Jet-cooled diode laser spectra of CF3Br in the 9.2 microm region and rovibrational analysis of symmetric CF3 stretching mode.

Pulsed slit-jet high resolution (up to 0.0009 cm(-1) FWHM) infrared diode laser spectra of CF(3)Br, with natural isotopic abundance, were obtained in the region around 9.2 microm at the rotational temperature of about 50 K. In addition, diode laser spectra at reduced temperature (200 K) were recorded. We present here the rovibrational analysis of the nu(1) fundamental in the range 1075-1090 cm(-1). The fine structure of many P(J) and R(J) clusters has been well resolved for the first time. The assignment of rovibrational transitions has been accomplished up to K = 27, J = 63 for CFBr and K = 33, J = 62 for CFBr. A total of 636 (CFBr) and 880 (CFBr) lines were used in the final fit and a very accurate set of molecular constants, including the quartic centrifugal distortion coefficients for the v(1) = 1 state of both the bromine isotopologues, was obtained. In addition, spectral features belonging to the nu(1) + nu(6)-nu(6) hot band were unambiguously identified and a set of spectroscopic parameters were determined.

Rovibrational Study of the CH(2) Wagging Fundamental of Monofluoroacetonitrile.

The vapor-phase infrared spectrum of monofluoroacetonitrile (CH(2)FCN) has been recorded at high resolution in the nu(4) band region (1363-1398 cm(-1)) using a tunable diode laser spectrometer. A detailed assignment of the rotational structure of the expected a-/b-hybrid band has been made for a-type transitions with K(a)

High-resolution rovibrational analysis of the Nu4 band of cis-1,2-difluoroethylene.

The diode laser spectrum of cis-1,2-CHF=CHF has been measured and analyzed in the nu4 fundamental region near 1016 cm(-1). This vibration of symmetry species A1 corresponds to the C-F symmetric stretching motion and gives rise to a strong b-type band. The rovibrational analysis, extended to the P, Q, and R branches, led to the identification of 2800 lines with J < or = 62, Ka < or = 18, Kc < or = 62. The assigned transitions free of major resonance contributions, fitted using Watson's A-reduction Hamiltonian in the Ir representation, yielded a set of spectroscopic parameters up to the quartic coefficients for the V4 = 1 state. Several perturbation effects occur throughout the band, mainly caused by the first-order c-type Coriolis interaction with the nu5 + nu11, vibrational state. Even though no transitions to the perturbing level were observed, the band orign and the rotational constants for the perturber were determined from a dyad model which includes the Coriolis interaction term.

Mass spectrometry of the human pituitary proteome: identification of selected proteins.

The field of proteomics involves the combined application of advanced separation techniques, mass spectrometry, and bioinformatics tools to characterize proteins in complex biological mixtures. Here we report the identification of nine proteins from the human pituitary proteome, using the proteomics approach. The pituitary proteins were separated by two-dimensional electrophoresis, and were visualized by silver staining. The proteins of interest were subjected to in-gel digestion with trypsin, and the masses of the resulting peptides were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This tryptic mass map was used to identify the proteins through a search of a protein-sequence database. The identified proteins include important hormones, and enzymes with various catalytic activities. These proteins will be used to construct a two-dimensional reference database of the human pituitary. This database will be employed to study changes in the pituitary proteome that are associated with the formation of pituitary tumors.

High-Resolution Infrared Laser Study of the nu(4) Absorption Band of cis-CHCl&dbond;CHF.

cis-1-Chloro-2-fluoroethylene was synthesized, and the gas-phase infrared spectrum was investigated in the nu(4) band region between 1321-1350 cm(-1), at a resolution of about 0.002 cm(-1), employing a tunable diode-laser spectrometer. This vibration of symmetry species A' gives rise to an a/b-hybrid band, even though our analysis pointed out that the intensity of the a-type component is predominant. Most of the J and K structure was resolved in different subbranches, and the rovibrational analysis led to the assignment of about 1900 a-type lines with J

Effects of muramyl peptides on macrophages, monokines, and sleep.

Muramyl peptides are fragments of peptidoglycan from the cell walls of bacteria. Because of their unique chemistry, the immune system recognizes that muramyl peptides are products of bacteria, and it responds by becoming activated to resist infection. This resistance to infection is nonspecific, and extends to unrelated species of bacteria, fungi, and viruses. A key mechanism of the resistance to infection is activation of macrophages. Macrophage activation results in increased production of microbicidal oxygen radicals like superoxide and peroxide, and in increased secretion of inflammatory cytokines like interleukin-1beta and tumor necrosis factor-alpha. These cytokines, besides activating neutrophils, B lymphocytes, and T lymphocytes, act on the central nervous system to induce physiological responses like fever and sleep. These physiological responses also aid in combating infection. Muramyl peptides also activate macrophages and other cells of the immune system to kill cancer cells. Muramyl peptides and similar agents will become more important as therapeutic agents in the future, due to increasing resistance of microbes to antibiotics, and increasing numbers of patients with immunodeficiencies.

Infrared Laser Spectroscopy of the nu4 and nu9 Band System of CH2F37Cl.

The spectra of CH2F37Cl (95% isotopically pure sample) have been recorded at high resolution with a tunable diode laser spectrometer in the regions 979-1030 and 1108-1136 cm-1. The spectral analysis allowed us to assign about 2000 lines (J

Diode Laser Spectroscopy of Trifluoroethylene in the 8.6-µm Region.

The two mid-infrared bands of the CF2&dbond;CHF molecule, nu5 centered at 1172.673 cm-1 and nu6 + nu9 at 1155.105 cm-1, were measured on a tunable diode laser spectrometer with a resolution near the Doppler limit. These vibrations of A' species give rise to a/b hybrid bands, even though our analysis has pointed out that the intensity of the a-type component is predominant. Most of the J and K structure has been resolved in different subbranches, and the rovibrational analysis led to the assignment of about 1400 (J

Structures of biologically active muramyl peptides from peptidoglycan of Streptococcus sanguis.

The structures of major muramyl peptides derived from peptidoglycan of the oral pathogen Streptococcus sanguis were determined and the biological activity of the peptides was tested in vitro on human monocytes. The muramyl peptides, produced by muramidase digestion of the purified peptidoglycan, were separated by reversed-phase high-performance liquid chromatography, either in their native form or after reduction with sodium borohydride. Chemical structures of the peptides were elucidated by a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, amino acid analysis, post-source decay analysis and Edman sequencing. The study revealed two distinct monomers: N-acetylglucosaminyl-N-acetylmuramyl-Ala-iGln-Lys(Ala-Ala) (1), where the Ala-Ala is connected to the epsilon-amino group of lysine, and N-acetylglucosaminyl-N-acetylmuramyl-Ala-iGln-Lys(Ala-Ala)-Ala-Ala (2), where an additional dialanyl residue is attached to the lysine alpha-carboxyl group. Two sets of higher oligomers (di-, tri- and tetramers), related structurally to monomers 1 or 2 were also detected. In these oligomers, the monomeric subunits are linked together by Ala-Ala-Ala bridges. The native muramyl peptides primed human monocytes in vitro for the increased production of the microbicidal superoxide radical.

High Resolution Infrared Spectrum of the C-F Stretching Mode of CH2 F37 Cl

Diode laser spectra of CH2 F37 Cl (95% isotopically pure sample) have been recorded in the 9.4 µm region characterized by the nu4 fundamental. The spectral analysis allowed the assignment of more than 3700 transitions with J

Analysis of the 2nu1 + nu2 + 2nu3 Band of Ozone

The 2nu1 + nu2 + 2nu3 band of ozone, occurring in the 4780 cm-1 region, has been observed for the first time, using a Fourier transform spectrometer, at 0.008 cm-1 resolution and using a large path length pressure product. Assignments of vibration-rotational transitions have been made up to J = 48 and Ka = 9. As a few levels with Ka = 1 or 2 are perturbed, it has been necessary to take into account the Coriolis resonance between the (212) and (141) vibrational states. With the effective Hamiltonian explicitly accounting for the interaction between these two states, the fit on 165 energy levels leads to the rms deviation of 1.9 x 10(-3) cm-1, which is near the experimental accuracy. Line intensities of the 2nu1 + nu2 + 2nu3 band have been measured and calculated. The set of spectroscopic parameters for interacting bands, as well as transition moment constants, is given. A complete list of line positions and intensities, with a cutoff of 1 x 10(-26) cm-1/molecule.cm-2 at 296 K up to J = 65 and Ka = 15, has been generated, which leads to the integrated band intensity Sv (2nu1 + nu2 + 2nu3) = (5.1 +/- 2.0) x 10(-23) cm-1/molecule.cm-2. Copyright 1997Academic Press

High-Resolution Infrared Spectrum of Vinyl Fluoride at 500 cm-1

The infrared spectrum of vinyl fluoride (CH2=CHF) has been investigated in the region 390-590 cm-1 at room temperature and at a resolution of 0.0016 cm-1 using a Fourier transform spectrometer. The rovibrational analysis of the spectral features allowed us to assign about 11 000 lines (J

Fast atom bombardment mass spectrometry of synthetic peptides.

Fast atom bombardment mass spectrometry plays a continuing and effective role in the rapid and efficient analysis of synthetic peptides. In this article, the basic principles of FAB-MS and FAB-MS/MS are reviewed, and the limitations and pitfalls of the method are discussed. The potential of the technique is illustrated by several selected applications. The molecular weight of a synthetic peptide can be readily and accurately determined by FAB-MS. The sensitivity of the FAB-MS method also makes it extremely useful for the evaluation of the purity of a peptide. FAB-MS/MS allows the elucidation of the primary structure of the target peptide, even in a mixture, and also permits the rapid identification of synthetic side products. Hence, FAB-MS and FAB-MS/MS aid in the unequivocal characterization of synthetic peptides. Furthermore, the information that is gained from the FAB analysis can help to unravel potential problems that may be associated with the synthesis.

Computerized pharmacy services in a large community hospital.

A computerized pharmacy system dealing with drug distribution, clinical services and administrative services is described. Present systems, implemented for 50% of the institution's beds, are discussed fully. Future applications of the system are outlined.