A recombinant single-chain antibody fragment that neutralizes toxin II from the venom of the scorpion Androctonus australis hector

AbstractMonoclonal antibody 4C1 specifically binds to and neutralizes the most potent neurotoxin (AahII) of the scorpion Androctonus australis. The cDNAs encoding the variable regions of this antibody were isolated by PCR-mediated cloning. A single-chain Fv gene was engineered and expressed in Escherichia coli. The recombinant protein had neutralizing activity similar to that of the intact antibody in vitro and in vivo. We have thus neutralized the pharmacological and biological properties of a scorpion neurotoxin with a single-chain Fv, which opens new perspectives for the treatment of envenomizations

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Stable trimerization of recombinant rabies virus glycoprotein ectodomain is required for interaction with the p75(NTR) receptor

International audienceNative rabies virus glycoprotein (RVGvir) is a trimeric, membrane-anchored protein that has been shown to interact with the p75(NTR) neurotrophin receptor. In order to determine if the RVG trimeric oligomerization state is required for its binding with p75(NTR), different soluble recombinant molecules containing the entire RVG ectodomain (RVGect) were expressed alone or fused at its C terminus to the trimerization domain of the bacteriophage T4 fibritin, termed 'foldon'. The oligomerization status of recombinant RVG was investigated using sedimentation in sucrose gradient and p75(NTR) binding assays. It was found that, in the absence of the fibritin foldon, recombinant RVGect forms unstable trimers that dissociate into monomers in a concentration-dependent manner. C-terminal fusion with the foldon induces stable RVG trimerization, which is concentration-independent. Furthermore, the fibritin foldon maintains the native antigenic structure of the carboxy part of RVGect. Cell binding experiments showed that RVG trimerization is required for efficient interaction with p75(NTR). However, the exact mode of trimerization appears unimportant, as trimeric recombinant RVGect (fused to the fibritin foldon) and RVGvir both recognize p75(NTR) with similar nanomolar affinities, as shown by surface plasmon resonance experiments. Altogether, these results show that the C-terminal fusion of the RVG ectodomain with the fibritin foldon is a powerful way to obtain a recombinant trimeric native-like structure of the p75(NTR) binding domain of RVG

Polyaniline-Grafted RuO2-TiO2 Heterostructure for the Catalysed Degradation of Methyl Orange in Darkness

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Mixed oxide-polyaniline composite-coated woven cotton fabrics for the visible light catalyzed degradation of hazardous organic pollutants

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Diazonium-modified TiO2/polyaniline core/shell nanoparticles. Structural characterization, interfacial aspects and photocatalytic performances

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Identification of Cryptosporidium Species Infecting Humans in Tunisia

International audiencePrevalence and species distribution of Cryptosporidium spp. were determined among 633 immunocompetent children less than five years of age and 75 patients hospitalized for immunodeficiency who lived in northern Tunisia. Microscopy was used for initial screening to detect positive samples and a nested polymerase chain reaction and restriction fragment length polymorphism analysis was used to determine the species. Cryptosporidium spp. was identified in 2.7% of cases (19 stool samples), and there was a significant difference between samples collected from immunocompromised patients and those collected from healthy children (10.7% versus 1.7%). Prevalence was also significantly higher in diarrheal specimens than in formed specimens (6.3% versus 1.6%). Cyptosporidium hominis and C. parvum were responsible for most Cryptosporidium spp. infections (78.9%). Cryptosporidium hominis was more prevalent in children from urban areas than in those from rural areas, and C parvum was found with similar prevalence rates in the two populations. Cryptosporidium meleagridis was identified in four children on farms

Cathodic Activation of Titania-Fly Ash Cenospheres for Efficient Electrochemical Hydrogen Production: A Proposed Solution to Treat Fly Ash Waste

International audienceFly ash (FA) is a waste product generated in huge amounts by coal-fired electric and steam-generating plants. As a result, the use of FA alone or in conjunction with other materials is an intriguing study topic worth exploring. Herein, we used FA waste in conjunction with titanium oxide (TiO2) to create (FA-TiO2) nanocomposites. For the first time, a cathodic polarization pre-treatment regime was applied to such nanocomposites to efficiently produce hydrogen from an alkaline solution. The FA-TiO2 hybrid nanocomposites were prepared by a straightforward solvothermal approach in which the FA raw material was mixed with titanium precursor in dimethyl sulfoxide (DMSO) and refluxed during a given time. The obtained FA-TiO2 hybrid nanocomposites were fully characterized using various tools and displayed a cenosphere-like shape. The synthesized materials were tested as electrocatalysts for the hydrogen evolution reaction (HER) in 0.1 M KOH solution in the dark, employing various electrochemical techniques. The as-prepared (unactivated) FA-TiO2 exhibited a considerable HER electrocatalytic activity, with an onset potential (EHER) value of −144 mV vs. RHE, a Tafel slope (−bc) value of 124 mV dec−1 and an exchange current density (jo) of ~0.07 mA cm−2. The FA-TiO2′s HER catalytic performance was significantly enhanced upon cathodic activation (24 h of chronoamperometry measurements performed at a high cathodic potential of −1.0 V vs. RHE). The cathodically activated FA-TiO2 recorded HER electrochemical kinetic parameters of EHER = −28 mV, −bc = 115 mV dec−1, jo = 0.65 mA cm−2, and an overpotential η10 = 125 mV to yield a current density of 10 mA cm−2. Such parameters were comparable to those measured here for the commercial Pt/C under the same experimental conditions (EHER = −10 mV, −bc = 113 mV dec−1, jo = 0.88 mA cm−2, η10 = 110 mV), as well as to the most active electrocatalysts for H2 generation from aqueous alkaline electrolytes

COVID-19 Vaccine Booster Dose Acceptance: Systematic Review and Meta-Analysis

The World Health Organization (WHO) recommended coronavirus disease 2019 (COVID-19) booster dose vaccination after completing the primary vaccination series for individuals ≥18 years and most-at-risk populations. This study aimed to estimate the pooled proportion of COVID-19 vaccine booster dose uptake and intention to get the booster dose among general populations and healthcare workers (HCWs). We searched PsycINFO, Scopus, EBSCO, MEDLINE Central/PubMed, ProQuest, SciELO, SAGE, Web of Science, Google Scholar, and ScienceDirect according to PRISMA guidelines. From a total of 1079 screened records, 50 studies were extracted. Meta-analysis was conducted using 48 high-quality studies according to the Newcastle-Ottawa Scale quality assessment tool. Using the 48 included studies, the pooled proportion of COVID-19 vaccine booster dose acceptance among 198,831 subjects was 81% (95% confidence interval (CI): 75–85%, I2 = 100%). The actual uptake of the booster dose in eight studies involving 12,995 subjects was 31% (95% CI: 19–46%, I2 = 100%), while the intention to have the booster dose of the vaccine was 79% (95% CI: 72–85%, I2 = 100%). The acceptance of the booster dose of COVID-19 vaccines among HCWs was 66% (95% CI: 58–74%), I2 = 99%). Meta-regression revealed that previous COVID-19 infection was associated with a lower intention to have the booster dose. Conversely, previous COVID-19 infection was associated with a significantly higher level of booster dose actual uptake. The pooled booster dose acceptance in the WHO region of the Americas, which did not include any actual vaccination, was 77% (95% CI: 66–85%, I2 = 100%). The pooled acceptance of the booster dose in the Western Pacific was 89% (95% CI: 84–92%, I2 = 100), followed by the European region: 86% (95% CI: 81–90%, I2 = 99%), the Eastern Mediterranean region: 59% (95% CI: 46–71%, I2 = 99%), and the Southeast Asian region: 52% (95% CI: 43–61%, I2 = 95). Having chronic disease and trust in the vaccine effectiveness were the significant predictors of booster dose COVID-19 vaccine acceptance. The global acceptance rate of COVID-19 booster vaccine is high, but the rates vary by region. To achieve herd immunity for the disease, a high level of vaccination acceptance is required. Intensive vaccination campaigns and programs are still needed around the world to raise public awareness regarding the importance of accepting COVID-19 vaccines needed for proper control of the pandemic