Widespread abiotic methane in chromitites.

Recurring discoveries of abiotic methane in gas seeps and springs in ophiolites and peridotite massifs worldwide raised the question of where, in which rocks, methane was generated. Answers will impact the theories on life origin related to serpentinization of ultramafic rocks, and the origin of methane on rocky planets. Here we document, through molecular and isotopic analyses of gas liberated by rock crushing, that among the several mafic and ultramafic rocks composing classic ophiolites in Greece, i.e., serpentinite, peridotite, chromitite, gabbro, rodingite and basalt, only chromitites, characterized by high concentrations of chromium and ruthenium, host considerable amounts of 13C-enriched methane, hydrogen and heavier hydrocarbons with inverse isotopic trend, which is typical of abiotic gas origin. Raman analyses are consistent with methane being occluded in widespread microfractures and porous serpentine- or chlorite-filled veins. Chromium and ruthenium may be key metal catalysts for methane production via Sabatier reaction. Chromitites may represent source rocks of abiotic methane on Earth and, potentially, on Mars.

ELISA and LC-MS/MS methods for determining cyanobacterial toxins in blue-green algae food supplements.

The use of natural products as a diet supplement is increasing worldwide but sometimes is not followed by adequate sanitary controls and analyses. Twenty samples of pills and capsules of lyophilised cyanobacteria (blue-green algae), commercialised in Italy as dietary supplements, were found positive at the Vibrio fischeri bioassay. Further analyses with ELISA and LC-MS/MS methods revealed the presence of four microcystin (MC) analogues, MC-LR, -YR, -LA, -RR and two demethylated forms of MC-RR. The highest total microcystin content was 4.5 and 1.4 microg g-1 in pills and capsules, respectively. The ELISA measurements, compared to the LC-MS/MS analyses, showed significantly lower concentrations of microcystins in pills, this confirming a possible ELISA underestimate of mixed microcystins, due to different sensitivities for some toxic analogues.

Fate of natural estrogen conjugates in municipal sewage transport and treatment facilities.

The aim of this study was to investigate the fate of the conjugated forms of the three most common natural estrogens in the municipal aqueous environment. Levels of conjugated and free estrogens in (1) female urine; (2) a septic tank collecting domestic wastewater; (3) influents and effluents of six activated sludge sewage treatment plants (STPs) were measured. The analytical method was based on solid-phase extraction by using a Carbograph 4 cartridge and Liquid Chromatography-tandem Mass Spectrometry. On average, a group of 73 women selected to represent a typical cross section of the female inhabitants of a Roman condominium, excreted 106, 14 and 32 microg/day of conjugated estriol (E(3)), estradiol (E(2)) and estrone (E(1)), respectively. Apart from some E(3) in pregnancy urine, free estrogens were never detected in urine samples. Estrogen sulfates represented 21% of the total conjugated estrogens. This situation changed markedly in the condominium collecting tank. Here, significant amounts of free estrogens were observed and the estrogen sulfate to estrogen glucuronated ratio rose to 55/45. A laboratory biodegradation test confirmed that glucuronated estrogens are readily deconjugated in unmodified domestic wastewater, presumably due to the large amounts of the beta-glucuronidase enzyme produced by fecal bacteria (Escherichia coli). Deconjugation continued in sewer transit. At the STP entrance, free estrogens and sulfated estrogens were the dominant species. The sewage treatment completely removed residues of estrogen glucuronates and with good efficiency (84-97%) the other analytes, but not E(1) (61%) and estrone-3-sulfate (E(1)-3S) (64%). Considering that (1) E(1) has half the estrogenic potency of E(2), (2) the amount of the former species discharged from STPs into the receiving water was more than ten times larger than the latter one and (3) a certain fraction of E(1)-3S could be converted to E(1) in the aquatic environment, E(1) appears to be the most important natural endocrine disrupter.

Method development for measuring trace levels of penicillins in aqueous environmental samples.

A method based on liquid chromatography/mass spectrometry with an electrospray ion source and a single quadrupole instrument (LC/ES-MS) has been developed for determining trace levels of eight widely used penicillins in aqueous environmental samples. Analyte extraction was performed from 4 L tap water, 2 L groundwater, 1 L river water, 0.2 L treated sewage and 0.1 L raw sewage, by using a Carbograph 4 cartridge. During removal of the solvent, penicillins were purposely allowed to convert into their penicilloyl methyl esters. This 'in situ' derivatization step resulted in a dramatic enhancement of the response of the ES-MS system for non-amphoteric penicillins. Analyte recoveries were better than 80% irrespective of the type of aqueous sample, with the exception of amoxicillin (76%) and ampicillin (77%) in tap water. At the level of 50 ng/L of each analyte in ground water, the within-day precision was in the range 6-10%. Calibration curves were linear for injected amounts up to 800 ng, with R(2) in the range 0.9952-0.9995. When injecting large equivalent volumes of the aqueous samples, the electrospray matrix effect altered in-source collision-induced dissociation (CID) spectra of the analytes by severely weakening signals for fragment ions, as compared to spectra of reference standards. Remedies to obviate this anomalous unwelcome effect are suggested. On the basis of a signal-to-noise ratio of 10, limits of quantification were estimated to range between 2 (cloxacillin) and 24 ng/L (amoxicillin) in river water.

Solid-phase extraction followed by liquid chromatography-mass spectrometry for trace determination of beta-lactam antibiotics in bovine milk.

A confirmatory assay able to unambiguously identify and quantify 10 approved-for-use beta-lactam antibiotics in milk below stipulated U.S. and EU tolerance levels is presented. beta-Lactams are extracted from 10 mL of intact milk by a Carbograph 4 cartridge. After solvent removal, residue reconstitution, and filtration, a completely transparent and uncolored extract is injected into a liquid chromatography -mass spectrometry (LC-MS) instrument equipped with an electrospray (ES) ion source and a single quadrupole. During the chromatographic run, the ES/MS system is operated first in the positive-ion mode (PI) and then in the negative-ion (NI) mode. This is done to circumvent matrix interferences resulting in remarkable signal weakening of the last-eluted analytes, when detecting them as [M+H]+ adduct ions. MS data acquisition is performed by a time-scheduled three-ion selected ion monitoring program. At the 5 ng/mL level, recoveries of the beta-lactams are between 70 (nafcillin) and 108% (cephalin), with relative standard deviations ranging between 5 (oxacillin) and 11% (amoxicillin and ceftiofur). The response of the ES/MS detector is linearly related to injected amounts up to 500 ng, irrespective of the chemical characteristics of the beta-lactams and the acquisition mode selected (PI or NI modes). Limits of quantification, based on a minimal value of the signal-to-noise ratio of 10, were estimated to be within 0.4 (cephalin) and 3 ng/mL (dicloxacillin). Analyses of milk samples taken after intramammary application of amoxicillin showed that 1.2 ng/mL of this penicillin was still present 6 days after treatment. At this concentration level, the identification power of the method is not weakened, as signals of the three product ions of amoxicillin are still well distinguishable from the background noise.

Hot phosphate-buffered water extraction coupled on-line with liquid chromatography/mass spectrometry for analyzing contaminants in soil.

We evaluated the feasibility of analyzing rapidly traces of polar and medium polar contaminants in soil by coupling on-line a hot phosphate-buffered water extraction apparatus to a liquid chromatography/mass spectrometer system. Coupling was accomplished by using a small C-18 sorbent trap for collecting analytes and two six-port valves. The efficiency of this device was evaluated by extracting 13 selected pesticides from 200 mg of laboratory-aged soils by varying the extraction temperature, the extractant volume, and the flow rate at which the extractant passed through the extraction cell and the sorbent trap. In terms of extraction efficiency, robustness of the method, and extraction time, the best compromise was that of using 8 mL of extractant at 90 degrees C and 0.5 mL/min flow rate. Under these conditions, recoveries of 11 out of 13 analytes ranged between 82 and 103%, while those of the least hydrophilic pesticides, i.e., neburon and prochloraz, were 73 and 63%, respectively. By increasing the extractant volume to 60 mL, additional amounts of the two latter compounds could be recovered. Under this condition, however, the most hydrophilic analytes were in part no more retained by the C-18 sorbent trap. From a naturally 1.5-year aged soil, hot phosphate-buffered water removed larger amounts of three herbicides and hydroxyterbuthylazine (a terbuthylazine degradation product) than pure water and Soxhlet extraction. This result seems to confirm that hot phosphate buffer is also able to remove from soil those fractions of contaminants that, on aging, are sequestered into the humic acid framework.

Simultaneous determination of acidic and non-acidic pesticides in natural waters by liquid chromatography-mass spectrometry.

There is increasing interest and demand for real multi-residue methods able to simultaneously determine pesticides with a broad spectrum of chemical characteristics in environmental and biological matrices. A method based on solid-phase extraction with a Carbograph 4 cartridge and liquid chromatography with electrospray mass spectrometry (LC-ES-MS) enabling simultaneous determination of non-acidic and acidic pesticides in real water samples is described. On repeatedly (n=5) extracting 4 l of drinking water (spike level 50 ng/l), 2 l of ground water (spike level 100 ng/l) and 1 l of river water (spike level 200 ng/l), recovery of 26 base/neutral pesticides and 13 acidic pesticides were equal to or better than 80%, except for carbendazim (67%), butocarboxim (73%), aldicarb (75%) and molinate (77%). Relative standard deviations ranged between 4 and 15%. Final extracts containing acidic and non-acidic pesticides were analyzed in a single chromatographic run while the ES-MS system was operated in both positive and negative ion modes. With the aim of finding the best operating conditions, in terms of sensitivity, the pH of the LC eluent was varied in the 2.9-8.4 range. Altogether, the best results were obtained by using an LC eluent containing 1 mmol/l formic acid. Over the entire pH range considered, well shaped peaks for both basic and acidic analytes were achieved by the use of a new generation LC column. By extracting selected ion current profiles from the total ion current mass chromatogram relative to analysis of 4 l of drinking water spiked with 50 ng/l of each of the 39 analytes, estimated limits of detection ranged between 0.05 and 1.5 ng/l, except for propyzamide (8 ng/l) and 2,4-DB (3 ng/l).

Multiresidue herbicide analysis in soil: subcritical water extraction with an on-line sorbent trap.

We evaluated the feasibility of extracting selectively and rapidly herbicide residues in soils by hot water and collecting analytes with a Carbograph 4 solid-phase extraction (SPE) cartridge set on-line with the extraction cell. Phenoxy acid herbicides and those nonacidic and acidic herbicides which are often used in combination with phenoxy acids were selected for this study. Five different soil samples were fortified with target compounds at levels of 100 and 10 ng/g (30 ng/g of clopyralid and picloram) by following a procedure able to mimic weathered soils. Herbicides were extracted with water at 90 °C and collected on-line by the SPE cartridge. After the cartridge was disconnected from the extraction apparatus, analytes were recovered by stepwise elution to separate nonacidic herbicides from acidic ones. The two final extracts were analyzed by liquid chromatography/mass spectrometry with an electrospray ion source. At the lowest spike level considered, analyte recoveries ranged between 81 and 93%, except those for 2,4-DB and MCPB, which were 63%. For 16 herbicides out of 18, the ANOVA test showed recoveries were not dependent on the type of soil. The method detection limit was in the 1.7-10 ng/g range. For the analytes considered, method comparison showed this extraction method was overall more efficient than Soxhlet and sonication extraction techniques.

Defibrotide as a possible anti-ischemic drug.

Defibrotide is a polydeoxyribonucleotide extracted from mammalian organs (porcine) and prepared by controlled depolymerization, resulting in a single-stranded deoxyribonucleotide with a mean molecular weight of 15 to 30 kDa. Early studies of experimental pharmacology in different animal species (1981-1986) were focused on an antithrombotic effect in arteries, veins, and the microcirculation, attributed to a dose-dependent activation of fibrinolysis. More recently, a number of new data have raised interest in an "anti-ischemic" action of the substance, as suggested by its evident protective effect in different models of tissue and organ ischemia. Protection from myocardial ischemia was demonstrated in different experimental models, and several ischemic features, such as heart muscle contracture, loss of high-energy substrates, decline in beta-adrenergic receptor sensitivity, and drop in infarct-related blood flow, were successfully prevented. Similar protective effects were observed during liver and kidney ischemia and in different types of experimental shock. The mechanisms involved in the anti-ischemic properties of defibrotide have been investigated in studies of experimental and human pharmacology. The substance has been shown to modulate arachidonic acid metabolism by enhancing the production and release of prostacyclin and prostaglandin E2 from tissues and whole blood, and inhibiting leukotriene B4 generation in leukocytes. Furthermore, an effect of defibrotide on activation of polymorphonuclear leukocytes and their incorporation into thrombi was described. Favorable effects on blood rheology were also reported. In summary, defibrotide deserves attention for therapeutic trials in clinical conditions characterized by organ or tissue ischemia.

Plasma levels of the molecular markers of coagulation and fibrinolysis in patients with peripheral arterial disease.

In 103 patients with peripheral arterial disease (PAD) of the lower limbs, coagulation and fibrinolytic parameters were evaluated to identify hemostatic abnormalities characteristic of this patient population. PAD was defined as clinically stable Leriche stage 2 (based on clinical history, peripheral pulses, ankle-arm index, and treadmill test) for at least 3 months, walking distance > 100 m, and no other major illnesses, rest pain, or trophic lesions. Defibrotide, a polydeoxyribonucleotide derivative with vascular effects, was administered to the patients as part of a multicenter trial. The PAD patients exhibited a prothrombotic state as evidenced by high D-dimer in all but 24% of the patients (average 797 +/- 802 vs. 163 +/- 54 ng/mL normal population; p < 0.001) and high thrombin-antithrombin III complex (TAT) levels (10.2 +/- 8.9 vs. 2.5 + 1.5 ng/mL; p < 0.001) with low to normal levels of protein C (86 +/- 25 vs. 102 +/- 18%; p < 0.01) and plasminogen activator inhibitor-1 (PAI-1) antigen (5.9 +/- 4.5 vs. 1.3 + 0.7 ng/mL; p < 0.001) were elevated in 79% of the patients. These results suggest that there is ongoing thrombosis in the majority of PAD patients. Differences from normal controls were observed for t-PA, PAI-1, protein C, and protein S; however, it is not certain that the thrombosis in patients with PAD is due to these factors.

Effects of defibrotide on physical performance and hemorheologic picture in patients with peripheral arteriopathy.

In a random double-blind study versus placebo, 60 ambulatory patients with peripheral occlusive disease of the lower limbs and claudicatio intermittens (Leriche's stage 2), were treated for 60 days with defibrotide (400 mg b.i.d., oral, n = 30) or placebo (n = 30). Patients in the defibrotide group received additional treatment with the same drug at the reduced rate of 400 mg once daily for another 120 days for maintenance (total treatment duration 180 days). All patients were assessed at intake and 60 days for relative and absolute walking distance (RWD and AWD) in a standard treadmill test and for the Winsor Index (WI) at rest and after exercise; patients of the defibrotide treatment group were retested in the same way at 90-180 days. In a subgroup of patients (defibrotide = 11, placebo = 12), blood samples were obtained for the assessment of whole blood and plasma viscosity at intake and after 60 days of treatment. These samples could not be collected properly in the remaining cases, for technical reasons. At day 60, we compared the effects of the two treatments on physical performance: mean (SE) values of RWD were for defibrotide 148 (9.7) and 179 (12.4) m in basal and post-treatment conditions, respectively, and 209 (16.2) and 212 (17.1) m for placebo. Similar changes were observed for AWD: for defibrotide 206 (13.4) and 241 (15.2) m and for placebo 270 (22.9) and 272 (23.1) m. The mean changes were significantly larger with defibrotide: for RWD + 33 (7.1) vs. + 0.3 (3.8) m (p < 0.01) and for AWD + 34 (9.2) and -2 (6.6) m (p < 0.01). The overall gain of walking distance after maintenance therapy with the reduced defibrotide dosage amounted to approximately + 50% over basal (after 180 days). Blood and plasma viscosity improved in patients on defibrotide but the change fell short of statistical significance versus placebo. All findings confirm the potential usefulness of defibrotide in the treatment of peripheral arterial disease, at the same time encouraging further studies of the involved mechanisms of action.

Hemodialysis with defibrotide: effects on coagulation parameters.

In a crossover study conducted with eight uremic patients maintained on hemodialysis, the Authors compared the effects of heparin (100 IU/kg at the start of dialysis) and defibrotide (400 mg at the start, repeated at 2 hours of ongoing dialysis) on the parameters of blood coagulation (VIII:C, AT III, TAT, PC antigen and activity, PS, and FPA), each being assessed before dialysis and at 2, 3 and 4 hours of the ongoing procedure. Heparin-assisted dialysis resulted in a significant rise of VIII:C and AT III; with defibrotide, instead, there was evidence of thrombin activation (increased FPA and TAT). PC levels were raised with both dialysis modalities; however, PC activity and PS levels were increased only in defibrotide-assisted dialysis. There were no adverse reactions or evidence of fibrin formation. These results confirm the antithrombotic activity of defibrotide in the course of dialysis and indicate that this action is independent of thrombin neutralization.

Effect of sulglycotide treatment on cell kinetics alterations induced by aspirin in humans.

The effect on gastric epithelial cell proliferation of small doses of aspirin was evaluated in 9 healthy volunteers, with or without administration of sulglycotide, a sulfated glycopeptide with cytoprotective properties. Cell kinetics study was performed by incubation of gastric biopsies with bromodeoxyuridine (BrdU) and immunohistochemistry. A decrease of BrdU-labeling index and a shortening of the height of gastric columns were observed after treatment with aspirin and placebo. No variations were observed after treatment with aspirin and sulglycotide. A decrease of the epithelial cell renewal could be one of the damaging effects of aspirin on the gastric mucosa. The treatment with sulglycotide seems to be effective to prevent this alteration.

[The prevention of deep venous thrombosis in patients undergoing an internal arteriovenous fistula intervention]. / Prevenzione di TVP in pazienti sottoposti ad intervento di fistola-arterovenosa interna.

Twenty patients, submitted to internal arteriovenous fistula procedure, were randomly assigned to one of the following treatments: defibrotide 400 mg b.i.d. IM (starting the day before surgery and continuing for the following 7 days); calcium heparin 5,000 IU t.i.d. SC (since the day of surgery and for the following 7 days). No deep venous thrombosis or thrombosis of the fistula were noticed during both treatments and no side effects were observed. In the defibrotide group, ELT showed a significant decrease (-40%) attesting an improvement of fibrinolysis without a plasminogen abatement. These findings indicate that defibrotide represent an effective alternative to calcium heparin for antithrombotic prophylaxis of A-V fistula in uremic patients.

Deficient fibrinolytic response in patients with Raynaud's phenomenon and its correction with defibrotide.

Twenty outpatients presenting with Raynaud's phenomenon secondary to clinical or preclinical inflammation of connective tissue were treated orally with defibrotide 400 mg three times daily or a matching placebo in a randomized double-blind study. The test product defibrotide (a polydeoxyribonucleic acid compound of animal origin with demonstrated profibrinolytic activity when administered parenterally) was administered orally for 3 weeks in order to explore its effects on the parameters of extrinsic fibrinolysis before and after venous stasis. The antigen of t-PA and its inhibitor PAI, free and total, and the biologic activity of PAI were assayed in basal conditions and after treatment. Although a marked increase of t-PA was seen with the active treatment, PAI activity was significantly reduced by defibrotide. Immunoreactive PAI was not significantly modified by treatment, even though it dropped considerably after venous stasis in the defibrotide group. Thus, the disturbance of endothelial function that seems to occur in vasculitis and in Raynaud's phenomenon secondary to inflammation of connective tissue (or so suspected to be) would constitute the basis of a disturbance of fibrinolysis, which oral defibrotide seems able to correct. Further studies are warranted to define the clinical effectiveness of this treatment in patients with Raynaud's phenomenon.

A multicenter double-blind study of sulglycotide versus sucralfate in nonulcer dyspepsia.

Nonulcer dyspepsia remains to this date a clinical disease entity that is diagnosed and treated empirically by considering such patients potential ulcer carriers and treating them accordingly with H2 antagonists. The purpose of this study was to assess the therapeutic effectiveness of sulglycotide in patients with nonulcer dyspepsia in a random double-blind trial vs sucralfate. One hundred and eighty-seven consecutive patients with nonulcer dyspepsia were treated with sulglycotide (oral, 200 mg t.i.d. for 6 weeks, n = 93) or with sucralfate (oral, 1 g t.i.d. for the same length of time, n = 94). Drug effectiveness was evaluated in terms of apparent clinical symptom modifications, fiberoptic endoscopy findings and histological aspects of biopsy specimens. Both treatments resulted in prompt abatement of the clinical complaints of nonulcer dyspepsia and the improvement of macroscopic gastritis at endoscopy. These results confirm the usefulness of cytoprotective drugs in nonulcer dyspepsia characterized by gastroduodenal inflammation.

Kinetics of anti-Xa activity during combined defibrotide-heparin administration in hemodialysis.

Defibrotide, a polydesoxyribonucleotide derivative with antithrombotic and fibrinolytic activity, capable of inducing the release of PGI2 from vascular endothelia, was proposed as an alternative to standard heparin coverage during blood dialysis for patients at risk of bleeding. The original procedure featured the preliminary washing of the dialysis circuit with heparin, which was then recirculated and eliminated, and the two drugs, heparin and defibrotide, are known to interact with each other. The purpose of this present study was to explore the ex-vivo heparin activity (assessed as anti-Xa activity) in diverse hemodialysis models using defibrotide (800 mg intravenous, in 4 bolus injections) and various dosages of heparin. Anti-Xa activity is negligible in dialysis conducted with defibrotide alone. When the circuit was prewashed with heparin (5000 and 2500 IU), there was evident anti-Xa activity (0.3-0.5 U/ml) in the first 30-60 minutes of dialysis; continuous heparin infusion (500 U/hour) resulted in high anti-Xa activity levels at the end of dialysis. Thus the best hemodialysis procedure for patients at high risk of bleeding should be one utilizing only defibrotide, or defibrotide plus small amounts of calcium heparin infused at the rate of 500 U/hour for not more than two hours.

[A multicenter study of defibrotide in the prevention of deep venous thrombosis. Final results]. / Studio multicentrico con defibrotide nella profilassi delle trombosi venose profonde. Risultati finali.

In an open multicenter comparative study aimed at the evaluation of the efficacy of defibrotide and calcium heparin in the prophylaxis of postoperative deep vein thrombosis (DVT) and pulmonary embolism (PE) an evaluation has been made on 4810 patients. 2810 patients received defibrotide (800 mg/die: 400 mg b.i.d. or 200 mg q.i.d. by IV route); 2000 patients received calcium heparin (500 IU b.i.d. or t.i.d. by SC route) till the 7th post-operative day. The diagnosis of DVT or pulmonary embolism (PE) was made according to clinical routine criteria. The incidence of DVT has been 33/2810 (1.17%) in the defibrotide group and 47/2000 (2.35%) in the heparin group (chi 2 p = 0.002), while the cases of suspected or ascertained PE have been respectively 15/2810 (0.53%) and 23/2000 (1.15%) (p = 0.025). The post-operative course was totally normal in both groups; no significant adverse reactions were noticed. The obtained results suggest the effectiveness of defibrotide as an alternative to heparin in the prevention of post-operative DVT.

[Sulglicotide in the prevention of gastric disease induced by NSAID. Double-blind controlled study versus placebo]. / Sulglicotide nella prevenzione della gastropatia da FANS. Studio controllato in doppio cieco vs placebo.

Non-steroidal anti-inflammatory drugs, essential for the treatment of rheumatic diseases, are frequently associated with significant adverse effects on the integrity of the gastrointestinal mucosa. Sulglicotide (S), a natural product, has been found to possess gastromucosal protective properties. Aim of the present study was to evaluate whether (S) 200 mg t.i.d prevented or reduced the severity of gastric and/or duodenal mucosal injury induced by Diclofenac. A total of 30 patients with either rheumatoid arthritis (RA) or osteoarthritis (OA) who required NSAID therapy for at least 8 weeks were enrolled into a double-blind randomized placebo-controlled study. The main criteria for entry into the trial was the absence of gastrointestinal symptoms, and gastric/duodenal lesions assessed by endoscopy. At the end of the treatment endoscopy and relative symptoms were assessed. Six out of 15 patients, in both groups of treatment developed mucosal injury, but only in the placebo group the gastric damage was important (ulcer and petechiae) while in the group (S) we observed only hyperemia of the gastric mucosa. These preliminary data indicate the usefulness of Sulglicotide in preventing or reducing mucosal injury from NSAID treatment.