RESUMO
This study stems from the need for numismatics to establish whether there may be relationships between a group of 103 bronze coins from the Roman era found in archaeological excavations on the Cesén Mountain (Treviso, Italy) and a group of 117 coins kept at the Museum of Natural History and Archaeology in Montebelluna (Treviso, Italy). The chemists were delivered six coins with neither pre-agreements nor further information on the origin of the coins. Therefore, the request was to hypothetically assign the coins to the two groups on the basis of similarities and differences in their surface composition. Only non-destructive analytical techniques were allowed to be used to characterize the surface of the six coins taken blindly from the two sets. The elemental analysis of each coins' surface was carried out by µ-XRF. To better observe the morphology of the coins' surfaces, SEM-EDS was used. Compounds covering the coins coming from both corrosion processes (patinas) and the deposition of soil encrustations were also analyzed by means of the FTIR-ATR technique. The molecular analysis confirmed the presence of silico-aluminate minerals on some coins, unequivocally indicating a provenance from clayey soil. Some soil samples, collected from the archaeological site of interest, were analyzed to verify whether the encrusted layer on coins could contain chemical components compatible with them. This result, together with the chemical and morphological investigations, led us to subdivide the six target coins into two groups. The first group is made up of two coins coming from the set of coins from excavation (found in the subsoil) and from the set from open air finds (coins found in the top layer of the soil). The second group is made up of four coins that are devoid of characteristics corresponding to exposure to soil contact for long periods of time and, moreover, their surface compounds could suggest a different provenance. The analytical results of this study made it possible to correctly assign all six coins to the two groups of finds and support numismatics, which was unconvinced in considering all coins to come from the same finding site only on the basis of archaeological documentations.
RESUMO
Lichens belonging to Parmeliaceae are highly diversified, but most of them share an extremely conserved morpho-chemical trait: the lower cortex is heavily melanized. The adaptive value of this character is still uncertain. Melanins are ubiquitous compounds found in most organisms since they fulfil several biological functions including defense against UV radiation, oxidizing agents, microbial stress, and metal complexation. This work aims to establish whether melanization can affect the elemental content of lichen thalli. The relative abundance of macro- (Ca, K and S) and micro- (Fe, Mn and Zn) nutrients in melanized and non-melanized pseudotissues of nine species was first evaluated by a non-destructive micro-X-ray fluorescence elemental analysis on either the upper and lower cortex, and on the internal medulla, which was artificially exposed to the mechanical removal of the lower cortex. Afterwards, the total concentration of the same elements was measured in composite samples by inductively coupled plasma atomic emission spectroscopy after acidic digestion. In order to verify whether Fe and Zn are chemically bound to the melanized pseudotissues, a sequential elution experiment was performed on two species: the two-side heavily melanized Melanelixia glabratula and the one-side lightly melanized Punctelia subrudecta. The content of Fe and Zn was higher in the melanized species than in the non-melanized ones. Species deprived of their melanized lower cortex showed a sharp decrease in Fe but not in Zn, suggesting that the melanized lower cortex is involved in Fe complexation, whereas Zn is homogeneously distributed throughout the thallus.
Assuntos
Líquens/metabolismo , Melaninas/metabolismo , Cálcio/análise , Ferro/análise , Líquens/química , Parmeliaceae/metabolismo , Potássio/análise , Espectrometria por Raios X , Espectrofotometria Atômica , Zinco/análiseRESUMO
The mineral body exploited in Salafossa (Eastern Dolomites) was one of the largest lead/zinc-containing mineral deposits in Europe. Both metals were mainly present as sulphides (sphalerite, ZnS and galena, PbS). Mining activity started around 1550, but it was only around 1960 that the richest veins of the minerals were discovered. The mine closed in 1985, and concentrations of several trace metals, such as thallium (Tl), iron (Fe), manganese (Mn), lead (Pb) and zinc (Zn), were detected in the soils and plant samples (Biscutella laevigata L.) that were collected from eighteen sites selected outside the mine. B. laevigata is a pseudometallophyta species, and it often grows near mining areas where the soil's metal concentrations are significantly higher than those of soil with a natural geochemical background. The total metal concentrations in the plant tissue (roots and leaves of Biscutella laevigata) and in the soil samples - both bulk-soil and the B. laevigata root system (rhizo-soil) - were determined through Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The metal extractability and leachability of the soil samples were estimated using soil extractions with DTPA (Diethylenetriaminepentaacetic acid). In addition, metal mobility caused by rainwater runoff was estimated by using a leaching test with a dilute solution of H2SO4 and HNO3. The results showed that metals were present in a chemical form available for uptake by the plants' roots. In fact, high concentrations of the metals were also found in the plant tissue (roots and leaves) of B. laevigata, and these concentrations were higher than those whose soils present natural geochemical background levels in the corresponding rhizo-soil. Thus, B. laevigata has shown a marked ability to bioaccumulate trace metals, especially Tl and, to a lesser extent, Zn, Pb, Fe and Mn, and it can influence metal mobility in the rhizo-soil. To assess the uptake and translocation processes of the trace metals, resulting in their bioaccumulation, two different indices were calculated: the enrichment factor in roots (EFr), as the ratio between the metal concentration in belowground biomass and in the respective rhizo-soil, and the translocation factor (TF), as the ratio between the metal concentration in the leaves and the corresponding roots. For both indices, values > 1 denoted enrichment of the metal in the roots or its translocation to the upper tissues. The results showed that EFr and TF were considerably high only for Tl, reaching a maximum value of 60 for EFr and 11.6 for TF. Conversely, the other investigated metals did not show significant bioaccumulation (EFr < 1), and they showed TF > 1 only at a few sites.
Assuntos
Brassicaceae/metabolismo , Metais Pesados/farmacocinética , Poluentes do Solo/farmacocinética , Tálio/farmacocinética , Disponibilidade Biológica , Ferro/análise , Ferro/farmacocinética , Itália , Chumbo/análise , Chumbo/farmacocinética , Manganês/análise , Manganês/farmacocinética , Metais Pesados/análise , Mineração , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Solo/química , Poluentes do Solo/química , Sulfetos/análise , Zinco/análise , Zinco/farmacocinética , Compostos de Zinco/análiseRESUMO
Dermal exposure to Aluminium nanoparticles (AlNPs) can occur in occupationally- and non occupationally exposed- population, due to the use of Al salts-based antiperspirants. No AlNPs transdermal permeation data exists. Our study investigated in vitro the permeation of 30-60â¯nm Al2O3NPs dispersed in synthetic sweat (20â¯g/L) using excised human skin on Franz cells. Experiments were performed using intact (experiment 1) and needle-abraded skin (experiment 2). After 24â¯h traces of Al were detectable in receiving solution of exposed cells (35.0⯱â¯6.0â¯ng/cm2 for intact and 88.5⯱â¯34.2â¯ng/cm2 for damaged skin, mean and SD) and in blank cells (36.3⯱â¯7.0â¯ng/cm2), without statistical significance (pâ¯=â¯0.08, Mann-Whitney test). The average amount of Al into intact and damaged skin samples was 3.96⯱â¯0.20⯵g/cm2 for intact and 4.36⯱â¯0.47⯵g/cm2 for damaged skin (pâ¯=â¯0.08). Al content was similar in epidermal and dermal layers of intact and damaged skin (1.95⯱â¯0.13⯵g/cm2 and 2.31⯱â¯0.12⯵g/cm2 epidermal, 2.01⯱â¯0.25⯵g/cm2 and 2.05⯱â¯0.35⯵g/cm2 dermal). Al is a trace element in human body and the amount found in receiving solutions could be due as background impurity. This data suggest a reassuring transdermal permeation profile for Al2O3NPs.
Assuntos
Óxido de Alumínio/metabolismo , Nanopartículas Metálicas , Pele/metabolismo , Idoso , Feminino , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Pele/lesões , Absorção CutâneaRESUMO
The use of palladium (Pd) has grown in the last decades, commonly used in automotive catalytic converters, jewellery and dental restorations sectors. Both general and working population can be exposed to this metal, which may act as skin sensitizer. This study investigated in vitro palladium powders permeation through excised intact and damaged human skin using the Franz diffusion cell method and the effect of rapid skin decontamination using sodium laureth-sulphate. 1â¯mL of a 10â¯min sonicated suspension made of 2.5â¯g of Pd powder in 50â¯mL synthetic sweat at pH 4.5 and room temperature was applied to the outer surface of the skin membranes for 24â¯h. Pd permeation, assessed by ICP-MS, was higher when damaged skin was used (pâ¯=â¯0.03). Final flux permeation values and lag times were 0.02⯱â¯0.01⯵gâ¯cm-2â¯h-1 and 6.00⯱â¯3.95â¯h for intact, and 0.10⯱â¯0.02⯵gâ¯cm-2â¯h-1 and 2.05⯱â¯1.49â¯h for damaged skin samples, respectively. Damaged skin protocol enhances Pd skin penetration inside dermal layer (pâ¯=â¯0.04), thus making the metal available for systemic uptake. Pd penetration (pâ¯=â¯0.02) and permeation (pâ¯=â¯0.012) through intact skin decreased significantly when a cleaning procedure was applied. This study demonstrates that after skin exposure to Pd powders a small permeation of the metal happen both through intact and damaged skin and that an early decontamination with a common cleanser can significantly decrease the final amount of metal available forsystemic uptake.
Assuntos
Paládio/metabolismo , Absorção Cutânea , Pele/metabolismo , Descontaminação , Difusão , Humanos , Cinética , Paládio/toxicidade , Permeabilidade , Pós , Pele/efeitos dos fármacos , Pele/patologia , Absorção Cutânea/efeitos dos fármacos , Dodecilsulfato de Sódio/análogos & derivados , Dodecilsulfato de Sódio/farmacologia , Tensoativos/farmacologiaRESUMO
MnFe2O4 nanoparticles (NPs) are commonly produced in some occupational settings and may reach high concentration in activities such as arc-welding or ferroalloy metallurgy. Manganese is an essential cofactor in enzyme activities but it has been demonstrated that long-term exposure to excessive levels can lead to "manganism", a neurodegenerative disease resembling Parkinson features. Inhaled NPs deposit partially in pharynx and nasopharynx and may reach the central nervous system through the olfactory nerve, which is completely enveloped by the meningeal membranes throughout its course from the nasal cavity to the olfactory bulb or through the trigeminal nerves. This study investigated in vitro the transmeningeal absorption of 50â¯nm MnFe2O4NPs, using excised porcine meninges mounted on Franz diffusion cells. We tested two donor solutions: the first containing MnFe2O4NPs (2.0â¯g/L) and the second obtained by the ultrafiltration of the first one, in order to test only the NPs water soluble fraction. Each experiment was carried separately for 4â¯h. Results showed that no Mn flux permeation through the meninges occurred, since only trace of the metal was found in receivers solutions of cells exposed to MnFeNPs (5.5⯱â¯2.2â¯ng/cm2), ultrafiltered solution (3.5⯱â¯1.5â¯ng/cm2) and blank cells. (2.1⯱â¯0.6â¯ng/cm2) (mean and SE). Differences did not reach the statistical significance. Our study shows - for the first time - that MnFe2O4NPs penetrate the meningeal membrane in a negligible amount, thus making unlikely the hypothesis of a transcellular and paracellular absorption through the olfactory nerve but not excluding the hypothesis of an active intraneuronal absorption.
Assuntos
Compostos Férricos/química , Compostos de Manganês/química , Meninges/metabolismo , Nanopartículas Metálicas/química , Animais , Difusão , Meninges/química , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Permeabilidade , SuínosRESUMO
How best to approach esophagectomy is a controversial issue. In the last decade, the opportunity to use minimally invasive surgical methods for esophagectomy has been documented, but their real advantages over conventional surgery have yet to be clearly established. The aim of this study was to compare a series of patients who underwent laparoscopic esophagectomy with those who underwent open surgery to ascertain the feasibility, safety, and clinical advantages of the former surgical techniques. Between January 2002 and May 2004, 14 patients with cancer of the esophagus underwent laparoscopic esophagectomy and another 14 had conventional open esophagectomy. Their demographic features, and intraoperative and postoperative data were compared. The 2 groups were comparable in terms of age, American Society of Anesthesiologists score, and site of the neoplasm. The operating times were the same for transhiatal laparoscopic esophagectomy and conventional surgery, although using the thoraco-laparoscopic access took longer than the thoraco-laparotomic procedure (P<0.05). The hospital stay was shorter after laparoscopy (P<0.05). No differences emerged in terms of morbidity, mortality, number of transfusions, and time in the intensive care. The numbers of lymph nodes removed were comparable. In conclusion, it is feasible and safe to use a laparoscopic approach instead of open surgery for esophagectomy, but the former does not offer very significant clinical advantages in the postoperative stage. A shorter hospital stay seems to be the most significant finding. The minimally invasive procedure would seem to assure oncological radicality because it enables lymphadenectomy to be as thorough as in the conventional surgical approach.
Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Gastroplastia/métodos , Laparoscopia , Laparotomia , Toracotomia , Adulto , Idoso , Biópsia , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The intensified use of palladium nanoparticles (PdNPs) in many chemical reactions, jewellery, electronic devices, in car catalytic converters and in biomedical applications lead to a significant increase in palladium exposure. Pd can cause allergic contact dermatitis when in contact with the skin. However, there is still a lack of toxicological data related to nano-structured palladium and information on human cutaneous absorption. In fact, PdNPs, can be absorbed through the skin in higher amounts than bulk Pd because NPs can release more ions. In our study, we evaluated the absorption of PdNPs, with a size of 10.7 ± 2.8 nm, using intact and damaged human skin in Franz cells. 0.60 mg cm(-2) of PdNPs were applied on skin surface for 24 h. Pd concentrations in the receiving solutions at the end of experiments were 0.098 ± 0.067 µg cm(-2) and 1.06 ± 0.44 µg cm(-2) in intact skin and damaged skin, respectively. Pd flux permeation after 24 h was 0.005 ± 0.003 µg cm(-2) h(-1) and 0.057 ± 0.030 µg cm(-2) h(-1) and lag time 4.8 ± 1.7 and 4.2 ± 3.6 h, for intact and damaged skin respectively. This study indicates that Pd can penetrate human skin.
Assuntos
Nanopartículas Metálicas , Paládio/farmacocinética , Pele/metabolismo , Idoso , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Absorção CutâneaRESUMO
Nickel nanoparticles (NiNPs) represent a new type of occupational exposure because, due to the small size/high surface, they can release more Ni ions compared to bulk material. It has been reported a case of a worker who developed sensitization while handling nickel nanopowder without precautions. Therefore there is the need to assess whether the skin absorption of NiNPs is higher compared to bulk nickel. Two independent in vitro experiments were performed using Franz diffusion cells. Eight cells for each experiment were fitted using intact and needle-abraded human skin. The donor phase was a suspension of NiNPs with mean size of 77.7 ± 24.1 nm in synthetic sweat. Ni permeated both types of skin, reaching higher levels up to two orders of magnitude in the damaged skin compared to intact skin (5.2 ± 2.0 vs 0.032 ± 0.010 µg cm(-2), p = 0.006) at 24 h. Total Ni amount into the skin was 29.2 ± 11.2 µg cm(-2) in damaged skin and 9.67 ± 2.70 µg cm(-2) in intact skin (mean and SD, p = 0.006). Skin abrasions lead to doubling the Ni amount in the epidermis and to an increase of ten times in the dermis. This study demonstrated that NiNPs applied on skin surface cause an increase of nickel content into the skin and a significant permeation flux through the skin, higher when a damaged skin protocol was used. Preventive measures are needed when NiNPs are produced and used due to their higher potential to enter in our body compared to bulk nickel.