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Cement production is currently the largest single industrial emitter of CO2, accounting for â¼8% (2.8 Gtons/y) of global CO2 emissions. Deep decarbonization of cement manufacturing will require remediation of both the CO2 emissions due to the decomposition of CaCO3 to CaO and that due to combustion of fossil fuels (primarily coal) in calcining (â¼900 °C) and sintering (â¼1,450 °C). Here, we demonstrate an electrochemical process that uses neutral water electrolysis to produce a pH gradient in which CaCO3 is decarbonated at low pH and Ca(OH)2 is precipitated at high pH, concurrently producing a high-purity O2/CO2 gas mixture (1:2 molar ratio at stoichiometric operation) at the anode and H2 at the cathode. We show that the solid Ca(OH)2 product readily decomposes and reacts with SiO2 to form alite, the majority cementitious phase in Portland cement. Electrochemical calcination produces concentrated gas streams from which CO2 may be readily separated and sequestered, H2 and/or O2 may be used to generate electric power via fuel cells or combustors, O2 may be used as a component of oxyfuel in the cement kiln to improve efficiency and lower CO2 emissions, or the output gases may be used for other value-added processes such as liquid fuel production. Analysis shows that if the hydrogen produced by the reactor were combusted to heat the high-temperature kiln, the electrochemical cement process could be powered solely by renewable electricity.
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BACKGROUND: Ivermectin is an antiparasitic drug being investigated in clinical trials for the prevention of COVID-19. However, there are concerns about the quality of some of these trials. OBJECTIVES: To conduct a meta-analysis with randomized controlled trials of ivermectin for the prevention of COVID-19, while controlling for the quality of data. The primary outcome was RT-PCR-confirmed COVID-19 infection. The secondary outcome was rate of symptomatic COVID-19 infection. METHODS: We conducted a subgroup analysis based on the quality of randomized controlled trials evaluating ivermectin for the prevention of COVID-19. Quality was assessed using the Cochrane risk of bias measures (RoB 2) and additional checks on raw data, where possible. RESULTS: Four studies were included in the meta-analysis. One was rated as being potentially fraudulent, two as having a high risk of bias and one as having some concerns for bias. Ivermectin did not have a significant effect on preventing RT-PCR-confirmed COVID-19 infection. Ivermectin had a significant effect on preventing symptomatic COVID-19 infection in one trial with some concerns of bias, but this result was based on post hoc analysis of a multi-arm study. CONCLUSIONS: In this meta-analysis, the use of ivermectin was not associated with the prevention of RT-PCR-confirmed or symptomatic COVID-19. The currently available randomized trials evaluating ivermectin for the prevention of COVID-19 are insufficient and of poor quality.
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Tratamento Farmacológico da COVID-19 , Antiparasitários , Fraude , Humanos , Ivermectina/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
BACKGROUND: The COVER trial evaluated whether nitazoxanide or sofosbuvir/daclatasvir could lower the risk of SARS-CoV-2 infection. Nitazoxanide was selected given its favourable pharmacokinetics and in vitro antiviral effects against SARS-CoV-2. Sofosbuvir/daclatasvir had shown favourable results in early clinical trials. METHODS: In this clinical trial in Johannesburg, South Africa, healthcare workers and others at high risk of infection were randomized to 24â weeks of either nitazoxanide or sofosbuvir/daclatasvir as prevention, or standard prevention advice only. Participants were evaluated every 4â weeks for COVID-19 symptoms and had antibody and PCR testing. The primary endpoint was positive SARS-CoV-2 PCR and/or serology ≥7â days after randomization, regardless of symptoms. A Poisson regression model was used to estimate the incidence rate ratios of confirmed SARS-CoV-2 between each experimental arm and control. RESULTS: Between December 2020 and January 2022, 828 participants were enrolled. COVID-19 infections were confirmed in 100 participants on nitazoxanide (2234 per 1000 person-years; 95% CI 1837-2718), 87 on sofosbuvir/daclatasvir (2125 per 1000 person-years; 95% CI 1722-2622) and 111 in the control arm (1849 per 1000 person-years; 95% CI 1535-2227). There were no significant differences in the primary endpoint between the treatment arms, and the results met the criteria for futility. In the safety analysis, the frequency of grade 3 or 4 adverse events was low and similar across arms. CONCLUSIONS: In this randomized trial, nitazoxanide and sofosbuvir/daclatasvir had no significant preventative effect on infection with SARS-CoV-2 among healthcare workers and others at high risk of infection.
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COVID-19 , Antivirais/uso terapêutico , COVID-19/prevenção & controle , Carbamatos , Humanos , Imidazóis , Nitrocompostos , Pirrolidinas , SARS-CoV-2 , Sofosbuvir/uso terapêutico , África do Sul , Tiazóis , Resultado do Tratamento , Valina/análogos & derivadosRESUMO
A 19-year-old appendix mare was presented with severe, acute right forelimb lameness and a history of significant hoof wall defect. The defect began as progressive toe separation affecting the dorsal hoof wall, which was eventually resected by a farrier. Placement of bar shoes by a farrier to stabilize the hoof was ineffective. Radiographs showed hoof wall separation, palmar rotation, and displacement of the coffin bone, consistent with failure of the laminar structures. Treatment included phenylbutazone, radiographic-guided therapeutic farriery consisting of derotation with a wedge shoe, and restriction to a small, dry paddock.
Maladie de la ligne blanche chez une jument Appendix âgée de 19 ans. Une jument Appendix âgée de 19 ans fut présentée avec une boiterie aiguë sévère de la patte avant droite et une histoire de défaut significatif de la muraille du sabot. Le défaut débuta comme une séparation progressive de l'orteil affectant la paroi dorsale du sabot, qui fut éventuellement enlevée par un forgeron. La mise en place de fers fermés par un forgeron pour stabiliser le sabot s'avéra inefficace. Des radiographies ont montré une séparation de la muraille du sabot, une rotation palmaire et un déplacement de l'os du pied, compatibles avec une défaillance des structures laminaires. Le traitement a inclus de la phénylbutazone, des ferrages thérapeutiques guidés par radiographie consistant en une dérotation avec un fer angulaire et restriction à un petit paddock sec.(Traduit par Dr Serge Messier).
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Apêndice , Doenças do Pé , Casco e Garras , Doenças dos Cavalos , Animais , Fenômenos Biomecânicos , Feminino , Doenças do Pé/veterinária , Membro Anterior , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/cirurgia , Cavalos , SapatosRESUMO
BACKGROUND: Currently, only dexamethasone, tocilizumab, and sarilumab have conclusively been shown to reduce mortality of coronavirus disease 2019 (COVID-19). Safe and effective treatments will need to be both affordable and widely available globally to be used alongside vaccination programs. This analysis will estimate and compare potential generic minimum costs of a selection of approved COVID-19 drug candidates with available international list prices. METHODS: We searched for repurposed drugs that have been approved by at least one of the World Health Organization, US Food and Drug Administration, or the United Kingdom National Institute of Health and Care Excellence organizations or at least given emergency use authorization or recommended for off-label prescription. Drug prices were searched for dexamethasone, budesonide, baricitinib, tocilizumab, casirivimab, and imdevimab, and sarilumab, using active pharmaceutical ingredients (APIs) data extracted from global shipping records. This was compared with national pricing data from a range of low-, medium-, and high-income countries. Annual API export volumes from India were used to estimate the current availability of each drug. RESULTS: Repurposed therapies can be generically manufactured for some treatments at very low per-course costs, ranging from US $2.58 for intravenous (IV) dexamethasone (or US $0.19 orally) and US $4.34 for inhaled budesonide. No export price data were available for baricitinib, tocilizumab, casirivimab, and imdevimab, or sarilumab, but courses of these treatments have higher prices, ranging from US $6.67 for baricitinib to US $875.5 for sarilumab. When comparing international list prices, we found wide variations between countries. CONCLUSIONS: Successful management of COVID-19 will require equitable access to treatment for all populations, not just those able to pay high prices. Dexamethasone and budesonide are widely available and affordable, whereas monoclonal antibodies and IV treatment courses are more expensive.
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Pfizer and the Medicines Patent Pool (MPP) have reached a voluntary licensing agreement for Paxlovid (nirmatrelvir+ritonavir), a novel antiviral for coronavirus disease 2019 (COVID-19) taken orally in the first 5 days from symptom onset. The Pfizer-MPP deal enables 95 low- and middle-income countries (L/MICs) to access affordable biosimilars. Generics are delayed awaiting bioequivalence testing and may be ineffective in L/MICs with reduced testing capacity, which comprise only 10% of global diagnoses. Thirty-nine percent of diagnoses originate in MICs forced to pay high prices due to exclusion from the Pfizer-MPP deal. The cost-effectiveness of Paxlovid could be limited compared with the creation of sustainable vaccine infrastructure in these nations, delaying socioeconomic pandemic recovery. Furthermore, Paxlovid may not be cost-effective in vaccinated populations, and concerns remain over ritonavir drug interactions with COVID-19 comorbidity medications. We call for expanded coverage by the Paxlovid-MPP deal and greater access to testing.
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[This retracts the article DOI: 10.1093/ofid/ofab358.]
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In high-risk individuals in Johannesburg, during the Delta coronavirus disease 2019 wave, 22% (125/561) were positive, with 33% symptomatic (2 hospitalizations; 1 death). During Omicron, 56% (232/411) were infected, with 24% symptomatic (no hospitalizations or deaths). The remarkable speed of infection of Omicron over Delta poses challenges to conventional severe acute respiratory syndrome coronavirus 2 control measures.
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Background: Ivermectin which was widely considered as a potential treatment for COVID-19, showed uncertain clinical benefit in many clinical trials. Performing large-scale clinical trials to evaluate the effectiveness of this drug in the midst of the pandemic, while difficult, has been urgently needed. Methods: We performed two large multicenter randomized, double-blind, placebo-controlled clinical trials evaluating the effectiveness of ivermectin in treating inpatients and outpatients with COVID-19 infection. The intervention group received ivermectin, 0.4mg/kg of body weight per day for 3 days. In the control group, placebo tablets were used for 3 days. Results: Data for 609 inpatients and 549 outpatients were analyzed. In hospitalized patients, complete recovery was significantly higher in the ivermectin group (37%) compared to placebo group (28%; RR, 1.32 [95% CI, 1.04-1.66]; p-value = 0.02). On the other hand, the length of hospital stay was significantly longer in the ivermectin group with a mean of 7.98 ± 4.4 days compared to the placebo receiving group with a mean of 7.16 ± 3.2 days (RR, 0.80 [95% CI, 0.15-1.45]; p-value = 0.02). In outpatients, the mean duration of fever was significantly shorter (2.02 ± 0.11 days) in the ivermectin group versus (2.41 ± 0.13 days) placebo group with p value = 0.020. On the day seventh of treatment, fever (p-value = 0.040), cough (p-value = 0.019), and weakness (p-value = 0.002) were significantly higher in the placebo group compared to the ivermectin group. Among all outpatients, 7% in ivermectin group and 5% in placebo group needed to be hospitalized (RR, 1.36 [95% CI, 0.65-2.84]; p-value = 0.41). Also, the result of RT-PCR on day five after treatment was negative for 26% of patients in the ivermectin group versus 32% in the placebo group (RR, 0.81 [95% CI, 0.60-1.09]; p-value = 0.16). Conclusion: Our data showed, ivermectin, compared with placebo, did not have a significant potential effect on clinical improvement, reduced admission in ICU, need for invasive ventilation, and death in hospitalized patients; likewise, no evidence was found to support the prescription of ivermectin on recovery, reduced hospitalization and increased negative RT-PCR assay for SARS-CoV-2 5 days after treatment in outpatients. Our findings do not support the use of ivermectin to treat mild to severe forms of COVID-19. Clinical Trial Registration: www.irct.ir IRCT20111224008507N5 and IRCT20111224008507N4.
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Ivermectin is an antiparasitic drug being investigated for repurposing against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Ivermectin showed in vitro activity against SARS-COV-2, but only at high concentrations. This meta-analysis investigated ivermectin in 23 randomized clinical trials (3349 patients) identified through systematic searches of PUBMED, EMBASE, MedRxiv, and trial registries. The primary meta-analysis was carried out by excluding studies at a high risk of bias. Ivermectin did not show a statistically significant effect on survival (risk ratio [RR], 0.90; 95% CI, 0.57 to 1.42; P = .66) or hospitalizations (RR, 0.63; 95% CI, 0.36 to 1.11; P = .11). Ivermectin displayed a borderline significant effect on duration of hospitalization in comparison with standard of care (mean difference, -1.14 days; 95% CI, -2.27 to -0.00; P = .05). There was no significant effect of ivermectin on time to clinical recovery (mean difference, -0.57 days; 95% CI, -1.31 to 0.17; P = .13) or binary clinical recovery (RR, 1.19; 95% CI, 0.94 to 1.50; P = .15). Currently, the World Health Organization recommends the use of ivermectin only inside clinical trials. A network of large clinical trials is in progress to validate the results seen to date.