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1.
ACS Omega ; 7(32): 27980-27990, 2022 Aug 16.
Article in English | MEDLINE | ID: mdl-35990467

ABSTRACT

Deoxydehydration (DODH) reaction of glycerol (GL) and 1,2-propanediol (1,2-PD), in ionic liquids (ILs), catalyzed by methyltrioxorhenium (MTO) and Re2O7, was studied in detail. To better understand the ability of ILs to improve the catalytic performance of the rhenium catalyst, several experiments, employing eight different cations and two different anions, were carried out. Among the anions, bis(trifluoromethylsulfonyl)imide (TFSI) appears to be more appropriate than PF6 -, for its relatively lower volatility of the resulting IL. Regarding the choice of the most appropriate cation, the presence of a single aromatic ring seems to be a necessary requirement for a satisfying and convenient reactivity. With the aim to extend the recyclability of the catalyst, experiments involving the readdition of polyol to the terminal reaction mixture were carried out. Worthy of interest is the fact that the presence of the IL prevents the inertization process of the catalyst, allowing us to obtain the alkene also after a readdition of fresh polyol.

2.
Article in English | MEDLINE | ID: mdl-35286246

ABSTRACT

Acrylamide (AA) is considered genotoxic, neurotoxic and a 'probable human carcinogen'. It is included in group 2 A of the International Agency for Research on Cancer (IARC). The formation of AA occurs when starch-based foods are subjected to temperatures higher than 120 °C in an atmosphere with very low water content. The aim of this review is to shed light on the toxicological aspects of AA, showing its regulatory evolution, and describing the most interesting mitigation techniques for each food category involved, with a focus on compliance with EU legislation in the various classes of consumer products of industrial origin in Europe.


Subject(s)
Acrylamide , Maillard Reaction , Acrylamide/analysis , Asparagine , Carcinogens , Food , Food Handling/methods , Hot Temperature , Humans
3.
Sci Total Environ ; 684: 445-457, 2019 Sep 20.
Article in English | MEDLINE | ID: mdl-31154217

ABSTRACT

This work focuses on the characterization of background levels of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) in seabed marine sediments of the central Adriatic Sea, collected up to 10 km far from the Abruzzo region coastline (Italy). The used approach follows the guidelines established by the Decree of the Italian Ministry of Environment, n. 173/2016, concerning the determination of threshold values of metal concentration, and including only samples with low or absent toxicological content. A statistical analysis, using the adjusted Tuckey's boxplot to identify the percentiles and potential outliers, was performed. The background concentrations were calculated as the values of the 90th percentile of distribution, according to the national regulation. This study represents the first attempt to calculate the background levels of marine sediments done at regional level in Abruzzo. A few outliers have been found, and interpreted as potential anthropic contamination.

4.
Nanomaterials (Basel) ; 8(10)2018 Oct 19.
Article in English | MEDLINE | ID: mdl-30347698

ABSTRACT

The combination of metal nanoparticles (Pd or Pt NPs) with NAD-dependent thermostable alcohol dehydrogenase (TADH) resulted in the one-flask catalytic double reduction of 3-methyl-2-cyclohexenone to 3-(1S,3S)-methylcyclohexanol. In this article, some assumptions about the interactions between a chemocatalyst and a biocatalyst have been proposed. It was demonstrated that the size of the NPs was the critical parameter for the mutual inhibition: the bigger the NPs, the more harmful for the enzyme they were, even if the NPs themselves were only moderately inactivated. Conversely, the smaller the NPs, the more minimal the TADH denaturation, although they were dramatically inhibited. Resuming, the chemocatalysts were very sensitive to deactivation, which was not related to the amount of enzyme used, while the inhibition of the biocatalyst can be strongly reduced by minimizing the NPs/TADH ratio used to catalyze the reaction. Among some methods to avoid direct binding of NPs with TADH, we found that using large Pd NPs and protecting their surfaces with a silica shell, the overall yield of 3-(1S,3S)-methylcyclohexanol was maximized (36%).

5.
Beilstein J Org Chem ; 13: 19-25, 2017.
Article in English | MEDLINE | ID: mdl-28179944

ABSTRACT

The mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins was investigated in the presence of various poly(ethylene) glycols (PEGs), as safe grinding assisting agents (liquid-assisted grinding, LAG). A comparative study under dry-grinding conditions was also performed. The results showed that the cyclization reaction was influenced by the amount of the PEG grinding agents. In general, cleaner reaction profiles were observed in the presence of PEGs, compared to dry-grinding procedures.

6.
Ann Ital Chir ; 87: 214-9, 2016.
Article in English | MEDLINE | ID: mdl-27346692

ABSTRACT

AIM: Definitive hypoparathyrodism (hypo-PTH) represents one of the most dangerous complication after total thyroidectomy. Partial or total lesion or accidental removal of parathyroid glands is an unpredictable adverse event, although real incidence is not well defined, such as management of this deficit. We started a prospective evaluation of patients treated with total thyroidectomy in our centre, to identify incidence of hypo-PTH, symptomatic or not, in relation to incidence of early postoperative hypocalcemia in our experience. METHODS: We prospectively evaluated 177 patients treated for benign and malign pathology, measuring calcium before surgery and calcium and PTH at least three months after surgery. Postoperative hypocalcemia was observed in 37.3% of cases. Eight patients (4.5% of cohort) presented low level of PTH, at mean follow-up of 9.1 months. Positive predictive value for postoperative hypocalcemia was 12.1%, while negative predictive was 95.4%; confirming high sensitivity (100%) and low specificity (65.4%) for detecting hypo-PTH. DISCUSSION: All patients with late hypo-PTH presented hypocalcemia on early analysis, while no case with normal postoperative calcemia accounted with hypo-PTH: this may indicate calcemia as valid prognostic factor of good gland production, when is in the range. Moreover, isolated analysis is too limited to determine real predictability. CONCLUSION: Technical standardization represents the best method for prevention of hypo-PTH. Early hypocalcemia is a prognostic factor, even with a low specificity, of deficit of PTH-production. This observation must be related to other known prognostic factors. Postoperative normal calcemia should be a positive prognostic factor of an acceptable PTHfunction, supported by large cohorts. KEY WORDS: Hypocalcemia, Parathormone, Thyroidectomy.


Subject(s)
Hypocalcemia/complications , Hypoparathyroidism/etiology , Postoperative Complications/etiology , Thyroidectomy/adverse effects , Adult , Aged , Female , Humans , Hypoparathyroidism/epidemiology , Incidence , Male , Middle Aged , Postoperative Complications/epidemiology , Prospective Studies , Risk Assessment , Thyroidectomy/methods
7.
J Phys Chem Lett ; 7(10): 1934-8, 2016 May 19.
Article in English | MEDLINE | ID: mdl-27193088

ABSTRACT

The rhenium dioxide anion [ReO2](-) reacts with carbon dioxide in a linear ion trap mass spectrometer to produce [ReO3](-) corresponding to activation and cleavage of a C-O bond. Isotope labeling experiments using [Re(18)O2](-) reveal that (18)O/(16)O scrambling does not occur prior to cleavage of the C-O bond. Density functional theory calculations were performed to examine the mechanism for this oxygen atom abstraction reaction. Because the spins of the ground states are different for the reactant and product ions ((3)[ReO2](-) versus (1)[ReO3](-)), both reaction surfaces were examined in detail and multiple [O2Re-CO2](-) intermediates and transition structures were located and minimum energy crossing points were calculated. The computational results show that the intermediate [O2Re(η(2)-C,O-CO2)](-) species most likely initiates C-O bond activation and cleavage. The stronger binding affinity of CO2 within this species and the greater instabilities of other [O2Re-CO2)](-) intermediates are significant enough that oxygen atom exchange is avoided.

8.
ACS Omega ; 1(3): 464-469, 2016 Sep 30.
Article in English | MEDLINE | ID: mdl-30023483

ABSTRACT

The use of particulate titanium dioxide (TiO2) as an active sunscreen ingredient has raised concerns about potential risks from TiO2-mediated free radical formation. To date, remediation attempts have concentrated on reducing the yield of free radical generation by TiO2 upon sunlight exposure. The problem with this approach is that given the band gap in TiO2, production of radical and the ensuing reactive oxygen species (ROS) is completely normal. Our strategy is based on a nontoxic, biocompatible shell that neutralizes the free radicals by scavenging them with natural antioxidants before they exit the particle. The new lignin@TiO2 composites preserve the scattering and absorption properties of TiO2 because the particles retain their nanoscale dimensions as preferred by the cosmetic industry. Although the target properties for photocatalysis and sun-protection applications are opposite, we argue that exactly the same knowledge is required to optimize either one.

9.
Eur J Mass Spectrom (Chichester) ; 21(3): 557-68, 2015.
Article in English | MEDLINE | ID: mdl-26307735

ABSTRACT

The ion-molecule reactions of the rhenium oxide anions, [ReOx](-) (x = 2 - 4) with the organic substrates methane, ethene, methanol and acetic acid have been examined in a linear ion trap mass spectrometer. The only reactivity observed was between [ReO(2)](-) and acetic acid. Isotope labelled experiments and high-resolution mass spectrometry measurements were used to assign the formulas of the ionic products. Collision-induced dissociation and ion-molecule reactions with acetic acid were used to probe the structures of the mass-selected primary product ions. Density functional theory calculations [PBE0/LanL2DZ6-311+G(d)] were used to suggest possible structures. The three primary product channels observed are likely to arise from the formation of: the metallalactone [ReO(2)(CH(2)CO(2))](-) (m/z 277) and H(2); [CH(3)ReO(2)(OH)](-) (m/z 251) and CO; and [ReO(3)](-) (m/z 235), H(2) and CH(2)CO.

10.
Biometals ; 27(3): 575-89, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24699848

ABSTRACT

Breast cancer represents the second cause of death in the European female population. The lack of specific therapies together with its high invasive potential are the major problems associated to such a tumor. In the last three decades platinum-based drugs have been considered essential constituents of many therapeutic strategies, even though with side effects and frequent generation of drug resistance. These drugs have been the guide for the research, in last years, of novel platinum and ruthenium based compounds, able to overcome these limitations. In this work, ruthenium and platinum based phthalocyanines were synthesized through conventional techniques and their antiproliferative and/or cytotoxic actions were tested. Normal mammary gland (MCF10A) and several models of mammarian carcinoma at different degrees of invasiveness (BT474, MCF-7 and MDA-MB-231) were used. Cells were treated with different concentrations (5-100 µM) of the above reported compounds, to evaluate toxic concentration and to underline possible dose-response effects. The study included growth curves made by trypan blue exclusion test and scratch assay to study cellular motility and its possible negative modulation by phthalocyanine. Moreover, we investigated cell cycle and apoptosis through flow cytometry and AMNIS Image Stream cytometer. Among all the tested drugs, tetrasulfonated phthalocyanine of platinum resulted to be the molecule with the best cytostatic action on neoplastic cell lines at the concentration of 30 µM. Interestingly, platinum tetrasulfophtalocyanine, at low doses, had no antiproliferative effects on normal cells. Therefore, such platinum complex, appears to be a promising drug for mammarian carcinoma treatment.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Indoles/pharmacology , Organoplatinum Compounds/pharmacology , Water/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Cell Cycle/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Female , Humans , Indoles/chemistry , Indoles/metabolism , MCF-7 Cells , Organoplatinum Compounds/chemistry , Organoplatinum Compounds/metabolism , Solubility
11.
Dalton Trans ; 43(20): 7473-9, 2014 May 28.
Article in English | MEDLINE | ID: mdl-24622601

ABSTRACT

The preparation of new Pc-SWCNT hybrid materials is described. The synthesis of both Pd(ii)Pc-SWCNT and Ru(ii)bis(pyridine)Pc-SWCNT was carried out by esterification reaction between modified SWCNTs and the corresponding unsymmetric Pcs and , both endowed with three solubilizing tert-butyl groups and a hydroxymethyl function. Compound was prepared following the straightforward, statistical condensation of the corresponding phthalonitriles. However the preparation of Ru(ii)bis(pyridine)Pc required a multistep procedure relying on consecutive cyclotetramerization, protection, metallation and deprotection reactions. Modified SWCNT was prepared, as previously described, by the Prato reaction between HiPCo nanotubes, N-methylglycine and 4-formylbenzoic acid. The COOH-containing material was successfully reacted with Pd(ii)Pc to give Pd(ii)Pc-SWCNT , which was fully characterized by different techniques. However, the incorporation of Ru(ii)bis(pyridine)Pc did not take place when applying the above-mentioned conditions. The preparation of SWCNT endowed with 4-carboxyphenyl moieties was found to be essential to covalently link Ru(bis(pyridine))Pc to the nanotube material by ester bond formation. Although spectroscopic characterization supports the covalent binding of Pc molecules to the modified SWCNT sidewalls, direct evidence of the presence of Ru(ii) in the hybrid material could not be obtained.

12.
Ann Ital Chir ; 85(6): 537-43, 2014.
Article in English | MEDLINE | ID: mdl-25712947

ABSTRACT

AIM: Fine-needle aspiration (FNA) has proven to be a safe and reliable method of investigation of thyroid lesions. Referencing to European classification, the associated risk of malignancy for TIR3, category reserved for aspirates that contain architectural and/or nuclear atypia, is variable in such studies. Aims of study were evaluating safety of surgical approach, assessing perioperative parameters surgically related, and estimating neoplastic rate for TIR3 group. MATERIAL AND METHODS: A prospective evaluation of all TIR3 submitted to thyroidectomy was conducted by assessing histopatohologic results between January 2005 and December 2012, considering two categories, positive (neoplastic) and negative (not neoplastic) group. Intraoperative and complication rate was analyzed on TIR3 population. RESULTS: A total of 1514 total thyroidectomy was performed from 2005 to 2012: a total of 148 cases was considered on TIR3 group. Positive cases amounted to 64 (43.2%), 29 of which were carcinoma (19.6% of total population) and 35 of which were adenoma, while negative cases amounted to 84 (56.8%). Sensitivity and specificity of TIR3 as neoplastic screening was 43.2% and 82.1%. A total of 32 linfectomies was performed (21.6% of group). Positive group presented a significant lower mean age than negative group (42.1 vs 56.2 years) CONCLUSIONS: TIR3 group represents a various category, with probably different malignancy risk. Our results and neoplasms rate confirmed that surgical option should be gold standard, in order to define atypical pattern and reduce delayed diagnoses. Choice of a second FNA or a imaging monitoring should be adopted for specific condition. KEY WORDS: Fine-needle aspiration, Thyroidectomy, TIR3, Thyroid cancer.


Subject(s)
Adenoma , Biopsy, Fine-Needle , Carcinoma , Thyroid Gland/pathology , Thyroid Neoplasms , Thyroidectomy , Adenoma/epidemiology , Adenoma/pathology , Adenoma/surgery , Adult , Carcinoma/epidemiology , Carcinoma/pathology , Carcinoma/surgery , Cytodiagnosis/methods , Female , Humans , Italy/epidemiology , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Sensitivity and Specificity , Thyroid Neoplasms/epidemiology , Thyroid Neoplasms/pathology , Thyroid Neoplasms/surgery
13.
J Chromatogr A ; 1312: 58-68, 2013 Oct 18.
Article in English | MEDLINE | ID: mdl-24028933

ABSTRACT

Among the commercial ethylenediamine-N,N'-bis(2-hydroxy)phenylacetic acid/iron(III) derivatives, ethylenediamine-N,N'-bis(2-hydroxy-5-sulphophenylacetic) acid/iron(III) (EDDHSA/Fe) represents one of the promising chelates for the treatment of chlorotic plants. Industrial synthesis of EDDHSA/Fe leads to relevant amounts of o,o-EDDHSA condensation products (o,o-EDDHSAcps) and other secondary products that might have important relevance from the agronomic point of view. However, their chemical structures have remained unknown to date. Analysis of iron complexes by ion-pair reversed-phase chromatography, coupled with electrospray tandem mass spectrometry revealed the presence of the meso-o,o-EDDHSA/Fe, rac-o,o-EDDHSA/Fe, o,p-EDDHSA/Fe regioisomers, the hydroxyl derivative of o,o-EDDHSA/Fe, and the three main EDDHSA condensation products chelating the iron(III) (EDDHSAcps/nFe). However, the chromatographic peaks of EDDHSAcps/Fe are not well resolved due to the large numbers of stereoisomers and the poor efficiency of the ion-pair reversed-phase separation method. An alternative chromatographic method is based on porous graphitic carbon (PGC) separation after pre-column decomplexation of the chelates with trifluoracetic acid, which was developed to allow detection of EDDHSA stereo/regioisomers, EDDHSAcps, and low-molecular-weight by-products. This extensive PGC-HPLC-ESI-MS/MS investigation provides quantitative determination of meso-o,o-EDDHSA, rac-o,o-EDDHSA and o,p-EDDHSA, in addition to characterisation of EDDHSAcps and the low-molecular-weight by-products. PGC separation coupled to a triple quadrupole ESI-MS detector allowed characterisation of free ligands using collision-induced dissociation experiments in positive and negative ionisation mode, providing comparative evaluation of EDDHSAcps in three commercial samples. For detection, the PGC-HPLC-ESI-MS/MS is the best method according to the limit of quantification and limit of detection (picomolar and sub-picomolar detection, respectively) for determination of meso-EDDHSA and rac-o,o-EDDHSA. Synthesis, purification and quantification of o,o-EDDHSA and o,p-EDDHSA by (1)H-nuclear magnetic resonance are also reported.


Subject(s)
Chromatography, High Pressure Liquid/methods , Graphite/chemistry , Phenylacetates/analysis , Phenylacetates/chemistry , Tandem Mass Spectrometry/methods , Ions/chemistry , Sensitivity and Specificity , Spectrometry, Mass, Electrospray Ionization , Stereoisomerism
14.
J Biomed Sci ; 17: 14, 2010 Feb 23.
Article in English | MEDLINE | ID: mdl-20178616

ABSTRACT

BACKGROUND: Both hypoxia and hyperoxia, deregulating the oxidative balance, may play a role in the pathology of neurodegenerative disorders underlain by cerebral ischemia. In the present study, quantitative proton magnetic resonance spectroscopy was used to evaluate regional metabolic alterations, following a 24-hour hypoxic or hyperoxic exposure on the background of ischemic brain insult, in two contrasting age-groups of rats: young--3 months old and aged--24 months old. METHODS: Cerebral ischemia was induced by ligation of the right common carotid artery. Concentrations of eight metabolites (alanine, choline-containing compounds, total creatine, gamma-aminobutyric acid, glutamate, lactate, myo-inositol and N-acetylaspartate) were quantified from extracts in three different brain regions (fronto-parietal and occipital cortices and the hippocampus) from both hemispheres. RESULTS: In the control normoxic condition, there were significant increases in lactate and myo-inositol concentrations in the hippocampus of the aged rats, compared with the respective values in the young ones. In the ischemia-hypoxia condition, the most prevalent changes in the brain metabolites were found in the hippocampal regions of both young and aged rats; but the effects were more evident in the aged animals. The ischemia-hyperoxia procedure caused less dedicated changes in the brain metabolites, which may reflect more limited tissue damage. CONCLUSIONS: We conclude that the hippocampus turns out to be particularly susceptible to hypoxia overlaid on cerebral ischemia and that old age further increases this susceptibility.


Subject(s)
Brain Ischemia/metabolism , Brain/metabolism , Hyperoxia/metabolism , Hypoxia-Ischemia, Brain/metabolism , Aging/metabolism , Animals , Animals, Newborn , Brain Ischemia/complications , Female , Hyperoxia/complications , Magnetic Resonance Spectroscopy , Male , Protons , Rats , Rats, Sprague-Dawley
15.
Tumori ; 93(1): 103-5, 2007.
Article in English | MEDLINE | ID: mdl-17455881

ABSTRACT

The presence of an adrenal gland nodule may be an early or late sign of metastatic spread from colorectal cancer. It usually appears when the internal malignancy is widely disseminated and has been previously diagnosed. Adrenal insufficiency can be compatible with bilateral and diffuse involvement of this uncommon site of disease. Although a surgical approach can be proposed in some circumstances, chemotherapy is usually the only therapeutic option. We present 2 cases that document examples of both events, so as to illustrate the most relevant aspects of this condition.


Subject(s)
Adenocarcinoma/secondary , Adrenal Gland Neoplasms/secondary , Colorectal Neoplasms/pathology , Adenocarcinoma/complications , Adrenal Gland Neoplasms/complications , Aged , Colorectal Neoplasms/complications , Humans , Male , Middle Aged , Nephrectomy , Nephrolithiasis/complications , Nephrolithiasis/surgery , Positron-Emission Tomography , Tomography, X-Ray Computed
16.
J Agric Food Chem ; 52(5): 1228-33, 2004 Mar 10.
Article in English | MEDLINE | ID: mdl-14995126

ABSTRACT

A novel system was investigated, finalized to reduce the impact of highly polluting wastewaters, and based on combined actions of catalytic oxidations and microbial biotechnologies. Olive oil mill wastewaters (COD 10,000-100,000 mg O(2)/L) were oxidized up to 80-90% by stoichiometric amounts of dilute hydrogen peroxide (35%) and in the presence of water soluble iron catalysts, either Fe(II) or Fe(III), at concentrations up to 1% w/w and more, i.e., much larger than those reported for conventional Fenton processes. In the combined action, the mineralization activity of a selected microbial consortium was used to degrade residual volatile and nonvolatile organic compounds into CO(2) and biomass. The results of this search could suggest an improved operational methodology capable to reduce the potential impact of wastewater.


Subject(s)
Food Handling , Industrial Waste , Plant Oils , Water Pollutants , Bacteria/metabolism , Biotechnology , Iron/chemistry , Olive Oil , Oxidation-Reduction , Water Pollutants/metabolism
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