56 research outputs found
Irradiation detection of herbal ingredients used in plant food supplements by Electron Spin Resonance on samples pre-treated with alcoholic extraction
This study aimed to verify the applicability of the EN 1787 method for the detection of irradiation in herbal ingredients used in Plant Food Supplements (PFSs). In matrices such as herbs and spices the main limit of the method is the presence of intrinsic radicals responsible for spurious signals leading to complex ESR spectra. To overcome this limit, before ESR measurement a treatment with alcohol has been proposed (Delincée and Soika, 2002; Ahn et al., 2012, 2014). As reported in the literature, this treatment is expected to reduce/eliminate the confounding signals so that the samples may be correctly classified. In this study the efficacy of the pre-treatment was tested on raw herbal ingredients largely used for PFSs, namely Camellia sinensis, Cinnamomum verum, Curcuma longa, Ginkgo biloba, Silybum marianum, Vaccinium myrtillus and Zingiber officinale. Non-irradiated and irradiated (5, 10 kGy) samples were analysed before and after pre-treatment. The results showed a general decrement of signal intensity. In some cases, this was associated with the elimination of some spurious signals, which, however, did not always ensue in an easier interpretation of the ESR spectra. Only for two matrices (Camellia sinensis and Vaccinium myrtillus) was alcoholic extraction crucial for the correct classification of the samples
Oxidative Stress and Platelet Activation in Homozygous Homocystinuria
Background
—
Severe hyperhomocysteinemia due to cystathionine β-synthase deficiency (CβSD) is associated with early atherothrombotic vascular disease. Homocysteine may exert its effects by promoting oxidative damage. In the present study, we investigated whether in vivo formation of 8-iso-prostaglandin (PG) F
2α
, a platelet-active product of arachidonic acid peroxidation, is enhanced in CβSD and whether it correlates with in vivo platelet activation, as reflected by thromboxane (TX) metabolite excretion.
Methods and Results
—
Urine and blood samples were obtained from patients with homozygous CβSD (n=13) and age-matched healthy subjects. Urinary 8-iso-PGF
2α
excretion was significantly higher in CβSD patients than in control subjects (640±384 versus 213±43 pg/mg creatinine;
P
=0.0015) and correlated with plasma homocysteine (ρ=0.398,
P
=0.0076). Similarly, urinary 11-dehydro-TXB
2
excretion was enhanced in CβSD (1166±415 versus 324±72 pg/mg creatinine;
P
=0.0015) and correlated with urinary 8-iso-PGF
2α
(ρ=0.362,
P
=0.0153). Vitamin E supplementation (600 mg/d for 2 weeks) was associated with a statistically significant increase in its plasma levels (from 16.6±4.6 to 40.4±8.7 μmol/L,
P
=0.0002) and with reductions in 8-iso-PGF
2α
(from 790±159 to 559±111 pg/mg creatinine,
P
=0.018) and 11-dehydro-TXB
2
(from 1273±383 to 913±336 pg/mg creatinine,
P
=0.028). A statistically significant inverse correlation was found between urinary 8-iso-PGF
2α
and plasma vitamin E levels (ρ=−0.745,
P
=0.0135).
Conclusions
—
The results of the present study suggest that enhanced peroxidation of arachidonic acid to form bioactive F
2
-isoprostanes may represent an important mechanism linking hyperhomocysteinemia and platelet activation in CβSD patients. Moreover, they provide a rationale for dose-finding studies of vitamin E supplementation in this setting
An inter-laboratory comparison to evaluate the suitability of EN 1787 standard to detect irradiation in plant-origin foods with health benefits
This paper reports the results of a study carried out to verify the applicability of the EN 1787 method, which uses the Electron Spin Resonance (ESR) technique for the identification of irradiated plant-origin foods with health benefits. The method was tested on samples of herbal ingredients of Plant Food Supplements (PFSs), nuts and fresh blueberries. Untreated and irradiated samples of Camellia sinensis (leaves) Ginkgo biloba (leaves), Glycine max (seeds), Silybum marianum (fruits), Vaccinium myrtillus (fruits), almonds, hazelnuts, peanuts, pistachios, walnuts and fresh blueberries were analysed. The work includes an inter-laboratory blind test involving five Italian laboratories that perform routine analyses for the official control of irradiated food. A total of 180 untreated and irradiated samples of PFS ingredients, nuts and fresh blueberries were analysed. The analyses on the irradiated samples were replicated even a long time after irradiation (up to two years depending on the matrix) to test the reliability of the method throughout the shelf life of the products. The results were matrix-dependent: all the 5 kGy irradiated nuts and the 1 kGy-irradiated blueberries were correctly classified, whereas herbal ingredients showed complex ESR spectra with spurious signals which often prevented the correct classification of the sample
The impact of multidisciplinary team management on outcome of hepatic resection in liver-limited colorectal metastases
Hepatic resection is the gold standard treatment for patients affected by liver-limited colorectal metastases. Reports addressing the impact of multidisciplinary team (MDT) evaluation on survival are controversial. The aim of this study was to evaluate the benefit of MDT management in these patients in our Institution experience. The objective of the analysis was to compare survivals of patients managed within our MDT (MDT cohort) to those of patients referred to surgery from other hospitals without MDT discussion (non-MDT cohort). Of the 523 patients, 229 were included in the MDT cohort and 294 in the non-MDT cohort. No difference between the two groups was found in terms of median overall survival (52.5 vs 53.6 months; HR 1.13; 95% CI, 0.88–1.45; p = 0.344). In the MDT cohort there was a higher number of metastases (4.5 vs 2.7; p < 0.0001). The median duration of chemotherapy was lower in MDT patients (8 vs 10 cycles; p < 0.001). Post-operative morbidity was lower in the MDT cohort (6.2 vs 21.5%; p < 0.001). One hundred and ninety-seven patients in each group were matched by propensity score and no significant difference was observed between the two groups in terms of OS and DFS. Our study does not demonstrate a survival benefit from MDT management, but it allows surgery to patients with a more advanced disease. MDT assessment reduces the median duration of chemotherapy and post-operative morbidities
Serum paraoxonase and arylesterase activities in patients with lung cancer in a Turkish population
BACKGROUND: Lung cancer (LC) is the leading cause of cancer-related deaths. Oxidative DNA damage may contribute to the cancer risk. The antioxidant paraoxonase (PON1) is an endogenous free radical scavenger in the human body. The aim of this study was to determine serum PON1 and arylesterase (ARE) activities in patients with newly diagnosed LC. METHODS: This case control study involved a total of 39 patients with newly diagnosed LC (untreated) and same number of age- and sex-matched healthy individuals. Serum PON1 and ARE activities in addition to lipid parameters were measured in both groups. RESULTS: Serum PON1 and ARE activities were found to be lower in patients with LC compared to the controls (p = 0.001 and p = 0.018, respectively). The ratio of PON1/high density lipoprotein (HDL) was significantly lower in the LC group compared to the control one (p = 0.009). There were positive correlations between the serum levels of HDL and PON1 in both the control (r = 0.415, p = 0.009) and the LC groups (r = 0.496, p = 0.001), respectively. PON1 enzyme activity was calculated as three different phenotypes in both groups. In regard to lipid parameters, total cholesterol levels were significantly lower (p = 0.014) in the LC group whereas the other lipid parameters such as HDL, LDL, and triglyceride levels were not significantly different among groups. CONCLUSION: Serum PON1 activity is significantly low in the LC group compared with the healthy controls. Metastasis status and cigarette smoking do not affect serum PON1 activity in the LC patients
W. Szymborska La gioia di scrivere. Tutte le poesie (1945-2009)
This anthology contains the complete annotated works by Wislawa Szymoborska. Szymborska, currently one of the most well known poets in Italy, was \u201cdiscovered\u201d by Pietro Marchesani, who began to translate her works in 1996, just before the Polish writer was awarded the Nobel Prize for Literature. The volume is enriched by a detailed foreword by Marchesani on Szymborska\u2019s life and oeuvre
Identification and structural analysis of a zebrafish apo and holo cellular retinol-binding protein
Cellular retinol-binding proteins (CRBPs) are cytoplasmic retinol-specific binding proteins. Mammalian CRBPs have been thoroughly characterised previously. Here we report on the identification and X-ray structural analysis of the apo (1.7 Angstrom resolution) and holo (1.4 Angstrom resolution) forms of a zebrafish CRBP. According to amino acid sequence and structure analyses, the zebrafish CRBP that we have identified resembles closely mammalian CRBP 11, suggesting that it is the zebrafish orthologue of this mammalian CRBP type. Zebrafish CRBP forms a tight complex with all-trans retinol, producing an absorption spectrum similar to those of mammalian holo-CRBPs, albeit slightly blue-shifted. The superposition of the alpha-carbon atoms of the liganded (complexed with retinol) and unliganded forms of zebrafish CRBP shows significant differences in correspondence of the betaC-betaD (residues 55-58) and betaE-betaF (residues 74-77) turns, providing evidence for the occurrence of conformational changes accompanying retinol binding/release. Remarkable and well-defined ligand-dependent conformational changes in the protein region comprising the two beta-turns affect both the main chain and the side-chains of several residues. The two beta-turns project towards the interior of the cavity devoid of ligand of the apoprotein. The side-chains of F57, Y60 and L77 change substantially their orientation and position in the apoprotein relative to the holoprotein. In the beta-barrel internal cavity of apo-CRBP they occupy some of the space that is otherwise occupied by bound retinol in holo-CRBP, and are displaced from these positions on ligand binding. These results indicate that a flexible area encompassing the betaC-betaD and betaE-betaF turns may serve as the ligand portal and that these turns undergo conformational changes associated with the not yet clarified mechanism of retinol binding and release in CRBPs
Prove di resistenza all'usura su compositi per I e II classe e su amalgama d'argento
The Authors report the results of an abrasion in vitro test for amalgam alloys and composite resins indicated for restorations of first and second class cavity preparations
Human Serine Racemase Weakly Binds the Third PDZ Domain of PSD-95
Human serine racemase (hSR) is a pyridoxal-5 '-phosphate (PLP)-dependent dimer that catalyzes the formation of D-serine from L-serine, as well as the dehydration of both L- and D-serine to pyruvate and ammonia. As D-serine is a co-agonist of N-methyl-D-aspartate receptors (NMDARs), hSR is a key enzyme in glutamatergic neurotransmission. hSR activity is finely regulated by Mg2+, ATP, post-translational modifications, and the interaction with protein partners. In particular, the C-terminus of murine SR binds the third PDZ domain (PDZ3) of postsynaptic density protein 95 (PSD-95), a member of the membrane-associated guanylate kinase (MAGUK) family involved in the trafficking and localization of glutamate receptors. The structural details of the interaction and the stability of the complex have not been elucidated yet. We evaluated the binding of recombinant human PSD-95 PDZ3 to hSR by glutaraldehyde cross-linking, pull-down assays, isothermal titration calorimetry, nuclear magnetic resonance, and enzymatic assays. Overall, a weak interaction was observed, confirming the binding for the human orthologs but supporting the hypothesis that a third protein partner (i.e., stargazin) is required for the regulation of hSR activity by PSD-95 and to stabilize their interaction
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