6 research outputs found

    Total Synthesis of Mansouramycin A

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    In 2009 bioactive compounds from marine Streptomyces species was isolated which resulted in deriving four isoquinoline-quinone alkaloids known as Mansouramycins A-D. There have been reports that there are 36 non-small cancer cells against cytotoxicity in Mansouramycins A-C in lung cancer, breast cancer, melanoma, and prostate cancer cells. Reports that have conducted total syntheses were all specific to a single compound only Mansouramycin A and D. However, in precedent methods, to obtain the derivatives with different substituents are limited when the substituents are on the fused-pyridine ring. Thus, a develop a systematic synthetic methods of isoquinoline-quinones, which are to be able to obtain the natural Mansouramycins and their derivative by the usage of different amino acids via synthesis the aminoacetals

    Removal of Cu2+ and Ni2+ from Aqueous Solution using SnO2 Nanomaterial effect of: pH, Time, Temperature, interfering cations

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    Tin oxide, SnO2, nanomaterial was synthesized and tested for the removal of Cu2+ and Ni2+ ions from aqueous solutions. Various parameters for the binding were investigated in batch studied, which included pH, time, temperature, and interferences. In addition, isotherm studied were performed to determine the maximum binding capacity for both Cu2+ and Ni2+ ions. The optimal binding pH determined from the effects of pH were to be at pH 5 for both the Cu2+ and Ni2+ ions. The isotherm studies were performed at temperatures of 4°C, 25 °C, and 45 °C for both the Cu2+ and Ni2+ ions and were found to follow the Langmuir isotherm model. The binding capacities for the Cu2+ ions were 2.63 mg/g, 2.95 mg/g and 3.27 mg/g at the aforementioned temperatures, respectively. Whereas the binding capacities for Ni2+ were 0.79 mg/g, 1.07 mg/g, and 1.46 mg/g at the respective temperatures. The determined thermodynamic parameters for the binding showed that the binding processes for the reactions were endothermic, as the ΔG was observed to decrease with decreasing temperatures. As well the ΔH was 28.73 kJ/mol for Cu2+ (III) and 13.37 kJ/mol for Ni2+. The ΔS was observed to be 92.65 J/mol for Cu2+ and 54.53 J/mol for Ni2+. The free energy of adsorption for the Cu2+ was determined to be 13.99 kJ/mol and the activation energy for the binding of Ni2+ was determined to be 8.09 KJ/mol. The activation energy data indicate that the reaction was occurring through chemisorptio

    Broadly neutralizing antibodies overcome SARS-CoV-2 Omicron antigenic shift

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    The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593 and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.Fil: Cameroni, Elisabetta. Humabs Biomed; SuizaFil: Bowen, John E.. University of Washington; Estados UnidosFil: Rosen, Laura E.. Vir Biotechnology; Estados UnidosFil: Saliba, Christian. Humabs Biomed; SuizaFil: Zepeda, Samantha K.. University of Washington; Estados UnidosFil: Culap, Katja. Humabs Biomed; SuizaFil: Pinto, Dora. Humabs Biomed; SuizaFil: VanBlargan, Laura A.. Washington University in St. Louis; Estados UnidosFil: De Marco, Anna. Humabs Biomed; SuizaFil: di Iulio, Julia. Vir Biotechnology; Estados UnidosFil: Zatta, Fabrizia. Humabs Biomed; SuizaFil: Kaiser, Hannah. Vir Biotechnology; Estados UnidosFil: Noack, Julia. Vir Biotechnology; Estados UnidosFil: Farhat, Nisar. Vir Biotechnology; Estados UnidosFil: Czudnochowski, Nadine. Vir Biotechnology; Estados UnidosFil: Havenar Daughton, Colin. Vir Biotechnology; Estados UnidosFil: Sprouse, Kaitlin R.. University of Washington; Estados UnidosFil: Dillen, Josh R.. Vir Biotechnology; Estados UnidosFil: Powell, Abigail E.. Vir Biotechnology; Estados UnidosFil: Chen, Alex. Vir Biotechnology; Estados UnidosFil: Maher, Cyrus. Vir Biotechnology; Estados UnidosFil: Yin, Li. Vir Biotechnology; Estados UnidosFil: Sun, David. Vir Biotechnology; Estados UnidosFil: Soriaga, Leah. Vir Biotechnology; Estados UnidosFil: Bassi, Jessica. Humabs Biomed; SuizaFil: Silacci Fregni, Chiara. Humabs Biomed; SuizaFil: Gustafsson, Claes. ATUM; Estados UnidosFil: Franko, Nicholas M.. University of Washington; Estados UnidosFil: Logue, Jenni. University of Washington; Estados UnidosFil: Geffner, Jorge Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentin

    Broadly neutralizing antibodies overcome SARS-CoV-2 Omicron antigenic shift

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    The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593 and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers
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