Exposure to urban pollutants and serum levels of IgG anti Herpes Simplex virus type 1

The aim of the study is to investigate whether traffic policemen exposed to urban pollutants and psycho-social stressors may be at risk of modifications in serum levels of immunoglobulins G antibodies (IgG Ab) against Herpes Simplex Virus (type1) (HSV-1) compared with controls. Traffic policemen were matched by sex, age, working life and drinking habits (less than two glasses of wine or beer per day) with controls, after excluding the subjects with the principal confounding factors (smoking habit, use of paints, solvents, pesticides and drinking habits). Were included in the study 125 traffic policemen (54 men and 71 women) with outdoor activity and 125 controls (54 men and 71 women) with indoor activity. Mean levels of IgG Ab against HSV-1 were significantly higher in traffic policemen of both sexes compared with controls. The frequency of workers with IgG Ab against HSV-1 levels higher than our normal laboratory values, was significant in traffic policemen compared with controls of both sexes. The distributions of IgG Ab against HSV-1 levels in traffic policemen compared with controls of both sexes were significant. The authors hypothesise an effect of the working activity in traffic policemen on serum levels of IgG Ab against HSV-1 compared to controls.     

A field method for sampling toluene in end-exhaled air, as a biomarker of occupational exposure: correlation with other exposure indices

A sensitive and rapid method for the determination of toluene in exhaled air is described. We have developed a device for direct breath sampling consisting of a sampler inserted into an empty 58 mL glass vial closed by a Teflon rubber septum. The sorbent cartridge functions as a diffusive sampler and employs a Tenax resin (300 mg, 35/50 mesh) to trap volatile organic compounds from the exhaled air. End-exhaled air is collected "in field" by removing the septum from the vial, by forcibly exhaling into the device through a suitable Teflon tube, and then by sealing the bottle quickly. Environmental toluene levels ranged from 13 to 191 mg/m3, while the concentrations of the solvent in alveolar air, in blood and urine ranged from 159 to 3354 ng/L, from 3.6 to 53.5 microg/L, and from 8.7 to 142.4 microg/L respectively. The correlation coefficients (r) of biological measurements towards environmental toluene levels were 0.822, 0.850 and 0.846 for alveolar air, blood and urine samples, respectively. The breath sampler allowed the rapid and non-invasive collection of data on elimination of toluene.     

Calcium ionophoretic and apoptotic effects of ferutinin in the human Jurkat T-cell line

We have investigated the ionophoretic and apoptotic properties of the daucane sesquiterpene ferutinin and three related compounds, ferutidin, 2-alpha-hydroxyferutidin and teferin, all isolated from various species of plants from the genus Ferula. Ferutinin induced a biphasic elevation of intracellular Ca2+ in the leukemia T-cell line, Jurkat. First, a rapid calcium peak was observed and inhibited by BAPTA-AM. This initial calcium mobilization was followed by a sustained elevation, mediated by the entry of extracellular calcium through L-type calcium channels and sensitive to inhibition by EGTA. Moreover, ferutinin-induced apoptosis in Jurkat cells, and this event was preceded, in a cyclosporine-A sensitive manner, by a loss of mitochondrial transmembrane potential (DeltaPsim) and by an increase in intracellular reactive oxygen species. Ferutinin-induced DNA fragmentation was mediated by a caspase-3-dependent pathway, and was initiated independently of any specific phase of the cell cycle. The evaluation of ferutinin analogs in calcium mobilization and apoptosis assays showed strict structure-activity relationships, with p-hydroxylation of the benzoyl moiety being requested for activity.     

Effects of GW274150, a novel and selective inhibitor of iNOS activity, in acute lung inflammation

1. The aim of this study was to investigate the effect of GW274150, a novel, potent and selective inhibitor of inducible nitric oxide synthase (iNOS) activity in a model of lung injury induced by carrageenan administration in the rats. 2. Injection of carrageenan into the pleural cavity of rats elicited an acute inflammatory response characterized by: fluid accumulation in the pleural cavity which contained a large number of polymorphonuclear cells (PMNs) as well as an infiltration of PMNs in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NO(x)), tumour necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta). 3. All parameters of inflammation were attenuated in a dose-dependent manner by GW274150 (2.5, 5 and 10 mg x kg(-1) injected i.p. 5 min before carrageenan). 4. Carrageenan induced an upregulation of the intracellular adhesion molecules-1 (ICAM-1), as well as nitrotyrosine and poly (ADP-ribose) (PAR) as determined by immunohistochemical analysis of lung tissues. 5. The degree of staining for the ICAM-1, nitrotyrosine and PAR was reduced by GW274150. These results clearly confirm that NO from iNOS plays a role in the development of the inflammatory response by altering key components of the inflammatory cascade. 6. GW274150 may offer a novel therapeutic approach for the management of various inflammatory diseases where NO and related radicals have been postulated to play a role.     

The N-terminal of icatibant and bradykinin interact with the same Asp residues in the human B2 receptor

The pharmacology of peptide and non-peptide bradykinin B2 receptor ligands was evaluated in the inositol phosphate (IP) production assay in CHO cells expressing the human bradykinin B2 receptor. The effect of single and double alanine mutation of D266 and D284 residues at the human bradykinin B2 receptor was evaluated on the agonist profile of bradykinin (H-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-OH) and the synthetic agonist FR190997 (8-[2,6-dichloro-3-[N-methylcarbamoyl)cinnamidoacetyl]-N-methylamino]benzyloxy]-2-methyl-4-(2-pyridylmethoxy)quinoline). Bradykinin potency (EC50 0.5 nM at the wild-type receptor) was reduced by 16-fold at D266A and D284A mutants and by 2300-fold at the D266A/D284A double mutant. None of the mutants affected the potency or the efficacy of FR190997. Peptide antagonists, Icatibant (H-DArg-Arg-Pro-Hyp-Gly-Thi-Ser-Dtic-Oic-Arg-OH) and MEN11270 (H-DArg-Arg-Pro-Hyp-Gly-Thi-c(Dab-DTic-Oic-Arg)c(7gamma-10alpha)) (100 nM) similarly antagonized the concentration-response curve to bradykinin or FR190997 (pA2 values 8.5 and 8.4 versus bradykinin and 8.2 and 8.4 versus FR190997) at the wild-type receptor. Non-peptide antagonists FR173657 ((E)-3-(6-acetamido-3-pyridyl)-N-[N-[2,4-dichloro-3-[(2-methyl-8-quinolinyl) oxymethyl]phenyl]-N-methylaminocarbonyl methyl]acrylamide) and LF16-0687 (1-[[2,4-dichloro-3-[(2,4-dimethylquinolin-8-yl)oxy] methyl]-phenyl]sulfonyl]-N-[3-[[4-(aminoiminomethyl)-phenyl]carbonylamino]propyl]-(S)-pyrrolidine carboxamide) (100 nM) showed an equivalent potency values in blocking the IP production induced by bradykinin or FR190997 (pA2 values 8.7 and 8.8 versus bradykinin and 8.8 and 8.6 versus FR190997). Whilst the antagonist potency of FR173657 and LF16-0687 was not affected by D266A/D284A double mutation (IP production induced by the synthetic agonist), that of Icatibant and MEN11270 was reduced by 50- and 200-fold. The antagonist potency of [Ala1]-Icatibant and [Ala2]-Icatibant (pA2 values at wild-type 7.7 and 6.4) was significantly less reduced (20-fold and 13-fold, respectively) by the D266A/D284A double mutation. Our results highlight a crucial role for two aspartic residues, D266 and D284, located at the top of transmembrane segments 6 and 7, in the high-affinity interaction of peptide antagonists with the human bradykinin B2 receptor. An interaction of these receptor residues with the N-terminal basic residues of Icatibant is hypothesized.     

Novel synthesis of 3,4-diarylisoxazole analogues of valdecoxib: reversal cyclooxygenase-2 selectivity by sulfonamide group removal

3,4-Diarylisoxazole analogues of valdecoxib [4-(5-methyl-3-phenylisoxazol-4-yl)-benzensulfonamide], a selective cyclooxygenase-2 (COX-2) inhibitor, were synthesized by 1,3-dipolar cycloaddition of arylnitrile oxides to the enolate ion of phenylacetone regioselectively prepared in situ with lithium diisopropylamide at 0 degrees C. The corresponding 3-aryl-5-methyl-4-phenylisoxazoles were easily generated by a dehydration/aromatization reaction under basic conditions of 3-aryl-5-hydroxy-5-methyl-4-phenyl-2-isoxazolines and further transformed into their benzenesulfonamide derivatives. The biochemical COX-1/COX-2 selectivity was evaluated in vitro by using the human whole blood assays of COX isozyme activity. Three compounds not bearing the sulfonamide group present in valdecoxib were selective COX-1 inhibitors.     

Dissociation of [3H]L-glutamate uptake from L-glutamate-induced [3H]D-aspartate release by 3-hydroxy-4,5,6,6a-tetrahydro-3aH-pyrrolo[3,4-d]isoxazole-4-carboxylic acid and 3-hydroxy-4,5,6,6a-tetrahydro-3aH-pyrrolo[3,4-d]isoxazole-6-carboxylic acid, two conformationally constrained aspartate and glutamate analogs

We characterized the interaction of two conformationally constrained aspartate and glutamate analogs, 3-hydroxy-4,5,6,6a-tetrahydro-3aH-pyrrolo[3,4-d]isoxazole-4-carboxylic acid (HIP-A) and 3-hydroxy-4,5,6,6a-tetrahydro-3aH-pyrrolo[3,4-d]isoxazole-6-carboxylic acid (HIP-B), with excitatory amino acid transporters (EAATs) in rat brain cortex synaptosomes. HIP-A and HIP-B were potent and noncompetitive inhibitors of [(3)H]L-glutamate uptake, with IC(50) values (17-18 microM) very similar to that of the potent EAAT inhibitor dl-threo-beta-benzyloxyaspartic acid (TBOA). The two compounds had little effect in inducing [(3)H]D-aspartate release from superfused synaptosomes but they potently inhibited l-glutamate-induced [(3)H]D-aspartate release, thus behaving as EAAT blockers, not substrates, in a manner similar to those of TBOA and dihydrokainate (DHK). HIP-A and HIP-B, but not TBOA and DHK, unexpectedly inhibited L-glutamate-induced [(3)H]D-aspartate release with IC(50) values (1.2-1.6 microM) 10 times lower than those required to inhibit [(3)H]L-glutamate uptake. There is therefore a concentration window (1-3 microM) in which the two compounds significantly inhibited l-glutamate-induced release with very little effect on L-glutamate uptake. This selective inhibitory effect required quite long preincubation (>5 min) of synaptosomes with the drugs. At these low concentrations, however, HIP-A and HIP-B had no effect on the EAAT-mediated [(3)H]d-aspartate release induced by altering the ion gradients, indicating that they specifically affect some L-glutamate-triggered process(es)--different from L-glutamate translocation itself--responsible for the induction of reverse transport. These data are inconsistent with the classic model of facilitated exchange-diffusion and provide the first evidence that EAAT-mediated substrate uptake and substrate-induced EAAT-mediated reverse transport are independent. Compounds such as HIP-A and HIP-B could be useful to further clarify the mechanisms underlying these operating modes of transporters.     

EEG power spectra and auditory P300 during free smoking and enforced smoking abstinence

We investigated resting EEG and auditory P300 during free smoking and 36 h of enforced smoking abstinence in 12 healthy volunteers. Resting EEG was recorded on 19 scalp leads and auditory P300 was obtained by an oddball paradigm task. Spectral analysis of EEG (absolute and relative power, mean frequency), latency and amplitude of auditory P300 were considered for statistical analysis. EEG changes were not significant during free smoking but were significant during smoking abstinence. Theta absolute power increased by +57% (P<.001), whereas alpha and delta absolute power increased by +26% (P<.01) and +19% (P<.01), respectively; theta absolute power change was delayed and prolonged. Alpha mean frequency reduced by -0.31 Hz (P<.001), whereas delta, theta and beta1 mean frequency increased by +0.13 Hz (P<.05), +0.09 Hz (P<.05) and +0.23 Hz (P<.01), respectively. Auditory P300 amplitude and latency were unaffected by smoking abstinence. Resting EEG, but not auditory P300, was sufficiently sensitive to detect changes during enforced smoking abstinence, and EEG bands had different temporal changes.     

Blood lead levels, clinico-pathological findings and erythrocyte metabolism in dogs from different habitats

Biological markers of lead exposure were measured in 20 dogs from five different habitats chosen on the basis of the degree of anthropogenic influence. None of the dogs had clinical signs of lead poisoning. Compared to controls, blood lead concentrations were significantly higher in dogs from industrial areas, confirming the role of lead emissions in environmental pollution and the possible role of dogs as biomonitors of lead exposure in these areas. Whole blood lead concentrations were similar in dogs living in urban and rural areas, probably due to "indirect" lead sources and due to decreased urban lead contamination. As in humans, individual variability was detected. No significant correlation between clinico-pathological changes (hematology, clinical chemistry, Delta-aminolevulinic acid dehydratase activity and other intra-erythrocytic metabolic parameters) and lead concentration were observed. Our findings suggest dogs can be useful as sentinels of environmental lead exposure.     

Rivastigmine in vascular dementia

Patients with vascular dementia (VaD) show cholinergic deficits that may result in characteristic clinical syndromes for different subtypes of the condition. Subcortical VaD is characterised by executive dysfunction and behavioural problems, reflecting deterioration of the frontal lobe. Based on limited open-labelled controlled studies of rivastigmine in VaD, this article aims to determine whether rivastigmine, a dual inhibitor of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), has any effects on the typical symptoms of subcortical VaD. Long-term rivastigmine treatment is safe and effective. Improvements in domains that characterise subcortical VaD were observed, indicating that rivastigmine may have provided targeted treatment in areas of the brain that are particularly affected in this patient population. A large, double-blind study of rivastigmine in patients with VaD is clearly warranted.