Cytokine regulation of IL-1 beta gene expression in the human polymorphonuclear leukocyte

Although recently polymorphonuclear leukocytes (PMN) have been identified as producers of IL-1 beta in response to LPS and granulocyte/monocyte colony stimulating factor, little is known regarding the ability of other cytokines to induce the production of IL-1 beta in the PMN. Inasmuch as IL-1 and TNF have been shown to be important priming agents, as well as agents that induce migration of PMN, we investigated their effect on IL-1 beta gene expression in human peripheral blood PMN. In the present study, we demonstrate that human peripheral blood PMN produce IL-1 beta in response to IL-1 alpha, IL-1 beta, and TNF-alpha. Control (unstimulated) human PMN had virtually undetectable levels of IL-1 beta mRNA. Either IL-1 beta or TNF, induced PMN to transiently express IL-1 beta mRNA with peak expression at 1 h, returning to untreated levels by 2 h. A dose response indicated that as little as 0.05 ng/ml of IL-1 beta or TNF resulted in IL-1 beta induction, with maximal effects at 1 ng/ml of IL-1 beta and 5 ng/ml of TNF. IL-1 alpha or IL-1 beta exhibited similar dose responses in IL-1 beta mRNA induction. Inasmuch as cytokines have been shown to have synergistic effects in cell function studies, we induced PMN with a combination of maximally effective doses of TNF plus IL-1 beta. They demonstrated a cooperative effect on IL-1 beta gene expression, in that mRNA levels were sustained for three hours. IL-1 beta Ag expression, as measured by ELISA, paralleled IL-1 beta mRNA expression with cell associated peak levels at 2 to 4 h. IL-1 beta Ag levels in PMN lysates and supernatants correlated with IL-1 beta mRNA levels, i.e., TNF + IL-1 greater than TNF greater than IL-1. Thus, these studies represent the first demonstration of IL-1 and TNF induction of IL-1 beta gene expression in the PMN. Furthermore, the time course of induction is unique to the PMN, with peak induction of mRNA at 1 h, which is consistent with the short lived nature of these cells in inflammatory lesions.     

Phylogeny of Greya (Lepidoptera: Prodoxidae), based on nucleotide sequence variation in mitochondrial cytochrome oxidase I and II: congruence with morphological data

The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from nucleotide sequence variation across a 765-bp region in the cytochrome oxidase I and II genes of the mitochondrial genome. Most parsimonious relationships of 25 haplotypes from 16 Greya species and two outgroup genera (Tetragma and Prodoxus) showed substantial congruence with the species relationships indicated by morphological variation. Differences between mitochondrial and morphological trees were found primarily in the positions of two species, G. variabilis and G. pectinifera, and in the branching order of the three major species groups in the genus. Conflicts between the data sets were examined by comparing levels of homoplasy in characters supporting alternative hypotheses. The phylogeny of Greya species suggests that host-plant association at the family level and larval feeding mode are conservative characters. Transition/transversion ratios estimated by reconstruction of nucleotide substitutions on the phylogeny had a range of 2.0-9.3, when different subsets of the phylogeny were used. The decline of this ratio with the increase in maximum sequence divergence among taxa indicates that transitions are masked by transversions along deeper internodes or long branches of the phylogeny. Among transitions, substitutions of A-->G and T-->C outnumbered their reciprocal substitutions by 2-6 times, presumably because of the approximately 4:1 (77%) A+T-bias in nucleotide base composition. Of all transversions, 73%-80% were A<-->T substitutions, 85% of which occurred at third positions of codons; these estimates did not decrease with an increase in maximum sequence divergence of taxa included in the analysis. The high frequency of A<-->T substitutions is either a reflection or an explanation of the 92% A+T bias at third codon positions.      

The mitochondria ofPolytoma papillatum at two different stages of the vegetative cell cycle

Summary The examination of adjacent sections ofPolytoma papillatum cells by the electron microscope enabled us to construct three dimensional models of the chondriomes. These reconstructions show that in two predivision cells the chondriome primarily consists of one large and highly convoluted mitochondrion. One and three small ovoid mitochondria also exist. Examination of two new daughter cells reveales 30 and 47 mitochondria of various shapes and sizes. This indicates that during the growth phase ofPolytoma (vegetative cell cycle) preponderantly one mitochondrion is formed by fusion of those numerous mitochondria found after cell cleavage. Our observations will be compared with results on this subject in other organisms.We are greatly indebted to Prof. Dr. C. G.Arnold (Erlangen) for his support in this work.     

Acute poisoning from gamma-hydroxybutyrate in California.

We report a series of 5 representative patients in California who experienced adverse reactions from the illicitly marketed substance gamma-hydroxybutyrate (GHB). The drug is a putative neurotransmitter marketed as a growth hormone releaser for bodybuilders. The most commonly reported symptoms included abrupt drowsiness, dizziness, and a "high". Other effects were headache, nausea, vomiting, myoclonic jerking, and short-term coma. There have been no reported deaths. If product use is discontinued, full recovery with no long-term side effects is universal. No clear dose-response effect was observed; this may be attributable to differences in susceptibility, wide variations in doses taken by the same person, or the coingestion of other substances. Case interviews confirm that, despite being banned by the US Food and Drug Administration, GHB is still widely available in the underground drug market. Athletes and bodybuilders may take drugs for which there are claims of improved performance or body image. Physicians should be alert for signs of GHB poisoning in emergency department and clinic patients.     

Epitope Predictions Indicate the Presence of Two Distinct Types of Epitope-Antibody-Reactivities Determined by Epitope Profiling of Intravenous Immunoglobulins

Epitope-antibody-reactivities (EAR) of intravenous immunoglobulins (IVIGs) determined for 75,534 peptides by microarray analysis demonstrate that roughly 9% of peptides derived from 870 different human protein sequences react with antibodies present in IVIG. Computational prediction of linear B cell epitopes was conducted using machine learning with an ensemble of classifiers in combination with position weight matrix (PWM) analysis. Machine learning slightly outperformed PWM with area under the curve (AUC) of 0.884 vs. 0.849. Two different types of epitope-antibody recognition-modes (Type I EAR and Type II EAR) were found. Peptides of Type I EAR are high in tyrosine, tryptophan and phenylalanine, and low in asparagine, glutamine and glutamic acid residues, whereas for peptides of Type II EAR it is the other way around. Representative crystal structures present in the Protein Data Bank (PDB) of Type I EAR are PDB 1TZI and PDB 2DD8, while PDB 2FD6 and 2J4W are typical for Type II EAR. Type I EAR peptides share predicted propensities for being presented by MHC class I and class II complexes. The latter interaction possibly favors T cell-dependent antibody responses including IgG class switching. Peptides of Type II EAR are predicted not to be preferentially presented by MHC complexes, thus implying the involvement of T cell-independent IgG class switch mechanisms. The high extent of IgG immunoglobulin reactivity with human peptides implies that circulating IgG molecules are prone to bind to human protein/peptide structures under non-pathological, non-inflammatory conditions. A webserver for predicting EAR of peptide sequences is available at www.sysmed-immun.eu/EAR.     

Integrated L-phenylalanine separation in an E. coli fed-batch process: from laboratory to pilot scale

Pilot-scale reactive-extraction technology for fully integrated L-phenylalanine (L-Phe) separation in Escherichia coli fed-batch fermentations was investigated in order to prevent an inhibition of microbial L-Phe production by-product accumulation. An optimal reactive-extraction system, consisting of an organic kerosene phase with the cation-selective carrier DEHPA (di-2-ethylhexyl phosphonic acid) and an aqueous stripping phase including sulphuric acid, was found particularly efficient. Using this system with two membrane contactors, mass-transfer coefficients of up to 288 x 10(-7) cm s(-1) for the aqueous/organic and 77 x 10(-7) cm s(-1) for the organic/stripping phase were derived from experimental data using a simple modelling approach. Concentration factors higher than 4 were achieved in the stripping phase as compared to the aqueous donor phase. Reactive extraction enabled a 98% cation portion of L-Phe in the stripping phase, leading to final product purity higher than 99% after L-Phe precipitation. A doubling of L-Phe/glucose yield was observed when kerosene/DEHPA was added to the fermentation solution in the bioreactor to experimentally simulate a fully integrated L-Phe separation process.     

Analysis of plastid DNA-like sequences within the nuclear genomes of higher plants

A wide-ranging examination of plastid (pt)DNA sequence homologies within higher plant nuclear genomes (promiscuous DNA) was undertaken. Digestion with methylation-sensitive restriction enzymes and Southern analysis was used to distinguish plastid and nuclear DNA in order to assess the extent of variability of promiscuous sequences within and between plant species. Some species, such as Gossypium hirsutum (cotton), Nicotiana tabacum (tobacco), and Chenopodium quinoa, showed homogenity of these sequences, while intraspecific sequence variation was observed among different cultivars of Pisum sativum (pea), Hordeum vulgare (barley), and Triticum aestivum (wheat). Hypervariability of plastid sequence homologies was identified in the nuclear genomes of Spinacea oleracea (spinach) and Beta vulgaris (beet), in which individual plants were shown to possess a unique spectrum of nuclear sequences with ptDNA homology. This hypervariability apparently extended to somatic variation in B. vulgaris. No sequences with ptDNA homology were identified by this method in the nuclear genome of Arabidopsis thaliana.      

Bilateral song production in domestic canaries

We studied the mechanism of song production in the outbred common or domestic canary (Serinus canaria). The contribution that each side of the syrinx makes to song was investigated by observing the effect of unilaterally occluding the left or right primary bronchus, followed by section of the ipsilateral branch of the tracheosyringeal nerve. In other birds with a bilaterally intact vocal system we monitored airflow through each side of the syrinx, together with subsyringeal pressure, during spontaneous song. Song production by domestic canaries is not strongly lateralized as it is in the conspecific song-bred waterslager strain. Some syllables are produced entirely on the left or right side of the syrinx, whereas others contain sequential contributions from each side. Low fundamental frequencies are produced with the left syrinx and high frequencies by the right syrinx, increasing the frequency range of domestic canary song compared to that of the waterslager strain. Midrange frequencies can be generated by either side. Syllables at repetition rates below about 25 s(-1) were accompanied by minibreaths, which were usually bilateral. Unilateral minibreaths were typically on the left side. At higher syllable repetition rates, minibreaths were replaced by a respiratory pattern of pulsatile expiration. Our data show that strong unilateral dominance in song production, present in the waterslager strain, is not a trait of the species as a whole and that the pattern of song lateralization can be altered by selective breeding for particular song characteristics.