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S Paglialunga

Publications and source records attributed to S Paglialunga.

At least 19 recordsLinked to original sources

Increased levels of acylation-stimulating protein in interleukin-6-deficient (IL-6(-/-)) mice.

IL-6-deficient (IL-6(-/-)) mice develop obesity at 6-7 months of age. To elucidate the mechanisms of this mature-onset obesity, global gene expression profiles of 3-month-old preobese IL-6(-/-) were compared with those of IL-6(+/+) mice using DNA arrays. Genes that were up-regulated in IL-6(-/-) mice included the factors transthyretin and properdin in white adipose tissue and adipsin in muscle. These factors have been shown to influence the formation of acylation-stimulating protein (ASP), a cleavage product of complement C3. ASP stimulates the synthesis of triacylglycerol in adipocytes, and ASP-deficient mice are resistant to diet-induced obesity. In line with the increases in transthyretin, properdin, and adipsin, ASP levels in serum were increased by 31-54% in IL-6(-/-) compared with IL-6(+/+) mice. Furthermore, IL-6 replacement treatment in IL-6(-/-) mice decreased ASP levels significantly by 25-60%. In conclusion, ASP levels are increased in preobese IL-6(-/-) mice. This increase may result in increased triacylglycerol formation and uptake in IL-6(-/-) adipocytes and thereby contribute to the development of obesity in IL-6(-/-) mice.

Adipocytes↗

[Echo-Doppler in chronic kidney transplant rejection. The diagnostic prospects using indices of the ascending systolic phase].

To date, Doppler US has been rarely used to diagnose chronic renal transplant rejection because of its low sensitivity. Nevertheless, all the results have been obtained from the analysis of flow-metric indices, mainly considering the diastolic phase of the Doppler waveform, e.g., the resistance index (RI) and the pulsatility index (PI). This study was aimed at investigating if Doppler diagnostic accuracy in renal transplant monitoring can be increased by studying the systolic phase, considering peak arterial systolic velocity (Vp), acceleration time (AT) and acceleration index (AI). Seventy-six renal transplant recipients were examined with color-Doppler and duplex Doppler US, which showed 47 well-functioning and 29 hypofunctioning kidneys. The diagnosis was confirmed with perfusion scintigraphy with 99mTc DTPA, biopsy and 6-month clinical-laboratory follow-up. The means of Vp, AI, AT and RI relative to the group of patients with normal renal function were compared with those in the group of patients with chronic rejection. Critical values were measured at the segmental arteries (Vp = 70 cm/s, AI = 7 m/s2, AT = 100 ms), at the interlobar arteries (Vp = 45 cm/s, AI = 4 m/s2, AT = 100 ms) and at the arcuate arteries (Vp = 35 cm/s, AI = 3 m/s2, AT = 100 ms). On the basis of these values, normal functioning transplants were differentiated from hypofunctioning ones. RIs were altered (> 0.75) in 8 of 17 chronic rejections and in 3 of 47 normal transplants, with 47.1% sensitivity and 93.6% specificity. The combination of RI with Vp and AI strongly increased both sensitivity (100%) and specificity (82.98%). Combined AI and RI exhibited 94.1% sensitivity and 89.3% specificity. In conclusion, the indices of the ascending systolic phase, in peripheral vascular samplings, are clearly more efficacious than RI alone and index combination exhibits the highest diagnostic accuracy.

Adult↗

Induction of micronuclei in Vicia faba root tips treated with heavy metals (cadmium and chromium) in the presence of NTA.

Soluble metal compounds (CdCl2, K2Cr2O7) significantly increase the frequency of micronucleated cells in Vicia faba root tips with a clear dose-effect relationship. The addition of NTA (nitrilotriacetic acid) does not enhance the induction of micronucleated cells. Conversely, insoluble metal compounds (CdCO3, PbCRO4) significantly enhance the frequency of micronucleated cells only in the presence of NTA. Since some genotoxic metals are diffused in the environment and are often sequestered as insoluble precipitates in water sediments and sludges, the introduction of NTA is likely to increase the risk of environmental pollution because of its ability to solubilize and make those metals reactive.

Acetates↗

Mammalian cell transformation induced by chromium(VI) compounds in the presence of nitrilotriacetic acid.

We used a soft agar assay on cultured Syrian hamster fibroblasts to determine the ability of nitrilotriacetic acid (NTA) and Cr(VI) compounds to induce malignant cell transformation. Induction of extended anchorage-independent growth was detected in BHK 21/c13 cells by scoring colonies of transformed cells visible to the naked eye 20-25 d after plating in growth medium containing agar. Survival was determined by plating cells in liquid medium without agar and by counting the number of macroscopic colonies after 7-10 d. Mitomycin C and 4-nitroquinoline 1-oxide were used as reference direct transforming agents, with clearly positive results. In our hands no increase of the spontaneous transformation rate of BHK cells was induced by NTA concentrations ranging from 2 X 10(-3) to 10(-2) M, although the survival index was significantly reduced above 4 X 10(-3) M NTA. Two Cr(VI) compounds, K2Cr2O7, which is highly soluble in water, and CaCrO4, which is partially soluble, were tested in the soft agar assay either in the absence or in the presence of NTA. When used alone, both compounds behaved as positive transforming agents. NTA increased 4 or 10 times the cytotoxicity and the transforming activity of CaCrO4 and K2Cr2O7, respectively. As the amounts of soluble Cr(VI) detectable in the K2Cr2O7 and CaCrO4 solutions were not increased in the presence of NTA, a synergistic interaction between NTA and soluble Cr(VI) is inferred.

Acetates↗

Solubilization by nitrilotriacetic acid (NTA) of genetically active Cr(VI) and Pb(II) from insoluble metal compounds.

The frequencies of sister chromatid exchanges (SCE) were significantly increased in cultured Chinese hamster cells by insoluble salts of Cr(VI) (PbCrO4) and Pb(II) (PbSO4). A further significant increase of this effect was produced when diluted suspensions of PbCrO4 (1-4 mg/l) and PbSO4 (10-40 mg/l) were preincubated with nitrilotriacetic acid (NTA) concentrations (0.25-1 mg/l) such as those that are possibly found in highly contaminated environmental situations. NTA enhanced the induction of SCE by PbCrO4 and PbSO4 even in the presence, in the preincubation solution and in the medium used to treat the cells, of Na+ and K+ concentrations largely exceeding (e.g., 10(2)-10(6) times) those of the genotoxic metals.

Acetates↗

Increased mutagenicity of chromium compounds by nitrilotriacetic acid.

Nitrilotriacetic acid trisodium salt (NTA), which is a substitute for polyphosphates in household laundry detergents, and N-nitrosoiminodiacetic acid (NIDA), a derivative of NTA produced by metabolism of soil microorganisms, were tested for in vitro mutagenicity in bacteria and yeasts. No gene reversions in five strains of Salmonella typhimurium (TA 1535, TA1537, TA1538, TA98, and TA100), no forward gene mutations in Schizosaccharomyces pombe P1, and no mitotic gene conversions at two loci in Saccharomyces cerevisiae D4 were induced by NTA (up to 870 micrograms/plate or 40 micrograms/ml) and NIDA (up to 2,000 micrograms/plate or 1,000 micrograms/ml), independently of the presence of rat liver metabolic activation. The influence of NTA on the mutagenic and clastogenic activity of several chromium compounds was examined in the Salmonella/microsome assay and in the sister chromatid exchange (SCE) assay in mammalian cell cultures (Chinese hamster ovary [CHO] line). NTA does not affect the genetic inactivity of water-soluble Cr(III) (Cr2[SO4]3) and the direct mutagenicity of soluble Cr(VI) (Na2CrO4,K2Cr2O7) compounds. The very insoluble Cr(VI) compounds PbCrO4 and PbCrO4 X PbO are instead clearly mutagenic in the Salmonella/microsome assay (TA100 strain) only in the presence of NTA or NaOH. The mutagenicity of lead chromates is correlated with the amounts of Cr(VI) solubilized by NTA or alkali, as detected by the colorimetric reaction with diphenylcarbazide and atomic absorption spectrophotometry. In the SCE assay, the insoluble lead chromates are directly clastogenic owing to prolonged treatment conditions and cellular endocytosis. The chromosome-damaging activity of PbCrO4 is significantly increased by NTA but not by NaOH.

Acetates↗

Interaction of nitrilotriacetic acid with heavy metals in the induction of sister chromatid exchanges in cultured mammalian cells.

The ability of nitrilotriacetic acid trisodium salt (NTA) to induce sister chromatid exchanges (SCE) and to influence the induction of SCE by heavy metal compounds was evaluated with mammalian cell cultures. In accordance with the generally negative results obtained by other investigators on the mutagenic effects of NTA, no increase of SCE frequency was observed in Chinese hamster cells (CHO line) or in primary cultures of mouse (BALB/c and BALB/Mo strains) lymphocytes, after treatment with NTA at subtoxic concentrations (2 X 10(-3) M and 10(-3) M, respectively). The induction of SCE by salts of heavy metals (Cd, Hg, Ni, Pb) was evaluated with CHO cells. Soluble (CdCl2, HgCl2, NiCl2, Pb [CH3COO]2) and insoluble (CdCO3, HgCl, NiCO3, PbSO4) compounds were tested, and, with the exception of Pb(CH3COO)2, all were found to increase the frequency of SCE. NTA apparently did not affect the ability of the soluble metal compounds to induce SCE, but it significantly increased the frequency of SCE induced by treatment with all the insoluble salts.

Acetates↗

Effects of nitrilotriacetic acid on the induction of gene mutations and sister-chromatid exchanges by insoluble chromium compounds.

The influence of nitrilotriacetic acid trisodium salt (NTA) on the mutagenic and clastogenic activity of several water-insoluble or poorly soluble chromium compounds was determined by means of the Salmonella/microsome assay (plate test on TA100 strain) and the sister-chromatid exchange (SCE) test in mammalian cell cultures (CHO line). NTA in itself did not induce gene mutations nor did it increase the frequency of SCE. Cr(VI) compounds (Pb, Ba, Zn, Sr and Ca chromates) and an industrial Cr(VI) pigment, chromium orange (containing PbCrO4 PbO), were inactive or scarcely active mutagens in the Salmonella/microsome test when dissolved in water, but they were increasingly mutagenic when solubilized by 0.5 N NaOH or NTA (10 or 100 mg/ml). Also, the mutagenic activity of Cr(VI), contaminating an industrial Cr(III) pigment (chromite), was slightly enhanced by NTA. Mutagenicity of chromates was correlated with the amounts of Cr(VI) solubilized by NTA or alkali, as determined by the colorimetric reaction with diphenylcarbazide and atomic absorption spectrophotometry, and was decreased by incubation with microsomes, due to reduction of Cr(VI) to the genetically inactive Cr(III) form. In the SCE assay, the insoluble or poorly soluble Ba, Zn, Sr and Ca chromates and the insoluble Cr(VI) pigments zinc yellow (containing ZnCrO4 Zn(OH2], chromium yellow and molybdenum orange (both containing PbCrO4) were directly clastogenic due to cellular endocytosis taking place in prolonged treatments, and NTA significantly increased their chromosome-damaging activity.

Acetates↗

Transfer RNA methylase activity and capacity during aflatoxin B1-induced hepatocellular carcinogenesis.

Transfer RNA methylase (tRNA methylase) activity and capacity were monitored in whole-rat-liver preparations during the induction of hepatocellular carcinomas by an 8-week aflatoxin B1 dosing regimen that produced minimal toxic effects. Significant phases of elevated tRNA methylase capacity occurred at 6 to 9 weeks (20%) and 24 to 29 weeks (40%). No significant change in tRNA methylase activity was noted over the course of the 55-week experiment. Higher aflatoxin B1 doses, producing acute toxic liver damage, resulted in elevated tRNA methylase activity (50%) and capacity (30%) at least as early as 1 week after dosing. Experiments with individual nodular lesions excised from livers of rats continuously fed a diet containing 2 ppm aflatoxin B1 demonstrated similarly elevated tRNA methylase activities and capacities in hyperplastic (preneoplastic)nodules, with and without histological evidence of carcinoma.

Aflatoxins↗

Carcinogenicity of nitrosation products of ephedrine, sarcosine, folic acid, and creatinine.

Carcinogenic activity of several synthetic N-nitroso compounds was evaluated in C57BL/6J X C3HeB/FeJ F1 mice. Test substances, suspended in trioctanoin, were injected i.p. in three equal doses given on Days 1, 4, and 7 after birth and animals were held without further treatment for up to 85 weeks. Nitrosoephedrine at a total dose of 600 mg/kg induced metastasizing liver cell carcinomas in 28 of 30 animals. Nitrososarcosine (225 mg/kg) induced similar tumors in 8 of 14 animals. Nitrosofolic acid (375 mg/kg) induced lung adenocarcinomas in 4 of 28 mice. Creatinine-5-oxime (600 mg/kg) showed no evidence of carcinogenic activity. Diethylnitrosamine (12 mg/kg given in four doses), included as a positive control, caused metastasizing liver cell tumors in 23 of 25 animals.

Adenoma, Bile Duct↗