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Spiro-heterocyclic indolenines are privileged scaffolds widely present in numerous indole alkaloids. Here, we develop a novel approach for the one-pot multistep synthesis of different spiro[indole-isoquinolines]. The protocol proposed involves the visible light mediated oxidation of N-aryl tertiary amines using bromochloroform with the generation of a reactive iminium species, which reacts with an isocyanide and an electron-rich aniline in a three-component Ugi-type reaction to give an α-aminoamidine. This compound might undergo an additional visible light-mediated oxidation to furnish a second iminium intermediate, which acts as electrophile in an intramolecular electrophilic aromatic substitution giving the final spiro-indolenine. The scope of the process has been investigated with respect to all three components. Simple operations, mild conditions, and good yields make this strategy a convenient and sustainable way to obtain novel spiro-indolenine derivatives.

Abstract Live-Attenuated Vaccines (LAVs) stimulate robust mucosal and cellular responses and have the potential to protect against Respiratory Syncytial Virus (RSV) and Human Metapneumovirus (HMPV), the main etiologic agents of viral bronchiolitis and pneumonia in children. We inserted the RSV-F gene into an HMPV-based LAV (Metavac®) we previously validated for the protection of mice against HMPV challenge, and rescued a replicative recombinant virus (Metavac®-RSV), exposing both RSV- and HMPV-F proteins at the virion surface and expressing them in reconstructed human airway epithelium models. When administered to BALB/c mice by the intranasal route, bivalent Metavac®-RSV demonstrated its capacity to replicate with reduced lung inflammatory score and to protect against both RSV and lethal HMPV challenges in vaccinated mice while inducing strong IgG and broad RSV and HMPV neutralizing antibody responses. Altogether, our results showed the versatility of the Metavac® platform and suggested that Metavac®-RSV is a promising mucosal bivalent LAV candidate to prevent pneumovirus-induced diseases.

RESUMO O catálogo de fotoidentificação da população de boto-cinza, Sotalia fluviatilis, da Baía de Sepetiba vem sendo formado desde 1994. São apresentados os dados preliminares do período entre abril de 1994 a junho de 1998, os quais indicam haver fidelidade ao habitat e algum grau de associação entre indivíduos. São também apresentados os diversos problemas de campo que levam a baixos índices de aproveitamento de fotos. O catálogo de fotoidentificação vem gerando informações que subsidiarão futuros estudos ecológicos, necessários à proposição de medidas que permitirão a conservação da espécie nesta baía.

Several studies have investigated the antibody response to SARS-CoV-2, focusing particularly on the systemic humoral immune response and the production of immunoglobulin G (IgG) antibodies. IgA antibodies play a crucial role in protecting against respiratory viral infections but have also been associated with the pathophysiology of COVID-19. We performed a prospective study of 169 COVID-19 patients – 50 with critical/severe (ICU), 47 with moderate (Non-ICU), and 72 with asymptomatic COVID-19 – to explore the humoral immune response to SARS-CoV-2 infection. We found that the early systemic IgA response strongly induced in patients with severe disease did not block IgG neutralization functions and activated FcRs more effectively than IgG. However, even if SIgA levels were high, mucosal IgA antibodies could not control the infection effectively in patients with severe disease. Our findings highlight the complexity of the immune response to SARS-CoV-2 exhibiting high systemic levels of IgA with strong neutralizing capacity in severe cases, together with higher levels of IgA-FcR activation than in asymptomatic patients. They also suggest the need for further research to fully understand the role of IgA and its structural alterations in mucosal tissues in cases of severe disease and the impact of these antibodies on disease progression.

An analytical method for the determination of toxicological relevant species of arsenic in urine was developed and validated using hydride generation microwave-induced emission spectrometry (HG-MP-AES). This strategy can be used as an alternative to HG-HPLC-ICP-MS considered as a reference technique for arsenic speciation. This procedure is notably less expensive than other techniques and sample preparation and requires only a few steps. • Hydride generation with MP-AES detection has proven to be an effective technique for measuring arsenic metabolites in urine, which is relevant for occupational monitoring and health risk assessment purposes. • This method offers simplicity and cost-effectiveness, serving as an alternative to classical analytical procedures typically used for arsenic analysis in urine. • The methodology has been successfully applied for the purpose of workers' health surveillance.

Agriculture is the primary food source and fundamental for human survival. However, managing pests and diseases of crops remains a challenge. Moreover, climate change events such as drought, soil depletion, and low nutrient use efficiency are significant barriers to global food security. Nanotechnology has emerged as a possibility for resolving these issues. Nanomaterials have different properties compared to their bulk forms, which allows for a wide range of new applications. An urgent demand is for the combat against pests and pathogens that cause significant losses to different cultivars, and many are still acquiring resistance, which makes this fight a challenge. Many nanomaterials have demonstrated the ability to combat such pathogens, raising their potential application. In this review, we will discuss the use of nanomaterials in combating a wide variety of pathogens and pests that constantly affect different cultivars around the world. The efficiency of the treatments varied depending on the type of nanomaterial as well as characteristics such as size and morphology. Furthermore, the dosage was another determining factor in the outcome, so that there were relevant results with improved plant development and performance. Also, we demonstrated recent advances in controlling virus infections that affect a wide variety of cultivars. We also discuss the potential to combat the most common pests and the possible mechanisms of action of these nanomaterials, which make them capable of affecting a broad spectrum of organisms. Nanomaterials probably act through different pathways, and the resulting pathways would allow the control of these pests and diseases. However, the threshold between toxicity and beneficial effects is still difficult to determine, and the resulting toxicity varied among the different cultivars reviewed. We present the challenges that still exist and perspectives for the use and commercialization of nanoproducts.

Over the years, science and technology have enabled improvement in various sectors of society through the development of products, services, and applications. Despite the tremendous scientific development, it is necessary to understand and pay attention to the environmental, social, and clinical consequences generated by developing a new product and service. Bionanotechnology emerges as a multidisciplinary and transdisciplinary science capable of presenting strategies based on sustainability and biocompatibility with living beings. Therefore, it seeks to solve, with plurality, the emerging problems through manipulating matter at atomic and molecular scales and its application in biological systems. One of the bionanotechnological alternatives that this review will address is the use of nanoparticles synthesized from natural extracts with various applications that can solve emerging problems on the planet, such as the excessive use of agrochemicals, resistant pathogenic microorganisms, the misuse of natural resources and improper disposal of plastics. This review aims to present bionanotechnology as a strategy for sustainable development in emerging problems in health, agriculture, and maintaining biodiversity and population problems.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is initiated by binding of the viral Spike protein to host receptor angiotensin-converting enzyme 2 (ACE2), followed by fusion of viral and host membranes. Although antibodies that block this interaction are in emergency use as early coronavirus disease 2019 (COVID-19) therapies, the precise determinants of neutralization potency remain unknown. We discovered a series of antibodies that potently block ACE2 binding but exhibit divergent neutralization efficacy against the live virus. Strikingly, these neutralizing antibodies can inhibit or enhance Spike-mediated membrane fusion and formation of syncytia, which are associated with chronic tissue damage in individuals with COVID-19. As revealed by cryoelectron microscopy, multiple structures of Spike-antibody complexes have distinct binding modes that not only block ACE2 binding but also alter the Spike protein conformational cycle triggered by ACE2 binding. We show that stabilization of different Spike conformations leads to modulation of Spike-mediated membrane fusion with profound implications for COVID-19 pathology and immunity.