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Notes: Abstract The cerebrospinal fluid (CSF) of 37 patients with early Lyme neuroborreliosis (ELN) and of 10 patients with late Lyme neuroborreliosis (LLN, duration of symptoms ≥ 7 months) was investigated for typical features differentiating between acute and chronic courses of disease. Individual patients were studied after 2 and 4 weeks, and 3, 6, and 12 months. Patients with ELN presented predominantly with symptoms of the peripheral nervous system, while patients with LLN generally suffered from symtoms of the central nervous system. At the first lumbar puncture, patients with ELN revealed a more intense pleocytosis in the CSF (P 〈 0.02) and a higher intrathecal synthesis of total IgM (P 〈 0.0003) and ofBorrelia burgdorferi-specific IgM antibodies (P 〈 0.01). At the same time, in patients with LLN, the blood-CSF barrier was more severely impaired (P = 0.03), and local production of total IgG (P = 0.0001), ofB. burgdorferi-specific IgG antibodies (P = 0.03) and of total IgA (P = 0.001) was more markedly increased. The quantity of intrathecally producedB. burgdorferi-specific IgA antibodies did not differ between the two study groups. Clinical recovery was usually accompanied by a considerable improvement of the blood-CSF barrier function and pleocytosis. After 6 months, the intrathecal synthesis of total IgG had significantly decreased in patients with ELN but not in those with LLN. At the same time, the CSF of most patients in both study groups still contained intrathecally producedB. burgdorferi-specific IgG antibodies. In the absence of clinical illness or symptoms of inflammation 6 and 12 months after treatment,B. burgdorferi-specific IgG antibodies in the CSF might simply indicate an anamnestic reaction to a previous infection of the central nervous system. Six months after antibiotic treatment, patients with ELN still revealed evidence of intrathecal synthesis of total IgM, whereas those with LLN did not. These antibodies, however, were not related toB. burgdorferi.

Notes: Abstract Within the framework of the constituent quark model we discuss the effects of different types of meson-baryon-baryon vertex operators on the form factors and the coupling strengths of the lowest-lying positive and negative parity non-strange baryons. We compare the quark pair creation model (3P0-model) with the SU(6)-model in which mesons are treated as elementary fields that directly couple to the quarks. The latter model is employed both in the so-called static limit and in a modification motivated by Galilei invariance. It is demonstrated that the inclusion of non-static effects simulates some features of the3P0 vertex. Especially the reaction πN→ππN is found to be very sensitive to the different assumptions on the dynamics of theq¯q pair creation process. More indirect hints for the internal structure of the mesons might be obtained from the predicted asymmetry for the two form factors ofN→Δ+π andΔ→N+π, which occurs in the3P0-model, only.

Notes: Abstract Genetic information contributing to cystic fibrosis in addition on the CF gene is suggested to reside on the long arm of the human chromosome 7. In our attempt to analyze this genomic region in detail, we generated a region-specific DNA probe library by microdissection and microcloning of the midpiece of the chromosome 7q arm. Microdissection was performed in unstained metaphase spreads from a human × mouse hybrid cell line containing chromosome 7 as the only human chromosome. We obtained 593 clones from 75 dissected chromosomal fragments. At least 88% of the microclones were true recombinants; 40% of the clones contained repetitive sequences as determined by plaque hybridization with genomic DNA as probe. The overall mean fragment size of insert fragments was 3.2 kb, the median size was 3.5 kb. Regional mapping of 30 DNA fragments was performed by the aid of hybrid cell lines containing different segments of human chromosome 7; 50% of the microcloned inserts were found to map to 7q22-32.

Notes: Abstract This paper describes an experiment where the Hanle effect in the ground state of an atomic transition is detected, not by a modification of the light absorbed or reemitted by the atoms, but by a modification of the atomic trajectories. The experimental results are compared with the theoretical predictions of two calculations, the first one considering only the steady-state regime, the second one including the effects of the transient phenomena which take place when the atom enters the laser beam.

Notes: Abstract Extremely cold antiprotons, stored in a Penning trap at 4 K, open the way toward the production and study of cold antihydrogen. We have begun experimentally investigating the possibility to recombine cold positrons and antiprotons within nested Penning traps. Trap potentials are adjusted to allow cold trapped protons (and positive helium ions) to pass through cold trapped electrons. Electrons, protons and ions are counted by ejecting them to a cold channel plate and by nondestructive radiofrequency techniques. The effect of the space charge of one trapped species upon another trapped species passing through is clearly observed.

Notes: Summary The purpose of the study was to develop a micro HPLC system with physically changeable selectivity. This was done using two series-coupled beds of chemically differing stationary phases in a packed fused silica column. The selectivity change, in fine repeatable steps, was possible by the stepwise moving of a tube oven, covering only 50% of this “tandem column”. Each step of selectivity started with a position change of the oven, thus heating up a fresh position of the more polar and the non-polar column bed. As the chromatogram is thus repeated under these new selectivity conditions, multiple chromatograms result. For this reason we call the technique “Multi Micro HPLC”. This very simple mode of operation provides an analytical tool for developing separation conditions and which allows optimizing for a given special sample and checking for one of the most critical problems in HPLC: unidentified peak overlapping. The selectivity changes are nonlinearly correlated with the oven position with regards to temperature field distribution and are greater than is possible by simple change of column temperature. Micropacked columns are ideal for quick temperature changes. Elevated temperatures in HPLC help to shorten analysis time. The concepts discussed above provide an explanation of how a normal, formerly chemically homogeneous, column can become very temperature sensitive after detoriation at the inlet. In fact the column has become an unintentional “tandem column” and peak positions tend to move erratically as its selectivity changes drastically by inhomogeneous temperature changes along the separation path.

Notes: Summary Planar electrochromatographic separations of test substances were performed on non pre-wetted, commercially available, thin-layer plates. The behavior of different layers and solvents was studied in an applied electric field of up to 2000 V cm−1. Evident electrokinetic effects, electroosmosis and electrophoresis were observed only on silica gel and polyamide layers developed with polar solvents. The selectivity of separation of nonionic and ionogenic compounds was greatly enhanced. Although experimental conditions were controlled to a certain extent, results obtained with the same solvents were reproducible within 5%.

Notes: The capabilities of an ion trap mass spectrometer (ITMS) in determining the molecular weights and characterizing the primary sequences of peptides are explored. Ionization is accomplished by Cs+ desorption of the sample in a liquid matrix or by laser desorption from a solid matrix and is performed externally to the ion trap, which is operated with mass/charge range extension using resonance ejection. The mass spectra recorded in this way are dominated by the protonated molecules and are relatively free of the chemical noise normally associated with liquid secondary ion mass spectrometry (SIMS) or fast atom bombardment ionization. The matrix-assisted laser desorption spectra are of comparable quality to those obtained with Cs+ SIMS. The molecular weights of a variety of model peptides are measured with a resolution of 103 (FWHM) and a mass measurement accuracy of 0.1%, using mass analysis scan speeds in the 103-104 Da s-1 range. By slowing the scan speed by factors as large as 1000, better than unit resolution is achieved for all the compounds examined and, in the case of gramicidin S, a resolution of more than 105 has been recorded.Tandem mass spectrometry (MS/MS) is performed by isolating the protonated molecule in the trap using a reverse-then-forward scan and then irradiating it by resonance excitation to cause collision-induced dissociation. The product ion tandem mass spectrum is then recorded by the usual resonant ejection scan. Dissociation efficiencies are very high (〉50%) and the product spectra are dominated by the fragments of amide bond scission together with associated CO losses (y, b and a-type fragments). In addition, internal cleavage products are also observed. Peptides such as prepro-VIP/PHM, renin substrate and glu-ribinopeptide give tandem spectra which are dominated by y ions, whereas other peptides, such as α-endorphin, give principally b-type fragment ions. The cyclic peptides, gramicidin S and the antibiotic actinomycin D, give spectra dominated by amide bond cleavages. Additional structural information, especially in the low-mass region, is sometimes desirable and can be provided by recording MS3 spectra. This can be done using little additional sample or analysis time. The high-resolution capabilities available by slowing the mass analysis scan time are applied to the MS/MS experiment, allowing unit resolution to be achieved, both in selecting the molecular ion and in recording the product ion spectrum. It is also shown that the higher-resolution resonant excitation experiment does not require isolation of the individual isotopic forms of the protonated molcule in order to provide an isotopically selective product spectrum. Sample sizes loaded onto the probe for MS/MS experiments are typically 〈 1 pmol and the data acquisition time is usually much shorter than the sample life-time.Shortcomings of the method include limitations common to desorption ionization (analyte suppression effects and reactions in the matrix) as well as the need to calibrate the mass scale with an external standard which results in mass measurement accuracies which, at present, are ±0.1%. A summary is given of steps which are being taken to improve mass measurement accuracy, to deposit increased internal energies to cause more extensive fragmentation, and to improve our understanding of ion traps through simulations of ion motion.