The effects of the oxidant species peroxynitrite (ONOO-) on coronary perfusion pressure and vasodilatation elicited by acetylcholine, isoproterenol, and S-nitroso-N-acetyl-DL-penicillamine were investigated in the isolated perfused rat heart. ONOO-(0.3-1000 AM) caused a concentration-dependent vasodilatation of the coronary vasculature. This dilator response was inhibited by oxyhemoglobin, indicating that it was due to the generation of nitric oxide. Tachyphylaxis to ONOO-developed rapidly, so that the response disappeared after three or four applications of this compound. ONOO-not only induced tachyphylaxis but also inhibited the vasodilatation induced by the three vasodilators studied. This latter effect of ONOO-was critically dependent on its concentration, since it occurred at 3 ,iM, which was subthreshold as a dilator, and at 1000 ,IM, which was supra- have found that ONOO-causes aggregation of washed human platelets (11). However, this aggregatory action of ONOO-was abolished in the presence of thiols as a result of the generation of S-nitrosothiols and/or NO, which inhibited aggregation. This led us to suggest that the fate and the actions of ONOO-are critically dependent on the microenvironment in which this oxidant is generated (11).The present experiments were carried out to investigate the actions of ONOO-in the coronary circulation, where NO is produced physiologically (12-15) and where O2 (16) and possibly ONOO-(17) may be generated in pathological conditions. METHODS Isolated Perfused Heart Preparation. Male Wistar rats (200-250 g) were anesthetized with isoflurane (2%), injected with heparin (200 units) and decapitated. The isolated perfused hearts were prepared according to a modified method of Langendorff. In brief, the hearts were isolated and a proximal pulmonary arteriotomy was performed for drainage of coronary effluent. They were then placed in a jacketed chamber (37°C) and perfused through the aorta by means of a roller pump (Minipuls2, Gilson) with Krebs-Henseleit solution (118 mM NaCl/2.8 mM KCl/1.2 mM KH2PO4/2.5 mM CaCl2/1.2 mM MgSO4/25 mM NaHCO3/5.5 mM glucose, pH 7.4) at 37°C that had been bubbled with a mixture of 95% 02 and 5% CO2. The perfusion rate was maintained at 9 ml/min, resulting in an initial coronary perfusion pressure (CPP) of 50-60 mmHg (1 mmHg = 133 Pa). Hearts with a CPP outside this range were discarded. The CPP was monitored with an Elcomatic EM750 transducer connected to a Gould TA-4000 monitoring system. The hearts were electrically paced at a frequency of 320 beats/min with an S44 Grass stimulator. They were allowed to stabilize for 10 min, after which time the CPP was increased to 120-140 mmHg by using the thromboxane A2 mimetic U-46619 (EC80 6 nM; n = 6).Each experiment was completed within 2 hr of isolation ofthe preparation.Experimental Design. ONOO-(0.3-1000 ,uM) or the products of its decomposition (dec ONOO-, see below) were infused directly into the aortic cannula (<1-sec delay before reaching the heart) for 30 sec at 100 ,ul/min. The pH of the per...

Nitric oxide (NO) is generated from L-arginine by a family of enzymes called the NO synthases. Previous investigators have proposed that the expression of this inducible enzyme (iNOS) may account for the characteristic vasodilatation, oedema and impairment of get motility seen in active ulcerative colitis. Using a specific antibody to iNOS, we have investigated the distribution of this enzyme in colonic tissue from patients with histologically proven ulcerative colitis. Eight patients with ulcerative colitis expressed calcium-independent citrulline activity (9.96 +/- 2.34 pmol citrulline mg-1 protein min-1) and showed immunoreactivity to the iNOS antibody within the inflammatory infiltrate of the lamina propria, and also within the cytoplasm of the epithelial cells lining the colon. Five age-matched controls showed no calcium-independent citrulline activity (0.2 +/- 0.08 pmol citrulline mg-1 protein min-1) and no immunoreaction to the antibody. We conclude that this enzyme is present in colonic tissue including the epithelium from patients with active colitis. Inhibition of this enzyme may provide a novel therapeutic option for patients with active ulcerative colitis.

Wild boar is a source of human infections with zoonotic pathogens, including food-borne parasites. With the aim of a characterization of the human exposure risk, a survey on wild boars intended for human consumption was planned, selecting three pathogens, Toxoplasma gondii, Alaria alata, and Trichinella spp., as markers of meat infection. Diaphragm muscle samples from 100 wild boars hunted in Piedmont region (Northern Italy) in two hunting seasons (2015-2016) were collected. Concerning T. gondii, a combined approach of antibody detection and molecular techniques with genotyping was performed. For the detection of A. alata and Trichinella spp., the larva migration technique and the magnetic stirrer method were employed, respectively; in addition, molecular confirmation of the morphological identification of the recovered specimen was performed. Anti-T. gondii antibodies were found in meat juice samples (43.3%) and T. gondii DNA (type II) was detected in three animals (7.1%) out of 42 seropositive examined. In none of the sampled wild boars (0%), Trichinella spp. larvae were found, whereas one animal (1%) scored positive to A. alata mesocercariae. The molecular diagnosis proved the morphological identification of the trematode. This is the first finding of A. alata in Italian wild boar population. The present study confirmed the role of wild boars as a source of parasitic zoonotic diseases and thus the risk derived for humans posed by the consumption of game meat. Considering the zoonotic implications, the results underline the importance of monitoring and surveillance of zoonotic parasites in Italian wild boar populations.

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Toxoplasma gondii is a widespread protozoan affecting animals and humans. One of the major routes of human infection is through the consumption of raw or under-cooked meat, particularly of certain animal species, including pigs. Although T. gondii represents an important public health issue, its control at slaughter is not mandatory. Consequently, available information on T. gondii infection in domestic animals destined for human consumption is scarce. Thus, an epidemiologic survey was designed to update information on T. gondii infection in pigs from intensive production. Fattening pigs and sows from conventional farms were sampled. Sera were tested with a commercial ELISA for anti-T. gondii antibodies, whereas molecular analysis by 529 bp repetitive element PCR and B1 real-time PCR with subsequent genotyping was performed on heart samples. Statistical analysis was carried out to detect farm management features and sanitary procedures enhancing the risk of infection. At the farm level, 63.6% (7/11) of farms housing sows and 6.7% (1/15) housing fattening pigs scored positive, with individual prevalences of 8.6% (13/151) in sows and 0.5% (1/219) in fattening pigs. T. gondii DNA was detected in eight sows and one fattening pig, and sequencing revealed the presence of all three genotypes (types I, II, and III). Furthermore, the decrease in the biosecurity level enhanced the risk of infection within a farm. The present survey outcomes confirm the spread of T. gondii infection in pig farms in an area of intensive swine production. The application of stricter sanitary procedures may contribute to a further reduction of infection.