RAFT "grafting-through" approach to surface-anchored polymers: Electrodeposition of an electroactive methacrylate monomer.

The synthesis of homopolymer and diblock copolymers on surfaces was demonstrated using electrodeposition of a methacrylate-functionalized carbazole dendron and subsequent reversible addition-fragmentation chain transfer (RAFT) "grafting-through" polymerization. First, the anodically electroactive carbazole dendron with methacrylate moiety (G1CzMA) was electrodeposited over a conducting surface (i.e. gold or indium tin oxide (ITO)) using cyclic voltammetry (CV). The electrodeposition process formed a crosslinked layer of carbazole units bearing exposed methacrylate moieties. This film was then used as the surface for RAFT polymerization process of methyl methacrylate (MMA), styrene (S), and tert-butyl acrylate (TBA) in the presence of a free RAFT agent and a free radical initiator, resulting in grafted polymer chains. The molecular weights and the polydispersity indices (PDI) of the sacrificial polymers were determined by gel permeation chromatography (GPC). The stages of surface modification were investigated using X-ray photoelectron spectroscopy (XPS), ellipsometry, and atomic force microscopy (AFM) to confirm the surface composition, thickness, and film morphology, respectively. UV-Vis spectroscopy also confirmed the formation of an electro-optically active crosslinked carbazole film with a [Formula: see text] - [Formula: see text] absorption band from 450-650nm. Static water contact angle measurements confirmed the changes in surface energy of the ultrathin films with each modification step. The controlled polymer growth from the conducting polymer-modified surface suggests the viability of combining electrodeposition and grafting-through approach to form functional polymer ultrathin films.

[Organizational and management companies models]. / Modelli di organizzazione e gestione aziendale.

With the legislative decree 81/08 and s.m.i. it's explicitly defined a model of management and corporate organization that can contribute to prevent security risks in work environments. The realization of the model is not obligatory, but desirable because the result of its implementation is a decrease of company's risks and costs for safety. Our study group has developed the structure of an organizational and management model for corporate safety and the tools necessary for its realization. The realization of a model is structured in various phases: initial exam, safety policy, planification, implementation, monitoring, system retest and improvement. Such a model, in continuous evolution, is based on the responsibilities of the different corporate figures through an accurate analysis of the measured risks and the measures adopted.

[Meta-analysis: effectiveness of the preventive interventions in agriculture accidents]. / Meta-analisi: efficacia degli interventi preventivi negli infortuni in agricoltura.

The aim of our study is to determine the effectiveness in reducing workplace accidents in agriculture using preventive interventions including awareness and effective knowledge of hazards with workers who followed training-informative programs. On the basis of the data reported in the 11 studies three categories we identified: Reduction in the number of workplace accidents: comparison between groups; Reduction in the number of workplace accidents: before-after comparison; Self-rating of injuries risk reduction. The second category showed significant statistical differences in the subgroup who followed preventive intervention compared to subgroup who did not follow this intervention. The third category showed a significant statistical increase of the Consciousness Index of the agricultural workers who followed the training-informative programs. The results suggested the need to use assessment models more suitable to the nature of the examined variables. A promising area is the evaluation of knowledge of risks achieved by workers exposed to formative-informative programs.

Follicle-stimulating hormone levels in male workers exposed to urban chemical, physical, and psychosocial stressors.

The aim of this study is to evaluate whether occupational exposure to urban stressors could cause alterations in the follicle-stimulating hormone (FSH) levels in traffic policemen compared to a control group. After excluding the subjects with main confounding factors, traffic policemen and male controls were matched by age, working life, body mass index (BMI), drinking habit, cigarette smoking history, and daily consumption of Italian coffee, 166 traffic policemen and 166 controls were included into the study. FSH levels were significantly higher in traffic policemen compared to male controls (P < 0.05). The distribution of FSH values in traffic policemen and controls was significant (P < 0.05). Our results suggest that occupational exposure to low doses of chemical and psychosocial stressors may alter plasma levels of FSH in traffic policemen more than in the control group. If the results obtained are confirmed by further research, the plasma levels of FSH may be used as early biological markers, valuable for the group, used in occupational set even before the appearance of disorders of male fertility.

Pharmacokinetics of nerve growth factor (NGF) following different routes of administration to adult rats.

The suggested potential for therapeutic use of nerve growth factor (NGF) in the treatment of toxic and degenerative disorders of the nervous system indicates a need to determine its pharmacokinetics. To this end, murine NGF was administered to adult rats and multiple blood samples were withdrawn at intervals. NGF levels, determined in plasma samples by a two-site enzyme immunoassay, were used to determine the pharmacokinetics of NGF. These studies demonstrate that murine NGF has a distribution half-life of about 5.4 min and an elimination half-life of 2.3 h following intravenous injection. When administered by subcutaneous (sc) injection, the elimination half-life is prolonged to 4.5 h. Administration of NGF by sc continuous infusion, using mini-osmotic pumps, provides stable, dose-related levels of circulating NGF within few days from pump implantation. Upon removal of the pump, NGF levels show a rapid decay (t1/2 about 1.5 h) followed by a slow elimination phase (t1/2 about 150 h). These pharmacokinetic parameters might serve for selection of an appropriate administration route and dose regimen that would optimize schedule-dependent expression of NGF therapeutic activity.

Nerve growth factor modulates the expression of muscarinic cholinergic receptor messenger RNA in telencephalic neuronal cultures from newborn rat brain.

The effect of nerve growth factor (NGF) on muscarinic receptor subtypes was investigated in a primary culture of telencephalic neurons prepared from neonatal rats. The treatment with 100 ng/ml of NGF significantly enhanced choline acetyltransferase (ChAT) activity and intracellular acetylcholine (ACh) content during cultivation. The same treatment induced an early transient increase of the number of muscarinic cholinergic receptors (mAChR), as measured by [3H]quinuclidinyl benzilate binding to cell homogenate, that was followed by a dramatic decrease of the receptor density from the 9th day of culture. Atropine completely prevented the decrease of the maximal number of muscarinic recognition sites induced by NGF. Prolonged exposure of telencephalic neurons to NGF also induced a significant reduction of the relative content of the messenger RNA (mRNA) encoding m1 and m3 receptors, while the m4 transcript was increased by the treatment. We suggest that the prolonged stimulation of cholinergic neurons by NGF induces a downregulation of m1 and m3 mAChR and their mRNAs on the postsynaptic site, while it increases the synthesis of the functionally distinct m4 receptor subtype, which might be presynaptically localized on cholinergic neurons. The transient increase of the receptor number that occurs at the first days of culture was not paralleled by changes in the relative content of mAChR mRNAs and might be associated with the trophic activity of NGF on cholinergic synapses during early development.

Choline acetyltransferase activity in murine thymus.

Murine thymus has been demonstrated to contain both cholinergic receptors and acetylcholinesterase activity. In the present study we have investigated the presence of the enzyme choline acetyltransferase in this organ, which is responsible for the synthesis of acetylcholine. Results reported here demonstrate that (1) an appreciable amount of the enzyme is already present in the thymus on the day of birth; (2) its expression is developmentally regulated; and (3) thymic atrophy, induced in young (2-week-old) and adult (6-week-old) mice by i.p. injection of hydrocortisone for 2 days, is accompanied by significant reduction of choline acetyltransferase activity only in young mice. Altogether these results demonstrate the presence in the murine thymus of functionally relevant markers of the cholinergic system that might interface the interactions between the nervous and immune systems.

[Brucellosis]. / Le brucellosi.

Brucellosis is as yet an unsolved problem in view of its persistent occurrence in spite of government-sponsored prophylactic campaigns in animals. Environmental, social, economic and behavioral factors prevent the eradication of brucellosis from our country. The authors report epidemiological data of animal and human brucellosis during the last ten years, and stress the need for the vaccination of animals, hoping for an increased sensitivity among breeders and for a more efficient and consequent control by the responsible health authorities, as well as for appropriate and comprehensive control of foodstuffs, above all of milk and milk products.

Cholinergic agonists selectively induce proliferative responses in the mature subpopulation of murine thymocytes.

The incubation of murine thymocytes for 24 hr in the presence of cholinergic agonists induces selective proliferation of PNA- cells as measured by thymidine incorporation. The response of PNA- cells is mediated by the activation of nicotinic receptors. This conclusion is suggested by the inability of the muscarinic agonist, oxotremorine, to induce cell proliferation and by the inhibition exerted by the nicotinic antagonist, d-tubocurarine. The presence of cholinergic axons in the murine thymus adds biological interest to the selective expression of functional cholinergic receptors on mature thymocytes.