barriers were determined. The molecular structure and supramolecular self-assembly of the racemic dilactams directed by hydrogen bonding and aryl–aryl stacking was elucidated by single crystal diffraction analysis.

Crystal structures of the title compounds were determined by single crystal X-ray diffraction. Absolute configuration of the barium salt of (+)-(S)-acid was revealed by means of the Bijvoet's method. Compared to theoretical calculations, the conformations in the solid state are severely influenced by hydrogen bonding and/or coordination to barium ion. In all the crystal structures investigated except the racemic acid, there are two distinct bipyridine rotamers differing in the torsion angle around the biaryl axis and corresponding to syn-clinal and anti-clinal arrangements. The self-assembly patterns of the free (optically active as well as racemic) acids are closely similar: in crystal, their molecules are organized in layers by short intermolecular hydrogen bonds between the hydroxyl and the N-oxide. In contrast, the supramolecular patterns of the corresponding barium salts differ totally from each other. The anions are coordinated to barium through their oxygen atoms by four different modes, from monodentate to η 6, μ 6. This, together with the coordination of terminal and bridging water molecules, results in octa-, nona- and decacoordinated barium ions arranged in polymeric chains (in the S-salt) or layers (in the R,S-salt), linked by hydrogen bonds.

The title optically active diacids (R)-I and (S)-II of known absolute configuration were investigated as selectors in HPLC separation of enantiomers. With a standard set of benzamido alcohols and biaryl compounds, the separation was less efficient and less general than that found for selectors based on studied previously.

The title induction has been observed in the reaction of achiral 2,2',6,6'-tetrakis(bromomethyl)biphenyl with centrally chiral (R)-1-phenylethylamine, (R)-1-(1-naphthyl)ethylamine and (R)-1-(2-naphthyl)ethylamine. The ratio of the arising diastereomeric doubly bridged diamines and their thermodynamic stability have been determined. The diastereomer excess in the kinetically controlled reaction is solvent-dependent. The absolute configuration of the biphenyl twist in the products has been assigned on the basis of CD spectra and comparison with singly bridged biphenyl models of known sense of the twist.

We investigate amide nonplanarity in vibrational optical activity (VOA) spectra of tricyclic spirodilactams 5,8-diazatricyclo[6,3,0,0(1,5)]undecan-4,9-dione (I) and its 6,6',7,7'-tetradeuterio derivative (II). These rigid molecules constrain amide groups to nonplanar geometries with twisted pyramidal arrangements of bonds to amide nitrogen atoms. We have collected a full range vibrational circular dichroism (VCD) and Raman optical activity (ROA) spectra including signals of C-H and C-D stretching vibrations. We report normal-mode analysis and a comparison of calculated to experimental VCD and ROA. The data provide band-to-band assignment and offer a possibility to evaluate roles of constrained nonplanar tertiary amide groups and rigid chiral skeletons. Nonplanarity shows as single-signed VCD and ROA amide I signals, prevailing the couplets expected to arise from the amide-amide interaction. Amide-amide coupling dominates amide II (mainly C'-N stretching, modified in tertiary amides by the absence of a N-H bond) transitions (strong couplet in VCD, no significant ROA) probably due to the close proximity of amide nitrogen atoms. At lower wavenumbers, ROA spectra exhibit another likely manifestation of amide nonplanarity, showing signals of amide V (δ(oop)(N-C) at ~570 cm(-1)) and amide VI (δ(oop)(C'═O) at ~700 cm(-1) and ~650 cm(-1)) vibrations.

The title compound 4 , possessing a biaryl axis as the sole source of chirality, has been prepared in the enantiomerically pure ( R ) as well as racemic form by two alternative procedures starting from dibromide 1 .

We present preliminary results obtained with the European Observation Network. This network consists of 9 observatories in the Czech Republic, Germany and Bulgaria and has been involved in the BACODINE activities since April 1, 1994. We also discuss related problems such as the background of unknown variable stars and suggest a strategy for work in this area.

The title racemic acid (±)- 1 , prepared by hydrogen peroxide oxidation of 2,2′-bipyridine-3,3′-dicarboxylic acid, was resolved via the brucine salts. The absolute configuration of acid (+)- 1 was determined by X-ray diffraction study of its barium salt using the Bijvoet's anomalous dispersion method. The activation energy ΔG # for interconversion of enantiomers of the dimethyl ester 2 was found to be −106.5 kJ/mol at 50 °C.

The Kleť search programme for minor planets using 0,63m Maksutov camera of Kleť Observatory was begun in 1977 as a long-term project continuing up to the present day. The discovery frequency according to seasons in the year shows multiple differences between particular months.

The title optically active diacid I has been prepared as a potential selector for chiral stationary phase in the HPLC separation of enantiomers.

Axially chiral biaryl stationary phases (CSPs) of C2 symmetry bound to 3-aminopropyl silica both by ionic and covalent bond were prepared. The separation effectivity of the CSPs so obtained was investigated using 2-acylamino alcohols and biaryl derivatives as analytes. Whereas ionically bound phases derived from biphenyl-2,2'-dicarboxylic or 2,2'-bipyridine-3,3'-dicarboxylic acids (CSP 1, 2, 3 and 4) generally exhibited good resolving performance for 2-acylamino alcohols, they were ineffective for biaryl derivatives. On the other hand, covalent CSPs showed poor selector properties with acylamino alcohols; the binaphthyl CSP 7 resolved some of the biaryl analytes. Phase CSP 6 was completely inactive toward all the compounds tested. Absolute configuration of 4,4',6,6'-tetranitrobiphenyl-2,2'-dicarboxylic acid (II) has been derived from its CD spectrum and some speculations on configuration of bipyridine diacid IV are presented.

( R )-(+)-6,6′-Dinitrobiphenyl-2,2′-dicarboxylic acid, ionically bonded to 3-aminopropylsilanized silica (CSP 1), is the first ionically bonded axially chiral phase of C 2 symmetry. The phase is specifically efficient for the separation of a wide range of enantiomeric vicinal benzamido alcohols, whether open-chain, cyclic or polycyclic. To assess the steric and polar effects of the 6,6′-substituents, the performance of CSP 1 is compared with that of the analogous (but less effective) phase CSP 2, based on ( S )-(+)-6,6′-dimethylbiphenyl-2,2′-dicarboxylic acid. Some conclusions about the relation between the separation effectivity and the analyte structure, as well as about the factors involved in the chiral recognition process, are given.

Sera containing IgD paraprotein present problems in identifying patients with monoclonal gammopathies because only a small or even no spike may be present on standard serum protein electrophoresis. We have detected heavy chains of IgD monoclonal protein by means of high resolution two-dimensional gel electrophoresis. Besides clearly identifying delta heavy chains in maps of serum proteins, we also found size and charge heterogeneity of monoclonal immunoglobulins. The results demonstrate the usefulness of two-dimensional gel electrophoresis in the analysis of selected cases of immunoglobulin malignancies.

Background: Quantification of monoclonal immunoglobulin free light chains (FLCs) in serum is used increasingly in clinical practice for the diagnosis, prognostic assessment, and treatment monitoring of monoclonal gammopathies. It is used as an adjunct to standard serum protein electrophoresis and immunofixation. However, methods for FLC quantification need further standardization and validation. Methods: The Czech Myeloma Group and the Czech Society of Clinical Biochemistry have initiated an interlaboratory study where six laboratories collaborating with the primary myeloma treatment centres measured FLC concentrations in 12 serum samples from patients with monoclonal gammopathies. Results: Repeatability of the measurements in five laboratories was calculated based on differences between the results of duplicate measurements. We found that repeatability depended more on the laboratory than on the device used for measurement. Conclusions: The study revealed several weak points in the methodology, including the need for a uniform sample dilution procedure. Interlaboratory reproducibility was comparable with values achieved in the NEQAS programme. Because the κ/λ ratio cannot be measured with high precision, κ and λ FLC concentrations should be used where possible. Due to its impact on the clinical management of patients with gammopathy, FLC quantification needs to become a part of the regular quality control cycle in myeloma centres.