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Parvovirus B19 (B19V) is a human pathogenic virus associated with a wide range of clinical conditions. In pregnancy, B19V poses a potential hazard to the fetus as crossing the placental barrier and infecting erythroid progenitor cells in bone marrow and liver, it blocks fetal erythropoiesis leading to profound anemia, hydrops and/or fetal death. The virus is not regarded as a teratogen, however more scientific awareness is emerging on mechanisms and consequences of intrauterine infection and possible sequelae in the neonatal development. Reliable diagnostic procedures and fetal management strategies, including intrauterine transfusion, are established. In spite of being a recognized fetotropic agent possibly leading to fetal loss, testing for B19V is not routinely included in preconception or antenatal screenings, possibly delaying the management of B19V-complicated pregnancies. Continuous advances in B19V research will provide for better diagnostic methods and algorithms, as well as for the development of effective prophylactic interventions and novel therapeutic options. [ABSTRACT FROM AUTHOR]

Parvovirus B19 (B19V) infection is restricted to erythroid progenitor cells (EPCs) of the human bone marrow, leading to transient arrest of erythropoiesis and severe complications mainly in subjects with underlying hematological disorders or with immune system deficits. Currently, there are no specific antiviral drugs for B19V treatment, but identification of compounds inhibiting B19V replication can be pursued by a drug repositioning strategy. In this frame, the present study investigates the activity of hydroxyurea (HU), the only disease-modifying therapy approved for sickle cell disease (SCD), towards B19V replication in the two relevant cellular systems, the UT7/EpoS1 cell line and EPCs. Results demonstrate that HU inhibits B19V replication with EC 50 values of 96.2 µM and 147.1 µM in UT7/EpoS1 and EPCs, respectively, providing experimental evidence of the antiviral activity of HU towards B19V replication, and confirming the efficacy of a drug discovery process by drug repositioning strategy. The antiviral activity occurs in vitro at concentrations lower than those affecting cellular DNA replication and viability, and at levels measured in plasma samples of SCD patients undergoing HU therapy. HU might determine a dual beneficial effect on SCD patients, not only for the treatment of the disease but also towards a virus responsible for severe complications. [ABSTRACT FROM AUTHOR]

We describe a case of chronic fatigue syndrome (CFS) associated to Parvovirus B19 infection where administration of intravenous immunoglobulins (IVIG), previously reported as effective, induced a paradoxical clinical response and increased viral replication. The indication of IVIG administration in the treatment of Parvovirus B19-associated CFS should be carefully reconsidered. [ABSTRACT FROM AUTHOR]

Parvovirus B19 (B19V) is a human ssDNA virus responsible for a wide range of clinical manifestations, still lacking for a specific antiviral therapy. The identification of compounds active against B19V may add therapeutic options to the treatment of B19V infections, that now entirely relies on symptomatic treatments. In the search for compounds possibly inhibiting B19V replication, a particular focus was raised to cidofovir, an acyclic nucleoside phosphonate broadly active against dsDNA viruses. The present study was aimed at evaluating the effect of cidofovir against B19V in two model systems, the UT7/EpoS1 cell line and erythroid progenitor cells (EPC), generated from peripheral blood mononuclear cells. Experiments were carried out at different multiplicity of infections and cidofovir concentrations (0–500 μM) during a course of infection. The effects of cidofovir on B19V replication were assessed by qPCR assays while influence of cidofovir on host cells was measured by cell proliferation and viability assays. Our findings demonstrated that cidofovir has a relevant inhibiting activity on B19V replication within infected UT7/EpoS1, and that the effect on B19V DNA amounts is dose-dependent allowing for the determination of EC 50 and EC 90 values (7.45–41.27 μM, and 84.73–360.7 μM, respectively). In EPCs, that constitute a cellular population close to the natural target cells in bone marrow, the inhibitory effect was demonstrated to a lesser extent, however provoking a significant reduction on B19V DNA amounts at 500 μM (68.2–92.8%). To test infectivity of virus released from EPCs cultured in the presence of cidofovir, cell culture supernatants were used as inoculum for a further course of infection in UT7/EpoS1 cells, indicating a significant reduction in viral infectivity at 500 μM cidofovir. Since the drug did not interfere with the overall cellular DNA synthesis and metabolic activity, the observed effect of cidofovir could be likely related to a specific inhibition of B19V replication. [ABSTRACT FROM AUTHOR]

Candida albicans and Staphylococcus aureus are common human pathogens, frequently isolated independently or co-isolated from bloodstream infections, and able to form dense polymicrobial biofilms on various medical devices resulting in strong resistance to conventionally used antimicrobials. New and innovative approaches are therefore needed to ensure the successful management of biofilm related infections. In this study, a chalcone-based derivative and a polycyclic anthracene-maleimide adduct, previously ascertained by us as inhibitors of C. albicans and S. aureus growths, respectively, were reconsidered in a new perspective by evaluating the efficacy of a combined treatment against a polymicrobial biofilm. Both quantitative and qualitative analyses were carried out to delve into their inhibitory potential on the polymicrobial population. Our results indicate that these newly identified antimicrobials are effective in reducing the biomass of the mixed C. albicans-S. aureus biofilm and the viability of fungal-bacterial cells within the polymicrobial community; in addition, confocal laser scanning microscopy demonstrates that the combined treatment thoroughly modifies the architecture of the dual-species biofilm. [ABSTRACT FROM AUTHOR]

Abstract: Human bocavirus DNA was detected by means of a quantitative, real-time polymerase chain reaction at low levels in the 5.51% of sera obtained from healthy blood donors, suggesting that viral detection in blood is not necessarily associated with disease status. [Copyright &y& Elsevier]

The development of new biomaterials able to favor bone formation and to inhibit bone abnormal resorption is mandatory to face the increasing number of age-related musculo-skeletal disorders. Moreover, the increasing antibiotic resistance of clinically important bacteria, which is among the main causes of implant failure, requires new antimicrobial systems. In this study, we prepared multifunctional materials consisting of hydroxyapatite-zoledronate composite crystals decorated with Ag Nanoparticles (AgNPs). Zoledronate, a potent bisphosphonate widely applied for the treatment of pathologies associated to abnormal bone loss, was incorporated into hydroxyapatite up to about 8 wt%. Loading of poly(ethylenimine) – stabilized AgNPs onto the crystals was promoted by zoledronate functionalization and provoked a significant variation of the values of zeta potential. The results of in vitro tests demonstrate that the multifunctional materials combine the beneficial actions of zoledronate and AgNPs. In fact, they improve osteoblast differentiation and activity, whereas they inhibit osteoclastogenesis and osteoclast differentiation, and significantly hinder the growth of multi-drug resistant Gram positive and Gram negative bacteria. As a consequence, they can be exploited both as antiresorptive agents and as antimicrobial materials able to prevent the development of bone-associated infections. [ABSTRACT FROM AUTHOR]

In this work we developed new antibacterial composite materials using polydopamine (PDA) to trigger the deposition of silver nanoparticles (AgNPs) onto calcium phosphates, namely octacalcium phosphate (OCP) and α-tricalcium phosphate (αTCP). Functionalization of OCP and αTCP with a self-polymerized polydopamine layer was obtained by soaking the calcium phosphates in dopamine solution. The PDA surface of functionalized calcium phosphates (OCPd and αTCPd) promoted the deposition of AgNPs by reducing silver ions when soaked in a silver nitrate solution. The amount of deposited AgNPs can be modulated by varying the concentration of silver nitrate solution and the type of substrate. The results of in vitro tests carried out with osteoblast-like MG63 cells indicate that the combination of AgNPs with OCP provides more biocompatible materials than those obtained using αTCP as substrate. In particular, the study of osteoblast activity and differentiation was focused on the samples OCPdAg5 (silver content = 8.2 wt%) and αTCPdAg5 (silver content = 4.7 wt%), which did not show any cytotoxicity, and compared with those obtained on pure OCP and αTCP. The results demonstrate that the AgNPs loaded materials support osteoblast viability and differentiation, whereas they significantly inhibit the growth of relevant antibiotic-resistant pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Abstract: Results of recent epidemiologic studies suggest the need to reassess the safe upper limit in drinking water of selenium, a metalloid with both toxicological and nutritional properties. Observational and experimental human studies on health effects of organic selenium compounds consumed through diet or supplements, and of inorganic selenium consumed through drinking water, have shown that human toxicity may occur at much lower levels than previously surmised. Evidence indicates that the chemical form of selenium strongly influences its toxicity, and that its biological activity may differ in different species, emphasizing the importance of the few human studies on health effects of the specific selenium compounds found in drinking water. Epidemiologic studies that investigated the effects of selenate, an inorganic selenium species commonly found in drinking water, together with evidence of toxicity of inorganic selenium at low levels in from in vitro and animal studies, indicate that health risks may occur at exposures below the current European Union and World Health Organization upper limit and guideline of 10 and 40μg/l, respectively, and suggest reduction to 1μg/l in order to adequately protect human health. Although few drinking waters are currently known to have selenium concentrations exceeding this level, the public health importance of this issue should not be overlooked, and further epidemiologic research is critically needed in this area. [Copyright &y& Elsevier]

The development of infections still represents a severe problem in orthopedic field. In this work, we developed an anti-microbial and radiopaque calcium phosphate bone cement with a long-lasting inhibitory activity thanks to the addition of gentamicin sulphate-loaded solid lipid microparticles obtained by spray congealing. Cements containing gentamicin both added into cement powder and loaded into microparticles were prepared and characterized and their properties were compared. The results of structural, morphological, mechanical and in vitro characterizations indicate that inclusion of gentamicin into microparticles is a good approach in order to obtain materials able to display a strong inhibition towards the growth of Gram-negative, as well as Gram-positive bacteria and to enhance the viability of osteoblast-like cells. All the compositions have an excellent activity also against clinical isolates, including multi drug resistant phenotypes. In particular, cements containing gentamicin-loaded microparticles display a strong and long-term inhibitory activity. Suitable modification of the liquid/powder ratio provided injectable formulation, whereas addition of BaSO 4 produced radiopacity. All the formulations display good injectability and cohesion, and no evidence of demixing. Image 1 [ABSTRACT FROM AUTHOR]

Snail mucus is an attractive natural substance, which is increasingly used in cosmetic creams and syrups thanks to its emollient, moisturizing, protective and reparative properties. The aim of the present study was to explore the physicochemical properties of chitosan-based films added with snail mucus extracted from Helix Aspersa Muller. To this aim, chitosan films at different content of snail mucus were fabricated by simple solvent casting technique. The results of X-ray diffraction analyses, tensile mechanical tests, Infrared spectroscopy and thermogravimetry demonstrated that snail mucus addition strongly modifies the properties of chitosan films. In particular, it acted like a plasticizer enhancing films extensibility up to ten times and strongly improving their water barrier and bioadhesion properties, with a trend depending on Snail mucus content. Furthermore, it provides the films with antibacterial properties and enhanced cytocompatibility, yielding materials with tailored properties for specific requirements. Unlabelled Image • Snail mucus addition confers functional properties to chitosan films. • Composite films can be stretched up more than ten times with respect to chitosan films. • Bioadhesion and water vapor barrier properties are highly enhanced. • Obtained films are natural materials with antibacterial activity. [ABSTRACT FROM AUTHOR]

Abstract Parvovirus B19 (B19V), a single-stranded DNA virus in the family Parvoviridae , is a human pathogenic virus responsible for a wide range of clinical manifestations. Currently there is no approved antiviral therapy for parvovirus infection. The acyclic nucleoside phosphonate cidofovir (CDV) has been demonstrated to inhibit replication of B19V in vitro. The aim of the present study was to evaluate whether brincidofovir (BCV), a novel lipid conjugate of CDV, could also inhibit B19V replication. Experiments were carried out in erythroid progenitor cells (EPCs) and UT7/EpoS1 cells, infected with B19V and cultured in the presence of different concentrations of BCV and CDV for comparison. The dynamics of viral replication was evaluated by a qPCR-based assay and the extent of inhibition of viral replication exerted by the compounds determined, along with the effect of the compounds on cell viability and cell proliferation rates. Results confirmed that BCV showed significantly higher antiviral activity against B19V compared to CDV in both cell-based systems. For BCV, the calculated EC 50 values were in the range 6.6–14.3 μM in EPCs and 0.22–0.63 μM in UT7/EpoS1 cells. In comparison, the EC 50 values for CDV were >300 μM in EPCs and 16.1 μM in UT7/EpoS1 cells. Concurrently, the effects on cell viability were observed at a much higher concentration of BCV, with calculated CC 50 values in the range 93.4–102.9 μM in EPCs and 59.9–66.8 μM in UT7/Epos1. The antiviral activity was observed specifically with the metabolically active stereoisomer of BCV suggesting that CDV-diphosphate, the metabolite of both BCV and CDV, was the active antiviral. Our results support a selective role for BCV in the inhibition of B19 viral replication. Highlights • Parvovirus B19 (B19V) is a human ssDNA virus, responsible for a wide range of pathologies, lacking a specific antiviral. • We previously showed that the acyclic nucleoside phosphonate cidofovir (CDV) could inhibit B19V at suboptimal activity. • We now show that Brincidofovir (BCV), a lipid conjugate of CDV, exerts a significantly higher antiviral activity on B19V. • A selective activity of BCV was observed both in the myeloblastoid UT7/EpoS1 and in primary erythroid progenitor cells. • A significant activity was observed only with the enantiomer BCV (S), indicating a specific role of its metabolite CDV-PP. [ABSTRACT FROM AUTHOR]

The phytochemical profile, antioxidant activity and α-glucosidase inhibitory activity of Hypericum scruglii Bacchetta, Brullo et Salmeri and Hypericum hircinum L. were analyzed and compared to those of the best-known Hypericum perforatum L. Samples were prepared using three different extraction methods (maceration in 70% ethanol, extraction in MeOH/phosphate buffer and decoction), the influence of which on the metabolic profile and bioactivities are discussed. H . scruglii and H . hircinum extracted in 70% ethanol strongly inhibited α-glucosidase (IC 50 7.25 and 14.05 μg/ml, respectively), which is a valuable enzymatic target for treating metabolic disorders, while H . perforatum was found to be less powerful than the other two species in all the performed biological tests. The phytochemical profile was analyzed by NMR, HPLC-DAD and HPLC-FLD, revealing remarkable differences among the species. In particular, H . scruglii , which is a species endemic to Sardinia Island (Italy), was particularly enriched in two phloroglucinol-derivatives identified by means of 2D NMR and LC/MS/MS experiments as 3-geranyl-1-(2′-methylbutanoyl)-phloroglucinol and 3-geranyl-1-(2′-methylpropanoyl)-phloroglucinol. [ABSTRACT FROM AUTHOR]

A role of cadmium exposure in prostate cancer etiology has been suggested by epidemiologic and laboratory studies, but conclusive evidence on this topic is still lacking. We investigated the relation between cadmium exposure, estimated by determining toenails cadmium levels, and prostate cancer risk in forty patients newly diagnosed with prostate cancer and fifty-eight hospital controls recruited in two provinces from southern and northern Italy. We found an excess cancer risk in subjects in the third and fourth (highest) quartiles of toenail cadmium concentration (odds ratio 1.3 and 4.7, respectively) compared with subjects in the bottom quartile. Results were basically unchanged when limiting the analysis to each province or entering toenail cadmium concentrations as continuous values in the regression model (P =0.004). Despite the limited statistical stability of the point estimates, these findings appear to support the hypothesis that cadmium exposure increases prostate cancer risk. [Copyright &y& Elsevier]

[Display omitted] Gelatin-based films enriched with snail slime are proposed as novel biodegradable and naturally bioadhesive patches for cutaneous drug delivery. Films (thickness range 163–248 μm) were stretchable and they adhered firmly onto the wetted skin, especially those with high amount (70% V/V) of snail slime extract. Fluconazole was selected as model drug and added to films containing the highest amount of snail slime. The presence of Fluconazole (4.53 ± 0.07% w/w) did not modify significantly the mechanical properties, the swelling degree and the bioadhesive performances of the films. Structural investigations demonstrated that the crystalline form III of the drug changed to the amorphous one, forming an amorphous solid dispersion. Moreover, snail slime prevented the drug recrystallization over time. In vitro permeation studies showed that film exhibited a cumulative drug concentration (over 60% in 24 h) similar to that of the control solution containing 20% w/V of ethanol. Fluconazole-loaded gelatin films proved to be effective towards clinical isolates of Candida spp. indicating that the drug maintained its remarkable antifungal activity once formulated into gelatin and snail slime-based films. In conclusion, snail slime, thanks to its peculiar composition, has proved to be responsible of optimal skin adhesion, film flexibility and of the formation of a supersaturating drug delivery system able to increase skin permeation. [ABSTRACT FROM AUTHOR]

In recent decades, synthetic plastic polymers have been the most practical and economical solution for packaging applications due to their low cost, availability, excellent optical, mechanical and barrier properties and resistance against water. However, most of the plastics used for packaging are hardly biodegradable. With a view to a circular economy, the aim of this work focused on the development of a new material made of commercial cellulose derivatives (hydroxypropyl methyl cellulose or carboxymethyl cellulose) mixed with snail mucus extracted from Helix Aspersa Muller. Increasing in Snail Mucus content enhances films elongation and adhesion strength while decreasing water vapor permeability. The cellulose-snail mucus based films are highly transparent but, more interestingly, the mucus confers UV-screening effect. In addition, the composite films exhibit antimicrobial activity against both Gram-positive and Gram-negative bacteria. Furthermore, snail mucus addition to carboxymethyl cellulose strongly decreases films solubility in water. The biodegradation tests indicate that all the films degrade in soil between two and four weeks. The excellent results indicate that these biocomposite films are very good candidate for food packaging. Image 1 • Food packaging films were developed using snail slime and cellulose derivatives, namely HPMC and CMC. • Snail slime strongly improves mechanical and barrier properties of cellulose based films. • Films exhibit good antibacterial activity and high UV–vis light barrier. • Addition of snail slime reduces solubility of CMC based films. [ABSTRACT FROM AUTHOR]

Several strategies have been explored to obtain effective econazole nitrate (ECN) concentrations at the site of application for a prolonged time. In this paper, different gelatin-based film formulations for vaginal application were investigated, containing ECN (10% w/w with respect to gelatin) as pure drug or as drug-solid dispersions (SD). For the production of SD, different polymers were evaluated: polyvinylpyrrolidone (PVP), Soluplus® (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer) and Gelucire® 50/13 (mixture of mono-, di- and triglycerides of fatty acids, esters of PEG 1500 and free PEG). Gelucire®-SD showed the best solubility enhancement, increasing 9.2 times the ECN solubility in pH 4.5 solution respect to pure drug; DSC and XRD analysis confirmed the crystalline form of the drug. XRD results evidenced that all gelatin-based films, containing either the drug or the SD, underwent the topotactic transformation of ECN into crystalline econazole (EC), owing to a strong interaction between the drug and the gelatin. Films containing Gelucire®-based SD displayed lower brittleness and rigidity with respect to the other samples; moreover they demonstrated good structural integrity after 24 h of incubation in the acidic solution (swelling degree of about 350%). Then, Gelucire®-SD based films were compared with the corresponding formulations cross-linked by genipin (2% w/w). The addition of genipin did not interfere with the drug-gelatin interaction. Gelucire®-SD based films showed similar release profiles to neat gelatin films, enhancing the drug release in the first 5 h and controlling the EC release over time, avoiding the use of a crosslinking additive. Finally, gelatin films containing Gelucire® solid dispersion displayed good adhesiveness and anti-Candida activity. Overall, results support the potential use of this film formulation as noncytotoxic EC delivery system for the treatment of vaginal candidiasis. [ABSTRACT FROM AUTHOR]

Quercetin, a flavonoid widely diffused in fruits and vegetables, is known for its good pharmacological qualities, such as anti-oxidant and anti-inflammatory properties. In this work, we loaded quercetin on gelatin films with the aim to develop materials with tailored anti-oxidant, mechanical and stability properties. To this purpose, gelatin films at increasing flavonoid content were prepared using two different solvents, namely H 2 O/EtOH (EtOH films) and DMSO (DMSO films). Quercetin content increased up to about 3.8 and 1.8 wt% in DMSO and EtOH films, respectively. The use of DMSO as solvent prevents the partial regain of collagen triple helix structure during gelling of gelatin sols and results in remarkable extensibility of the films. At variance, EtOH films display X-ray diffraction patterns and DSC plots in agreement with the presence of triple helix structure, and exhibit reduced swelling and increasing mechanical properties on increasing quercetin content. Moreover, their values of denaturation enthalpy indicate the presence of chemical interaction between the flavonoid and gelatin, which can be responsible of their lower quercetin release in PBS in comparison to DMSO films. The flavonoid release is sustained for both series of films and occurs through anchorage to gelatin nanoparticles. Moreover, both DMSO and EtOH functionalized films exhibit relevant anti-oxidant properties, in agreement with their RSA levels, which are comparable to that of pure quercetin. Image 1 • Functionalized gelatin films at different quercetin content. • Quercetin-gelatin films with antioxidant properties. • Quercetin modulates the mechanical and swelling properties of gelatin films. • Sustained release of quercetin from gelatin films. [ABSTRACT FROM AUTHOR]