19 research outputs found

    Copper-catalysed cross-coupling of alkyl Grignard reagents and propargylic ammonium salts: Stereospecific synthesis of allenes

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    Herein we describe a robust and practical method to prepare enantiomerically enriched trisubstituted allenes using alkyl Grignard reagents and bench stable propargylic ammonium salts. Excellent yields as well as regio- and stereoselectivities are observed. Our conditions provide a solution to the allene racemization, which has been a long-standing problem when using Grignard reagents

    A communal catalogue reveals Earth's multiscale microbial diversity

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    Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe

    A communal catalogue reveals Earth’s multiscale microbial diversity

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    Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

    A first update on mapping the human genetic architecture of COVID-19

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    Cognitive Function with PCSK9 Inhibitors: A 24-Month Follow-Up Observational Prospective Study in the Real World—MEMOGAL Study

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    Introduction The cognitive safety of monoclonal antibody proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) has been established in clinical trials, but not yet in real-world observational studies. We assessed the cognitive function in patients initiating PCSK9i, and differences in cognitive function domains, to analyze subgroups by the low-density lipoprotein cholesterol (LDL-C) achieved, and differences between alirocumab and evolocumab. Methods This has a multicenter, quasi-experimental design carried out in 12 Spanish hospitals from May 2020 to February 2023. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Results Among 158 patients followed for a median of 99 weeks, 52% were taking evolocumab and 48% alirocumab; the mean change from baseline in MoCA score at follow-up was + 0.28 [95% CI (− 0.17 to 0.73; p = 0.216)]. There were no significant differences in the secondary endpoints—the visuospatial/executive domain + 0.04 (p = 0.651), naming domain − 0.01 (p = 0.671), attention/memory domain + 0.01 (p = 0.945); language domain − 0.10 (p = 0.145), abstraction domain + 0.03 (p = 0.624), and orientation domain − 0.05 (p = 0.224)—but for delayed recall memory the mean change was statistically significant (improvement) + 0.44 (p = 0.001). Neither were there any differences in the three stratified subgroups according to lowest attained LDL-C level—0–54 mg/dL, 55–69 mg/dL and ≥ 70 mg/dL; p = 0.454—or between alirocumab and evolocumab arms. Conclusion We did not find effect of monoclonal antibody PCSK9i on neurocognitive function over 24 months of treatment, either in global MoCA score or different cognitive domains. An improvement in delayed recall memory was shown. The study showed no differences in the cognitive function between the prespecified subgroups, even among patients who achieved very low levels of LDL-C. There were no differences between alirocumab and evolocumab. Registration ClinicalTtrials.gov Identifier number NCT04319081Open Access funding provided thanks to the CRUE-CSIC agreement with Springer NatureS
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