Catálogo de publicaciones - revistas

<jats:p>Two-dimensional transition-metal carbides and nitrides (MXenes) are a large family of materials actively studied for various applications, especially in the field of energy storage. MXenes are commonly synthesized by etching the layered ternary compounds, called MAX phases. We demonstrate a direct synthetic route for scalable and atom-economic synthesis of MXenes, including compounds that have not been synthesized from MAX phases, by the reactions of metals and metal halides with graphite, methane, or nitrogen. The direct synthesis enables chemical vapor deposition growth of MXene carpets and complex spherulite-like morphologies that form through buckling and release of MXene carpet to expose fresh surface for further reaction. The directly synthesized MXenes showed excellent energy storage capacity for lithium-ion intercalation.</jats:p>

<jats:p>Among the diverse areas of 3D printing, high-quality silicone printing is one of the least available and most restrictive. However, silicone-based components are integral to numerous advanced technologies and everyday consumer products. We developed a silicone 3D printing technique that produces precise, accurate, strong, and functional structures made from several commercially available silicone formulations. To achieve this level of performance, we developed a support material made from a silicone oil emulsion. This material exhibits negligible interfacial tension against silicone-based inks, eliminating the disruptive forces that often drive printed silicone features to deform and break apart. The versatility of this approach enables the use of established silicone formulations in fabricating complex structures and features as small as 8 micrometers in diameter.</jats:p>

<jats:p> The Chilean soapbark tree ( <jats:italic>Quillaja saponaria</jats:italic> ) produces soap-like molecules called QS saponins that are important vaccine adjuvants. These highly valuable compounds are sourced by extraction from the bark, and their biosynthetic pathway is unknown. Here, we sequenced the <jats:italic>Q. saponaria</jats:italic> genome. Through genome mining and combinatorial expression in tobacco, we identified 16 pathway enzymes that together enable the production of advanced QS pathway intermediates that represent a bridgehead for adjuvant bioengineering. We further identified the enzymes needed to make QS-7, a saponin with excellent therapeutic properties and low toxicity that is present in low abundance in <jats:italic>Q. saponaria</jats:italic> bark extract. Our results enable the production of <jats:italic>Q. saponaria</jats:italic> vaccine adjuvants in tobacco and open the way for new routes to access and engineer natural and new-to-nature immunostimulants. </jats:p>

<jats:p> Spinal muscular atrophy (SMA), the leading genetic cause of infant mortality, arises from SMN protein insufficiency following <jats:italic>SMN1</jats:italic> loss. Approved therapies circumvent endogenous SMN regulation and require repeated dosing or may wane. We describe genome editing of <jats:italic>SMN2</jats:italic> , an insufficient copy of <jats:italic>SMN1</jats:italic> harboring a C6&gt;T mutation, to permanently restore SMN protein levels and rescue SMA phenotypes. We used nucleases or base editors to modify five <jats:italic>SMN2</jats:italic> regulatory regions. Base editing converted <jats:italic>SMN2</jats:italic> T6&gt;C, restoring SMN protein levels to wild-type. AAV9-mediated base editor delivery in Δ7SMA mice yielded 87% average T6&gt;C conversion, improved motor function, and extended average lifespan, which was enhanced by one-time base editor+nusinersen co-administration (111 versus 17 days untreated). These findings demonstrate the potential of a one-time base editing treatment for SMA. </jats:p>

<jats:p>Despite the vast diversity of the antibody repertoire, infected individuals often mount antibody responses to precisely the same epitopes within antigens. The immunological mechanisms underpinning this phenomenon remain unknown. By mapping 376 immunodominant “public epitopes” at high resolution and characterizing several of their cognate antibodies, we concluded that germline-encoded sequences in antibodies drive recurrent recognition. Systematic analysis of antibody-antigen structures uncovered 18 human and 21 partially overlapping mouse germline-encoded amino acid–binding (GRAB) motifs within heavy and light V gene segments that in case studies proved critical for public epitope recognition. GRAB motifs represent a fundamental component of the immune system’s architecture that promotes recognition of pathogens and leads to species-specific public antibody responses that can exert selective pressure on pathogens.</jats:p>

<jats:p>When the first cases of human infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were reported from Wuhan, China, in December 2019, there was quick agreement across scientific and health communities that understanding the facts about its emergence would help prevent future outbreaks. Never could I have imagined the degree of politicization that would cloud this quest. Over the past 39 months, while reported deaths from COVID-19 increased to nearly 7 million worldwide, science on the virus’s origins has gotten smaller while the politics surrounding this question has grown ever bigger. Last month, the World Health Organization (WHO) learned that scientists in China possessed data on viral samples from Wuhan that had been gathered in January 2020, which should have been shared immediately—not 3 years later—with the global research community. The lack of data disclosure is simply inexcusable. The longer it takes to understand the origins of the pandemic, the harder it becomes to answer the question, and the more unsafe the world becomes.</jats:p>

<jats:p>Researchers sound alarm over damage caused by popular meteorite-hunting technique</jats:p>