194 research outputs found
Effective elimination of Staphylococcal contamination from hospital surfaces by a bacteriophage-probiotic sanitation strategy: a monocentric study.
Persistent contamination of hospital surfaces and antimicrobial resistance (AMR) are recognized major causes of healthcare-associated infections (HAI). We recently showed that a probiotic-based sanitation (PCHS) can stably decrease surface pathogens and reduce AMR and HAIs. However, PCHS action is slow and non-specific. By contrast, bacteriophages have been proposed as a decontamination method as they can rapidly attack specific targets, but their routine application has never been tested. Here we analyzed the feasibility and effectiveness of phage addition to PCHS sanitation, aiming to obtain a rapid and stable abatement of specific pathogens in the hospital environment. Staphylococcal contamination in the bathrooms of General Medicine wards was analyzed, being such areas the most contaminated and Staphylococci the most prevalent bacteria in such settings. Results showed that a daily phage application by nebulization induced a rapid and significant decrease of Staphylococcus spp. load on treated surfaces, up to 97% more than PCHS alone (p<0.001), suggesting that such system might be considered as a part of prevention and control strategies, to counteract outbreaks of specific pathogens and prevent associated infections
Decoding of Multiple Wrist and Hand Movements Using a Transient EMG Classifier
: The design of prosthetic controllers by means of neurophysiological signals still poses a crucial challenge to bioengineers. State of the art of electromyographic (EMG) continuous pattern recognition controllers rely on the questionable assumption that repeated muscular contractions produce repeatable patterns of steady-state EMG signals. Conversely, we propose an algorithm that decodes wrist and hand movements by processing the signals that immediately follow the onset of contraction (i.e., the transient EMG). We collected EMG data from the forearms of 14 non-amputee and 5 transradial amputee participants while they performed wrist flexion/extension, pronation/supination, and four hand grasps (power, lateral, bi-digital, open). We firstly identified the combination of wrist and hand movements that yielded the best control performance for the same participant (intra-subject classification). Then, we assessed the ability of our algorithm to classify participant data that were not included in the training set (cross-subject classification). Our controller achieved a median accuracy of ~96% with non-amputees, while it achieved heterogeneous outcomes with amputees, with a median accuracy of ~89%. Importantly, for each amputee, it produced at least one acceptable combination of wrist-hand movements (i.e., with accuracy >85%). Regarding the cross-subject classifier, while our algorithm obtained promising results with non-amputees (accuracy up to ~80%), they were not as good with amputees (accuracy up to ~35%), possibly suggesting further assessments with domain-adaptation strategies. In general, our offline outcomes, together with a preliminary online assessment, support the hypothesis that the transient EMG decoding could represent a viable pattern recognition strategy, encouraging further online assessments
Pathogen Control in the Built Environment: A Probiotic-Based System as a Remedy for the Spread of Antibiotic Resistance
The high and sometimes inappropriate use of disinfectants and antibiotics has led to alarming levels of Antimicrobial Resistance (AMR) and to high water and hearth pollution, which today represent major threats for public health. Furthermore, the current SARS-CoV-2 pandemic has deeply influenced our sanitization habits, imposing the massive use of chemical disinfectants potentially exacerbating both concerns. Moreover, super-sanitation can profoundly influence the environmental microbiome, potentially resulting counterproductive when trying to stably eliminate pathogens. Instead, environmentally friendly procedures based on microbiome balance principles, similar to what applied to living organisms, may be more effective, and probiotic-based eco-friendly sanitation has been consistently reported to provide stable reduction of both pathogens and AMR in treated-environments, compared to chemical disinfectants. Here, we summarize the results of the studies performed in healthcare settings, suggesting that such an approach may be applied successfully also to non-healthcare environments, including the domestic ones, based on its effectiveness, safety, and negligible environmental impact
A selective cellulose/hemicellulose green solvents extraction from buckwheat chaff
A two-phase extraction process was adopted to obtain cellulose and hemicellulose from buckwheat chaff by using green solvents. We are proposing a combination of propylene carbonate (PC) and ionic liquids (ILs) in a 1:5 ratio. We compared the first-generation ILs 1-butyl-2,3-dimethylimidazolium chloride (BdmimCl), and 1-butyl-3-methyl imidazolium acetate (BmimAc) with respect to the tetrabutyl ammonium acetate (TBAAc). The cellulose and hemicellulose were, firstly, extracted into the PC/IL mixture and subsequently precipitated by water addition. All precipitate materials were analysed by FTIR-ATR and TGA, while the organic phase and the supernatant after water addition were analysed by using self-diffusion NMR. The PC green co-solvent was proven to be an exceptional candidate to replace dimethyl sulfoxide. The highest amount of precipitate material after water addition was obtained with PC-BmimAc, while PC-TBAAc was showing the highest cellulose/hemicellulose selectivity. Furthermore, a preferential interaction of the supernatant cellulose residue with PC or acetate was observed by self-diffusion NMR
Valorization of cigarette butts for synthesis of levulinic acid as top value-added chemicals
Unprecedented in the literature, levulinic acid (LA), one of the top value-added intermediates of chemical industry, is obtained from cigarette butts as cellulose feedstock by means of a one-pot hydrothermal process carried out at 200 °C for 2 h and catalysed by phosphoric acid. The protocol avoids the use of more aggressive and toxic H2SO4 and HCl, that are generally employed on several cellulose sources (e.g. sludge paper), thus minimizing corrosion phenomena of plants. Neither chemical pre-treatment of butts nor specific purification procedure of LA are required. Notably, by simply modifying acid catalyst (e.g. using CH3COOH), another top value-added fine chemical such as 5-hydroxymethylfuraldehyde (HMF) is obtained, thus widening the scope of the method. Being cigarette filters a waste available in quantities of megatonnes per year, they represent an unlimited at no cost source of cellulose, thus enabling the up-scale to an industrial level of LA production
Deep control of linear oligomerization of glycerol using lanthanum catalyst on mesoporous silica gel
The valorization of glycerol (1), a waste of biodiesel production of Fatty Acid Methyl Esters (FAMEs), adopting a âgreenâ approach, represents an important goal of sustainable chemistry. While the polymerization of 1 to hyperbranched oligomers is a well-established process, the linear analogues are difficult to obtain. In this context, we explore the reaction without the solvent of heterogeneous hybrid La(III)O-KIT-6 catalyst (2), which is based on lanthanum oxide on mesoporous silica gel, showing a superior linear selectivity compared to most of the analogous catalysts recently reported
HHV-6A infection and systemic sclerosis: Clues of a possible association
Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, excessive extracellular matrix deposition, and fibrosis of the skin and internal organs. Several infectious agents, including human herpesvirus-6 (HHV-6), have been suggested as possible triggering factors, but a direct association is still missing. We characterized 26 SSc patients for the presence of HHV-6 in tissues and blood, the anti-HHV-6 response, HLA-G plasma levels, and KIR typing. Given the prominent role of endothelial cells (EC) in SSc pathogenesis, along with HHV-6 tropism for EC, we also investigated the expression of pro-fibrosis factors in HHV-6 infected EC. Results showed the presence of HHV-6A in skin biopsies, and an increased virus load was associated with disease severity and poor natural killer (NK) response against the virus, particularly in subjects exhibiting a KIR2 phenotype. HLA-G plasma levels were significantly higher in HHV- 6A/B-KIR2 positive SSc patients and in vitro HHV-6A infection-induced pro-fibrosis factors expression in EC, supporting its role in the development of the fibrosing process. Our data suggest an association between virus infection/reactivation and disease, opening the way to future studies to understand the mechanisms by which HHV-6A might contribute to the multifactorial pathogenesis of SSc
Photoreduction of Carbon Dioxide to Formic Acid in Aqueous Suspension: A Comparison between Phthalocyanine/TiO2 and Porphyrin/TiO2 Catalysed Processes
Composite materials prepared by loading polycrystalline TiO2 powders with lipophilic highly branched Cu(II)- and metal-free phthalocyanines or porphyrins, which have been used in the past as photocatalysts for photodegradative processes, have been successfully tested for the efficient photoreduction of carbon dioxide in aqueous suspension affording significant amounts of formic acid. The results indicated that the presence of the sensitizers is beneficial for the photoactivity, confirming the important role of Cu(II) co-ordinated in the middle of the macrocycles. A comparison between Cu(II) phthalocyanines and Cu(II) porphyrins indicated that the Cu(II)- phthalocyanine sensitizer was more efficient in the photoreduction of CO2 to formic acid, probably due to its favorable reduction potential
Concerning synthesis of new biobased polycarbonates with curcumin in replacement of bisphenol a and recycled diphenyl carbonate as example of circular economy
Curcumin (CM) is a natural polyphenol well-known for its antioxidant and pharmaceutical properties, that can represent a renewable alternative to bisphenol A (BPA) for the synthesis of biobased polycarbonates (PC). In the presented strategy, preparation of the CM-based PC was coupled with chemical recycling of the fossil-based BPA polycarbonate (BPA-PC) conducting a two-steps trans-polymerization that replaces BPA monomer with CM or its tetrahydrogenated colorless product (THCM). In the first step of synthetic strategy, depolymerization of commercial BPA-PC was carried out with phenol as nucleophile, according to our previous procedure based on zinc derivatives and ionic liquids as catalysts, thus producing quantitatively diphenyl carbonate (DPC) e BPA. In the second step, DPC underwent a melt transesterification with CM or THCM monomers affording the corresponding bio-based polycarbonates, CM-PC and THCM-PC, respectively. THCM was prepared by reducing natural bis-phenol with cyclohexene as a hydrogen donor and characterized by 1H-NMR and MS techniques. Polymerization reactions were monitored by infrared spectroscopy and average molecular weights and dispersity of the two biobased polymers THCM-PC and CM-PC were determined by means of gel permeation chromatography (GPC). Optical properties of the prepared polymers were also measured
Modulation of micrornome by human cytomegalovirus and human herpesvirus 6 infection in human dermal fibroblasts: Possible significance in the induction of fibrosis in systemic sclerosis
Human cytomegalovirus (HCMV) and Human herpesvirus 6 (HHVâ6) have been report-edly suggested as triggers of the onset and/or progression of systemic sclerosis (SSc), a severe autoimmune disorder characterized by multiâorgan fibrosis. The etiology and pathogenesis of SSc are still largely unknown but virological and immunological observations support a role for these beta-herpesviruses, and we recently observed a direct impact of HCMV and HHVâ6 infection on the expression of cell factors associated with fibrosis at the cell level. Since miRNA expression has been found profoundly deregulated at the tissue level, here we aimed to investigate the impact on cell microRNome (miRNome) of HCMV and HHVâ6 infection in in vitro infected primary human dermal fibroblasts, which represent one of the main SSc target cells. The analysis, performed by Taq-man arrays detecting and quantifying 754 microRNAs (miRNAs), showed that both herpesviruses significantly modulated miRNA expression in infected cells, with evident early and late effects and deep modulation (>10 fold) of >40 miRNAs at each time post infection, including those previously recognized for their key function in fibrosis. The correlation between these in vitro results with in vivo observations is strongly suggestive of a role of HCMV and/or HHVâ6 in the multistep patho-genesis of fibrosis in SSc and in the induction of fibrosisâsignaling pathways finally leading to tissue fibrosis. The identification of specific miRNAs may open the way to their use as biomarkers for SSc diagnosis, assessment of disease progression and possible antifibrotic therapies
- âŠ