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A new HPLC method with fluorescence detection using pyridinium hydrobromide perbromide as a post-column derivatising agent has been developed to determine aflatoxin M1 in milk and cheese. The detection limits were 1 ng/kg for milk and 5 ng/kg for cheese. The calibration curve was linear from 0.001 to 0.1 ng injected. The method includes a preliminary C18-SPE clean-up and the average recoveries of Aflatoxin M1 from milk and cheese, spiked at levels of 25-75 ng/kg and 100-300 ng/kg, respectively, were 90 and 76%; the precision (RSDr) ranged from 1.7 to 2.6% for milk and from 3.5 to 6.5% for cheese. The method is rapid, easily automatable and therefore useful for accurate and precise screening of aflatoxin M1 in milk and cheese.

More than 65 million Americans are currently obese. Type 2 diabetes mellitus, frequently seen in obese subjects, affects 17 million adults in the United States, with a continuous and alarmingly increasing rate. To prevent development of diabetes in those who are at high risk, it is recommended to optimize meal planning and enhance physical activity to make sustained weight reduction possible. In addition to lifestyle changes, various oral antidiabetic agents are available, with diverse mechanisms of action. Some target defective insulin secretion (sulphonylureas, benzoic acid derivatives) or glucose absorption (glycosidase inhibitors), whereas others target insulin resistance (metformin, thiazolidinediones). Patients with metabolic syndrome and diabetes have an increased risk for cardiovascular disease linked to a higher prevalence of hypertension, dyslipidemia, microalbuminuria, and altered hemostasis--parameters that may be modified by antidiabetic agents. In this article, we review the oral agents used to treat type 2 diabetes and the metabolic syndrome, and their effects on vascular tissue.

The work reports the main results of an experimental activity aimed at evaluating the performance of a membrane bioreactor with complete sludge retention and the characteristics of its biomass. The bench scale system was started-up without any sludge inoculum and fed on real municipal sewage in order to favour biomass selection based on the imposed operating conditions. Process performance was evaluated in terms of COD removal (above 90% on average) and nitrification under two pre-determined volumetric loading rates (0.8 and 1.7 gCOD L(react)(-1), d(-1) on average). The biomass was evaluated in terms of growth, accumulation of inert solids, and bacterial activity. The latter was measured through respirometric tests. The results showed that the suspended solids concentrations (SS) under equilibrium were proportional to the volumetric loading rates in both the experimental periods considered and a relationship between these two parameters was proposed. Also, the organic loading rates reached the same equilibrium value of 0.12 gCOD gTSS(-1) d(-1) in the two periods. Moreover, the system showed very limited sludge production under equilibrium conditions (0.12 gVSS gCOD(rem)(-1) and low biomass activity, although it readily responded to load variations.

The feasibility of using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) for determining 8 fungicides (triadimenol, penconazole, propiconazole, hexaconazole, cyproconazole, myclobutanil, fenarimol, and bitertanol) in extracts of tomato puree and lemon juice concentrate has been evaluated. A miniaturized extraction-partition procedure requiring small amounts of nonchlorinated solvents has been used. The extracts (5 microL) were analyzed by LC/ESI-MS/MS without any previous cleanup step. Chromatographic determination has been performed using a C18 column and isocratic elution. Seventeen MS/MS transitions of precursor ions were monitored simultaneously (2 or 3 for each pesticide). The excellent selectivity and good linearity of the LC/MS/MS method allowed quantitation and identification at low levels (limits of quantitation <0.010 mg/kg), even in difficult matrixes, with a run time of only 1.5 min.

Results are reported concerning a 2-year field investigation on municipal wastewater reclamation for the irrigation of two experimental crops: tomato and fennel. Throughout the investigation, approximately 500 m(3) of tertiary membrane filtered wastewater without further disinfection was supplied to one of two parcels (500 m(2) each) of a test field located in Southern Italy. The second parcel was comparatively irrigated with 500 m(3) of conventional well water. Objectives of the investigation were (i) the evaluation of the performance of a membrane filtration pilot plant (productivity=0.7 m(3)h(-1)) for tertiary treatment and (ii) the comparison between agronomic results (features of soil and crops) after irrigation with reclaimed wastewater versus conventional groundwater. Over long term operation, the pilot plant performance resulted very good in terms of suspended solids and bacterial removal. Referring to the agronomic results, no substantial differences were observed after 2 years, both in terms of microbiological quality of the crops and characteristics of the soil. The whole results indicate membrane filtered municipal effluent as a viable alternative water resource for irrigation.

This paper describes a method for the sensitive and selective determination of 24 new pesticide residues (azoxystrobin, trifloxystrobin, kresoxim-methyl, fenazaquin, indoxacarb, fenothiocarb, furathiocarb, benfuracarb, imidachloprid, dimethomorph, fenpyroximate, hexythiazox, tebufenpyrad, tebufenozide, difeconazole, fenbuconazole, flusilazole, paclobutrazol, tebuconazole, tetraconazole, bromuconazole, etofenprox, fenhexamid, pyridaben) in apple puree, concentrated lemon juice and tomato puree. A miniaturized extraction-partition procedure requiring small amounts of non-chlorinated solvents was used. The extracts are analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) without any further clean-up step. The pesticides are separated on a reversed-phase polar column using a gradient elution. Fifty-five simultaneous MS-MS transitions of precursor ions were monitored (two or three for each pesticide). Studies at fortification levels of 0.001-0.020 and 0.010-0.200 mg/kg gave mean recoveries ranging from 76 to 106% for all compounds, except for imidacloprid, with (R.S.D.s) < or = 15%. The excellent sensitivity and selectivity of LC-MS-MS method allowed quantitation and identification at low levels also in difficult matrices with a run time of 20 min. With the developed method almost 100 samples of commercial fruit products (nectars, juices, purees) were analyzed. None of samples contained residues higher than 0.010 mg/kg.

A new method to measure the leg stiffness in hopping and bouncing, with simple technical equipment and under field conditions, is introduced and validated. The leg stiffness (K (N)) was calculated from only contact and flight times measured by a contact mat. It was compared to the reference stiffness (K (R)) obtained from force platform measurements. Eight subjects performed, first, submaximal hopping movements at different frequencies (1.8 to 4 Hz, by step 0.2 Hz) and, second, maximal hopping. In sub maximal hopping K (N) was significantly correlated with K (R) (r = 0.94; p < 0.001) and the difference between K (N) and K (R) ranged from -7.2 % to 6.9 % (at 1.8 and 3.6 Hz respectively) with a limit of agreement of -1.5 kN x m (-1). In maximal hopping K (N) was also related to K (R) (r = 0.98, p < 0.001) and the inter individual rank order was respected (R = 0.87). It was concluded that the new method could be applied to study extensively intra individual and inter individual variations of leg stiffness in respectively sub maximal and maximal hopping and thus to simplify further investigations in field conditions of the role of stiffness regulation in the optimization of human locomotion.

This work reports the main results of a bench scale membrane bioreactor operated for more than 100 days without sludge withdrawal and fed on real municipal wastewater. The experiments were oriented towards three main objectives. Firstly, the performance of the system was evaluated under two different volumetric loading rates (0.8 and 1.7 g CODL(react.)(-1)d(-1)). Secondly, biomass growth and accumulation of solids were assessed and a relationship between sludge concentration and volumetric loading rates was proposed. Thirdly, biomass activity was evaluated through respirometric tests, and endogenous and maximum respiration rates of heterotrophic and nitrifying bacteria were determined. The experimental campaign showed that these systems are easy to manage and very rapid to start-up. The SS concentrations under equilibrium conditions for both experimental periods were slightly lower than 10 times the volumetric loading rates, and the organic loading rates reached the same equilibrium value of 0.12 g CODgTSS(-1)d(-1). Furthermore, under equilibrium conditions the system showed very limited sludge production (0.12 g VSSgCOD(rem)(-1)) and low biomass activity, although it readily responded to load variations. Further work is being carried out to evaluate the performance over the long term.

A gas chromatographic method was developed for the simultaneous determination of 12 pyrethroids (tefluthrin, bifenthrin, fenpropathrin, cyhalothrin, permethrin, cyfluthrin, cypermethrin, alpha-cypermethrin, flucythrinate, fenvalerate, fluvalinate, and deltamethrin) in tomato puree, peach nectar, orange juice, and canned peas. A miniaturized extraction-partition procedure requiring small amounts of nonchlorinated solvents is used. Samples are extracted with acetone, partitioned with ethyl acetate-cyclohexane (50 + 50, v/v), and cleaned up on a Florisil cartridge. The final extract is analyzed by gas chromatography with both electron capture and mass spectrometric detection modes. Studies at fortification levels of 0.010-0.100 mg/kg gave mean recoveries ranging from 70.2 to 96.0% and coefficients of variation between 4.0 and 13.9% for all compounds. Quantitation limits were < 0.010 mg/kg for electron capture detection.

The existence of a series of triatomic molecules with the general formula MNM', where M is an alkaline metal (K, Rb, Cs), and M' is an alkaline earth metal (Ca, Sr, Ba), has been predicted by quantum chemical methods. Among these, the CsNBa molecule shows a feature not found before, the presence of a multiple bond between barium and nitrogen. As a consequence of this novel bonding situation, the molecule is linear. The same holds for all Ba triatomics, MNBa, independent of the nature of the alkali M atom, and for all Sr compounds, MNSr. The presence of a multiple bond makes CsNBa, and other related Ba and Sr molecules, particularly stable and appealing experimentally. The systems with the alkaline earth metal M' = Ca, on the other hand, turned out to be bent. Calculations have also been performed on the negative ions BaN(-) and CaN(-), which form a well-defined entity in the MNM' systems (M' = Ba, Ca). The results show that the two ions have a different electronic structure in the ground state, which is one reason for the different properties of the MNM' systems and explains why the molecules containing the BaN(-) moiety are linear, while those containing CaN(-) are bent.

Rationale: Several lines of evidence have indicated that the central histaminergic system might be involved in learning and memory, Objectives: The aim of the present study was to ascertain the impact on memory processes of putative histaminergic-cholinergic interactions in the nucleus basalis magnocellularis (NBM) of the rat., Methods: The effects of thioperamide, a histamine H3-receptor antagonist, were studied on the memory performance of rats in a two-trial, delayed, place-recognition task. The drug was injected into the NBM area 2 min prior to the first trial (1.5, 7.5, and 37.5 ng/0.5 microl; pre-acquisition treatment), within 30 s from the end of the first trial (0.3, 1.5, 7.5, and 37.5 ng/0.5 microl; post-acquisition treatment), or 2 min prior to the second trial (1.5, 7.5, and 37.5 ng/0.5 microl; pre-retrieval treatment)., Results: Post-acquisition intra-NBM injections of 1.5 ng and 7.5 ng, but not of 0.3 ng and 37.5 ng thioperamide, significantly enhanced memory retention in treated rats. The histamine H(3)-receptor blocker exerted pro-cognitive effects only when administered post-acquisition, since both pre-acquisition and pre-retrieval treatments were ineffective. The post-acquisition effect of the drug was time dependent and disappeared when the drug was injected 90 min after the end of the first trial. The U-shaped dose-response relationship and the time dependency of the effect of thioperamide indicated that the drug acts on mechanisms involved in memory consolidation., Conclusions: The present findings demonstrate that the pro-cognitive effect of thioperamide is probably due to the modulation of post-acquisition memory processes through an action on the cholinergic basal forebrain. Our results indicate also that H3-antagonists may provide a useful approach for improving spatial recognition memory.

Gemcitabine (2',2'-difluoro-2'-deoxycytidine, or dFdC) is a promising anticancer agent with demonstrated clinical activity in solid tumours currently undergoing clinical trials. Despite extensive studies on the biochemical mechanism of action, cell cycle perturbations induced by dFdC have not yet been thoroughly investigated, apart from the expected inhibition of DNA synthesis. The aim of our study was to clarify whether cell population kinetics is a vital factor in the cytotoxicity of dFdC in single or repeated treatments and in the dFdC-cisplatin combination. Ovarian cancer cells growing in vitro were treated with dFdC for 1 hr in a range of concentrations from 10 nM to 10 microM. Cell kinetics was investigated by DNA-bromodeoxyuridine flow cytometry, using different experimental protocols to measure either the time course of DNA-synthesis inhibition or the fate of cells in G(1), S or G(2)M at the time of dFdC treatment or 24 hr later. A modified sulforhodamine B test was used to assess the growth inhibition caused by dFdC given alone or with cisplatin. Although dFdC promptly inhibited DNA synthesis, cytotoxicity on proliferating cells was not specific for cells initially in the S phase. DNA synthesis was restored after a G(1) block of variable, dose-dependent length, but recycling cells were intercepted at the subsequent checkpoints, resulting in delays in the G(2)M and G(1) phases. The activity of repeated treatment with dFdC + dFdC or dFdC + cisplatin was highly dependent on the interval length between them. These results suggest that the kinetics of cell recycling from a first dFdC treatment strongly affects the outcome of a second treatment with either dFdC itself or cisplatin., (Copyright 2001 Wiley-Liss, Inc.)

The Rantox biosensor was designed for anaerobic wastewater treatment process control, and detects modifications of the feed based on the response of the acetoclastic methanogens contained in the sensor to periodic pulses of a concentrated organic substrate. The biosensor was tested under various operating conditions at the laboratory scale, in parallel with a digester under control fed on the same substrate. The aim was to evaluate the response of the biosensor in the presence of an incoming organic toxic compound (CHCl3). The experimental set-up, i.e. the biosensor and the digester, was connected to an automated control system developed under LabVIEW environment for data acquisition and operational sequence programming (the Rantox Virtual Instrument). Biomasses with different activities were used as inocula, and inhibition was induced by dosing chloroform according to two different procedures. The results showed good sensitivity and rapid response of the biosensor to feed intoxication. The presence of chloroform was detected by the Rantox with a rapid and visible response, and well in advance with respect to the digester.

The purpose of this study was to describe the force/velocity and power/velocity relationships obtained during squat exercise. The maximal force (F0) was extrapolated from the force/velocity relationship and compared to the isometric force directly measured with the aid of a force platform placed under the subject's feet. Fifteen international downhill skiers [mean (SD) age 22.4 (2.6) years, height 178 (6.34) cm and body mass 81.3 (7.70) kg] performed maximal dynamic and isometric squat exercises on a guided barbell. The dynamic squats were performed with masses ranging from 60 to 180 kg, which were placed on the shoulders. The force produced during the squat exercise was linearly related to the velocity in each subject (r2 = 0.83-0.98, P < 0.05-0.0001). The extrapolated F0 was 23% higher than the measured isometric force (P < 0.001), and the two measurements were not correlated. This may be attributed to the position of the subject, since the isometric force was obtained at a constant angle (90 degrees of knee flexion), whereas the dynamic forces were measured through a range of movements (from 90 degrees to 180 degrees). The power/velocity relationship was parabolic in shape for each subject (r2 = 0.94-0.99, P < 0.01-0.0001). However, the curve obtained exhibited only an ascending part. The highest power was produced against the lightest load (i.e., 60 kg). The maximal power (Wmax) and optimal velocity were never reached. The failure to observe the descending part of the power/velocity curve may be attributed to the upper limitation of the velocities studied. Nevertheless, the extrapolation of Wmax from the power/velocity equation showed that it would be reached for a load close to body mass, or even under unloaded conditions.

Thirty light Parma hams were tested for muscle lipolytic activity (acid and neutral lipase activity) and free fatty acid (FFA) amounts in M. semimembranosus and biceps femoris, during progressive phases (0, 3, 6, 10 months) of dry-cured ham manufacturing. No correlation was found between the activities of acid and neutral lipases in fresh M. semimembranosus, while during processing the activities were positively related (p<0.1), probably due to effects of muscle composition changes on lipolytic activities. In each processing step tested, acid lipase activities were higher in the M. semimembranosus than in the M. biceps femoris, and FFA amounts varied accordingly, the only exception being for the very dehydrated 10-month old M. semimembranosus, which yielded lower FFA than in the corresponding M. biceps femoris. FFAs in the end product correlated positively with acid and neutral lipase activities of green ham, suggesting that FFA production could be influenced by both raw meat properties and muscle composition during processing.

An investigation was carried out on oxidative processes in dry-cured hams. Sixteen hams of various ageing times were divided into lean and fat parts, simulating typical consumer habits. All samples underwent analysis of peroxide value (PV), rancidity index (TBARs), 5 cholesterol oxidation products (COPs) and, in the lean samples, proximate composition. While the lean part was rather unaffected by oxidation, the external fat contained some of COPs, TBARs and PV. Comparison of hams at different ageing times revealed that lipid oxidation was substantially unaffected by the time of processing. It is concluded that good manufacturing practice will generally prevent oxidative damage in the edible part of dried hams, even if very long ageing times are used.

This study was done to determine whether leg stiffness (Kleg) during running was related to rearfoot-to-forefoot angle in standing (RFAst) and running (RFArun). Footprints obtained from 32 subjects were used to calculate RFAst and RFArun, defined as positive when forefoot axis was abducted from rearfoot axis. A spring-mass model was used to calculate Kleg in running from ground reaction forces, measured by a force platform. The Kleg of runners (13.0 +/- 2.7 kN x m(-1)) was negatively correlated with RFAst (-8.4 degrees +/- 6.4 degrees) and RFArun (-0.4 degrees +/- 7.2 degrees). When runners were divided into opened foot (RFArun > 0; N = 19) and closed foot (RFArun < 0; N = 12) groups, the Kleg of opened foot runners was less than that of the closed runners. We suggest that foot structure is a factor responsible for the differences in leg stiffness observed in runners.

The purpose of this study was to determine the possible mechanisms explaining the interindividual differences in foot orientations observed during running. Foot orientations, foot pressures, and ankle dorsiflexion and plantarflexion were simultaneously recorded on 12 male subjects running barefooted at 3.9 +/- 0.6 m.sec-1. The abduction of the forefoot was significantly related to the ankle dorsiflexion and plantarflexion velocities (P < 0.01 and P < 0.05, respectively). Because it was not possible, from pressure measurements, to determine differences in foot lever arm of runners, it is suggested that the interindividual variability of foot kinematics could not be explained by Bojsen-Møller's model, but could reflect differences in the lower limb stiffness control.

A study was conducted to evaluate the performance of 4 different assays for rapidly screening samples of artificially contaminated hams and salami for the presence of aflatoxins (B1+B2+G1+G2) at concentrations ≥5 μg/kg. Test samples were contaminated in the range of 0 - 100μg/kg.At 0 μg/kg level no false positive (all <5 μg/kg) were found for all commodities by the kits tested; all test samples spiked at level >20 μg/kg were found positive by each kit, while most of the errors associated in the assays occurred on samples containing <10μg/kg. For samples either negative or contaminated above 20μg/kg all the methods were suited for use as rapid screening tests.

Fifty cases of Hodgkin's disease in intravenous drug users (IVDU) have been collected by the Italian Cooperative Group on AIDS-Related Tumors (G.I.C.A.T.). Ninety-two per cent of the patients were males; the median age was 26 years. Persistent generalized lymphadenopathy (PGL) at onset was present in 54% of patients, AIDS in 9%, ARC in 9% while 28% were simply HIV-positive. The initial median absolute number of CD4 lymphocytes was 264/mmc. Opportunistic infections were diagnosed in 20% of patients. In most patients the histological pattern was that of mixed cellularity and lymphocytic depletion (76%). In almost half the initial symptom was a persistent lymph node enlargement due to PGL. In the majority of patients (58%) only a clinical staging and bone marrow biopsy could be performed due to the presence of opportunistic infections, rapid disease progression or refusal of pathologic staging procedures. One patient presented with a Waldeyer's ring involvement, but no other unusual presentations were observed. After MOPP alternated or followed by ABVD or MOPP alone, 15/29 CR (52%) and 14/29 PR (48%) were observed. The median duration of CR was 14 months, while the median survival of CR has not been reached; the median survival of patients treated with chemotherapy with CD4 values at presentation {geq}400/mmc was significantly superior to that in those with CD4 < 400/mmc. The overall median survival was 16 months. Twenty-eight per cent of patients receiving chemotherapy + radiotherapy developed opportunistic as well as non-opportunistic infections (21%). Lethal hepatic toxicity was observed in 2 patients. In conclusion, Hodgkin's disease in IVDU was not found to be associated with unusual presentations, as previously reported for homosexuals. Complete remissions could be achieved in over 50% of patients, but in IVDU non-opportunistic infections in addition to opportunistic infections may also limit treatment administration. The presence of parenchymal functional impairment due to drug abuse, or drug abuse-related infections, such as pneumonia, endocarditis and hepatitis, should lead to the choice of antitumour agents with no or only minor potential liver, lung and cardiac toxicity.