Neutrophil extracellular traps (NETs) are extracellular chromatin structures that can trap and degrade microbes. They arise from neutrophils that have activated a cell death program called NET cell death, or NETosis. Activation of NETosis has been shown to involve NADPH oxidase activity, disintegration of the nuclear envelope and most granule membranes, decondensation of nuclear chromatin and formation of NETs. We report that in phorbol myristate acetate (PMA)-stimulated neutrophils, intracellular chromatin decondensation and NET formation follow autophagy and superoxide production, both of which are required to mediate PMA-induced NETosis and occur independently of each other. Neutrophils from patients with chronic granulomatous disease, which lack NADPH oxidase activity, still exhibit PMA-induced autophagy. Conversely, PMA-induced NADPH oxidase activity is not affected by pharmacological inhibition of autophagy. Interestingly, inhibition of either autophagy or NADPH oxidase prevents intracellular chromatin decondensation, which is essential for NETosis and NET formation, and results in cell death characterized by hallmarks of apoptosis. These results indicate that apoptosis might function as a backup program for NETosis when autophagy or NADPH oxidase activity is prevented.

Chronic obstructive pulmonary disease (COPD) is a multiorgan systemic disease. The systemic features are skeletal muscle weakness and cachexia, the latter being associated with systemic inflammation. The exact mechanisms underlying skeletal muscle dysfunction in COPD remain obscure. Recent evidence suggests involvement of the peroxisome proliferatoractivated receptors (PPARs) and PPAR-c coactivator (PGC)-1a in regulation of skeletal muscle morphology and metabolism, and mitochondrial transcription factor A (TFAM) has been implicated in the process of mitochondrial biogenesis. The aim of the present exploratory study was, therefore, to compare these factors in the skeletal muscle of nine healthy control subjects and 14 COPD patients stratified by cachexia.PPAR-c, PPAR-d and TFAM were measured at the mRNA and protein level by real-time quantitative PCR and Western blotting, respectively. PPAR-a and PGC-1a were meansured at the mRNA level.PPAR-d and TFAM protein content, as well as PGC-1a mRNA levels, were decreased in the skeletal muscle of COPD patients compared with healthy controls. The cachectic COPD subgroup was further characterised by decreased PPAR-a mRNA expression and decreased TFAM protein and mRNA levels compared with noncachectic COPD patients. In addition, PPAR-a mRNA levels in skeletal muscle correlated negatively with inflammatory markers in plasma.Therefore, a disturbed expression of these regulatory factors may well underlie the disturbed skeletal muscle functioning in chronic obstructive pulmonary disease.

Two novel pore-forming peptides have been isolated from the venom of the South-African scorpion Opistophtalmus carinatus. These peptides, designated opistoporin 1 and 2, differ by only one amino acid and belong to a group of a-helical, cationic peptides. For the first time, a comparison of the primary structures of a-helical pore-forming peptides from scorpion venom was undertaken. This analysis revealed that peptides in the range of 40-50 amino acids contain a typical scorpion conserved sequence S(x) 3 KxWxS(x) 5 L. An extensive study of biological activity of synthesized opistoporin 1 and parabutoporin, a poreforming peptide previously isolated from the venom of the South-African scorpion Parabuthus schlechteri, was undertaken to investigate an eventual cell-selective effect of the peptides. Opistoporin 1 and parabutoporin were most active in inhibiting growth of Gram-negative bacteria (1.3-25 lM), while melittin and mastoparan, two well-known cytolytic peptides, were more effective against Gram-positive bacteria in the same concentration range. In addition, the peptides showed synergistic activity with some antibiotics commonly used in therapy. Opistoporin 1 and parabutoporin had hemolytic activity intermediate between the least potent mastoparan and the highly lytic melittin. Furthermore, all peptides inhibited growth of fungi. Experiments with SYTOX green suggested that this effect is related to membrane permeabilization.

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The overall meta-analysis provides additional quantitative evidence consistent with prior reviews focusing on other groups exposed to pesticides (farmers, pesticide applicators). The results again point to occupational exposure to pesticides as a possible risk factor for prostate cancer but the question of causality remains unanswered. Epidemiological evidence did not allow identifying a specific pesticide or chemical class that would be responsible for the increased risk but the strongest evidence comes from workers exposed to phenoxy herbicides possibly in relation with dioxin and/or furan contamination.

The increased meta-rate ratio for prostate cancer in agricultural pesticide applications provides additional evidence for a possible relationship between pesticide exposure and prostate cancer. The homogeneity observed between the individual rate ratios, after we had regrouped the data according to geographic location, tends to increase the consistency of the association. However, the data available from the individual studies do not provide sufficient exposure information for firm conclusions to be drawn about pesticide exposure as the cause of prostate cancer, independently from other factors.

Isolation of the human neutrophil activating protein (NAP) interleukin 8 (IL8) from leukocytes has revealed that it is structurally related to beta-thromboglobulin (beta TG) from platelets. Both these proteins occur as natural mixtures of multiple forms, differing from each other by unequal truncation at the NH2 terminus. In this study we have compared IL8 and beta TG forms for in vitro and in vivo neutrophil activation. In contrast to IL8, none of the beta TG forms were found to exert granulocyte chemotactic activity in vitro, as measured in the agarose assay. However, fractions rich in the most extensively processed forms of beta TG (e.g. NAP-2) as well as pure NAP-2 did induce lactoferrin release from granulocytes, whereas fractions containing only the longer forms (e.g. connective tissue-activating peptide III) were inactive. In order to observe this in vitro effect, about 10-fold less IL8 (10 nM) than NAP-2 was required. In the presence of a vasodilator substance low doses (2-20 pmol) of IL8 and the shorter forms of beta TG caused granulocyte accumulation and plasma leakage in rabbit skin whereas the longer forms of beta TG again failed to do so. Finally, granulocytosis induction following i.v. injection was found to occur with NAP-2. At the maximal dose tested (250 pmol), this in vivo effect of NAP-2 was less pronounced than that of IL8. In the case of IL8, NH2-terminal processing did not seem to affect granulocyte stimulatory activity. It should be noted, however, that the extent of processing of IL8 is less than that occurring with beta TG. It can be concluded that the platelet factor beta TG, structurally related to the monokine IL8, can also play a role in neutrophil activation during inflammatory reactions.

We measured in nine patients, poisoned by organophosphorus agents (ethyl parathion, ethyl and methyl parathion, dimethoate, or bromophos), erythrocyte and serum cholinesterase activities, and plasma concentrations of the organophosphorus agent. These patients were treated with pralidoxime methylsulphate (Contrathion), administered as a bolus injection of 4.42 mg.kg-1 followed by a continuous infusion of 2.14 mg.kg-1/h, a dose regimen calculated to obtain the presumed "therapeutic" plasma level of 4 mg.l-1, or by a multiple of this infusion rate. Oxime plasma concentrations were also measured. The organophosphorus agent was still detectable in some patients after several days or weeks. In the patients with ethyl and methyl several days or weeks. In the patients with ethyl and methyl parathion poisoning, enzyme reactivation could be obtained in some at oxime concentrations as low as 2.88 mg.l-1; in others, however, oxime concentrations as high as 14.6 mg.l-1 remained without effect. The therapeutic effect of the oxime seemed to depend on the plasma concentrations of ethyl and methyl parathion, enzyme reactivation being absent as long as these concentrations remained above 30 micrograms.l-1. The bromophos poisoning was rather mild, cholinesterases were moderately inhibited and increased under oxime therapy. The omethoate inhibited enzyme could not be reactivated.