Cu-based thin rolled foils: relationship among alloy composition, micromechanical and antiviral properties against SARS-CoV-2

The healthcare-associated infections (HAIs) and pandemics caused by multidrug-resistant (MDR) and new-generation pathogens threaten the whole world community. Cu and its alloys have been attracting widespread interest as anti-contamination materials due to the rapid inactivation of MDR-superbugs and viruses. Applying thin Cu-based foils on pre-existing surfaces in hygiene-sensitive areas represents a quick, simple, cost-effective self-sanitising practice. However, the influence of chemical composition and microstructure should be deeply investigated when evaluating the antimicrobial capability and durability of Cu-based materials. The effect of composition on micromechanical and antiviral properties was investigated by comparing Cu15Zn and Cu18Ni20Zn (foil thickness from 13 to 27 μm) with Phosphorous High-Conductivity (PHC) Cu. The influence of recrystallisation annealing of PHC Cu was also investigated. Microstructural characterisation was carried out by optical (OM) and scanning electron (FEG-SEM) microscopy, Energy-dispersive Spectroscopy (EDS) and Electron-Backscattered Diffraction (EBSD). The micromechanical behaviour was assessed by microhardness, microscale abrasion and scratch tests. Cu-based foils were exposed to SARS-CoV-2 for different time points in quasi-dry conditions (artificial sweat solution), evaluating their antiviral capability by quantitative Reverse-Transcriptase Polymerase Chain Reaction (qRT-PCR). Surface morphology, contact angle measurements and Cu release were measured. All Cu-based surfaces completely inactivated SARS-CoV-2 in 10 min: pure Cu was the best option regarding antiviral efficiency, while Cu15Zn showed the best trade-off between micromechanical and antiviral properties.

Evaluation of a rapid Loop Mediated Isothermal Amplification (LAMP) test for the laboratory diagnosis of sexually transmitted infections

Sexually transmitted infections (STIs) have seen a considerable increase in the last years and given the health burden they may represent from both a personal and community perspective, they require surveillance and prevention programmes based on a timely and decentralized diagnosis. In this context, user-friendly rapid molecular tests may represent a good trade-off between diagnostic accuracy, accessibility and affordability. In this study we evaluated the diagnostic performance of a new real-time LAMP (Loop Mediated Isothermal Amplification) method for the rapid detection and differentiation of 7 major sexually transmissible pathogens by analysing real clinical samples (genital and extra-genital matrices) from individuals with suspected STIs. The assay showed good overall diagnostic performances in terms of sensitivity, specificity and concordance with a gold-standard PCR-based molecular method. This assay, not requiring specialised laboratory technicians or expensive instrumentation, but nonetheless capable of guaranteeing accurate results, is within the reach of outpatient settings, obstetrics, and gynaecology clinic, hence ensuring on-field access to early diagnosis.

Cyclosporine A micellar nasal spray characterization and antiviral action against SARS-CoV-2

The upper airways represent the point of entrance from where Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection spreads to the lungs. In the present work, α-tocopheryl-polyethylene-glycol succinate (TPGS) micelles loaded with cyclosporine A (CSA) were developed for nasal administration to prevent or treat the viral infection in the very first phases. The behavior of the micelles in presence of simulated nasal mucus was investigated in terms of stability and mucopenetration rate, evidencing long-term stability and fast diffusion across the glycoproteins matrix. Moreover, the spray characteristics of the micellar formulation and deposition profile in a silicon nasal model were studied using three nasal spray devices. Results allowed to identify the nasal spray pump (BiVax, Aptar) able to provide the wider and uniform deposition of the nasal cavity. The cyclosporine A micelles antiviral activity against SARS-CoV-2 was tested on the Omicron BA.1 variant using Vero E6 cells with protocols simulating treatment before, during and after the infection of the upper airways. Complete viral inactivation was observed for the cyclosporine-loaded micelles while a very low activity was evidenced for the non-formulated drug, suggesting a synergistic activity of the drug and the formulation. In conclusion, this work showed that the developed cyclosporine A-loaded micellar formulations have the potential to be clinically effective against a wide spectrum of coronavirus variants.

The Global Evolutionary History of Orf Virus in Sheep and Goats Revealed by Whole Genomes Data

Orf virus (ORFV) belongs to the genus Parapoxvirus (Poxviridae family). It is the causative agent of contagious ecthyma (CE) that is an economically detrimental disease affecting small ruminants globally. Contagious ecthyma outbreaks are usually reported in intensive breeding of sheep and goats but they have also been reported in wildlife species. Notably, ORFV can infect humans, leading to a zoonotic disease. This study aims to elucidate the global evolutionary history of ORFV genomes in sheep and goats, including the first genomes from Central America in the analyses. In comparison to the last study on ORFV whole genomes, the database now includes 11 more sheep and goat genomes, representing an increase of 42%. The analysis of such a broader database made it possible to obtain a fine molecular dating of the coalescent time for ORFV S and G genomes, further highlighting the genetic structuring between sheep and goat genomes and corroborating their emergence in the latter half of 20th century.

Evaluation of Biofilm Production and Antifungal Susceptibility to Fluconazole in Clinical Isolates of Candida spp. in Both Planktonic and Biofilm Form

Candida spp. are an important opportunistic pathogen that can represent a possible cause of severe infections, especially in immunocompromised individuals. The clinical impact of Candida spp. depends, in part, on the ability to form biofilms, communities of nestled cells into the extracellular matrix. In this study, we compared the biofilm formation ability of 83 strains of Candida spp. isolated from blood cultures and other materials, such as respiratory samples, urine, and exudate, and their sensitivity to fluconazole (FLZ). Strains were divided into tertiles to establish cut-offs to classify isolates as low, moderate, or high biofilm producers (<0.26, 0.266-0.839, >0.839) and biofilms with low, moderate, or high metabolic activity (<0.053, 0.053-0.183, >0.183). A non-linear relationship between biofilm production and metabolic activity was found in C. glabrata and C. tropicalis. In addition, the increase in minimum biofilm eradication concentrations (MBEC50) compared to the Minor Inhibitory Concentration (PMIC) of the planktonic form in Candida spp. confirms the role of biofilm in the induction of resistance to FLZ.

Genomic and Temporal Analysis of Deletions Correlated to qRT-PCR Dropout in N Gene in Alpha, Delta and Omicron Variants

Since the first SARS-CoV-2 outbreak, mutations such as single nucleotide polymorphisms (SNPs) and insertion/deletions (INDELs) have changed and characterized the viral genome sequence, structure and protein folding leading to the onset of new variants. The presence of those alterations challenges not only the clinical field but also the diagnostic demand due to failures in gene detection or incompleteness of polymerase chain reaction (PCR) results. In particular, the analysis of understudied genes such as N and the investigation through whole-genome next generation sequencing (WG-NGS) of regions more prone to mutate can help in the identification of new or reacquired mutations, with the aim of designing robust and long-lasting primers. In 48 samples of SARS-CoV-2 (including Alpha, Delta and Omicron variants), a lack of N gene amplification was observed in the genomes analyzed through WG-NGS. Three gene regions were detected hosting the highest number of SNPs and INDELs. In several cases, the latter can interfere deeply with both the sensitivity of diagnostic methodologies and the final protein folding. The monitoring over time of the viral evolution and the reacquisition among different variants of the same mutations or different alterations within the same genomic positions can be relevant to avoid unnecessary consumption of resources.

An Enhanced Dissolving Cyclosporin-A Inhalable Powder Efficiently Reduces SARS-CoV-2 Infection In Vitro

This work illustrates the development of a dry inhalation powder of cyclosporine-A for the prevention of rejection after lung transplantation and for the treatment of COVID-19. The influence of excipients on the spray-dried powder's critical quality attributes was explored. The best-performing powder in terms of dissolution time and respirability was obtained starting from a concentration of ethanol of 45% (v/v) in the feedstock solution and 20% (w/w) of mannitol. This powder showed a faster dissolution profile (Weibull dissolution time of 59.5 min) than the poorly soluble raw material (169.0 min). The powder exhibited a fine particle fraction of 66.5% and an MMAD of 2.97 µm. The inhalable powder, when tested on A549 and THP-1, did not show cytotoxic effects up to a concentration of 10 µg/mL. Furthermore, the CsA inhalation powder showed efficiency in reducing IL-6 when tested on A549/THP-1 co-culture. A reduction in the replication of SARS-CoV-2 on Vero E6 cells was observed when the CsA powder was tested adopting the post-infection or simultaneous treatment. This formulation could represent a therapeutic strategy for the prevention of lung rejection, but is also a viable approach for the inhibition of SARS-CoV-2 replication and the COVID-19 pulmonary inflammatory process.

SARS-CoV-2 Co-Infection in Immunocompromised Host Leads to Generation of Recombinant Strain

Recombination related to co-infection is a huge driving force in determining the virus genetic variability, particularly in conditions of partial immune control leading to prolonged infection. Here we characterized a distinctive mutational pattern, highly suggestive of Delta-Omicron double infection, in a lymphoma patient. The specimen was characterized through a combined approach, analyzing the results of deep sequencing in primary sample, viral culture and plaque assay. Bioinformatic analysis on the sequences deriving from the primary sample supports the hypothesis of a double viral population within the host. Plaque assay on viral culture led to the isolation of a recombinant strain deriving from Delta and Omicron lineages, named XS, which virtually replaced its parent lineages within a single viral propagation. It is impossible to establish whether the recombination event happened within the host or in vitro, however it is important to monitor co-infections, especially in the exceptional intra-host environment of immunocompromised patients, as strong driving forces of viral evolution.

Omicron Sub-Lineage BA.5 and Recombinant XBB Evasion from Antibody Neutralisation in BNT162b2 Vaccine Recipients

The recent emergence of a number of new SARS-CoV-2 variants resulting from recombination between two distinct parental lineages or sub-lineages within the same lineage has sparked the debate regarding potential enhanced viral infectivity and immune escape. Among these, XBB, recombinant of BA.2.10 and BA.2.75, has caused major concern in some countries due to its rapid increase in prevalence. In this study, we tested XBB escape capacity from mRNA-vaccine-induced (BNT162b2) neutralising antibodies compared to B.1 ancestral lineage and another co-circulating variant (B.1.1.529 BA.5) by analysing sera collected 30 days after the second dose in 92 healthcare workers. Our data highlighted an enhanced and statistically significant immune escape ability of the XBB recombinant. Although these are preliminary results, this study highlights the importance of immune escape monitoring of new and forthcoming variants and of the reformulation of existing vaccines.

Mutational induction in SARS-CoV-2 major lineages by experimental exposure to neutralising sera

The ongoing evolution of SARS-CoV-2 and the emergence of new viral variants bearing specific escape mutations responsible for immune evasion from antibody neutralisation has required a more accurate characterisation of the immune response as one of the evolutive forces behind viral adaptation to a largely immunised human population. In this work, culturing in the presence of neutralising sera vigorously promoted mutagenesis leading to the acquisition of known escape mutations on the spike as well as new presumptive escape mutations on structural proteins whose role as target of the neutralizing antibody response might have been thus far widely neglected. From this perspective, this study, in addition to tracing the past evolution of the species back to interactions with neutralising antibody immune response, also offers a glimpse into future evolutive scenarios.

Organic Electrochemical Transistors as Versatile Tool for Real-Time and Automatized Viral Cytopathic Effect Evaluation

In-vitro viral studies are still fundamental for biomedical research since studying the virus kinetics on cells is crucial for the determination of the biological properties of viruses and for screening the inhibitors of infections. Moreover, testing potential viral contaminants is often mandatory for safety evaluation. Nowadays, viral cytopathic effects are mainly evaluated through end-point assays requiring dye-staining combined with optical evaluation. Recently, optical-based automatized equipment has been marketed, aimed at the real-time screening of cell-layer status and obtaining further insights, which are unavailable with end-point assays. However, these technologies present two huge limitations, namely, high costs and the possibility to study only cytopathic viruses, whose effects lead to plaque formation and layer disruption. Here, we employed poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (Pedot:Pss) organic electrochemical transistors (OECTs) for the real-time, electrical monitoring of the infection of cytolytic viruses, i.e., encephalomyocarditis virus (EMCV), and non-cytolytic viruses, i.e., bovine coronavirus (B-CoV), on cells. OECT data on EMCV were validated using a commercially-available optical-based technology, which, however, failed in the B-CoV titration analysis, as expected. The OECTs proved to be reliable, fast, and versatile devices for viral infection monitoring, which could be scaled up at low cost, reducing the operator workload and speeding up in-vitro assays in the biomedical research field.

Correlating qRT-PCR, dPCR and Viral Titration for the Identification and Quantification of SARS-CoV-2: A New Approach for Infection Management

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in Wuhan, China, in late 2019 and is the causative agent of the coronavirus disease 2019 (COVID-19) pandemic. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) represents the gold standard for diagnostic assays even if it cannot precisely quantify viral RNA copies. Thus, we decided to compare qRT-PCR with digital polymerase chain reaction (dPCR), which is able to give an accurate number of RNA copies that can be found in a specimen. However, the aforementioned methods are not capable to discriminate if the detected RNA is infectious or not. For this purpose, it is necessary to perform an endpoint titration on cell cultures, which is largely used in the research field and provides a tissue culture infecting dose per mL (TCID50/mL) value. Both research and diagnostics call for a model that allows the comparison between the results obtained employing different analytical methods. The aim of this study is to define a comparison among two qRT-PCR protocols (one with preliminary RNA extraction and purification and an extraction-free qRT-PCR), a dPCR and a titration on cell cultures. The resulting correlations yield a faithful estimation of the total number of RNA copies and of the infectious viral burden from a Ct value obtained with diagnostic routine tests. All these estimations take into consideration methodological errors linked to the qRT-PCR, dPCR and titration assays.

Comparison of glomerular filtration rate estimates vs. 24-h creatinine clearance in HIV-positive patients

BACKGROUND

Guidelines for kidney function monitoring and antiretroviral drug dosing are available and respectively refer to glomerular filtration rate and creatinine clearance (CrCl).

OBJECTIVE

The aim of the study was to compare kidney function estimates vs. measured 24-h CrCl in HIV-infected subjects.

METHODS

A cross-sectional design was used, with comparison of Cockcroft-Gault (CG), original and simplified modification of diet in renal disease (MDRD) equations vs. measured 24-h CrCl. Subjects were HIV-infected, 18-70 years old, without pre-existing kidney disease.

RESULTS

Results are presented as mean (+/-standard deviation), unless otherwise stated. The study population consisted of 90 patients, of whom 71% were male, with a mean age of 45 years (+/-6.5 years). At the time of evaluation, the mean body mass index was 23 (+/-3.3); mean serum creatinine was 0.91 mg/dL (+/-0.2 mg/dL); and mean blood urea nitrogen (BUN) was 34.7 mg/dL (+/-10.6 mg/dL). Differences between paired methods were all significant (P<0.00001), except between CG and simplified MDRD (P=0.21; Pearson r=0.81). In univariate analysis, male gender, CD4 nadir, hepatitis B virus coinfection, BUN and current CD4 cell count showed a significant positive correlation (P<0.2) with the difference between measured 24-h CrCl and either CG or simplified MDRD estimates. In multivariate analysis, only BUN showed a significant positive correlation (P<0.05).

CONCLUSIONS

Estimates were lower than the measurements of 24-h CrCl. Original MDRD estimates were lower than those with other equations. CG and simplified MDRD estimates showed a satisfactory correlation.

One-month exposure to soy isoflavones did not induce the ability to produce equol in postmenopausal women

OBJECTIVE

As more and more postmenopausal women are taking soy isoflavone supplementation for relieving menopausal symptoms, we investigated the impact of chronic exposure on their bioavailability, with focus on achievable plasma concentrations and potential stimulation of the capacity to produce equol.

SUBJECTS

A total of 12 Caucasian postmenopausal women.

INTERVENTION

Volunteers ingested 100 mg isoflavones/day (aglycone equivalents, in cereal bars and yoghurts) for 1 month. Plasma concentrations of metabolites at 2, 4, 6, 8, 10, 12 and 24 h postdose, as well as urinary excretion in fractions over 36 h were compared between days 1 and 30.

RESULTS

Similar plasma kinetic curves were obtained at day 1 and day 30 for genistein and daidzein. Maximum plasma concentrations were 1.68+/-0.68 micromol/l on day 1 compared to 2.27+/-0.76 micromol/l on day 30 for daidzein (P=0.056), and 3.88+/-1.50 micromol/l on day 1 compared to 5.30+/-2.38 micromol/l on day 30 for genistein (P=0.091). Urinary excretion of daidzein and genistein did not differ significantly between days 1 and 30. Maximum plasma concentration of equol increased significantly from 0.31+/-0.27 to 0.99+/-0.51 micromol/l for equol-producer volunteers (P=0.046). However, the seven volunteers who were classified as non-equol producers on day 1 did not acquire the ability to produce equol after 1-month exposure.

CONCLUSIONS

Chronic exposure to isoflavones in postmenopausal women resulted in plasma concentrations as high as 2.5-5 micromol/l of each isoflavone, but did not induce the ability to produce equol.

Energy value of a low-digestible carbohydrate, NUTRIOSE FB, and its impact on magnesium, calcium and zinc apparent absorption and retention in healthy young men

BACKGROUND

Long-term consumption of imbalanced diets, poor in dietary fibres, resulted in the prevalence of several nutritional pathologies. However, low digestible carbohydrates (LDC) have many beneficial effects, especially on energy intake, digestive physiology, and mineral absorption.

AIM OF THE STUDY

To determine the digestive effects of a LDC, called NUTRIOSE FB, its metabolisable energy (ME) value, and its effects on mineral absorption in humans.

METHODS

Ten healthy young men were fed for 31 d periods a maintenance diet supplemented with either dextrose or the LDC at a level of 100 g DM/d, in six equal doses per d according to a cross-over design. After a 20 d adaptation period, food intake was determined for 11 days using the duplicate meal method, and faeces and urine were collected for 10 d for further analyses.

RESULTS

Ingestion of the LDC did not cause severe digestive disorders, except excessive gas emission, and flatulence and slight abdominal pain in some subjects for intakes above 50 g DM/d. Wet and dry stool outputs increased by 45 and 70%, respectively (P<0.02). In vitro enzymatic digestibility of the LDC was 15 (SD 1.5) %, and 9.2 (SD 8.3) % of the LDC was excreted in faeces (P<0.001). The ME value of the LDC was 14.1 (SD 2.3) kJ/g DM, that is 14 % less than the tabulated values of sucrose and starch. Its net energy value (NEV), estimated using three prediction equations, was 8.7, 8.9, and 11.4 kJ/g DM. Ingestion of the LDC significantly increased the relative apparent absorption of Mg, and Mg retention by 67% and 31 mg/d, respectively, tended to increase Ca apparent absorption (P=0.110) and Ca retention (P=0.059), but did not significantly alter Zn parameters.

CONCLUSION

NUTRIOSE FB can be used as a "bulking" agent, and substituted up to 50 g/d for usual maltodextrins without causing digestive disorders in healthy subjects. It would reduce intestinal transit disorders and energy intake, and improve magnesium and calcium absorption and retention.

Net energy value of two low-digestible carbohydrates, Lycasin HBC and the hydrogenated polysaccharide fraction of Lycasin HBC in healthy human subjects and their impact on nutrient digestive utilization

The metabolizable energy content of low-digestible carbohydrates does not correspond with their true energy value. The aim of the present study was to determine the tolerance and effects of two polyols on digestion and energy expenditure in healthy men, as well as their digestible, metabolizable and net energy values. Nine healthy men were fed for 32 d periods a maintenance diet supplemented either with dextrose, Lycasin HBC (Roquette Frères, Lestrem, France), or the hydrogenated polysaccharide fraction of Lycasin HBC, at a level of 100 g DM/d in six equal doses per d according to a 3 x 3 Latin square design with three repetitions. After a 20 d progressive adaptation period, food intake was determined for 12d using the duplicate meal method and faeces and urine were collected for 10 d for further analyses. Subjects spent 36 h in one of two open-circuit whole-body calorimeters with measurements during the last 24h. Ingestion of the polyols did not cause severe digestive disorders, except excessive gas emission, and flatulence and gurgling in some subjects. The polyols induced significant increases in wet (+45 and +66% respectively, P<0.01) and dry (+53 and +75 % respectively, P<0.002) stool weight, resulting in a 2% decrease in dietary energy digestibility (P<0.001). They resulted also in significant increases in sleeping (+4.1%, P<0.03) and daily energy expenditure (+2.7 and +2.9% respectively, P<0.02) compared with dextrose ingestion. The apparent energy digestibility of the two polyols was 0.82 and 0.79 respectively, their metabolizable energy value averaged 14.1 kJ/g DM, and their net energy value averaged 10.8 kJ/g DM, that is, 35 % less than those of sucrose and starch.

Age-related changes in plasma lycopene concentrations, but not in vitamin E, are associated with fat mass

The aim of the present study was to assess the influence of age on plasma concentration of alpha-tocopherol, retinol and carotenoids with a special attention paid to natural differences in body composition. Forty healthy subjects were recruited: twenty were less than 35 years old and twenty above 60 years old. Males and females were equally represented in each age group. Subjects were kept in energy balance and received controlled diets for 36 h. Fat mass and fat-free mass were determined with the (18)0-enriched water dilution technique. Plasma vitamins A and E, and carotenoid levels were determined after 12 h fasting and were shown to be similar in women and men. Plasma alpha-tocopherol concentration increased with age (+44 % elderly v. young), and correlated with % fat mass and plasma cholesterol. After adjustment for plasma cholesterol, the effect of age and % fat mass disappeared. In contrast, plasma lycopene level was 2-fold lower in the elderly than in the young group, and was inversely correlated with fat mass. When lycopene values were adjusted for fat mass, the effect of age disappeared. These results suggest that plasma levels of vitamin E and lycopene differed in the two age groups and that differences in plasma cholesterol and fat mass might participate in such an effect. Short-term vitamin intake did not appear to influence plasma vitamin concentrations.