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The application of analytical techniques for archaeometric investigation poses a major problem when dealing with objects of high values such as coins. Due to the unique character and rarity of some coins, any kind of analysis should be better non-destructive, which means that neither original sample material can be taken nor any kind of modification is allowed. Moreover, ancient Ag–Cu coins are usually affected by silver surface enrichment which extension in depth can reach several hundreds of microns, far beyond the penetration depth of surface techniques such as pXRF. In order to gain insight into the composition and microstructure of ancient coins, to establish their “real fineness” and to determine the reliability of data obtained with pXRF, the present paper presents, for the first time in literature, the results of the compositional and microstructural features of four medieval denari made of silver–copper alloy obtained by pXRF, SEM–EDX, and FTIR analyses. Three of them are some rare denari in the name of Berengario I minted in Pavia (898–900/902–915? AD) while the fourth coin is one denarius in the name of Henry IV-V minted in Lucca (1100–1130 AD). Results provided by SEM–EDX and FTIR analyses clearly demonstrate that archeological samples could be deeply heterogeneous due to both production techniques and corrosion phenomena. This poses a big question on the representativity of analytical data obtained only with non-destructive superficial methods or with those methods where only a few spot analyses were performed. However, the pXRF results provided a data set that, even if not particularly accurate, can clearly evidence, like for Berengario I coins, some completely unexpected heterogeneities, that represent without a doubt, a big interesting archaeometric anomaly. Despite the limited number of examples, it was possible to provide important data on two monetary types of difficult chronological collocation and attribution. [ABSTRACT FROM AUTHOR]

Tree barks are relevant interfaces between plants and the external environment, and can effectively retain airborne particles and elements at their surface. In this paper we have studied the distribution of mercury (Hg) in soils and in black pine ( Pinus nigra) barks from the Mt. Amiata Hg district in southern Tuscany (Italy), where past Hg mining and present-day geothermal power plants affect local atmospheric Hg concentration, posing serious environmental concerns. Barks collected in heavily Hg-polluted areas of the district display the highest Hg concentration ever reported in literature (8.6 mg/kg). In comparison, barks of the same species collected in local reference areas and near geothermal power plants show much lower (range 19–803 μg/kg) concentrations; even lower concentrations are observed at a “blank” site near the city of Florence (5–98 μg/kg). Results show a general decrease of Hg concentration from bark surface inwards, in accordance with a deposition of airborne Hg, with minor contribution from systemic uptake from soils. Preliminary results indicate that bark Hg concentrations are comparable with values reported for lichens in the same areas, suggesting that tree barks may represent an additional useful tool for biomonitoring of airborne Hg. [ABSTRACT FROM AUTHOR]

Abstract: Peptide nucleic acids (PNA) are very promising antisense agents, but their in vivo application is often hampered by their low bioavailability, mainly due to their limited uptake through cellular and nuclear membranes. However, PNA chemical synthesis easily allows modification with functional structures able to improve the intrinsically low permeability and great interest is arising in finding specific and efficient delivery protocols. Polymeric core-shell microspheres with anionic functional groups on the surface were tested for their ability to reversibly bind lysine modified PNA sequences, whose antisense activity against COX-2 mRNA was already demonstrated in murine macrophages. [Copyright &y& Elsevier]

Abstract: Peptide nucleic acids (PNAs) provide a powerful tool to study the mechanism of transcription and translation, an innovative strategy to regulate target gene expression. They have been successfully used in antisense technology, for their ability to specifically bind to messenger RNA (mRNA) targets and to inhibit translation of the target genes. However, unlike most of the DNA and RNA oligonucleotides, PNAs are poorly penetrated through the cell membrane, partially due to their uncharged property. To enhance the efficiency in PNA delivery, many strategies have been explored. We here compare the efficacy of three different delivery strategies for antisense PNA: 1) conjugation to hydrophobic peptides, 2) adsorption onto polymeric microspheres and 3) encapsulation in autologous erythrocytes. To this purpose, we designed and prepared PNA sequences able to inhibit the expression of macrophage enzymes involved in inflammatory process, i.e. nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) and tested their antisense activity in a murine macrophage cellular model. Both delivery through polymeric microspheres and encapsulation into erythrocytes allowed the antisense activity of unmodified PNAs at nanomolar concentration. [Copyright &y& Elsevier]

Examines the influence of peptide nucleic acids (PNA) in the inhibition of anti-inducible nitric oxide synthase. Delivery of PNA into macrophages; Pleiotropic activities of nitric oxide; Mechanisms of PNA-DNA hydrogen-bonded double helix formation.

Archaeological investigations of the Colline Metallifere district (Southern Tuscany, Italy) have highlighted several Medieval sites located close to the main Cu-Pb-Fe (Ag) ore occurrences. This study is focused on the investigation of late-medieval slags from Cugnano and Montieri sites using both geochemical and mineralogical methods to understand slag heterogeneities as result of ore differences and technological processes. Matte-rich slags present in both sites (with abundant matte ± speiss and frequent relict phases) represent waste products related to primary sulphide ore smelting to obtain a raw lead bullion. The distribution of slags between the Ca-rich or Fe-rich dominant composition, and the consequent mineralogy, are tracers of the different ore–gangue association that occurred in the two sites. Silver is present only in very small matte-rich slags and ores enclosed within the mortar of the Montieri site; wastes derived from silver-rich mineral charges were probably crushed for the recovery of silver. Matte-poor slags found at Montieri represent a second smelting; raw lead bullion obtained from matte slags (both Fe- and Ca-rich) was probably re-smelted, adding silica and Al2O3-phase-rich fluxes, under more oxidizing conditions to reduce metal impurities. This second step was probably employed for Zn-rich lead ores; this process helped to segregate zinc within slags and improve the quality of the metal. [ABSTRACT FROM AUTHOR]

Abstract Fluvial sediments of the Paglia River, a tributary of Tiber River (Central Italy), are contaminated by mercury (Hg) as a consequence of past mining activity (1846–1981, with main production 1900–1970) in the Monte Amiata district (the 3rd largest Hg producer worldwide). In this study, we combine a geomorphological analysis with geochemical data to try and understand the influence of fluvial dynamics on the spatial distribution of Hg in fluvial sediments over a 43 km segment of the river. By considering the evolution of the river course between 1883 and 2013, eight different geomorphic units (GUs) were recognised, including the active channel bed (baseflow channel and bar), the floodplain, and five orders of terraces. The distribution of Hg in sediments of these GUs reflects the timing of their formation with respect to evolution of the mining activity. In GUs formed before the main peak of mining activity, or after mine closure, sediments show mean Hg contents comparable to, or slightly higher than, the local background, estimated at 2–6 mg/kg; in GUs formed during the peak production, Hg mean contents are definitely higher (up to 26 mg/kg). The current floodplain also shows high contents (mean 19 mg/kg), because of continuous reworking and transport of older contaminated sediments during major flood events. Therefore, the point contaminant sources represented by mining centres evolved into a diffuse source spread over several tens of kilometres. By combining geochemical data with calculated sediment volumes, we estimate that not less than 63 tonnes of Hg are currently contained in the sediments of the investigated river stretch. Such amount of Hg will probably limit for the near future a full land use along the Paglia–Tiber course. Graphical abstract Unlabelled Image Highlights • The Paglia river catchment is affected by Hg released from the M. Amiata mining district. • Distribution of contaminants in river sediments is controlled by fluvial dynamics. • A total mass of 63 t Hg is accumulated in sediments of a 43 km-long river stretch. • This amount will pose limitations to land use in the affected area for the next decades. • Dispersion of contaminants in river sediments may change point sources into diffuse sources. [ABSTRACT FROM AUTHOR]

Fluid-rock interaction experiments between a biotite-rich schist (from Mt. Calamita Formation, Elba Island, Italy) and B-bearing aqueous fluids were carried out at 500-600 °C and 100-130 MPa. The experiments have been carried out in order to reproduce the reaction, which would have produced tourmalinisation of the biotite schist, supposedly by circulation of magmatic fluids issued from leucogranitic dykes. The reacting fluids were either NaCl-free or NaCl-bearing (20 wt %) aqueous solutions, with variable concentration of H3BO3 (0.01-3.2 M). The experimental results show that tourmaline (belonging to the alkali group) crystallise under high-temperature and upper crustal conditions (500-600 °C, 100-130 MPa) when H3BO3 concentration in the system is greater than 1.6 M. The composition of tourmaline is either dravitic (Mg-rich) or schorlitic (Fe-rich), depending if an NaCl-bearing or NaCl-free aqueous solution is used. In the first case, a significant amount of Fe released from biotite dissolution remains in the Cl-rich solution resulting from the experiment. By contrast, when pure water is used, Na/K exchange in feldspars makes Na available for tourmaline crystallisation. The high concentration of Fe in the residual fluid has an important metallogenic implication because it indicates that the interaction between the saline B-rich fluid of magmatic derivation and biotite-rich schists, besides producing tourmalinisation, is capable of mobilising significant amounts of Fe. This process could have produced, in part or totally, the Fe deposits located close to the quartz-tourmaline veins and metasomatic bodies of the Mt. Calamita Formation. Moreover, the super-hot reservoir that likely occurs in the deepest part of the Larderello-Travale geothermal field would also be the site of an extensive reaction between the B-rich fluid and biotite-bearing rocks producing tourmaline. Thus, tourmaline occurrence can be a useful guide during deep drilling toward a super-hot reservoir. [ABSTRACT FROM AUTHOR]

The SARS-CoV-2 life cycle is strictly dependent on the environmental redox state that influences both virus entry and replication. A reducing environment impairs the binding of the spike protein (S) to the angiotensin-converting enzyme 2 receptor (ACE2), while a highly oxidizing environment is thought to favor S interaction with ACE2. Moreover, SARS-CoV-2 interferes with redox homeostasis in infected cells to promote the oxidative folding of its own proteins. Here we demonstrate that synthetic low molecular weight (LMW) monothiol and dithiol compounds induce a redox switch in the S protein receptor binding domain (RBD) toward a more reduced state. Reactive cysteine residue profiling revealed that all the disulfides present in RBD are targets of the thiol compounds. The reduction of disulfides in RBD decreases the binding to ACE2 in a cell-free system as demonstrated by enzyme-linked immunosorbent and surface plasmon resonance (SPR) assays. Moreover, LMW thiols interfere with protein oxidative folding and the production of newly synthesized polypeptides in HEK293 cells expressing the S1 and RBD domain, respectively. Based on these results, we hypothesize that these thiol compounds impair both the binding of S protein to its cellular receptor during the early stage of viral infection, as well as viral protein folding/maturation and thus the formation of new viral mature particles. Indeed, all the tested molecules, although at different concentrations, efficiently inhibit both SARS-CoV-2 entry and replication in Vero E6 cells. LMW thiols may represent innovative anti-SARS-CoV-2 therapeutics acting directly on viral targets and indirectly by inhibiting cellular functions mandatory for viral replication. [ABSTRACT FROM AUTHOR]

Abstract: A significant As anomaly has been reported in the literature for stream sediments and unlithified Quaternary deposits of the Pecora River valley in Southern Tuscany, extending from the “Colline Metallifere” pyrite-base metals district to the Tyrrhenian Sea. The As anomaly spreads over several square kilometers around a core that exceeds 500ppm. Several source contributions (from natural to anthropogenic) have been invoked to explain the observed As distribution in the Pecora Valley, including the metal-working industry which was active in this area, particularly in Etrusco-Roman times and in the Middle Ages. In order to evaluate the contribution of ancient mining and metallurgical activities in the Pecora Valley to elevated As concentrations in the environment, a detailed mineralogical and geochemical survey of metallurgical slags and smelted ore minerals was undertaken from six different sites through the Pecora Valley: Poggio Butelli (Etrusco-Roman iron slags); Sata Creek, Arialla, Marsiliana, Forra and Cascata sites (all Medieval base metals slags). The As content of Etrusco-Roman slags is relatively low (few tens of ppm), whereas Medieval slags show variable, but higher amounts of base metals (±Ag) (ranging from tens to tens of thousands ppm) and As (up to 267ppm, with average contents of about 40ppm). Arsenic is mostly partitioned in sulfides disseminated through the glassy groundmass rather than in solid solution with the glassy matrix. Remnants of the ore used for base metal and Ag smelting during the Middle Ages had the highest As contents (up to about 1000ppm). The overall As concentration in the slags, independent of age and type, is generally lower than that found in stream sediments and Quaternary alluvial deposit outcrops of the upper Pecora Valley. Textural observations indicate that exogenous alteration of slags is minor and mostly confined to superficial exposures of matte droplets or along fractures; metal particles embedded within the glassy groundmass, even those located a few micrometres from the surface, appear to be unaltered. It is suggested, therefore, that As and contaminant metal contributions to the Pecora valley by archaeometallurgical slags was minor, at least for slags from the last 2500 to 700 a BP. Similarly, based on gross mass balance calculations, airborne release of As due to smelting/roasting operations in the past cannot account for the observed extent of the As anomaly in stream sediments and Quaternary deposits. Although residues of unsmelted (or partially smelted) Fe–Cu–Pb–Zn charges or fluxes for base metal metallurgy contain much greater amounts of As than smelting slags, their relatively low abundance would limit the overall input of As into the Pecora river valley. On the other hand, concurrent research seems to indicate a major “geogenic” contribution to the As anomaly in the Pecora Valley. [Copyright &y& Elsevier]

Bioreactivity and biocompatibility of a vitamin E-modified multi-layer hemodialysis filter. Background . The present study was designed to test the biocompatibility of a new vitamin E-modified multi-layer membrane (CL-E filter), as well as its ability to protect against oxygen free radicals during hemodialysis (HD). Methods. We investigated, both in vitro and in vivo , the bioreactivity of the filter with respect to the blood antioxidants and its ability to prevent lipoperoxidation. The effects on the leukocyte respiratory burst were also studied. Cuprammonium rayon was used as a comparison material (CL-S filter). Results. The in vitro results demonstrated that, under controlled conditions, CL-E is able to preserve blood antioxidants, and particularly vitamin E, from the spontaneous consumption observed in the incubation with CL-S filters and in control incubations. In accordance with this observation, the rate of the oxidative demolition of lipids either in plasma and red blood cells (RBC) or from rat brain homogenate decreased after the exposure to CL-E filters in comparison with the CL-S filter. Moreover, in the absence of any significant cytotoxic effects due to both the types of material studied, the production of oxygen free radicals and nitric oxide (NO) by leukocytes was higher after their in vitro exposure to CL-S, but was quite similar to that of the control leukocytes after exposure to CL-E. In vivo , a one-month treatment with the CL-E filter increased plasma vitamin E by 84.3% with respect to treatment with CL-S; this gain slightly decreased to 68.9% when CL-E treatment was prolonged to three months. In the RBC, vitamin E was found to have increased by 76.7% and 113.4% at one and three months, respectively. Plasma glutathione (GSH) levels determined at three months were significantly increased from 0.10 ± 0.02 to 0.33 ± 0.12 μmol/ml, while the erythrocyte GSH was only slightly increased. The leukocyte function estimated as... [ABSTRACT FROM AUTHOR]

Ceterach officinarum Willd is a plant widespread throughout Europe and used in southern Italy as a diuretic. Beliefs in the benefits of C. officinarum aqueous extract in the treatment of calcium oxalate kidney stones are widely held. Little is known, however, about the actual mechanism of its antilithiatic action. Our results in this in vitro study corroborate C. officinarum aqueous extract as a good source of antioxidants with a high antioxidant effects. Our results also demonstrate a major impact of C. officinarum aqueous extract on in vitro induced calcium oxalate crystallization kinetics and crystal morphology, showing its critical role in kidney stone formation and/or elimination. We show that progressively increasing doses of C. officinarum aqueous extract cause a sequence of effects. A powerful inhibitory action on calcium oxalate monohydrate (COM) growth and aggregation is first observed. C. officinarum aqueous extract also appears highly effective in stimulating nucleation increasing the number and reducing the size of COM crystals, which become progressively thinner, rounded and concave in a dose-dependent manner. These shape-modified COM crystals are known to be less adherent to renal tubular cells and more easily excreted through the urinary tract preventing kidney stone formation. Further, C. officinarum aqueous extract promotes the formation of calcium oxalate dihydrate (COD) rather than the monohydrate so that, at the highest concentrations used, only COD crystals are observed, in significant greater numbers with a clear reduction in their size, in a dose-dependent manner. Furthermore, AFM analyses allowed us to reveal the presence of C. officinarum component(s) on the surfaces of COD and modified COM crystals. The crystal surface adsorbed component(s) are shown to be similarly active as the total aqueous extract, suggesting a trigger factor which may direct crystal modification towards COD forms. In urolithiasis pathogenesis COD crystals are less dangerous than the COM forms due to their lower affinity for renal tubular cells. Our results are important in understanding the mechanisms which guide the modification induced by C. officinarum on the crystallization process. Based on these data, together with no adverse toxic effect being observed on the in vitro model of human intestinal enterocytes, C. officinarum aqueous extract could represent an attractive natural therapy for the treatment of urolithiasis. [ABSTRACT FROM AUTHOR]

Red stains are a common discolouration on stone cultural heritage all over the world. These are very difficult to remove and little is known about the reddish pigmentation. Numerous red stains were mapped on the Baptistery of San Giovanni in Florence, one of the most important monuments in Italy. This paper is focused on red stains on marble stone and the results of a detailed multidisciplinary approach are presented. Several analytical and investigation techniques (such as optical microscopy, X-ray fluorescence mapping, X-ray micro-tomography, micro-Raman spectroscopy, scanning electron microscopy with energy dispersive spectroscopy, microbial isolation, colorimetric measurements and isotopic analyses) were used to better understand the origin and processes involved in this kind of alteration. Analyses of the red stains led us to believe the presence of minium (lead tetroxide) and Pb are usually concentrated in the spaces between calcite grains. Red stains of Pb isotopic composition also overlap with data from Sardinian mines. These preliminary data seem to reinforce the suggestion of a source of lead from some metallic items (during restoration campaigns between 1938 and 1944, damaged parts were removed and replaced, and the new marble cladding was fixed with iron brackets treated with minium). [ABSTRACT FROM AUTHOR]

Coastal lagoons are subject to several sources of contaminations. To shade light on the contamination level of the Santa Gilla lagoon (Tyrrhenian Sea) we investigated the spatial distribution of Cr, Ni, Pb, Zn and Hg in sediments and their correlation with grain size and organic matter contents. Moreover, sediment contamination levels and the ecological risk associated with metal concentration were assessed using different abiotic indicators. The lagoon is characterised by low levels of contamination, with exceptions for Pb and Hg, whose distribution reflects the position of an old chlor-alkali plant and that of an airport. These results indicate that the restoration put in place 30 years ago have not reached the expected target and that the presence of the airport deserves further attention. In the outer section of the lagoon, where clam fishery occurs, we observed low levels of contamination suggesting that such artisanal fishery could somehow help mobilising metals. We conclude that the area exposed to Hg pollution, though tentatively restored, still suffers of a potential risk of ecosystem deterioration. We pinpoint that further investigations on the mobility, bioavailability and toxicity of metals are needed to finally address the actual impairment of the Santa Gilla lagoon. [ABSTRACT FROM AUTHOR]

Iron exopolysaccharide nanoparticles were biogenerated during ferric citrate fermentation by Klebsiella oxytoca DSM 29614. Before investigating their effects on Tuber borchii ('bianchetto' truffle) mycelium growth and morphology, they were tested on human K562 cell line and Lentinula edodes pure culture and shown to be non-toxic. Using these nanoparticles as iron supplement, the truffles showed extremely efficient iron uptake of over 300 times that of a commercial product. This avoided morphological changes in T. borchii due to lack of iron during growth and, with optimum nanoparticle dosage, increased growth without cell wall disruption or alteration of protoplasmatic hyphal content, the nuclei, mitochondria, and rough endoplasmic reticula being preserved. No significant modifications in gene expression were observed. These advantages derive from the completely different mechanism of iron delivery to mycelia compared to commercial iron supplements. The present data, in fact, show the nanoparticles attached to the cell wall, then penetrating it non-destructively without damage to cell membrane, mitochondria, chromatin, or ribosome. Low dosage significantly improved mycelium growth, without affecting hyphal morphology. Increases in hyphal diameter and septal distance indicated a healthier state of the mycelia compared to those grown in the absence of iron or with a commercial iron supplement. These positive effects were confirmed by measuring fungal biomass as mycelium dry weight, total protein, and ergosterol content. This 'green' method for biogenerating iron exopolysaccharide nanoparticles offers many advantages, including significant economic savings, without toxic effects on the ectomycorrhizal fungus, opening the possibility of using them as iron supplements in truffle plantations. [ABSTRACT FROM AUTHOR]

Dolia are large pottery containers used in Roman times for the storage and fermentation of wine. They were produced in specialized pottery workshops ( figlinae) and were typically marked with specific epigraphical stamps, which represent a major tool to unravel their provenance and trade. In this work we present the preliminary results of a study of two dolia defossa, recently found at San Giovanni (Portoferraio, island of Elba, Italy) during 2012-2014 archaeological excavations in a Roman farm (late 2nd cent. BC-1st cent. AD), devoted to wine production and probably constituting the antecedent archaeological phase of the adjacent 'Villa delle Grotte'. Based on archaeological (epigraphic) evidence, five different production areas have been hypothesized: 1) Elba island, where the dolia have been found; 2) the municipal figlinae in the Pisa territory; 3) the middle catchment of the Tiber river (central Latium) where 'urban' figlinae occurred; 4) the figlinae of Minturno (southern Latium), a locality known both for wine production and exportation and for the presence of ancient figlinae; 5) the municipal figlinae in the Volterra territory. Archaeometric analysis of tempering agents intentionally added to the clay for the manufacturing of the dolia, particularly magmatic lithic fragments and clinopyroxene crystals, allowed us to suggest that the watershed of the central Tiber Valley - including different volcanic centres belonging to both Tuscany Magmatic Province (Monti Cimini) and Roman Magmatic Province (Monti Vulsini and Vico volcano) - could have been the most likely sites of production of the dolia found at San Giovanni. Alternatively, the site of Minturno (southern Latium) could be proposed. [ABSTRACT FROM AUTHOR]

Injection of the LP-BM5 murine leukemia virus into mice causes murine AIDS, a disease characterized by many dysfunctions of immunocompetent cells. To establish whether the disease is characterized by glutathione imbalance, reduced glutathione (GSH) and cysteine were quantified in different organs. A marked redox imbalance, consisting of GSH and/or cysteine depletion, was found in the lymphoid organs, such as the spleen and lymph nodes. Moreover, a significant decrease in cysteine and GSH levels in the pancreas and brain, respectively, was measured at 5 weeks postinfection. The Th2 immune response was predominant at all times investigated, as revealed by the expression of Th1/Th2 cytokines. Furthermore, investigation of the activation status of peritoneal macrophages showed that the expression of genetic markers of alternative activation, namely, Fizz1, Ym1, and Arginase1, was induced. Conversely, expression of inducible nitric oxide synthase, a marker of classical activation of macrophages, was detected only when Th1 cytokines were expressed at high levels. In vitro studies revealed that during the very early phases of infection, GSH depletion and the downregulation of interleukin-12 (IL-12) p40 mRNA were correlated with the dose of LP-BM5 used to infect the macrophages. Treatment of LP-BM5-infected mice with N-(N-acetyl-L-cysteinyl)-S-acetylcysteamine (I-152), an N-acetyl-cysteine supplier, restored GSH/cysteine levels in the organs, reduced the expression of alternatively activated macrophage markers, and increased the level of gamma interferon production, while it decreased the levels of Th2 cytokines, such as IL-4 and IL-5. Our findings thus establish a link between GSH deficiency and Th1/Th2 disequilibrium in LP-BM5 infection and indicate that I-152 can be used to restore the GSH level and a balanced Th1/Th2 response in infected mice. [ABSTRACT FROM AUTHOR]

The Mount Amiata mining district (southern Tuscany, Italy) was, for decades, one of the world's largest mercury (Hg) producing regions, where mining activity lasted until the 1980s. The Paglia River drains the eastern part of the district and is also the main western tributary of the Tiber River. Recent studies show that, still today, high total Hg contents severely affect the downstream ecosystems of these rivers. In November 2012, a major flood event occurred in the Paglia River basin, which drastically changed the river morphology and, possibly, the Hg concentrations. In the present work, stream sediment was sampled before and after the flood to evaluate possible changes in sediment total Hg concentrations as a consequence of this event. The comparison between pre- and post-flood Hg concentrations shows that Hg content increased up to an order of magnitude after the flood, suggesting that this event triggered Hg mobilization in the basin rather than its dilution. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to develop and characterize new nanoparticle systems based on Eudragit RS 100 and cyclodextrins (CDs) for the transmucosal administration of glutathione (GSH). For this purpose, nanoparticles (NPs) with the mucoadhesive properties of Eudragit RS 100 and the penetration enhancing and peptide protective properties of CDs were prepared and evaluated. The quasi-emulsion solvent diffusion technique was used to prepare the NPs with natural and chemically modified (HP-β-CD and Me-β-CD) CDs. The NPs prepared showed homogeneous size distribution, mean diameters between 99 and 156nm, a positive net charge and spherical morphology. Solid state FT-IR, thermal analysis (DSC), and X-ray diffraction studies suggest that the nanoencapsulation process produces a marked decrease in crystallinity of GSH. The encapsulation efficiency of the peptide was found to be between 14.8% and 24%. The results indicate that mean diameters, surface charges and drug-loaded NPs were not markedly affected by the CD, whereas the presence of the latter influences drug release and to some extent peptide stability and absorption. Finally, it has been shown that CD/Eudragit RS 100 NPs may be used for transmucosal absorption of GSH without any cytotoxicity using the epithelial human HaCaT and murine monocyte macrophage RAW264.7 cell lines. [Copyright &y& Elsevier]

Two novel classes of biocompatible core-shell anionic microspheres, composed of an inner hard insoluble core, either made of poly(styrene) (PS) or poly(methyl methacrylate) (PMMA), and a soft outer tentacular shell made of long soluble negatively charged arms derived from the steric stabilizer, hemisuccinated poly(vinyl alcohol) or Eudragit L100/55, respectively, were prepared by dispersion polymerization and characterized. Five types of these novel microspheres, two made of poly(styrene) and hemisuccinated poly(vinyl alcohol) (A4 and A7), and three made of poly(methyl methacrylate) and Eudragit L100/55 (1D, 1E, H1D), differing for chemical composition, size, and surface charge density were analyzed for the delivery of the HIV-1 Tat protein for vaccine applications. All microspheres reversibly adsorbed the native biologically active HIV-1 Tat protein preventing Tat from oxidation and maintaining its biological activity, therefore increasing the shelf-life of the Tat protein vaccine. The microspheres efficiently delivered Tat intracellularly, and were not toxic in vitro nor in mice, even after multiple administrations. These results indicate that these novel microparticles are safe and represent a promising delivery system for vaccination with Tat, as well as for other subunit vaccines, particularly when a native protein conformation is required. [Copyright &y& Elsevier]

A new combined solid-liquid phase synthesis method for a spin labeled peptide nucleic acid (PNA) is developed. The methodology involved initial preparation of a protected PNA on solid phase, followed by efficient solution phase coupling to a spin label containing a reactive carboxylic group. This strategy allows to maintain the integrity of the nitroxide moiety during the various steps of chemical synthesis assuring in the same time the fidelity of the hybridization assay. This compound can be used as a reporter molecule to investigate the binding of peptide nucleic acids to oligonucleotide sequences (DNA or RNA) by EPR spectroscopy. [Copyright &y& Elsevier]

The results of the combined use of Fludarabine, an anticancer agent that may be able to target latently infected cells, and conventional antiretroviral therapy (AZT+DDI) in a murine model of AIDS, i.e., LP-BM5 infection, are reported. Eighty percent of infected mice, treated with four cycles of alternate administration of Fludarabine and AZT+DDI, showed undetectable levels of proviral DNA in lymph nodes. After 8 weeks of treatment interruption, the infected/treated animals, although still alive at a time when all untreated animals had succumbed to the infection, showed disease progression and reappearance of proviral DNA in lymph nodes. The retrospective analysis of proviral DNA content in spleen and bone marrow at the end of the fourth cycle of treatment revealed a low but detectable amount of BM5d proviral DNA. We thus concluded that the spleen and bone marrow may be less sensitive to lympholitic drugs and therefore act as viral reservoirs in LP-BM5 infection. This study suggests that optimized protocols of alternate administration of cytolytic and antiretroviral drugs may represent a useful strategy to eradicate retroviral infections. [Copyright &y& Elsevier]

• Pinus nigra barks are good biomonitoring substrata for airborne Hg. • Tree bark concentration for Hg may be influenced by sampling methodology. • Sampling can be conveniently done at 150 cm height from the soil on the outer 1.5 cm. • Sampling orientation with respect to wind directions does not affect Hg in barks. • Negligible Hg is lost from bark tissues during leaching tests. Tree barks are increasingly used as biomonitors of airborne pollutants. However, many authors stress the poor comparability of the results achieved in different studies. This drawback is mainly caused by a poor understanding of the critical sampling parameters to be considered. To minimize the biases that could be introduced during sampling, in this study the barks of Pinus nigra J.F. Arnold from thirteen sites were investigated in the abandoned Mt. Amiata mercury (Hg) mining district (Southern Tuscany, Italy) and surroundings. The influence of some sampling and analyzing parameters on Hg content was critically assessed. At each site, a total of eight bark samples were taken from a single tree at two heights (70 cm and 150 cm from soil) and at four different sides of the trunk, corresponding to the four cardinal directions; a composite soil sample was also collected. Mercury contents in barks range from 0.1 to 28.8 mg/kg, and are correlated with soil Hg contents (1–480 mg/kg), indicating that barks record both gaseous Hg concentrations in air, and wind-transported Hg-bearing particulate. For each tree, samples at 70 cm and 150 cm show Hg contents of the same order of magnitude, even if values for 150 cm are slightly less dispersed, possibly because barks at 70 cm are more influenced by random soil particles. There is no statistically significant dependence of Hg content on direction and tree age. Simulated rain events cause a negligible loss of Hg from barks. Results suggest that a convenient sampling practice for Pinus nigra is to collect a bark slice (typically 1–2 mm) within the outermost 1.5 cm layer. [ABSTRACT FROM AUTHOR]