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This work investigated bacteriophage induced starter failures in artisanal buffalo Mozzarella production plants in Southern Italy. Two hundred and ten samples of whey starter cultures were screened for bacteriophage infection. Multiplex polymerase chain reaction (PCR) revealed phage infection in 28.56% of samples, all showing acidification problems during cheese making. Based on DNA sequences, bacteriophages for Lactococcus lactis (L. lactis), Lactobacillus delbruekii (L. delbruekii) and Streptococcus thermophilus (S. thermophilus) were detected. Two phages active against L. lactis, φApr-1 and φApr-2, were isolated and characterised. The genomes, approximately 31.4 kb and 31 kb for φApr-1 and φApr-2 respectively, consisted of double-stranded linear DNA with pac-type system. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS--PAGE) showed one major structural protein of approximately 32.5 kDa and several minor proteins. This is the first report of phage isolation in buffalo milk and of the use of multiplex PCR to screen and study the diversity of phages against Lactic Acid Bacteria (LAB) strains in artisanal Water Buffalo Mozzarella starters.

A total of 47 Listeria monocytogenes strains isolated in a survey of cheeses sampled from retail outlets were characterised. Five cheeses (Gorgonzola, Taleggio, Asiago, Crescenza and Brie) were chosen from the most popular soft and semi-soft cheeses consumed in Italy and most commonly contaminated with L. monocytogenes. The serotype and antibiotic resistance pattern were determined for each strain and their macrorestriction profile was analysed with pulsed-field gel electrophoresis (PFGE). The main serotypes detected were 1/2a (76.6%) and 1/2c (21.3%). Serotype 1/2b was found in only one sample. A total of 97.9% of strains were resistant to oxacillin (OX), 80.9% to lincomycin (L) and 78.7% to clindamycin (CC). Of these strains, 17% were found to be resistant to two antibiotics (OX-CC or OX-L) while 70.2% were resistant to three antibiotics (OX-CC-L). No strains were susceptible to all the compounds tested. A combined analysis of the macrorestriction profiles AscI and ApaI identified eleven pulsotypes divided into three clusters. Two pulsotypes predominated, accounting for 57.4% and 21.3% of the isolated strains. Analysis of the PFGE profiles did not reveal any correlation between pulsotype and type of cheese, producer or retail outlet. A temporal analysis revealed that one pulsotype was persistent throughout the study period, with the exception of August and September, in which time a different pulsotype was detected. This variability suggests the influence of factors affecting the dynamics of the contamination of these products. Large-scale studies could help clarify this phenomenon.

To help identify an epidemiological link between the consumption of buffalo mozzarella prepared with raw milk (not heat-treated) and cases of human brucellosis, 80 samples of raw buffalo milk and 315 samples of mozzarella were tested for the presence of Brucella spp. Samples originated from Caserta, the province with the highest number of Brucella-positive buffalo herds in Campania, the region in which 96.02% of all cases of human brucellosis reported in 2000-2005 were recorded. To take into account possible seasonal variations, between February 2006 and March 2007, samples were purchased directly from 72 dairy outlets that were representative of the province. Samples were tested for Brucella spp. using the polymerase chain reaction (PCR) and bacterial isolation. Samples tested negative for Brucella using both methods. Spiked samples were then prepared and tested by PCR and bacterial isolation and the sensitivity, specificity, repeatability, reproducibility and limit of detection were determined. The PCR limit of detection was below 1 colony-forming unit (cfu)/g. The repeatability and reproducibility of the method were 100% (p = 0.95), the sensitivity was 96.7% (p = 0.95) and the specificity was 100% (p = 0.95).

This study analysed 37 samples of clams (Chamelea gallina) collected along the coasts of Abruzzo Region for Vibrio spp. detection from May to October in 2007. Biochemical tests according to Alsina scheme were performed on 30 strains for Vibrio splendidus identification. Molecular analysis of the intergenic space region 16S-23S and rec-A gene were used in order to identify V. splendidus and related species.

Human listeriosis is a foodborne disease of great concern for pubblic health. Numerous outbreaks connected with pork meat are reported every year in Europe like in USA. Different sources are considered for contamination and one of these is slaughterhouse. We have investigated thirteen Italian slaughterhouses to assess the contamination of pork meat and to investigate the sources of contamination. 791 carcasses and 511 faeces were analized. We have found 2.9% of carcasses contaminated by L. monocytogenes and only one faeces

From October 2003 to february 2005, 791 carcass swabs and 511 faecal samples were collected in 13 slaughterhouses located in northern Italy. Sampled animals were selected among farms located in four different Italian regions, in order to ensure a precise sample size from each region. Faecal samples were tested for presence of Salmonella spp., while carcass swabs were analysed for both presence and enumerating of Salmonella. The counting tecnique used in this study was the MPN method. 9.6% of tested animals were identified as Salmonella spp. carriers. This prevalence is lower than data reported in recent italian studies. On the other hand, prevalence on carcasses was much higher than as reported in studies conducted in Italy and other european countries. We found that 28.3% of positive carcasses carried levels of Salmonella over 0,10 MPN/g, ranging from 0,10 to 4,76 MPN/g. A correlation between slaughterhouses contamination and prevalence of Salmonella in carcasses was found. However, further studies, as complete characterization of strains, should be necessary to obtain conclusive informations.

Shell eggs sampled at retail outlets in two large Italian cities were tested to assess their freshness, food safety and the presence of veterinary drug residues. Some samples were found to be irregular due to lack of compliance with freshness requirements or shells were tainted by micro-cracks and foreign material. The most severe case of non-compliance was due to the presence of veterinary drug residues that either exceeded either the maximum acceptable residue limits or drugs that were prohibited.

The determination of the origin of foodborne diseases is one of the top priorities for the world health community. Gastroenteritis caused by zoonotic Salmonella serovars is one of the major threats to human health. It is essential that surveillance systems are able to monitor the incidence of human cases and to provide useful data to plan and implement effective prevention strategies. Surveillance systems generate information that is of value both for the early detection of infection and for the identification of epidemiological trends and risk factors. The authors describe a surveillance system for the identification of the sources of infection foodborne disease outbreaks caused by Salmonella in the Abruzzo region of Italy between April 2000 and October 2002.

Because studies have shown that 17beta-estradiol (E2) produces anti-inflammatory effects after various adverse circulatory conditions, we have recently demonstrated that E2 significantly reduced the acute lung injury. Moreover, previous results suggest that peroxisome proliferator-activated receptor-alpha (PPAR-alpha), an intracellular transcription factor activated by fatty acids, plays a role in the control of inflammation. With the aim to characterize the role of PPAR-alpha in estrogen-mediated anti-inflammatory activity, we tested the efficacy of E2 in an experimental model of lung inflammation, carrageenan-induced pleurisy, comparing ovariectomized wild-type (WT) and PPAR-alpha lacking (PPAR-alphaKO) mice. Results indicate that E2-mediated anti-inflammatory activity is weakened in PPAR-alphaKO mice, compared with WT control groups. In particular, E2 was less effective in PPAR-alphaKO, compared with WT mice, in inhibition of cell migration as well as lung injury, NF-kB activation, TNF-alpha production, and inducible nitric-oxide synthase (iNOS) activation. Moreover, macrophages from PPAR-alphaKO were less susceptible to E2-induced iNOS inhibition in vitro compared with macrophages from WT mice. Moreover, the results indicate that PPAR-alpha was required for estrogen receptor up-regulation, following E2 treatment. These results show for the first time that PPAR-alpha contributes to the anti-inflammatory activity of E2.

Glucocorticoid hormones (GCH) have been implicated as regulators of T-lymphocyte growth and differentiation. In particular, it has been reported that GCH can induce thymocyte apoptosis. However, the molecular mechanisms responsible for this GCH-induced death have not been clarified. In this work, the biochemical events associated with apoptosis induced by Dexamethasone (Dex), a synthetic GCH, in normal mouse thymocytes, have been analyzed. Results indicate that Dex-induced thymocyte apoptosis is attributable to an early ceramide generation caused by the activation of an acidic sphingomyelinase (aSMase). Caspase activity plays a crucial role in Dex-induced apoptosis and is downstream the aSMase activation in that inhibition of the early ceramide generation inhibits caspase activation and thymocyte death. Moreover, Dex treatment rapidly induces diacylglycerol (DAG) generation, through a protein kinase C (PKC) and G-protein–dependent phosphatidylinositol-specific phospholipase C (PI-PLC), an event which precedes and is required for aSMase activation. Indeed, PI-PLC inhibition by U73122 totally prevents Dex-induced aSMase activity, ceramide generation, and consequently, caspase activation and apoptosis. All these effects require Dex interaction with GCH receptor (GR), are countered by the GR antagonist RU486, and precede the GCH/GR-activated transcription and protein synthesis. These observations indicate that GCH activates thymocyte death through a complex signaling pathway that requires the sequential activation of different biochemical events.