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This work aimed to evaluate the catalytic activity of the catalysts niobium phosphate (PNb), niobium acid (HNb) and the 1:1 mechanical mixture of both catalysts (HPNb) based on the results obtained for the yield of glucose, xylose, 5-hydroxymethylfurfural (HMF) and furfural (FF) using holocellulose, solid material with a high cellulose and hemicellulose content, as raw material. The variables studied were temperature and time between 150 and 200 °C and 0 and 360 min. The reaction mixture consisted of an aqueous solution containing 6% (m/m) holocellulose and a holocellulose/catalyst ratio of 3:1. The highest yield obtained for HMF was 44.8 g/kg(holocellulose) at 200 °C with a reaction time of 60 min. For FF, a 69.8 g/kg(holocellulose) yield was obtained at 200 °C and 90 min. The yields obtained with HPNb exhibited intermediate results compared to PNb and HMF catalysts, with no significant differences justifying using a mixture of both catalysts.

This work aimed to evaluate the catalytic activity of the catalysts niobium phosphate (PNb), niobium acid (HNb) and the 1:1 mechanical mixture of both catalysts (HPNb) based on the results obtained for the yield of glucose, xylose, 5-hydroxymethylfurfural (HMF) and furfural (FF) using holocellulose, solid material with a high cellulose and hemicellulose content, as raw material. The variables studied were temperature and time between 150 and 200 °C and 0 and 360 min. The reaction mixture consisted of an aqueous solution containing 6% (m/m) holocellulose and a holocellulose/catalyst ratio of 3:1. The highest yield obtained for HMF was 44.8 g/kg(holocellulose) at 200 °C with a reaction time of 60 min. For FF, a 69.8 g/kg(holocellulose) yield was obtained at 200 °C and 90 min. The yields obtained with HPNb exhibited intermediate results compared to PNb and HMF catalysts, with no significant differences justifying using a mixture of both catalysts. [ABSTRACT FROM AUTHOR]

Aggregation and accumulation of amyloid-β peptide (Aβ) are a critical trigger for the onset of Alzheimer's disease (AD). While the plaques are the most outstanding Aβ pathological feature, much of the recent research emphasis has been on soluble Aβ species because of their diffusible, proinflammatory, and toxic properties. The focus on soluble aggregated Aβ species has also increased the interest in antibodies that are selective for different Aβ conformations. In the current study, we developed and characterized a new class of monoclonal antibodies (referred to as mAbSL) that are selective for Aβ protofibrils. Cloning and sequencing of the heavy and light chain variable regions for multiple antibodies identified sequence characteristics that may impart the conformational selectivity by the antibodies. Transfection of FreeStyle 293F cells with the plasmids permitted in-house expression and purification of mAbSL antibodies along with non-conformation-selective Aβ monoclonal antibodies (Aβ mAbs). Several of the purified mAbSL antibodies demonstrated significant affinity and selectivity for Aβ42 protofibrils compared with Aβ42 monomers and Aβ42 fibrils. Competition ELISA assays assessing the best overall antibody, mAbSL 113, yielded affinity constants of 7 nM for the antibody-Aβ42 protofibril interaction, while the affinity for either Aβ42 monomers or Aβ42 fibrils was roughly 80 times higher. mAbSL 113 significantly inhibited Aβ42 monomer aggregation by a unique mechanism compared with the inhibition displayed by Aβ mAb 513. Aβ42 protofibril dynamics were also markedly altered in the presence of mAbSL 113, whereby insoluble complex formation and protofibril deposition were stimulated by the antibody at low substoichiometric molar ratios. As the field contemplates the therapeutic effectiveness of Aβ conformation-selective antibodies, the findings presented here demonstrate new information on a monoclonal antibody that selectively targets Aβ protofibrils and impacts Aβ dynamics., (© 2023 International Society for Neurochemistry.)

Effective coral restoration must include comprehensive investigations of the targeted coral community that consider all aspects of the coral holobiont-the coral host, symbiotic algae, and microbiome. For example, the richness and composition of microorganisms associated with corals may be indicative of the corals' health status and thus help guide restoration activities. Potential differences in microbiomes of restoration corals due to differences in host genetics, environmental condition, or geographic location, may then influence outplant success. The objective of the present study was to characterize and compare the microbiomes of apparently healthy Acropora cervicornis genotypes that were originally collected from environmentally distinct regions of Florida's Coral Reef and sampled after residing within Mote Marine Laboratory's in situ nursery near Looe Key, FL (USA) for multiple years. By using 16S rRNA high-throughput sequencing, we described the microbial communities of 74 A. cervicornis genotypes originating from the Lower Florida Keys ( n  = 40 genotypes), the Middle Florida Keys ( n  = 15 genotypes), and the Upper Florida Keys ( n  = 19 genotypes). Our findings demonstrated that the bacterial communities of A. cervicornis originating from the Lower Keys were significantly different from the bacterial communities of those originating from the Upper and Middle Keys even after these corals were held within the same common garden nursery for an average of 3.4 years. However, the bacterial communities of corals originating in the Upper Keys were not significantly different from those in the Middle Keys. The majority of the genotypes, regardless of collection region, were dominated by Alphaproteobacteria, namely an obligate intracellular parasite of the genus Ca. Aquarickettsia . Genotypes from the Upper and Middle Keys also had high relative abundances of Spirochaeta bacteria. Several genotypes originating from both the Lower and Upper Keys had lower abundances of Aquarickettsia , resulting in significantly higher species richness and diversity. Low abundance of Aquarickettsia has been previously identified as a signature of disease resistance. While the low- Aquarickettsia corals from both the Upper and Lower Keys had high abundances of an unclassified Proteobacteria, the genotypes in the Upper Keys were also dominated by Spirochaeta . The results of this study suggest that the abundance of Aquarickettsia and Spirochaeta may play an important role in distinguishing bacterial communities among A. cervicornis populations and compositional differences of these bacterial communities may be driven by regional processes that are influenced by both the environmental history and genetic relatedness of the host. Additionally, the high microbial diversity of low- Aquarickettsia genotypes may provide resilience to their hosts, and these genotypes may be a potential resource for restoration practices and management., Competing Interests: The authors declare there are no competing interests., (©2022 Williams et al.)