Genomic, metabolomic, and functional characterisation of beneficial properties of Pediococcus pentosaceus ST58, isolated from human oral cavity.

Bacteriocins produced by lactic acid bacteria are proteinaceous antibacterial metabolites that normally exhibit bactericidal or bacteriostatic activity against genetically closely related bacteria. In this work, the bacteriocinogenic potential of Pediococcus pentosaceus strain ST58, isolated from oral cavity of a healthy volunteer was evaluated. To better understand the biological role of this strain, its technological and safety traits were deeply investigated through a combined approach considering physiological, metabolomic and genomic properties. Three out of 14 colonies generating inhibition zones were confirmed to be bacteriocin producers and, according to repPCR and RAPD-PCR, differentiation assays, and 16S rRNA sequencing it was confirmed to be replicates of the same strain, identified as P. pentosaceus, named ST58. Based on multiple isolation of the same strain (P. pentosaceus ST58) over the 26 weeks in screening process for the potential bacteriocinogenic strains from the oral cavity of the same volunteer, strain ST58 can be considered a persistent component of oral cavity microbiota. Genomic analysis of P. pentosaceus ST58 revealed the presence of operons encoding for bacteriocins pediocin PA-1 and penocin A. The produced bacteriocin(s) inhibited the growth of Listeria monocytogenes, Enterococcus spp. and some Lactobacillus spp. used to determine the activity spectrum. The highest levels of production (6400 AU/ml) were recorded against L. monocytogenes strains after 24 h of incubation and the antimicrobial activity was inhibited after treatment of the cell-free supernatants with proteolytic enzymes. Noteworthy, P. pentosaceus ST58 also presented antifungal activity and key metabolites potentially involved in these properties were identified. Overall, this strain can be of great biotechnological interest towards the development of effective bio-preservation cultures as well as potential health promoting microbes.

Effects of phenanthrene on different levels of biological organization in larvae of the sediment-dwelling invertebrate Chironomus sancticaroli (Diptera: Chironomidae).

The hydrocarbon phenanthrene is an organic compound commonly found in the environment. In aquatic ecosystems, it is highly toxic to organisms, although little is known about its effects on sediment-dwelling organisms. The purpose of this study was to evaluate phenanthrene effects on biochemical, histological, and ontogenetic levels in larvae of the sediment-dwelling invertebrate Chironomus sancticaroli at acute and chronic exposure. Lethal concentrations were estimated and toxicity (acute-96 h and chronic- 8 d) tests were performed at phenanthrene concentrations from 0.12 to 1.2 mg L-1. At acute and chronic exposure, we evaluated acetylcholinesterase (AChE), alpha esterase (EST-α), and beta esterase (EST-ß) activities as well as histological alterations. In the assays with chronic exposure, effects on larval development were estimated using antennae length (instar estimative) and body length (growth estimative). The EST-α showed a significantly increased activity after 48 h at acute exposure to high concentrations of phenanthrene, while EST-ß activity was increased after 48 and 72 h at acute exposure at higher concentrations and at 0.12 mg L-1 at chronic exposure. At acute exposure, the midgut showed alterations such as brush border disruption, gastric caeca regression, and lumen area reduction; the fat body showed nuclear alteration in the trophocytes, while the Malpighian tubules showed brush border reduction and the salivary glands were subject to cytoplasm vacuolation. At chronic exposure, the same alterations were observed, in addition to vacuolar coalescence in the trophocytes of the fat body. Regarding larval development, a reduction of body length was observed with increasing phenanthrene concentrations. Similarly, molting was delayed; in the control group, all larvae were in the fourth instar, while at higher phenanthrene concentrations, larvae were predominantly in the third instar. Phenanthrene had toxic effects on this chironomid, indicating risks for natural populations.

Metals in Feathers of African Penguins (Spheniscus demersus): Considerations for the Welfare and Management of Seabirds Under Human Care.

Bird feathers have been proven to be reliable indicators of metal exposure originating from contaminated food and polluted environments. The concentrations of 15 essential and non-essential metals were investigated in African penguins (Spheniscus demersus) feathers from a Northwestern Italian zoological facility. These birds are exclusively fed with herring from the northeast Atlantic Ocean. Certain elements, such as Hg and Cd, reflected the bioaccumulation phenomena that occur through the marine food chain. The levels of Cr, Mn, and Ni were comparable to those registered in feathers of birds living in polluted areas. These results are important for comparative studies regarding the health, nutrition and welfare of endangered seabirds kept under human care.

Genome Sequence of Rhizobium sullae HCNT1 Isolated from Hedysarum coronarium Nodules and Featuring Peculiar Denitrification Phenotypes.

The genome sequence of Rhizobium sullae strain HCNT1, isolated from root nodules of the legume Hedysarum coronarium growing in wild stands in Tuscany, Italy, is described here. Unlike other R. sullae strains, this isolate features a truncated denitrification pathway lacking NO/N2O reductase activity and displaying high sensitivity to nitrite under anaerobic conditions.

Fast method for the determination of short-chain-length polyhydroxyalkanoates (scl-PHAs) in bacterial samples by In Vial-Thermolysis (IVT).

A new method based on the GC-MS analysis of thermolysis products obtained by treating bacterial samples at a high temperature (above 270°C) has been developed. This method, here named "In-Vial-Thermolysis" (IVT), allowed for the simultaneous determination of short-chain-length polyhydroxyalkanoates (scl-PHA) content and composition. The method was applied to both single strains and microbial mixed cultures (MMC) fed with different carbon sources. The IVT procedure provided similar analytical performances compared to previous Py-GC-MS and Py-GC-FID methods, suggesting a similar application for PHA quantitation in bacterial cells. Results from the IVT procedure and the traditional methanolysis method were compared; the correlation between the two datasets was fit for the purpose, giving a R2 of 0.975. In search of further simplification, the rationale of IVT was exploited for the development of a "field method" based on the titration of thermolyzed samples with sodium hydrogen carbonate to quantify PHA inside bacterial cells. The accuracy of the IVT method was fit for the purpose. These results lead to the possibility for the on-line measurement of PHA productivity. Moreover, they allow for the fast and inexpensive quantification/characterization of PHA for biotechnological process control, as well as investigation over various bacterial communities and/or feeding strategies.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA): emerging contaminants of increasing concern in fish from Lake Varese, Italy.

Perfluoroalkylated substances (PFASs) are highly fluorinated aliphatic compounds with high thermal and chemical stability, used in a range of industrial applications. Extensive screening analyses in biota samples from all over the world have shown the bioaccumulation of PFAS into higher trophic levels in the food chain. Perfluorooctane sulfonic acid (PFOS) and perfluoroctanoic acid (PFOA) are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. Ingestion of fish and other seafood is considered the main source of exposure of these contaminants. Here, we quantified PFOS and PFOA by LC-MS/MS in muscle samples of European perch from Lake Varese, Italy. PFOS was detected in all samples with concentrations of up to 17.2 ng g(-1). Although the reported values were lower than the recommended total daily intake (TDI) proposed by the European Food Safety Authority (EFSA), fish from Lake Varese may be a significant source of dietary PFOS exposure.

Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) in eel, trout, and barbel from the River Roya, Northern Italy.

Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) contribute to the dietary intake of total PCBs. They are consumed via ingestion of contaminated fish and fishery products. Thus, it is important to quantify their levels in aquatic organisms in order to evaluate the risks associated with fish consumption by humans. In 2013, an advisory against consumption of fish from the River Roya (IT) was disseminated after NDL PCBs were found to exceed maximum levels set by EU Regulations. We investigated the presence of NDL PCBs in eel, trout and barbel from the River Roya. We found concentrations in the range of 9.2-27.6 ng g(-)(1)ww in barbel, 9.2-97.0 ng g(-1)ww in trout and 9.0-239.5 ng g(-1)ww in eel. The distribution of congeners among different species did not show significant variations and was characterized by a higher proportion of 153, 138 and 180 congeners, according to their high resistance to metabolic degradation.

Association of a specific major histocompatibility complex class IIß single nucleotide polymorphism with resistance to lactococcosis in rainbow trout, Oncorhynchus mykiss (Walbaum).

Major histocompatibility complex (MHC) loci encode glycoproteins that bind to foreign peptides and initiate immune responses through their interaction with T cells. MHC class II molecules are heterodimers consisting of α and ß chains encoded by extremely variable genes; variation in exon 2 is responsible for the majority of observed polymorphisms, mostly concentrated in the codons specifying the peptide-binding region. Lactococcus garvieae is the causative agent of lactococcosis, a warm-water bacterial infection pathogenic for cultured freshwater and marine fish. It causes considerable economic losses, limiting the profitability and development of fish industries in general and the intensive production of rainbow trout, Oncorhynchus mykiss (Walbaum), in particular. The disease is currently controlled with vaccines and antibiotics; however, vaccines have short-term efficacy, and increasing concerns regarding antibiotic residues have called for alternative strategies. To explore the involvement of the MHC class II ß-1 domain as a candidate gene for resistance to lactococcosis, we exposed 400 rainbow trout to naturally contaminated water. One single nucleotide polymorphism (SNP) and one haplotype were associated with resistance (P < 0.01). These results are promising for using MHC class IIß as a molecular marker in breeding rainbow trout resistant to lactococcosis.

Fish consumption as a source of human exposure to perfluorinated alkyl substances in Italy: analysis of two edible fish from Lake Maggiore.

Extensive screening analyses of perfluorooctane sulfonate and related perfluorinated compounds (PFCs) in biota samples from all over the world have identified PFCs as global pollutants and have shown their bioaccumulation into higher trophic levels in the food chain. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are environmental contaminants belonging to a chemical group known as perfluorinated compounds. PFOS and PFOA are very persistent in the environment and bioaccumulate in humans. They are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. The United States Environmental Protection Agency (USEPA) considers both compounds to be carcinogenic and the European Food Safety Authority (EFSA) recently pointed out that they are associated with adverse health effects. Diet is considered the main source of exposure to PFCs, which have been found more frequently in fish and other seafood, compared to other food groups. In fact, aquatic ecosystems represent the final reservoir for PFCs due to their great affinity for sedimentary and living organic matter. In these systems, measured levels of persistent organic pollutants (POPs) could increase along the trophic web, ultimately affecting humans that consume aquatic species. In this study, PFOS and PFOA was detected by LC-MS/MS in muscle samples of Coregonus lavaretus (European whitefish) and Perca fluviatilis (European perch) collected from Lake Maggiore, a large lake located on the south side of the Italian Alps. PFOA was not found in any of the investigated samples above the limit of quantitation of 0.50 ng g(-1) fresh weight (fw), whereas PFOS was detected in all 90 samples with concentrations of up to 46.0 ng g(-1)fw. Mean concentrations were 22.2 ng g(-1)fw in P. fluviatilis and 20.0 ng g(-1)fw in C.lavaretus. Comparison of our results with literature data on PFOS intake suggested that fish from Lake Maggiore may be a significant source of dietary PFOS exposure, even if the reported values were lower than the Total Daily Intake (TDI) proposed by EFSA.

NDL-PCBs in muscle of the European catfish (Silurus glanis): an alert from Italian rivers.

The non-dioxin-like polychlorinated biphenyls (NDL-PCBs) highly contribute to the PCB dietary intake of total PCBs. Most of the NDL-PCBs are assumed through ingestion of contaminated fish and fishery products. Therefore, it is important to quantify their presence in aquatic organisms to evaluate human risks associated with fish consumption. The European catfish is a top food-chain predator and is considered a reliable bio-monitoring tool reflecting the state of the environmental organic pollution. From 2006 to 2009, 54 European catfish were captured in four sites covering the area of the Po River (North Italy), and their muscles were analysed to determine the levels of 18 PCBs congeners. All samples presented detectable levels of 18 congeners and, on average, results showed an important presence of NDL-PCBs. The sum of the six congeners (28, 52, 101, 138, 153, 180 IUPAC) was used as indicator of the total PCBs concentration. The 33% of the samples analysed exceeded the maximum levels of 125 ng g(-1) set by European regulations in fish. The values measured ranged from 19.7 to 1015.4 ng g(-1) (mean 135.6 ± 149.8 ng g(-1)). The concentrations of NDL-PCBs were not related to fish weight or sex, while a significant variability was found among sites (p<0.05), according to the geographical location of many industrial activities in the catchment area of the Po River. PCB 153 and 138 were present in higher concentrations (40% and 30% respectively). We hypothesise that this is due to their high resistance to metabolic degradation.

Enterococcus faecium isolated from Lombo, a Portuguese traditional meat product: characterisation of antibacterial compounds and factors affecting bacteriocin production.

Strain ST211CH, identified as a strain of Enterococcus faecium, isolated from Lombo produced a bacteriocin that inhibited the growth of Enterococcus spp., Listeria spp., Klebsiella spp., Lactobacillus spp., Pseudomonas spp., Staphylococcus spp. and Streptococcus spp. The mode of action of the bacteriocin named as bacteriocin ST211Ch was bactericidal against Enterococcus faecalis ATCC19443. As determined by Tricine-SDS-PAGE, the approximate molecular mass of the bacteriocin was 8.0 kDa. Loss in antimicrobial activity was recorded after treatment with proteolytic enzymes. Maximum activity of bacteriocin ST211Ch was measured in broth cultures of E. faecium strain ST211Ch after 24 h; thereafter, the activity was reduced. Bacteriocin ST211Ch remained active after exposure to various temperatures and pHs, as well as to Triton X-100, Tween-80, Tween-20, sodium dodecyl sulfate, NaCl, urea and EDTA. Effect of media components on production of bacteriocin ST211Ch was also studied. On the basis of PCR reactions targeting different bacteriocin genes, i.e. enterocins, curvacins and sakacins, no evidences for the presence of these genes in the total DNA of E. faecium strain ST211Ch was obtained. The bacterium most probably produced a bacteriocin different from those mentioned above. Based on the antimicrobial spectrum, stability and mode of action of bacteriocin ST211CH, E. faecium strain ST211Ch might be considered as a potential candidate with beneficial properties for use in biopreservation to control food spoilage bacteria.

Equid herpesvirus type-1 exhibits neurotropism and neurovirulence in a mouse model.

Intranasal inoculation of equid herpesvirus type-1 (EHV-1) Brazilian strains A4/72 and A9/92 induced an acute and lethal infection in four different inbred mouse strains. Clinical and neurological signs appeared between the 2nd and 3rd day post inoculation (dpi) and included weight loss, ruffled fur, a hunched posture, crouching in corners, nasal and ocular discharges, dyspnoea, dehydration and increased salivation. These signs were followed by increased reactivity to external stimulation, seizures, recumbency and death. The virus was recovered consistently from the brain and viscera of all mice with neurological signs. Histopathological changes consisted of leptomeningitis, focal haemorrhage, ventriculitis, neuronal degeneration and necrosis, neuronophagia, non-suppurative inflammation, multifocal gliosis and perivascular infiltration of polymorphonuclear and mononuclear cells. Immunohistochemical examination demonstrated that EHV-1 strains A4/72 and A9/92 replicated in neurons of the olfactory bulb, the cortex and the hippocampus. In contrast, mice inoculated with the EHV-1 Brazilian strain A3/97 showed neither weight loss nor apparent clinical or neurological signs; however, the virus was recovered consistently from their lungs at 3 dpi. These three EHV-1 strains showed distinct degrees of virulence and tissue tropism in mice. EHV-1 strains A4/72 and A9/92 exhibited a high degree of central nervous system tropism with neuroinvasion and neurovirulence. EHV-1 strain A3/97 was not neurovirulent despite being detected in the brains of infected BALB/c nude mice. These findings indicate that several inbred mouse strains are susceptible to neuropathogenic EHV-1 strains and should be useful models for studying the pathogenesis and mechanisms contributing to EHV-induced myeloencephalopathy in horses.

Prospective clinical evaluation and follow-up of a cohort of consecutive VT/VF patients, using a staged-care protocol, including coronary arteriography, programmed electrical stimulation and cardiac surgery.

The prospective evaluation and follow-up of 39 consecutive subjects with VT/VF, 6 of whom, with cardiac arrest (CA), are reported. Patients were enrolled in a specific staged-care approach protocol, which included coronary arteriography (CAR) and ventriculography (VC), in order to exclude the need of cardiac surgery, including coronary artery bypass graft (CABG), with and without left ventricular aneurysmectomy (LVA). The protocol included inducibility of VT/VF, which was verified by programmed electrical stimulation (PES) in control conditions and after antiarrhythmic therapy (ADT), to assess persistent inducibility and mainly to verify the hemodynamic sequelae of VT. VT that showed poor hemodynamic tolerance was treated with ICD, while well-tolerated VT was treated by ADT or ablation when indicated. Furthermore, PES was obtained after surgical procedures. As a first step, the patients were assigned to receive amiodarone (AMIO) (200-400 mg/daily) in the presence of EF% < 30% or contraindication to sotalol, (Group A), or sotalol (SOT) (80-140 mg/daily) in the presence of EF > or = 31%. (Group C). Conversely, in case of recurrences, patients were assigned to receive AMIO (200-300 mg/daily) plus metoprolol (MET) (20-100 mg/daily), (Group B) or, in case of intolerance to beta-blockers, to AMIO plus mexiletine (MEX) (200 mg/daily) (Group D). The four groups were similar for the type of VA, with recurrent ventricular tachycardia (RVT) being the most frequent one. The most frequent underlying cardiac disease of VA in this study was post-AMI CAD, with a rate of over 60% in all four groups. Single- and two-vessel lesions were found at CAR in various patients in all four groups, in 5/13 (38%) in Group A, in 8/14 (57%) in Group B, in 5/7 (71%) in Group C, and in 3/5 (60%) in Group D. Cardiac surgery was performed in a similar and limited number of patients in all four groups, in 4/13 (30%) in Group A, in 4/14 (35%) in Group B, in 2/7 (28%) in Group C, and in 2/5 (40%) in Group D. In 8/39 (20.5%) of the patients who underwent CABG, there was no operative or late mortality; 4/39 (10.2%) received CABG and LVA, and two died. For the amiodarone plus metoprolol and sotalol patients only, PES showed a lower residual inducibility, in comparison to the amiodarone and amiodarone + mexiletine groups. In the entire group, 7 out of 26 (27%) were still inducibile at PES while in 19/26 (64%) of the patients, an apparently effective treatment could be found, documenting the relative usefulness of PES. Recurrence rate was the highest in the amiodarone + mexiletine group and in patients with previous CA. Our data show the potential utility and limitations of ADT, even using the most effective antiarrhythmic drugs and association of drugs, mainly because of the high recurrence rate of VT observed in the present study, even in non-inducible patients [14/39 (36%)]. In conclusion, in a prospective and staged-care approach protocol of management of VT/VF patients, only a few patients with VT/VF benefited from cardiac surgery. PES could still play a role in the evaluation of the most effective ADT. Amiodarone + metoprolol seems to be the most effective ADT in these patients. Nevertheless, a high recurrence rate was observed in this patient population, even with an aggressive protocol, in the short follow-up period of 12 +/- 8 months, confirming recent data on the superiority of ICD to ADT, in patients with frequent recurrences or hemodynamically poorly-tolerated VT. In these patients, ICD therapy should definitively be preferred to ADT.

Dactylitis in patients with seronegative spondylarthropathy. Assessment by ultrasonography and magnetic resonance imaging.

OBJECTIVE: To establish by means of ultrasound and magnetic resonance imaging (MRI) the role of tenosynovitis and arthritis in determining the "sausage-like" aspect of finger dactylitis and to compare the results of the 2 examinations. METHODS: Twelve dactylitic fingers and their corresponding normal contralateral fingers belonging to 10 patients who met the Amor criteria for the diagnosis of seronegative spondylarthropathy (SpA) were studied by ultrasonography and MRI. RESULTS: MRI revealed a significant increase in the volar bone-to-skin distance in dactylitic fingers with respect to that of the normal contralateral fingers (P < 0.001). This increase was due to distension of the flexor synovial sheaths (P < 0.00001) by fluid collection. Peritendinous soft tissues were not involved, since these were found to be significantly thicker in the normal fingers (P < 0.05). Of the 36 joints of the 12 dactylitic fingers, only 1 showed capsule distension. Using MRI as the "gold standard," ultrasonography showed a 100% sensitivity and specificity for flexor tenosynovitis, but lacked sensitivity for joint involvement because it failed to reveal joint capsule distension in the only joint involved. Similarly, physical examination showed a 100% sensitivity and specificity for flexor sheath involvement. CONCLUSION: Dactylitis is due to flexor tenosynovitis. Enlargement of the finger joint capsule is not an indispensable condition for the "sausage-like" feature. Physical examination is a sufficient method for the diagnosis of dactylitis.

Dactylitis with pitting oedema of the hand in longstanding ankylosing spondylitis.

The case of a patient with seronegative spondyloarthropathy showing oligoarthritis of the hand together with large pitting oedema is reported. Unlike the patients with late onset peripheral spondyloarthropathy described by Dubost and Sauvezie who show minimal involvement of the axial skeleton, the patient has been suffering from AS for about twenty years.

Late onset undifferentiated seronegative spondyloarthropathy.

OBJECTIVE: To define the clinical spectrum of late onset undifferentiated seronegative spondyloarthropathy (uSpA) based on a large number of patients. METHODS: All consecutive patients older than 45 years at the onset of SpA and not meeting criteria for any of the definite categories of the SpA complex seen in the 1988-1993 period were entered in a special register and were followed prospectively. RESULTS: Twenty-three patients (mean age at onset 56.9, range 46-72; mean age at the last visit 61.7, range 48-79) were studied. Of these, 12 had 3 or more clinical and/or radiological manifestations of SpA, while 7 showed only 2, and 4 only one. Of the 10 patients with peripheral arthritis, only 3 had the large pitting edema of the lower limbs described by Dubost and Sauvezie. Of the 4 patients with only one manifestation, 2 had peripheral enthesitis and 2 acute anterior uveitis. CONCLUSION: The clinical spectrum of late onset uSpA is as wide as in children and young and middle aged adults.