Ready-to-eat sandwiches as source of pathogens endowed with antibiotic resistance and other virulence factors

The aim of this study was to evaluate and characterize the bacterial load present in twenty-four Ready-To-Eat (RTE) sandwiches, purchased at refrigerated vending machines and supermarkets in the province of Modena (Italy). We isolated 54 bacterial strains, including pathogens of interest in food safety, such as Listeria, Staphylococcus, Enterococcus, Yersinia, Aeromonas and Acinetobacter spp. Phenotypic tests have been performed on these pathogens to detect the presence of virulence factors, such as gelatinase production and hemolytic capability. To test their antibiotic resistance features, the minimum inhibitory concentration (MIC) against eight commonly used antibiotics (Amikacin, Ciprofloxacin, Ampicillin, Oxacillin, Imipenem, Tetracycline, Erythromycin and Vancomycin) was also evaluated. The results showed that among the 54 isolates, fifty percent (50%) belonged to harmless microorganisms (Leuconostoc and Lactococcus), whereas the remaining fifty percent (50%) included pathogenic bacteria (Listeria ivanovii, Listeria monocytogenes, Staphylococcus aureus, Yersinia, and Citrobacter spp.), species responsible for pathologies often difficult to treat due to the presence of antibiotic resistance features. This study demonstrates the importance of thorough controls, both during the production and marketing of RTE food like sandwiches, to avoid reaching the infectious load and the onset of pathologies, particularly dangerous for old and immunocompromised patients

Dietary fluoride intake by children: When to use a fluoride toothpaste?

Fluoride is recommended for its cariostatic effect, but excessive fluoride intake may have health risks. Increased prevalence of dental fluorosis in areas with low fluoride content in drinking water has been attributed to the inappropriate excessive intake of fluoride supplements (tablets and drops) and toothpaste ingestion. The aim of the present study was to estimate the fluoride intake and the risk of fluorosis in children (6 months–6 years) in the Castelli Romani area (province of Rome, Italy), which is volcanic, therefore with a higher concentration of fluorine. Measurements of the fluoride content in drinking water, mineral waters, vegetables and commercial toothpaste for children were performed. The fluoride concentrations of all samples were determined using a Fluoride Ion Selective Electrode (GLP 22, Crison, Esp). Data were analyzed by descriptive statistics. Differences between samples were determined by Student’s t-test. The fluoride content in tap water samples collected from public sources averaged from 0.35 to 1.11 ppm. The Pavona area showed the highest content of fluoride with respect to the others (p ≤ 0.05). The fluoride content in mineral water samples averaged from 0.07 to 1.50 ppm. The fluoride content of some vegetables showed increased mean values when compared to control vegetables (p ≤ 0.05). Within the limitations of the present study, considerations should be made when prescribing fluoride toothpaste for infants (6 months–4 years) in the areas with high fluoride content, because involuntary ingestion is consistent

Neonatal respiratory distress syndrome: are risk factors the same in preterm and term infants?

Objective: To analyze respiratory distress syndrome (RDS) incidence and risk factors at different gestational age. Methods: We considered data from 321 327 infants born in Lombardy, a Northern Italian Region. We computed multivariate analysis to identify risk factors for RDS by dividing infants in early- and moderate-preterm, late-preterm and term infants. Results: Low-birth weight is the main risk factor for RDS, with higher odds ratio in term births. The risk was higher in infants delivered by cesarean section and in male, for all gestational age. Pathological course of pregnancy resulted in increased risk only in late-preterm and term infants. Maternal age and multiple birth were not associated with increased risk in any group. Babies born at term after assisted conception were at higher risk of RDS. Conclusion: Our analysis suggests as some risk factors do not influence RDS incidence in the same way at different gestational age

The Evidence for a Pentaquark Signal and Kinematic Reflections

Several recent experiments have reported evidence for a narrow baryon resonance with positive strangeness ($\Theta^+$) at a mass of 1.54 GeV/$c^2$. Baryons with $S=+1$ cannot be conventional $qqq$ states and the reports have thus generated much theoretical speculation about the nature of possible $S=+1$ baryons, including a 5-quark, or pentaquark, interpretation. We show that narrow enhancements in the $K^+n$ effective mass spectrum can be generated as kinematic reflections resulting from the decay of mesons, such as the $f_2(1275)$, the $a_2(1320)$ and the $\rho_3(1690)$.Comment: 4 pages, 4 figure

Physical and chemical mechanisms involved in adhesion of orthodontic bonding composites: in vitro evaluations

BackgroundBond strength of orthodontic composite is strongly influenced by molecular and structural mechanisms. Aim of this in vitro study was to compare bond strength of light-cure orthodontic composites by measuring debonding forces and evaluating locations of bond failure. Investigations on chemical compositions clarified adhesive behaviors and abilities, exploring effects of ageing processes in this junction materials.MethodsTwelve enamel discs, from human premolars, were randomly coupled to one orthodontic adhesive system (Transbond XT (TM) 3 M UNITEK, USA, Light-Cure Orthodontic Paste, LEONE, Italy and Bisco Ortho Bracket Paste LC, BISCO, Illinois) and underwent to Shear Bond Strength test. Metallic brackets were bonded to twenty-seven human premolar, with one of the adhesive systems, to quantify, at FE-SEM magnifications, after debonding, the residual material on enamel and bracket base surfaces. Raman Spectroscopy analysis was performed on eight discs of each composites to investigate on chemical compositions, before and after accelerated aging procedures in human saliva and sugary drink.ResultsOrthodontic adhesive systems showed similar strength of adhesion to enamel. The breakage of adhesive-adherent bond occurs in TXT at enamel-adhesive interface while in Bisco and Leone at adhesive-bracket interface. Accelerated in vitro aging demonstrated good physical-chemical stability for all composites, Bisco only, was weakly contaminated with respect to the other materials.ConclusionA similar, clinically adequate and acceptable bond strength to enamel for debonding maneuvers was recorded in all orthodontic adhesive systems under examination. No significant chemical alterations are recorded, even in highly critical situations, not altering the initial mechanical properties of materials

Flux Tube Zero-Point Motion, Hadronic Charge Radii, and Hybrid Meson Production Cross Sections

Flux tube zero-point motion produces quark displacements transverse to the flux tube which make significant contributions to hadronic charge radii. In heavy quark systems, these contributions can be related by Bjorken's sum rule to the rates for semileptonic decay to hybrid mesons. This connection can be generalized to other leptoproduction processes, where transverse contributions to elastic form factor slopes are related to the cross sections for the production of the associated hybrid states. I identify the flux tube overlap integral responsible for these effects as the strong QCD analogue of the Sudakov form factor of perturbative QCD.Comment: 16 pages, revised to clarify some points and to improve and correct the notation for the flux tube wave function

Semi-Classical Description of Antiproton Capture on Atomic Helium

A semi-classical, many-body atomic model incorporating a momentum-dependent Heisenberg core to stabilize atomic electrons is used to study antiproton capture on Helium. Details of the antiproton collisions leading to eventual capture are presented, including the energy and angular momentum states of incident antiprotons which result in capture via single or double electron ionization, i.e. into [He$^{++}\,\bar p$ or He$^{+}\,\bar p$], and the distribution of energy and angular momentum states following the Auger cascade. These final states are discussed in light of recently reported, anomalously long-lived antiproton states observed in liquid He.Comment: 15 pages, 9 figures may be obtained from authors, Revte

Photo-- and Electroproduction of JPC=1−+J^{PC}=1^{-+} exotics

We estimate the kinematic dependence of the exclusive photo-- and electroproduction of $J^{PC}=1^{-+}$ exotic mesons due to $\pi$ exchange. We show that the kinematic dependence is largely independent of the exotic meson form factor, which is explicitly derived for a $1^{-+}$ isovector hybrid meson in the flux-tube model of Isgur and Paton. The relevance to experiments currently planned at Jefferson Lab is indicated.Comment: 15 pages, latex, epsf, 8 postscript figure

How COVID-19 has fundamentally changed clinical research in global health

COVID-19 has had negative repercussions on the entire global population. Despite there being a common goal that should have unified resources and efforts, there have been an overwhelmingly large number of clinical trials that have been registered that are of questionable methodological quality. As the final paper of this Series, we discuss how the medical research community has responded to COVID-19. We recognise the incredible pressure that this pandemic has put on researchers, regulators, and policy makers, all of whom were doing their best to move quickly but safely in a time of tremendous uncertainty. However, the research community\u27s response to the COVID-19 pandemic has prominently highlighted many fundamental issues that exist in clinical trial research under the current system and its incentive structures. The COVID-19 pandemic has not only re-emphasised the importance of well designed randomised clinical trials but also highlighted the need for large-scale clinical trials structured according to a master protocol in a coordinated and collaborative manner. There is also a need for structures and incentives to enable faster data sharing of anonymised datasets, and a need to provide similar opportunities to those in high-income countries for clinical trial research in low-resource regions where clinical trial research receives considerably less research funding