Electron and ion spectroscopy of azobenzene in the valence and core shells

Azobenzene is a prototype and a building block of a class of molecules of extreme technological interest as molecular photo-switches. We present a joint experimental and theoretical study of its response to irradiation with light across the UV to x-ray spectrum. The study of valence and inner shell photo-ionization and excitation processes combined with measurement of valence photoelectron-photoion coincidence and mass spectra across the core thresholds provides a detailed insight into the site- and state-selected photo-induced processes. Photo-ionization and excitation measurements are interpreted via the multi-configurational restricted active space self-consistent field method corrected by second order perturbation theory. Using static modeling, we demonstrate that the carbon and nitrogen K edges of azobenzene are suitable candidates for exploring its photoinduced dynamics thanks to the transient signals appearing in background-free regions of the NEXAFS and XPS

Characterization of the inflammatory cell infiltrate and expression of costimulatory molecules in chronic echinococcus granulosus infection of the human liver

Background: The local immune responses to chronic echinococcal infections in various organs are largely unknown. Since the liver is the most frequently involved organ in such infections in human we aimed to characterize the inflammatory as well as immune cell infiltrate around hydatid cysts in the liver and compared to common inflammatory processes of the liver. Method: Surgical samples from the liver of 21 cystic echinococcosis (CE) patients were studied and the distribution of different types of inflammatory and immune cells were determined by immunohistochemistry. Furthermore, expression levels of costimulatory CTLA4, CD28, CD80 and CD86 molecules were measured at RNA level by PCR. Liver biopsy samples from patients with steatohepatitis (SH, n = 11) and chronic hepatitis (CH, n = 11) were used as non-inflammatory and chronic inflammatory controls, respectively. The composition and density of the inflammatory and immune cell infiltrates have been compared by using morphometry. Results: CD3+ T cells predominated the inflammatory infiltrate in all pathological processes, while in CE samples CD20+ B cells, in CH samples CD68+ macrophages were also frequent. Both myeloperoxidase (MPO) + leukocytes and CD68+ macrophages were found to be significantly decreased in CE as compared to either SH or CH samples. Concerning T cell subtypes, only CD8+ T cells were found to be significantly decreased in SH samples. CD1a + dendritic cells were almost completely missing from CE biopsies unlike in any other sample types. There were no differences detected in the mRNA expression of costimulatory molecules except decreased expression of CD28 in CE samples. Conclusion: In the hydatid lesions of the liver of chronic echinococcal infections T cell-mediated immunity seems to be impaired as compared to other types of chronic inflammatory processes, suggesting an immunosuppressive role for Echinococcus granulosus, which deserve further attentions

Ensemble effects on the reconstruction of attosecond pulses and photoemission time delays

A crucial prerequisite for a detailed interpretation of the experimental results obtained with the most common attosecond spectroscopic techniques is a careful characterization of the attosecond extreme-ultraviolet (XUV) and femtosecond infrared (IR) pulses used in the measurements. A commonly adopted approach is based on the measurement of the spectra of the photoelectrons produced by the interaction of the attosecond pulses with a noble gas in the presence of a delayed IR pulse. Feeding the resulting spectrogram to reconstruction algorithms, it is then possible to retrieve the temporal properties of the XUV and IR pulses. To date, all reconstruction techniques are based on the assumption that the spectrogram is produced by the interaction of a single atom with a two-color (XUV-IR) field. In this work, we numerically investigate the effect of the actual XUV and IR beam spatial distributions, and we analyze their impact on the retrieval of the temporal characteristics of the XUV and IR pulses and on the determination of the photoemission time delays. We show that the impact of the ensemble effects can be severe, leading to notable variation of the photoelectron spectrograms, depending on the ratio between the XUV and IR beam spot sizes and on the IR peak intensity. We demonstrate that the photoemission time delay can be retrieved with great accuracy even in the presence of large deformations of the photoelectron spectrograms by employing suitable reconstruction procedures

Listeria monocytogenes in raw milk and artificially contaminated aliquots

In Italy cow’s raw milk can be sold in vending machine since 2004 and it could be consider a Ready-To-Eat food. However, raw milk was not exempt from biological hazards, in fact Italian legislation dictated that the statement “to be consumed prior boiling” should be posted on vending machines to protect public health. A brief heat treatment of raw milk could be a higher risk for the public health. Therefore, the European legislation imposed that L. monocytogenesmust not exceed the limit of 100 CFU/mL, corresponding to Food Safety Objective (FSO), for non risk group population, and the absence of the pathogen for the immune-compromised individuals and neonates. This study compares the efficiency of the Surface Spread Plate (SSP) and the Most Probable Number (MPN) techniques in recovering L. monocytogenes from artificially contaminated raw milk samples. Moreover L. monocytogenesis enumerated from raw milk samples using the same techniques and the colony count at 30°C is determined in raw milk purchased from vending machines in Northern Italy. The MPN technique was able to recover L. monocytogenes in the artificially contaminated raw milk aliquots at different times of analysis and for different values of inoculums with a major frequency than the SSP technique. The techniques did not show the same efficiency in recovering L. monocytogenes from artificially contaminated raw milk aliquots. The SSP technique did not always detect concentration of the pathogen that exceed the Food Safety Objective (FSO) (absent in 25 g) for the at risk population groups. The food safety of cow’s raw milk contaminated with low level of L. monocytogenescould not be guaranteed for at risk population when consuming such product. Both techniques reported a similar efficiency in the detection of L. monocytogenes from raw milk aliquots for concentration value higher than 100 CFU/mL and thus above the FSO. However the SSP technique proved to be more efficient in detecting Listeriain cow’s raw milk

Antibiotic resistance and resistance genes in Salmonella enterica isolated from pork meat and pig carcasses in Northern Italy.

Introduction- The selective pressure imposed by the widespread use of antimicrobial agents in veterinary medicine may have contributed to the dissemination of multidrug resistant bacterial strains. Moreover, an increase in antibiotic resistance has been reported recently in Salmonella spp. isolated from foods of animal origin. Notoriously, multi-drug resistance in S. enteric can be associated both with specific genes and non-specific resistance mechanisms. Aims- The objectives of this study were to assess the isolation frequency, to determine the serotype and to evaluate the antibiotic resistance of Salmonella spp. isolated from pork meat, pork meat preparations and pig carcasses. Above all S. Enterica isolates were screened to investigate the relationship between the antibiotic resistance towards ampicillin, gentamicin, sulfamethoxazole and tetracycline and the presence of the related genes blaPSE-1 , ant(2’’)-Ia, sul-1,tet(A), tet(B) and tet(G) and marRAB. Materials and methods- S. enteric isolated among 2004 and 2009 from pork meat, pork meat preparations and pig carcasses were analyzed using both phenotypic and molecular methods. Antibiotic susceptibility of the isolates was tested for ampicillin, gentamicin, sulfamethoxazole and tetracycline. Simplex and multiplex PCR protocols were used for detecting the presence of resistance genes. Results- The most frequently isolated serovars were S. Derby and S. Typhimurium. S. Rissen was isolated only from pig carcasses. Most Salmonella isolates were resistant to tetracycline; the antibiotic pattern Am, Sxt and Te was observed in the majority of isolates. Tet(A) and tet(B) genes were mainly detected in S. enterica isolated from pig carcasses. The presence of marRAB was higher in S. Enteric isolated from pork meat. Discussion- The correlation between the resistance phenotypes and the related genes was not always shown; this may be due to the limited selection of investigated genes or to non-specific resistance mechanisms. In our study there was no correlation between the presence of marRAB and resistance towards tetracycline. Conclusions- The high presence of Multi Drug Resistant S. enterica isolated from foodstuff represents a risk for public health, especially when microorganisms are resistant to antibiotics with different mechanisms of action. Moreover, the lack of correlation between the phenotypic resistance and the related selected genes suggests the presence of other specific or non-specific mechanisms involved in the antibiotic resistance phenomenon

New insights into the biology, diagnosis and immune response to Dirofilaria repens in the canine host

: Dogs are the primary host for Dirofilaria repens, therefore it is mandatory to accurately diagnose the canine infection and to expand our current knowledge on parasite biology and the immune response of the infected host for a better prevention.Thus, the aim of the present study was to provide new insights from experimental infections of dogs with D. repens, focusing on the evaluation of: 1) the pre-patent period and 2) the antibody response against D. repens somatic antigens and against the Wolbachia endosymbiont. Briefly, on Day 0, twenty purpose-bred Beagle dogs were experimentally infected with 50 infective larvae (L3) of D. repens. Starting from Day 58 until the last day of the study (Day 281), blood samples were collected on a monthly basis for detection of antibodies against D. repens (Dr) and recombinant Wolbachia surface protein (rWSP) by non-commercial IgG-ELISAs. Additional samples were collected on Days 220, 245 and 281 for the detection of microfilariae (mff) using the modified Knott's test and biomolecular analysis, following two PCR protocols: Gioia et al. (2010; protocol A) and Rishniw et al. (2006- protocol B). The results were analysed by univariate statistical analyses using 2 × 2 contingency tables and K Cohen was calculated to assess the agreement among all the diagnostic techniques. Overall, the outcome of the study revealed that out of the 20 dogs experimentally infected with D. repens, 16 (80 %) were microfilaraemic, 17 (85 %) were positive at DNA detection in the blood, 18 (90 %) had D. repens antibodies and 16 (80 %) had Wolbachia antibodies on the last day of the study. The overall k agreement between Knott's and PCR protocol B was 0.442 (P = 0.0001) and increased throughout the study, reaching 0.828 (P = 0.0001) on Day 281. To the authors knowledge, this is only the second study reporting antibody response to D. repens somatic antigen in experimentally infected dogs. ELISA results showed that an antibody response develops before the onset of patency, and steadily increases with time. Results would suggest that the development of an immunological response to infection could lead to application in epidemiological studies, risk assessment and as an aid in the diagnostic approach in dogs, in particular for early infections without mff

Widespread occurrence of the non-pathogenic hare calicivirus (HaCV Lagovirus GII.2) in captive-reared and free-living wild hares in Europe

The Lagovirus genus comprises both pathogenic viruses as European brown hare syndrome virus (EBHSV- GII.1) and rabbit hemorrhagic disease viruses (RHDV-GI.1 and RHDV2-GI.2), that principally infect European brown hares (Lepus europeaus) and European rabbits (Oryctolagus cuniculus), respectively, causing severe necrotic hepatitis, spleen enlargement and disseminated haemorrhage. This genus includes also non-pathogenic agents, such as rabbit calicivirus (RCV-E1 – GI.3) and the non-pathogenic hare Lagovirus, provisionally named hare calicivirus (HaCV – GII.2). The latter had been identified for the first time in 2012 in the gut contents and faeces of healthy young hares raised in a breeding farm. In this study, we further investigated the presence of HaCV by testing the intestinal tract of 621 wild hares collected between 2010 and 2018 in Northern and Central Italy, and in 2011 in Austria, Germany and Spain. These wild hares were found dead for causes other than EBHS or were healthy hares shot during the hunting season. Forty-three out of 322 hare samples from Italy and 14 out of 299 samples from Austria and Germany were positive for HaCV–GII.2 by RT-PCR using universal primers for lagoviruses and primers specific for HaCV. Sequence analysis of the full capsid protein gene conducted on 12 strains representative of different years and locations indicated that these viruses belong to the same, single cluster as the prototype strain initially identified at the hares’ farm (HaCV_Bs12_1). The relatively high level of genetic variation (88% nt identity) within this cluster suggests HaCVs may have been circulating widely in Europe for some time

New insights into the biology, diagnosis and immune response to Dirofilaria repens in the canine host

Dogs are the primary host for Dirofilaria repens, therefore it is mandatory to accurately diagnose the canine infection and to expand our current knowledge on parasite biology and the immune response of the infected host for a better prevention.Thus, the aim of the present study was to provide new insights from experimental infections of dogs with D. repens, focusing on the evaluation of: 1) the pre-patent period and 2) the antibody response against D. repens somatic antigens and against the Wolbachia endosymbiont. Briefly, on Day 0, twenty purpose-bred Beagle dogs were experimentally infected with 50 infective larvae (L3) of D. repens. Starting from Day 58 until the last day of the study (Day 281), blood samples were collected on a monthly basis for detection of antibodies against D. repens (Dr) and recombinant Wolbachia surface protein (rWSP) by non-commercial IgG-ELISAs. Additional samples were collected on Days 220, 245 and 281 for the detection of microfilariae (mff) using the modified Knott's test and biomolecular analysis, following two PCR protocols: Gioia et al. (2010; protocol A) and Rishniw et al. (2006- protocol B). The results were analysed by univariate statistical analyses using 2 × 2 contingency tables and K Cohen was calculated to assess the agreement among all the diagnostic techniques. Overall, the outcome of the study revealed that out of the 20 dogs experimentally infected with D. repens, 16 (80 %) were microfilaraemic, 17 (85 %) were positive at DNA detection in the blood, 18 (90 %) had D. repens antibodies and 16 (80 %) had Wolbachia antibodies on the last day of the study. The overall k agreement between Knott's and PCR protocol B was 0.442 (P = 0.0001) and increased throughout the study, reaching 0.828 (P = 0.0001) on Day 281. To the authors knowledge, this is only the second study reporting antibody response to D. repens somatic antigen in experimentally infected dogs. ELISA results showed that an antibody response develops before the onset of patency, and steadily increases with time. Results would suggest that the development of an immunological response to infection could lead to application in epidemiological studies, risk assessment and as an aid in the diagnostic approach in dogs, in particular for early infections without mff

First report of Dirofilaria repens infection in a microfilaraemic cat from Romania

The present study describes the first report of Dirofilaria repens infection with the presence of both microfilariae and adult nematodes in a cat from Northeastern Romania. Briefly, a 5-year-old male mixed breed cat was presented to a veterinary clinic in Iasi (Romania), for neutering, in early February 2020. During the surgery, two whitish worms were removed from the internal part of the scrotum. Two adult nematodes, one female and one male, were identified, on the basis of morphological features, as D. repens with whitish, cylindrical bodies, measuring 12.5 cm and 6.5 cm in length, respectively. At histology, the female nematode showed two cavitated structures containing myriads of variably arranged microfilariae. The male had a transversal diameter of 350 μm, a 10 μm thick cuticle and a ridge-period of 10 Μm. multiplex PCR confirmed the diagnosis of D. repens from both nematodes. The Knott's test revealed the presence of microfilariae of D. repens. Routine biochemistry panel was within range with one exception, urea serum level slightly increased. The haematology results revealed an increased number of neutrophils, lymphocytes and eosinophils. The cat had an infection with Otodectes cynotis as well. The cat was discharged with the following therapy recommended: oral doxycycline (10 mg/kg) for 30 days and topical moxidectin, monthly doses. After six months, the Knott's test gave negative results. Further studies should include new insights of D. repens infection in cats concerning its epidemiology, diagnosis and control