Size-segregated content of heavy metals and polycyclic aromatic hydrocarbons in airborne particles emitted by indoor sources.

Indoor air quality is negatively affected by the emission of different combustion sources releasing airborne particles and related particle-bound toxic compounds (e.g., heavy metals and polycyclic aromatic hydrocarbons). To date, very few studies focused on the chemical characterization of the airborne particles emitted by indoor sources were carried out; moreover, no data on their size-resolved chemical compositions are available. In the present study, an experimental analysis aimed at determining the size-segregated content of heavy metals and polycyclic aromatic hydrocarbons in airborne particles (including sub-micrometric ones) emitted by widely-used indoor combustion sources (i.e., incenses, candles, mosquito-coils, and cooking activities) was carried out. To this purpose, airborne particles were collected through an electric low-pressure impactor and were post-analyzed by means of chromatography-mass spectrometry and atomic emission spectrometry techniques. Results of the analyses showed that the chemical composition of the emitted particles is not invariant to the particle size, indeed, an important contribution of sub-micrometric particle range to the total mass of chemical compounds emitted by the sources was noticed. These findings also demonstrated that significant underestimations of particle-bound compounds depositing in the lungs could occur if size-dependent compositions are not adopted.

A different perspective on sofosbuvir-ledipasvir treatment of patients with HCV genotype 1b cirrhosis: The ital-c network study.

The effectiveness of a 12-week course of sofosbuvir-ledipasvir in treatment-experienced HCV genotype 1b-infected patients with cirrhosis is still under debate. Our primary endpoint was to compare the sustained virological response at post-treatment week 12 (SVR12) of sofosbuvir-ledipasvir in combination with ribavirin for 12 weeks, and sofosbuvir-ledipasvir alone for 24 weeks. This was a prospective observational study that enrolled 424 (195 naive, 229 experienced; 164 treated for 12 weeks with Ribavirin and 260 with sofosbuvir-ledipasvir alone for 24 weeks) consecutive HCV genotype 1b-infected patients with cirrhosis. The SVR12 rates were 93.9% and 99.2% in patients treated for 12 and 24 weeks, respectively (P = .002). The baseline characteristics of patients treated for 12 weeks were significantly different from those treated for 24 weeks as regards their younger age (P = .002), prevalence of Child-Pugh class A (P = .002), lower MELD scores (P = .001) and smaller number of nonresponders (P = .04). The shorter treatment was significantly associated with a lower SVR12 in univariate and multivariate analyses (P = .007 and P = .008, respectively). The SVR rate was unaffected by age, gender, BMI, Child-Pugh class, MELD score or previous antiviral treatment. Patients receiving ribavirin experienced more episodes of ascites and headache but less recurrence of hepatocellular carcinoma (HCC), and were prescribed more diuretics and cardiopulmonary drugs. No patient discontinued treatment. The therapeutic regimen of sofosbuvir-ledipasvir plus ribavirin administered for 12 weeks was less effective than sofosbuvir-ledipasvir alone given for 24 weeks. At odds with European guidelines, the recommended 12-week treatment with sofosbuvir-ledipasvir alone might be suboptimal for this setting of patients.

Effect of diets supplemented with different conjugated linoleic acid (CLA) isomers on protein expression in C57/BL6 mice.

BACKGROUND: The individual genetic variations, as a response to diet, have recently caught the attention of several researchers. In addition, there is also a trend to assume food containing beneficial substances, or to supplement food with specific compounds. Among these, there is the conjugated linoleic acid (CLA), which has been demonstrated to reduce fat mass and to increase lean mass, even though its mechanism of action is still not known. We investigated the effect of CLA isomers (CLA c9,t11 and CLA t10,c12) on the proteomic profile of liver, adipose tissue, and muscle of mouse, with the aim of verifying the presence of a modification in fat and lean mass, and to explore the mechanism of action. METHODS: C57/BL6 mice were fed for 2 months with different diets: (1) standard chow, (2) CLA c9,t11 diet, (3) CLA t10,c11 diet, (4) CLA isomers mixture diet, and (5) linoleic acid diet. The proteomic profile of liver, white adipose tissue, and muscle was investigated. Statistical significance of the spots with an intensity higher than twofold in expression compared to the control was tested using student's t test (two-tail). RESULTS: We found that both isomers modulate the proteomic profiles of liver, adipose tissue, and muscle by different mechanisms of action. Liver steatosis is mostly due to the isomer CLA t10,c12, since it alters the expression of lipogenetic proteins; it acts also reducing the adipose tissue and increasing fatty acid oxidation in muscle. Conversely, CLA c9,t11 has no relevant effects on liver and adipose tissue, but acts mostly on muscle, where it enhances muscular cell differentiation. CONCLUSIONS: Administration of CLA in humans has to be carefully personalized, since even considering the presence of a species-specific effect, adverse effects might occur on long-term supplementation. Here we demonstrated that, in mouse, CLA is effective in reducing fat mass, but it also induces liver steatosis. The increase of lean mass is linked to an induction of cell proliferation, which, on long-term supplementation, might also lead to adverse effects.

Conjugated linoleic acid isomers modulate protein expression profile in rat hepatocytes.

Conjugated linoleic acid (CLA) is a polyunsaturated fatty acid, which has been recently proven to be effective in reducing body fat mass, but brings as a side effect, the liver enlargement due to an increased lipid content. The in vivo lipogenic activity has been suggested to be due to the reduction in fat mass and to the consequent metabolism of blood glucose to fatty acid in the liver rather than in the adipose tissue. We investigated the ability of CLA to directly induce steatosis by modulating the expression pattern of hepatic proteins involved in lipid metabolism. To avoid interferences derived from CLA metabolism by other tissues, we used the in vitro model of freshly isolated rat hepatocytes incubated in the presence of different CLA isomers. The direct effect of CLA on lipid accumulation in hepatocytes was demonstrated by the altered expression pattern of several proteins involved in lipid metabolism, as assessed by two-dimensional gel electrophoresis and confirmed by Western blotting analysis. The CLA isomer c9,t11 was most effective in modulating the protein expression profile.

The impact of proteomics in the understanding of the molecular basis of Paclitaxel-resistance in ovarian tumors.

The current therapy for ovarian cancer has advanced from alkylating agents, to a combination of carboplatinum and paclitaxel offering increased survival. Although most patients respond to this first-line therapy, initially, the majority of these patients relapse within 2 years. The mechanisms responsible for acquired drug resistance in ovarian cancer have been elucidated only in part. They include i) enhanced drug export, ii) activation/inhibition of intracellular signalling pathways, iii) molecular alterations in tubulin isotype composition. A better understanding of these mechanisms is needed, in order to develop new approaches, aimed at overcoming resistance to anticancer agents, and to reveal the complexity of causes, which contribute to drug resistance. In this review we offer an updated overview of proteomic studies on the molecular mechanisms of paclitaxel resistance. These proteomic studies also identify potential targets for modulating drug resistance, that could be predictive of response to chemotherapy in ovarian carcinomas.

Selective melanocortin MC4 receptor agonists reverse haemorrhagic shock and prevent multiple organ damage.

BACKGROUND AND PURPOSE: In circulatory shock, melanocortins have life-saving effects likely to be mediated by MC4 receptors. To gain direct insight into the role of melanocortin MC4 receptors in haemorrhagic shock, we investigated the effects of two novel selective MC4 receptor agonists. EXPERIMENTAL APPROACH: Severe haemorrhagic shock was produced in rats under general anaesthesia. Rats were then treated with either the non-selective agonist [Nle4, D-Phe7]-melanocyte-stimulating hormone (NDP--MSH) or with the selective MC4 agonists RO27-3225 and PG-931. Cardiovascular and respiratory functions were continuously monitored for 2 h; survival rate was recorded up to 24 h. Free radicals in blood were measured using electron spin resonance spectrometry; tissue damage was evaluated histologically 25 min or 24 h after treatment. KEY RESULTS: All shocked rats treated with saline died within 30-35 min. Treatment with NDP--MSH, RO27-3225 and PG-931 produced a dose-dependent (13-108 nmol kg-1 i.v.) restoration of cardiovascular and respiratory functions, and improved survival. The three melanocortin agonists also markedly reduced circulating free radicals relative to saline-treated shocked rats. All these effects were prevented by i.p. pretreatment with the selective MC4 receptor antagonist HS024. Moreover, treatment with RO27-3225 prevented morphological and immunocytochemical changes in heart, lung, liver, and kidney, at both early (25 min) and late (24 h) intervals. CONCLUSIONS AND IMPLICATIONS: Stimulation of MC4 receptors reversed haemorrhagic shock, reduced multiple organ damage and improved survival. Our findings suggest that selective MC4 receptor agonists could have a protective role against multiple organ failure following circulatory shock.

Distribution of killer cell immunoglobulin-like receptors genes in the Italian Caucasian population.

BACKGROUND: Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activatory receptors that are expressed by most natural killer (NK) cells. The KIR gene family is polymorphic: genomic diversity is achieved through differences in gene content and allelic polymorphism. The number of KIR loci has been reported to vary among individuals, resulting in different KIR haplotypes. In this study we report the genotypic structure of KIRs in 217 unrelated healthy Italian individuals from 22 immunogenetics laboratories, located in the northern, central and southern regions of Italy. METHODS: Two hundred and seventeen DNA samples were studied by a low resolution PCR-SSP kit designed to identify all KIR genes. RESULTS: All 17 KIR genes were observed in the population with different frequencies than other Caucasian and non-Caucasian populations; framework genes KIR3DL3, KIR3DP1, KIR2DL4 and KIR3DL2 were present in all individuals. Sixty-five different profiles were found in this Italian population study. Haplotype A remains the most prevalent and genotype 1, with a frequency of 28.5%, is the most commonly observed in the Italian population. CONCLUSION: The Italian Caucasian population shows polymorphism of the KIR gene family like other Caucasian and non-Caucasian populations. Although 64 genotypes have been observed, genotype 1 remains the most frequent as already observed in other populations. Such knowledge of the KIR gene distribution in populations is very useful in the study of associations with diseases and in selection of donors for haploidentical bone marrow transplantation.

Hierarchy of baby-linked immunogenetic risk factors in the vertical transmission of hepatitis C virus.

Mother-to-infant transmission of Hepatitis C Virus (HCV) represents the major cause of pediatric HCV infection today. Immunogenetic influence has been poorly investigated and mainly confined to HLA-class II serological polymorphisms. Among 290 parities, 135 from Pavia and 155 from Bergamo, of HCV-RNA-infected Italian women, 21 babies (7.24%) were HCV-RNA positive at birth and steadily positive over 20 months of life. All the 21 infected babies and 44 randomly selected uninfected ones, born to HCV-RNA+ mothers but steadily negative for HCV-RNA during a follow-up of 2 years, and their mothers were investigated for HLA-G, -C, -DRB1, -DQA1 and -DQB1 genomic polymorphisms. Among the different covariates, HLA-Cw*07, -G*010401, -DRB1*0701, -DRB1*1401 and homozygosity for HLA-G 14bp deletion can be considered as risk factors for HCV vertical transmission. On the contrary, protection was conferred by the HLA-DQB1*06, -G*0105N, -Cw*0602, DRB1*1104 and -DRB1*1302 alleles. Our initial question was: has the immunogenetic profile any role in the protection of the fetus growing in an infected milieu and, if so, is it independent from the other non-immunogenetic parameters? The answer to both questions should be yes.

Helicobacter pylori infection and autoimmune thyroid disease in young patients: the disadvantage of carrying the human leukocyte antigen-DRB1*0301 allele.

CONTEXT AND OBJECTIVE: Pathogenesis of autoimmune thyroid disease (ATD) is multifactorial. Helicobacter pylori (Hp) infection has been proposed to be involved in nongastrointestinal conditions and reported more frequently in ATD adult patients. We evaluated the prevalence of Hp antibodies in young ATD patients and investigated the possibility that a susceptible immunogenetic profile could influence the development of ATD in subjects with Hp infection. SUBJECTS AND METHODS: We retrospectively studied 90 children with ATD (median age 11.2 yr), 70 age- and sex-matched healthy subjects as controls, and 65 patients with Turner syndrome (median age 18.8 yr). Antibodies to Hp were determined at diagnosis in ATD patients and, in Turner patients, at the last control in cases without ATD and before the appearance of thyroid autoantibodies in the others. Serological and molecular human leukocyte antigen (HLA) typing for classes I and II polymorphisms was performed. RESULTS: Prevalence of positive Hp serology resulted significantly higher in ATD patients than controls (P = 0.032). No association was found between individual HLA alleles and Hp serology. HLA-A1, B8, and DRB1*0301 were found significantly associated with ATD. A significant interaction between HLA-DRB1*0301 and Hp infection was present in ATD patients and not controls (P = 0.007), suggesting that the copresence of these two factors might favor ATD development. A similar phenomenon was observed in Turner syndrome patients (P = 0.02; cumulative Mantel test, P = 0.0001). CONCLUSIONS: Another target of Hp-elicited immune inflammatory response might be the thyroid gland in subjects with a peculiar immunogenetic profile so that ATD may be a consequence. Our findings suggest the opportunity of eradicating Hp infection in children with ATD and/or susceptible HLA alleles.

Donor-recipient incompatibility at CD31-codon 563 is a major risk factor for acute graft-versus-host disease after allogeneic bone marrow transplantation from a human leucocyte antigen-matched donor.

Disparities at minor histocompatibility antigens (mHA) are thought to be responsible for acute graft-versus-host disease (aGVHD) in patients receiving bone marrow transplantation (BMT) from a human leucocyte antigen (HLA)-matched donor. Although some mHA have been identified in humans, their role in aGVHD has not. Patients (n = 150) receiving a BMT from an HLA-matched donor were investigated for a correlation between aGVHD and donor/recipient incompatibility for seven polymorphisms previously proposed for mHA (HA-1, H-Y, CD31-codon 125, CD31-codon 563, HPA-1, HPA-3 and HPA-5). Only mismatch at CD31-codon 563 predicted grade II-IV aGVHD. The risk derived from CD31-codon 563 mismatch was the same as that derived from the use of bone marrow from an unrelated donor. We suggest that donor/recipient compatibility at CD31-codon 563 should be added to HLA-typing for donor selection and/or adjustment of aGVHD prophylaxis.

N-acetylcysteine inhibits in vivo nitric oxide production by inducible nitric oxide synthase.

This in vivo study evaluates the effect of N-acetylcysteine (NAC) administration on nitric oxide (NO) production by the inducible form of nitric oxide synthase (iNOS). NO production was induced in the rat by the ip administration of 2 mg/100 g lipopolysaccharide (LPS). This treatment caused: (1) a decrease in body temperature within 90 min, followed by a slow return to normal levels; (2) an increase in plasma levels of urea, nitrite/nitrate, and citrulline; (3) the appearance in blood of nitrosyl-hemoglobin (NO-Hb) and in liver of dinitrosyl-iron-dithiolate complexes (DNIC); and (4) increased expression of iNOS mRNA in peripheral blood mononuclear cells (PBMC). Rat treatment with 15 mg/100 g NAC ip, 30 min before LPS, resulted in a significant decrease in blood NO-Hb levels, plasma nitrite/nitrate and citrulline concentrations, and liver DNIC complexes. PBMC also showed a decreased expression of iNOS mRNA. NAC pretreatment did not modify the increased levels of plasma urea or the hypothermic effect induced by the endotoxin. The administration of NAC following LPS intoxication (15 min prior to sacrifice) did not affect NO-Hb levels. These results demonstrate that NAC administration can modulate the massive NO production induced by LPS. This can be attributed mostly to the inhibitory effect of NAC on one of the events leading to iNOS protein expression. This hypothesis is also supported by the lack of effect of late NAC administration.

Maximal endothelial tissue plasminogen activator release is not impaired in patients with acute coronary syndromes before heparin treatment.

Procoagulant and fibrinolytic disturbances are described in patients with acute coronary syndromes (ACS), but whether defective maximal tissue plasminogen activator (t-PA) release from the endothelium is also present is still controversial. Previous studies did not take into consideration the contribution of heparin, which strongly affects fibrinolysis. Accordingly, in this study, we measured maximal t-PA release in patients with ACS before, during, and after heparin treatment. Maximal t-PA release was measured by the venous occlusion test in 38 hospitalized patients with confirmed ACS (18 acute myocardial infarctions and 20 unstable anginas) before starting heparin, during heparin treatment, and 4 and 12 h after discontinuation. Plasma plasminogen activator inhibitor type 1 (PAI-1), D-dimer and prothrombin fragment F1 + 2 were also measured. Eighteen age-matched subjects with no evidence of coronary disease were used as controls. At admission, patients showed significantly higher plasma levels of t-PA, PAI-1, and F1 + 2 than controls. Before heparin, maximal t-PA release was similar in patients and controls. Heparin treatment was associated with a significant increase of plasma t-PA, while it did not affect maximal t-PA release. Coagulative and fibrinolytic disturbances are present in patients with ACS, but these do not include maximal t-PA release. Among our patients, maximal t-PA release appears stable over time and is not affected by heparin treatment.

Antioxidative efficacy of parallel and combined supplementation with coenzyme Q10 and d-alpha-tocopherol in mildly hypercholesterolemic subjects: a randomized placebo-controlled clinical study.

It has been claimed that coenzyme Q10 (Q10) would be an effective plasma antioxidant since it can regenerate plasma vitamin E. To test separate effects and interaction between Q10 and vitamin E in the change of plasma concentrations and in the antioxidative efficiency, we carried out a double-masked, double-blind clinical trial in 40 subjects with mild hypercholesterolemia undergoing statin treatment. Subjects were randomly allocated to parallel groups to receive either Q10 (200 mg daily), d-alpha-tocopherol (700 mg daily), both antioxidants or placebo for 3 months. In addition we investigated the pharmacokinetics of Q10 in a separate one-week substudy. In the group that received both antioxidants, the increase in plasma Q10 concentration was attenuated. Only vitamin E supplementation increased significantly the oxidation resistance of isolated LDL. Simultaneous Q10 supplementation did not increase this antioxidative effect of vitamin E. Q10 supplementation increased and vitamin E decreased significantly the proportion of ubiquinol of total Q10, an indication of plasma redox status in vivo. The supplementations used did not affect the redox status of plasma ascorbic acid. In conclusion, only vitamin E has antioxidative efficiency at high radical flux ex vivo. Attenuation of the proportion of plasma ubiquinol of total Q10 in the vitamin E group may represent in vivo evidence of the Q10-based regeneration of the tocopheryl radicals. In addition, Q10 might attenuate plasma lipid peroxidation in vivo, since there was an increased proportion of plasma ubiquinol of total Q10.

Factors determining the formation of complexes between alpha-cyclodextrin and alkylated substances in aqueous solutions: a calorimetric study at 25 degrees C.

The formation of complexes of alpha-cyclodextrin with cycloalkanediols, monoalkylamines and 1-alkanols has been studied calorimetrically at 25 degrees C in water, in phosphoric acid, pH 1.3, and in phosphate buffer, pH 5.5, respectively. When a complex is formed, calorimetry enables the calculation of both the enthalpy and the association constant, from which the free energy and the entropy of the process can be obtained. A model is proposed to explain the unusual trend of the association parameters for substances having alkyl chains longer than six-seven carbon atoms. The main role played by the different functional groups, and the forces involved in the association process, are discussed in the light of the signs and values of the thermodynamic parameters obtained. The effect of the variation of the aqueous medium on the hydration of the interacting substances and the consequent changes in the association parameters have been investigated. To this end, the thermodynamic parameters for the formation of the complexes between the cyclodextrin and 1-pentanol were determined at increasing concentrations of phosphate buffer. There is an increase in the association constant due to a positive entropy contribution originating from the relaxation of water molecules from the hydrophobic hydration cosphere of the alkanol to an increasingly disordered bulk. Deaquation of the interacting substances is the main factor determining the stability of the inclusion complex.

1-Benzopyran-4-one antioxidants as aldose reductase inhibitors.

Starting from the inhibitory activity of the flavonoid Quercetin, a series of 4H-1-benzopyran-4-one derivatives was synthesized and tested for inhibition of aldose reductase, an enzyme involved in the appearance of diabetic complications. Some of the compounds obtained display inhibitory activity similar to that of Sorbinil but are more selective than Quercetin and Sorbinil with respect to the closely related enzyme, aldehyde reductase, and also possess antioxidant activity. Remarkably, these compounds possess higher pKa values than carboxylic acids, a characteristic which could make the pharmacokinetics of these compounds very interesting. Molecular modeling investigations on the structures of inhibitors bound at the active site of aldose reductase were performed in order to suggest how these new inhibitors might bind to the enzyme and also to interpret structure-activity relationships.

Prooxidant activity of ferrioxamine in isolated rat hepatocytes and linoleic acid micelles.

The complex iron-desferrioxamine (ferrioxamine) is considered chemically unreactive, and not able to participate in redox cycle reactions. Desferrioxamine-dependent toxicity is, however, described in both human and animal studies. The aim of this work was to test the possibility that chelated iron, under certain circumstances, could enter redox reactions, giving an explanation of desferrioxamine side effects. Carefully prepared ferrioxamine, to obtain a 1:1 desferrioxamine:iron ratio, was added to isolated rat hepatocytes and to linoleic acid micelles. A strong prooxidant and cytotoxic effect was observed in the cells, also potentiating tert-butyl hydroperoxide-induced lipid peroxidation. In micelles, the prooxidant effect was observed only in the presence of ascorbate, which is oxidized during the process, giving rise to ascorbyl radical. Ferrioxamine, under the experimental conditions used, did not release iron, indicating that the prooxidant effect was due to iron redox cycling. The addition of desferrioxamine prevented both ferrioxamine- and tert-butyl hydroperoxide-induced lipid peroxidation and cytotoxicity. Concurrently, a nitroxide radical was detected, an indication of the radical scavenger activity of the hydroxamic moiety. No radical species was observed when ferrioxamine was added to the same system. The prooxidant effect of ferrioxamine gives a possible explanation of the reported human and animal desferrioxamine toxicity. When, in compartmentalized regions, the ratio of desferrioxamine:metal reaches 1:1, ferrioxamine is formed. In the absence of metal-free desferrioxamine, ferrioxamine can participate in redox cycling reactions, initiating lipid peroxidation and cytotoxicity.

Antioxidant activity of carotenoids: an electron-spin resonance study on beta-carotene and lutein interaction with free radicals generated in a chemical system.

beta-Carotene is thought to be a chain-breaking antioxidant, even though we have no information about the mechanism of its antioxidant activity. Using electron-spin resonance (ESR) spectroscopy coupled to the spin-trapping technique, we have studied the effect of beta-carotene and lutein on the radical adducts of the spin-trap PBN (N-t-butyl-alpha-phenylnitrone) generated by the metal-ion breakdown of different tert-butyl hydroperoxide (tBOOH) concentrations in methylene chloride. The peroxyl radical, along with an oxidation product of PBN (the PBNOx), trapped at room temperature from the breakdown of high concentration of tBOOH (1 M), were quenched by beta-carotene or lutein, in competition with the spin-trapping agent. However, carotenoids were not able to quench the alkoxyl and methyl radicals generated in the reaction carried out in the presence of low tBOOH concentration (1 mM). The reaction between carotenoids and the peroxyl radical was also carried out in the absence of the spin trap, at 77 K: Under these different experimental conditions, we did not detect any radical species deriving from carotenoids. In the same system, a further evidence of the peroxyl radical quenching by beta-carotene and lutein was obtained. The antioxidant activity of vitamin E was also tested, for comparison with the carotenoids. In the presence of alpha-tocopherol, peroxyl and alkoxyl radicals were quenched, and the tocopheroxyl radical was detected. Our data provide the first direct evidence that carotenoids quench peroxyl radicals. Under our experimental conditions, we did not detect any carotenoid radical species that could derive from the interaction with the peroxyl radical. The radical-trapping activity of beta-carotene and lutein demonstrated in this chemical reaction contributes to our understanding carotenoid antioxidant action in biological systems.