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1.
Proc Natl Acad Sci U S A ; 121(9): e2319436121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38386712

RESUMO

Terrestrial enhanced weathering (EW) of silicate rocks, such as crushed basalt, on farmlands is a promising scalable atmospheric carbon dioxide removal (CDR) strategy that urgently requires performance assessment with commercial farming practices. We report findings from a large-scale replicated EW field trial across a typical maize-soybean rotation on an experimental farm in the heart of the United Sates Corn Belt over 4 y (2016 to 2020). We show an average combined loss of major cations (Ca2+ and Mg2+) from crushed basalt applied each fall over 4 y (50 t ha-1 y-1) gave a conservative time-integrated cumulative CDR potential of 10.5 ± 3.8 t CO2 ha-1. Maize and soybean yields increased significantly (P < 0.05) by 12 to 16% with EW following improved soil fertility, decreased soil acidification, and upregulation of root nutrient transport genes. Yield enhancements with EW were achieved with significantly (P < 0.05) increased key micro- and macronutrient concentrations (including potassium, magnesium, manganese, phosphorus, and zinc), thus improving or maintaining crop nutritional status. We observed no significant increase in the content of trace metals in grains of maize or soybean or soil exchangeable pools relative to controls. Our findings suggest that widespread adoption of EW across farming sectors has the potential to contribute significantly to net-zero greenhouse gas emissions goals while simultaneously improving food and soil security.


Assuntos
Silicatos , Oligoelementos , Zea mays , Agricultura , Solo , Dióxido de Carbono , Glycine max
2.
RNA ; 30(7): 779-794, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38565242

RESUMO

The stem-loop 2 motif (s2m) in SARS-CoV-2 (SCoV-2) is located in the 3'-UTR. Although s2m has been reported to display characteristics of a mobile genomic element that might lead to an evolutionary advantage, its function has remained unknown. The secondary structure of the original SCoV-2 RNA sequence (Wuhan-Hu-1) was determined by NMR in late 2020, delineating the base-pairing pattern and revealing substantial differences in secondary structure compared to SARS-CoV-1 (SCoV-1). The existence of a single G29742-A29756 mismatch in the upper stem of s2m leads to its destabilization and impedes a complete NMR analysis. With Delta, a variant of concern has evolved with one mutation compared to the original sequence that replaces G29742 by U29742. We show here that this mutation results in a more defined structure at ambient temperature accompanied by a rise in melting temperature. Consequently, we were able to identify >90% of the relevant NMR resonances using a combination of selective RNA labeling and filtered 2D NOESY as well as 4D NMR experiments. We present a comprehensive NMR analysis of the secondary structure, (sub)nanosecond dynamics, and ribose conformation of s2m Delta based on heteronuclear 13C NOE and T 1 measurements and ribose carbon chemical shift-derived canonical coordinates. We further show that the G29742U mutation in Delta has no influence on the druggability of s2m compared to the Wuhan-Hu-1 sequence. With the assignment at hand, we identify the flexible regions of s2m as the primary site for small molecule binding.


Assuntos
Conformação de Ácido Nucleico , RNA Viral , SARS-CoV-2 , SARS-CoV-2/genética , SARS-CoV-2/química , SARS-CoV-2/metabolismo , RNA Viral/genética , RNA Viral/química , RNA Viral/metabolismo , Sítios de Ligação , Espectroscopia de Ressonância Magnética/métodos , Regiões 3' não Traduzidas , Ligantes , Humanos , Mutação , COVID-19/virologia , Pareamento de Bases , Motivos de Nucleotídeos
3.
Nucleic Acids Res ; 52(W1): W140-W147, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38769064

RESUMO

Genomic variation can impact normal biological function in complex ways and so understanding variant effects requires a broad range of data to be coherently assimilated. Whilst the volume of human variant data and relevant annotations has increased, the corresponding increase in the breadth of participating fields, standards and versioning mean that moving between genomic, coding, protein and structure positions is increasingly complex. In turn this makes investigating variants in diverse formats and assimilating annotations from different resources challenging. ProtVar addresses these issues to facilitate the contextualization and interpretation of human missense variation with unparalleled flexibility and ease of accessibility for use by the broadest range of researchers. By precalculating all possible variants in the human proteome it offers near instantaneous mapping between all relevant data types. It also combines data and analyses from a plethora of resources to bring together genomic, protein sequence and function annotations as well as structural insights and predictions to better understand the likely effect of missense variation in humans. It is offered as an intuitive web server https://www.ebi.ac.uk/protvar where data can be explored and downloaded, and can be accessed programmatically via an API.


Assuntos
Mutação de Sentido Incorreto , Software , Humanos , Bases de Dados de Proteínas , Anotação de Sequência Molecular , Proteoma/genética , Proteínas/genética , Proteínas/química , Internet , Genômica/métodos
4.
J Virol ; 98(8): e0023124, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38980063

RESUMO

African swine fever virus (ASFV) is the causative agent of a contagious disease affecting wild and domestic swine. The function of B169L protein, as a potential integral structural membrane protein, remains to be experimentally characterized. Using state-of-the-art bioinformatics tools, we confirm here earlier predictions indicating the presence of an integral membrane helical hairpin, and further suggest anchoring of this protein to the ER membrane, with both terminal ends facing the lumen of the organelle. Our evolutionary analysis confirmed the importance of purifying selection in the preservation of the identified domains during the evolution of B169L in nature. Also, we address the possible function of this hairpin transmembrane domain (HTMD) as a class IIA viroporin. Expression of GFP fusion proteins in the absence of a signal peptide supported B169L insertion into the ER as a Type III membrane protein and the formation of oligomers therein. Overlapping peptides that spanned the B169L HTMD were reconstituted into ER-like membranes and the adopted structures analyzed by infrared spectroscopy. Consistent with the predictions, B169L transmembrane sequences adopted α-helical conformations in lipid bilayers. Moreover, single vesicle permeability assays demonstrated the assembly of lytic pores in ER-like membranes by B169L transmembrane helices, a capacity confirmed by ion-channel activity measurements in planar bilayers. Emphasizing the relevance of these observations, pore-forming activities were not observed in the case of transmembrane helices derived from EP84R, another ASFV protein predicted to anchor to membranes through a α-helical HTMD. Overall, our results support predictions of viroporin-like function for the B169L HTMD.IMPORTANCEAfrican swine fever (ASF), a devastating disease affecting domestic swine, is widely spread in Eurasia, producing significant economic problems in the pork industry. Approaches to prevent/cure the disease are mainly restricted to the limited information concerning the role of most of the genes encoded by the large (160-170 kba) virus genome. In this report, we present the experimental data on the functional characterization of the African swine fever virus (ASFV) gene B169L. Data presented here indicates that the B169L gene encodes for an essential membrane-associated protein with a viroporin function.


Assuntos
Vírus da Febre Suína Africana , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/metabolismo , Animais , Suínos , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/virologia , Domínios Proteicos , Proteínas Viroporinas/metabolismo , Proteínas Viroporinas/genética , Febre Suína Africana/virologia , Febre Suína Africana/metabolismo , Proteínas Virais/metabolismo , Proteínas Virais/genética , Proteínas Virais/química , Sequência de Aminoácidos
5.
Bioinformatics ; 40(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39051707

RESUMO

SUMMARY: Most tools for normalizing NanoString gene expression data, apart from the default NanoString nCounter software, are R packages that focus on technical normalization and lack configurable parameters. However, content normalization is the most sensitive, experiment-specific, and relevant step to preprocess NanoString data. Currently this step requires the use of multiple tools and a deep understanding of data management by the researcher. We present GUANIN, a comprehensive normalization tool that integrates both new and well-established methods, offering a wide variety of options to introduce, filter, choose, and evaluate reference genes for content normalization. GUANIN allows the introduction of genes from an endogenous subset as reference genes, addressing housekeeping-related selection problems. It performs a specific and straightforward normalization approach for each experiment, using a wide variety of parameters with suggested default values. GUANIN provides a large number of informative output files that enable the iterative refinement of the normalization process. In terms of normalization, GUANIN matches or outperforms other available methods. Importantly, it allows researchers to interact comprehensively with the data preprocessing step without programming knowledge, thanks to its easy-to-use Graphical User Interface (GUI). AVAILABILITY AND IMPLEMENTATION: GUANIN can be installed with pip install GUANIN and it is available at https://pypi.org/project/guanin/. Source code, documentation, and case studies are available at https://github.com/julimontoto/guanin under the GPLv3 license.


Assuntos
Software , Perfilação da Expressão Gênica/métodos , Humanos , Interface Usuário-Computador
6.
J Proteome Res ; 23(7): 2518-2531, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38810119

RESUMO

Phosphorylation is the most studied post-translational modification, and has multiple biological functions. In this study, we have reanalyzed publicly available mass spectrometry proteomics data sets enriched for phosphopeptides from Asian rice (Oryza sativa). In total we identified 15,565 phosphosites on serine, threonine, and tyrosine residues on rice proteins. We identified sequence motifs for phosphosites, and link motifs to enrichment of different biological processes, indicating different downstream regulation likely caused by different kinase groups. We cross-referenced phosphosites against the rice 3,000 genomes, to identify single amino acid variations (SAAVs) within or proximal to phosphosites that could cause loss of a site in a given rice variety and clustered the data to identify groups of sites with similar patterns across rice family groups. The data has been loaded into UniProt Knowledge-Base─enabling researchers to visualize sites alongside other data on rice proteins, e.g., structural models from AlphaFold2, PeptideAtlas, and the PRIDE database─enabling visualization of source evidence, including scores and supporting mass spectra.


Assuntos
Genoma de Planta , Oryza , Fosfoproteínas , Proteínas de Plantas , Proteômica , Transdução de Sinais , Oryza/genética , Oryza/metabolismo , Oryza/química , Proteômica/métodos , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/química , Fosfoproteínas/análise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Fosfopeptídeos/metabolismo , Fosfopeptídeos/análise , Bases de Dados de Proteínas , Motivos de Aminoácidos , Espectrometria de Massas
7.
Stroke ; 55(4): 1062-1074, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38436063

RESUMO

BACKGROUND: In preterm birth germinal matrix hemorrhages (GMHs) and the consequent posthemorrhagic hydrocephalus (PHH), the neuroepithelium/ependyma development is disrupted. This work is aimed to explore the possibilities of ependymal repair in GMH/PHH using a combination of neural stem cells, ependymal progenitors (EpPs), and mesenchymal stem cells. METHODS: GMH/PHH was induced in 4-day-old mice using collagenase, blood, or blood serum injections. PHH severity was characterized 2 weeks later using magnetic resonance, immunofluorescence, and protein expression quantification with mass spectrometry. Ependymal restoration and wall regeneration after stem cell treatments were tested in vivo and in an ex vivo experimental approach using ventricular walls from mice developing moderate and severe GMH/PHH. The effect of the GMH environment on EpP differentiation was tested in vitro. Two-tailed Student t or Wilcoxon-Mann-Whitney U test was used to find differences between the treated and nontreated groups. ANOVA and Kruskal-Wallis tests were used to compare >2 groups with post hoc Tukey and Dunn multiple comparison tests, respectively. RESULTS: PHH severity was correlated with the extension of GMH and ependymal disruption (means, 88.22% severe versus 19.4% moderate). GMH/PHH hindered the survival rates of the transplanted neural stem cells/EpPs. New multiciliated ependymal cells could be generated from transplanted neural stem cells and more efficiently from EpPs (15% mean increase). Blood and TNFα (tumor necrosis factor alpha) negatively affected ciliogenesis in cells committed to ependyma differentiation (expressing Foxj1 [forkhead box J1] transcription factor). Pretreatment with mesenchymal stem cells improved the survival rates of EpPs and ependymal differentiation while reducing the edematous (means, 18% to 0.5% decrease in severe edema) and inflammatory conditions in the explants. The effectiveness of this therapeutical strategy was corroborated in vivo (means, 29% to 0% in severe edema). CONCLUSIONS: In GMH/PHH, the ependyma can be restored and edema decreased from either neural stem cell or EpP transplantation in vitro and in vivo. Mesenchymal stem cell pretreatment improved the success of the ependymal restoration.


Assuntos
Doenças Fetais , Hidrocefalia , Células-Tronco Neurais , Nascimento Prematuro , Humanos , Feminino , Animais , Camundongos , Epêndima/patologia , Hidrocefalia/cirurgia , Hidrocefalia/metabolismo , Hemorragia Cerebral/terapia , Hemorragia Cerebral/metabolismo , Edema
8.
Neuroimage ; 297: 120695, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38942101

RESUMO

BACKGROUND: The prediction of Alzheimer's disease (AD) progression from its early stages is a research priority. In this context, the use of Artificial Intelligence (AI) in AD has experienced a notable surge in recent years. However, existing investigations predominantly concentrate on distinguishing clinical phenotypes through cross-sectional approaches. This study aims to investigate the potential of modeling additional dimensions of the disease, such as variations in brain metabolism assessed via [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET), and utilize this information to identify patients with mild cognitive impairment (MCI) who will progress to dementia (pMCI). METHODS: We analyzed data from 1,617 participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) who had undergone at least one FDG-PET scan. We identified the brain regions with the most significant hypometabolism in AD and used Deep Learning (DL) models to predict future changes in brain metabolism. The best-performing model was then adapted under a multi-task learning framework to identify pMCI individuals. Finally, this model underwent further analysis using eXplainable AI (XAI) techniques. RESULTS: Our results confirm a strong association between hypometabolism, disease progression, and cognitive decline. Furthermore, we demonstrated that integrating data on changes in brain metabolism during training enhanced the models' ability to detect pMCI individuals (sensitivity=88.4%, specificity=86.9%). Lastly, the application of XAI techniques enabled us to delve into the brain regions with the most significant impact on model predictions, highlighting the importance of the hippocampus, cingulate cortex, and some subcortical structures. CONCLUSION: This study introduces a novel dimension to predictive modeling in AD, emphasizing the importance of projecting variations in brain metabolism under a multi-task learning paradigm.


Assuntos
Encéfalo , Disfunção Cognitiva , Aprendizado Profundo , Progressão da Doença , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Humanos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Feminino , Masculino , Tomografia por Emissão de Pósitrons/métodos , Idoso , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Fluordesoxiglucose F18/farmacocinética , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Idoso de 80 Anos ou mais , Demência/diagnóstico por imagem , Demência/metabolismo , Inteligência Artificial , Neuroimagem/métodos
9.
Hippocampus ; 34(5): 241-260, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38415962

RESUMO

The medial temporal lobe (MTL) cortex, located adjacent to the hippocampus, is crucial for memory and prone to the accumulation of certain neuropathologies such as Alzheimer's disease neurofibrillary tau tangles. The MTL cortex is composed of several subregions which differ in their functional and cytoarchitectonic features. As neuroanatomical schools rely on different cytoarchitectonic definitions of these subregions, it is unclear to what extent their delineations of MTL cortex subregions overlap. Here, we provide an overview of cytoarchitectonic definitions of the entorhinal and parahippocampal cortices as well as Brodmann areas (BA) 35 and 36, as provided by four neuroanatomists from different laboratories, aiming to identify the rationale for overlapping and diverging delineations. Nissl-stained series were acquired from the temporal lobes of three human specimens (two right and one left hemisphere). Slices (50 µm thick) were prepared perpendicular to the long axis of the hippocampus spanning the entire longitudinal extent of the MTL cortex. Four neuroanatomists annotated MTL cortex subregions on digitized slices spaced 5 mm apart (pixel size 0.4 µm at 20× magnification). Parcellations, terminology, and border placement were compared among neuroanatomists. Cytoarchitectonic features of each subregion are described in detail. Qualitative analysis of the annotations showed higher agreement in the definitions of the entorhinal cortex and BA35, while the definitions of BA36 and the parahippocampal cortex exhibited less overlap among neuroanatomists. The degree of overlap of cytoarchitectonic definitions was partially reflected in the neuroanatomists' agreement on the respective delineations. Lower agreement in annotations was observed in transitional zones between structures where seminal cytoarchitectonic features are expressed less saliently. The results highlight that definitions and parcellations of the MTL cortex differ among neuroanatomical schools and thereby increase understanding of why these differences may arise. This work sets a crucial foundation to further advance anatomically-informed neuroimaging research on the human MTL cortex.


Assuntos
Lobo Temporal , Humanos , Lobo Temporal/patologia , Neuroanatomia/métodos , Masculino , Giro Para-Hipocampal/patologia , Giro Para-Hipocampal/diagnóstico por imagem , Feminino , Idoso , Córtex Entorrinal/patologia , Córtex Entorrinal/anatomia & histologia , Laboratórios , Idoso de 80 Anos ou mais
10.
Oncologist ; 29(5): 377-383, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38438322

RESUMO

Adult medulloblastoma (MB) is a rare disease affecting 0.6 persons per million adults over 19 years of age. The SHH-activated/TP53-wild type is the most common subtype, accounting for 60% of adult MBs, being characterized by mutations in PTCH1, SMO, or the TERT promoter. Several small studies demonstrate objective but short-lived responses to SMO inhibitors such as vismodegib or sonidegib. Like other oncogene-addicted solid tumors, detection of the corresponding drivers through liquid biopsy could aid in the molecular diagnosis and monitoring of the disease through less invasive procedures. However, most studies have only evaluated cerebrospinal fluid as the ctDNA reservoir, and very limited evidence exists on the role of liquid biopsy in plasma in patients with primary central nervous system tumors, including MB. We present the case of a 26-year-old patient with a recurrent MB, in which next-generation sequencing (FoundationOne CDx) revealed a mutation in PTCH1, allowing the patient to be treated with vismodegib in second line, resulting in a durable benefit lasting for 1 year. Using an in-house digital PCR probe, the PTCH1 mutation could be tracked in ctDNA during treatment with first-line chemotherapy and while on treatment with vismodegib, demonstrating a precise correlation with the radiological and clinical behavior of the disease.


Assuntos
Anilidas , DNA Tumoral Circulante , Meduloblastoma , Mutação , Receptor Patched-1 , Piridinas , Humanos , Meduloblastoma/tratamento farmacológico , Meduloblastoma/genética , Meduloblastoma/sangue , Meduloblastoma/patologia , Piridinas/uso terapêutico , Receptor Patched-1/genética , Adulto , Anilidas/uso terapêutico , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/sangue , Masculino , Feminino
11.
BMC Plant Biol ; 24(1): 58, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245701

RESUMO

BACKGROUND: Watermelon mosaic virus (WMV) is one of the most prevalent viruses affecting melon worldwide. Recessive resistance to WMV in melon has previously been reported in the African accession TGR-1551. Moreover, the genomic regions associated to the resistance have also been described. Nevertheless, the transcriptomic response that might infer the resistance to this potyvirus has not been explored. RESULTS: We have performed a comparative transcriptomic analysis using mock and WMV-inoculated plants of the susceptible cultivar "Bola de oro" (BO) and a resistant RIL (Recombinant inbred line) derived from the initial cross between "TGR-1551" and BO. In total, 616 genes were identified as differentially expressed and the weighted gene co-expression network analysis (WGCNA) detected 19 gene clusters (GCs), of which 7 were differentially expressed for the genotype x treatment interaction term. SNPs with a predicted high impact on the protein function were detected within the coding regions of most of the detected DEGs. Moreover, 3 and 16 DEGs were detected within the QTL regions previously described in chromosomes 11 and 5, respectively. In addition to these two specific genomic regions, we also observde large transcriptomic changes from genes spread across the genome in the resistant plants in response to the virus infection. This early response against WMV implied genes involved in plant-pathogen interaction, plant hormone signal transduction, the MAPK signaling pathway or ubiquitin mediated proteolysis, in detriment to the photosynthetic and basal metabolites pathways. Moreover, the gene MELO3C021395, which coded a mediator of RNA polymerase II transcription subunit 33A (MED33A), has been proposed as the candidate gene located on chromosome 11 conferring resistance to WMV. CONCLUSIONS: The comparative transcriptomic analysis presented here showed that, even though the resistance to WMV in TGR-1551 has a recessive nature, it triggers an active defense response at a transcriptomic level, which involves broad-spectrum resistance mechanisms. Thus, this study represents a step forward on our understanding of the mechanisms underlaying WMV resistance in melon. In addition, it sheds light into a broader topic on the mechanisms of recessive resistances.


Assuntos
Cucurbitaceae , Potyvirus , Cucurbitaceae/genética , Potyvirus/fisiologia , Perfilação da Expressão Gênica , Transcriptoma , Doenças das Plantas/genética
12.
Neuropathol Appl Neurobiol ; 50(1): e12962, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38343067

RESUMO

AIMS: According to Braak's hypothesis, it is plausible that Parkinson's disease (PD) originates in the enteric nervous system (ENS) and spreads to the brain through the vagus nerve. In this work, we studied whether inflammatory bowel diseases (IBDs) in humans can progress with the emergence of pathogenic α-synuclein (α-syn) in the gastrointestinal tract and midbrain dopaminergic neurons. METHODS: We have analysed the gut and the ventral midbrain from subjects previously diagnosed with IBD and form a DSS-based rat model of gut inflammation in terms of α-syn pathology. RESULTS: Our data support the existence of pathogenic α-syn in both the gut and the brain, thus reinforcing the potential role of the ENS as a contributing factor in PD aetiology. Additionally, we have analysed the effect of a DSS-based rat model of gut inflammation to demonstrate (i) the appearance of P-α-syn inclusions in both Auerbach's and Meissner's plexuses (gut), (ii) an increase in α-syn expression in the ventral mesencephalon (brain) and (iii) the degeneration of nigral dopaminergic neurons, which all are considered classical hallmarks in PD. CONCLUSION: These results strongly support the plausibility of Braak's hypothesis and emphasise the significance of peripheral inflammation and the gut-brain axis in initiating α-syn aggregation and transport to the substantia nigra, resulting in neurodegeneration.


Assuntos
Doenças Inflamatórias Intestinais , Doença de Parkinson , Humanos , Ratos , Animais , alfa-Sinucleína/metabolismo , Doença de Parkinson/patologia , Encéfalo/patologia , Inflamação/patologia , Neurônios Dopaminérgicos/metabolismo , Doenças Inflamatórias Intestinais/patologia
13.
Chemistry ; 30(13): e202303382, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38150600

RESUMO

In this work, the synthesis and characterization of a heterogeneous photocatalyst based on spherical silica nanoparticles superficially modified with anthraquinone 2-carboxylic acid (AQ-COOH) are presented. The nanomaterial was characterized by TEM, SEM, FT-IR, diffuse reflectance, fluorescence, NMR, DLS, XRD and XPS. These analyses confirm the covalent linking of AQ-COOH with the NH2 functionality in the nanomaterial and, more importantly, the photocatalyst retains its photophysical properties once bound. The heterogeneous photocatalyst was successfully employed in the aerobic hydroxylation of arylboronic acids to phenols under sustainable reaction conditions. Phenols were obtained in high yields (up to 100 %) with low catalyst loading (3.5 mol %), reaching TOF values of 3.7 h-1 . Using 2-propanol as solvent at room temperature, the visible light photocatalysis produced H2 O2 as a key intermediate to promote the aerobic hydroxylation of arylboronic acids. The heterogeneous photocatalyst was reused at least 5 times, without modification of the nanomaterial structure and morphology. This simple heterogeneous system showed great catalytic activity under sustainable reaction conditions.

14.
Brain Behav Immun ; 117: 135-148, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38211636

RESUMO

The mammalian hippocampus can generate new neurons throughout life. Known as adult hippocampal neurogenesis (AHN), this process participates in learning, memory, mood regulation, and forgetting. The continuous incorporation of new neurons enhances the plasticity of the hippocampus and contributes to the cognitive reserve in aged individuals. However, the integrity of AHN is targeted by numerous pathological conditions, including neurodegenerative diseases and sustained inflammation. In this regard, the latter causes cognitive decline, mood alterations, and multiple AHN impairments. In fact, the systemic administration of Lipopolysaccharide (LPS) from E. coli to mice (a model of sepsis) triggers depression-like behavior, impairs pattern separation, and decreases the survival, maturation, and synaptic integration of adult-born hippocampal dentate granule cells. Here we tested the capacity of the macrolide antibiotic azithromycin to neutralize the deleterious consequences of LPS administration in female C57BL6J mice. This antibiotic exerted potent neuroprotective effects. It reversed the increased immobility time during the Porsolt test, hippocampal secretion of pro-inflammatory cytokines, and AHN impairments. Moreover, azithromycin promoted the synaptic integration of adult-born neurons and functionally remodeled the gut microbiome. Therefore, our data point to azithromycin as a clinically relevant drug with the putative capacity to ameliorate the negative consequences of chronic inflammation by modulating AHN and hippocampal-related behaviors.


Assuntos
Azitromicina , Sepse , Feminino , Camundongos , Animais , Azitromicina/farmacologia , Lipopolissacarídeos/farmacologia , Escherichia coli , Hipocampo/patologia , Neurogênese/fisiologia , Antibacterianos/farmacologia , Inflamação/patologia , Mamíferos
15.
Anticancer Drugs ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941120

RESUMO

Patients with recurrent/metastatic (R/M) platinum-refractory squamous cell carcinoma of the head and neck (SCCHN) have fewer treatment options and harbor an especially poor prognosis. Maintaining treatment with anti-PD1 agents beyond response evaluation criteria in solid tumors-defined disease progression (TBP) has been shown to be efficacious in several solid tumors, including head and neck cancer. We present the case of a platinum-refractory locally recurrent, PD-L1-negative hypopharyngeal carcinoma, that received second-line nivolumab which was then maintained beyond progression under the following criteria: no Eastern Cooperative Oncology Group performance status deterioration, no rapidly progressive disease, no severe toxicity, and evidence of overall treatment benefit. The patient achieved a partial response 8 months after starting second-line nivolumab, with progressive disease at 26 months, then followed by the first TBP with nivolumab lasting for 15 months due to a new tumor progression. A second TBP with nivolumab lasting for 7 months, was followed by a third TBP with nivolumab for 12 months and achieving a major tumor response. Treatment is still ongoing 60 months after starting nivolumab, with excellent tolerance to therapy. Maintaining anti-PD1 agents beyond progression is an efficacious treatment option for patients with R/M SCCHN, that may achieve very durable disease control and even late major responses.

16.
Inorg Chem ; 63(23): 10648-10656, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38807360

RESUMO

Bimodal medical imaging based on magnetic resonance imaging (MRI) and computed tomography (CT) is a well-known strategy to increase the diagnostic accuracy. The most recent advances in MRI and CT instrumentation are related to the use of ultra-high magnetic fields (UHF-MRI) and different working voltages (spectral CT), respectively. Such advances require the parallel development of bimodal contrast agents (CAs) that are efficient under new instrumental conditions. In this work, we have synthesized, through a precipitation reaction from a glycerol solution of the precursors, uniform barium dysprosium fluoride nanospheres with a cubic fluorite structure, whose size was found to depend on the Ba/(Ba + Dy) ratio of the starting solution. Moreover, irrespective of the starting Ba/(Ba + Dy) ratio, the experimental Ba/(Ba + Dy) values were always lower than those used in the starting solutions. This result was assigned to lower precipitation kinetics of barium fluoride compared to dysprosium fluoride, as inferred from the detailed analysis of the effect of reaction time on the chemical composition of the precipitates. A sample composed of 34 nm nanospheres with a Ba0.51Dy0.49F2.49 stoichiometry showed a transversal relaxivity (r2) value of 147.11 mM-1·s-1 at 9.4 T and gave a high negative contrast in the phantom image. Likewise, it produced high X-ray attenuation in a large range of working voltages (from 80 to 140 kVp), which can be attributed to the presence of different K-edge values and high Z elements (Ba and Dy) in the nanospheres. Finally, these nanospheres showed negligible cytotoxicity for different biocompatibility tests. Taken together, these results show that the reported nanoparticles are excellent candidates for UHF-MRI/spectral CT bimodal imaging CAs.

17.
Eur J Pediatr ; 183(9): 3885-3895, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38896274

RESUMO

The assessment of body fat of children in primary care requires consideration of the dynamic changes in height, weight, lean mass, and fat mass during childhood growth. To achieve this, we aim to develop a predictive equation based on anthropometric values, with optimal diagnostic utility. This is a cross-sectional observational study, involving schoolgoers aged 11-17 years in the Vigo metropolitan area. Out of 10,747 individuals, 577 were randomly recruited. VARIABLES: age, sex, ethnicity/country of origin, weight, height, 8 skinfolds, 3 diameters, 7 perimeters, and 85% percentile of body fat mass as the gold standard. Generalized additive regression was selected by cross-validation and compared using receiver operating characteristic curves (ROC curves). Sensitivity, specificity, positive and negative predictive values, true positive and true negative values, false positive and false negative values, accuracy, and positive and negative likelihood ratios were calculated. Two models were identified. The optimal model includes sex, weight, height, leg perimeter, and arm perimeter, with sensitivity of 0.93 (0.83-1.00), specificity of 0.91 (0.83-0.96), accuracy of 0.91 (0.84-0.96), and area under the curve (AUC) of 0.957 (0.928-0.986). The second model includes sex, age, and body mass index, with sensitivity of 0.93 (0.81-1.00), specificity of 0.90 (0.80-0.97), accuracy of 0.90 (0.82-0.96), and an AUC of 0.944 (0.903-0.984). CONCLUSION: Two predictive models, with the 85th percentile of fat mass as the gold standard, built with basic anthropometric measures, show very high diagnostic utility parameters. Their calculation is facilitated by a complementary online calculator. WHAT IS KNOWN: • In routine clinical practice, mainly in primary care, BMI is used to determine overweight and obesity. This index has its weaknesses in the assessment of children. WHAT IS NEW: • We provide a calculator whose validated algorithm, through the determination of fat mass by impedanciometry, makes it possible to determine the risk of overweight and obesity in the community setting, through anthropometric measurements, providing a new practical, accessible and reliable model that improves the classification of overweight and obesity in children with respect to that obtained by determining BMI.


Assuntos
Obesidade Infantil , Humanos , Adolescente , Criança , Masculino , Feminino , Estudos Transversais , Espanha/epidemiologia , Obesidade Infantil/diagnóstico , Obesidade Infantil/epidemiologia , Índice de Massa Corporal , Curva ROC , Medição de Risco/métodos , Sensibilidade e Especificidade , Antropometria/métodos
18.
BMC Public Health ; 24(1): 790, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481210

RESUMO

BACKGROUND: Significant consequences of COVID-19 within academic/professional life are, at the psychological level, related to worry, tension, stress; coping strategies and lifestyle changes. This study describes the process of design and validation of an inventory (QPIC), which aims to assess the psychological impact that a situation of confinement can produce among university students and teachers. METHODS: Design of the instrument and psychometric tests. A sample of 862 students and 229 professors affiliated to Spanish and Colombian universities was used. Data were collected in April 2020 with the request of the favourable Bioethics Committee IR/2020. RESULTS: Six experts carried out the content validation. A confirmatory factor analysis of the theoretical dimensions proposed for the scales was performed and the internal consistency of each of the three initial scales was confirmed (0.866, 0.813 and 0.834). CONCLUSION: A rigorous and reliable instrument is achieved, consisting of two final scales: (a) Worry, tension and stress scale (b) Coping scale, which helps to measure individual psychological effects in housebound situations. It is an instrument designed, constructed ad hoc to assess the impact of confinement and subjected to validation. The factor structure and reliability of the instrument are examined and good psychometric properties are obtained. The application of this inventory will make it possible to assess the impact on people's mental health during a period of confinement.


Assuntos
COVID-19 , Saúde Mental , Humanos , Universidades , Reprodutibilidade dos Testes , Ansiedade , COVID-19/epidemiologia , Psicometria , Inquéritos e Questionários
19.
Mar Drugs ; 22(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39057411

RESUMO

In our continuing search for biologically active new chemical entities from marine organisms, we have isolated a new cyclic depsipeptide, PM170453 (1), from a cyanobacterium of the genus Lyngbya sp., collected in the Indo-Pacific Ocean. Structure elucidation of the isolated compound was determined by spectroscopic methods including MS, 1H, 13C and 2D-NMR. To solve the supply problem for 1 and progress pharmaceutical development, the total synthesis of 1 that involves a total of 20 chemical steps in a convergent process was carried out. Its in vitro cytotoxic activity against four human tumor cell lines, as well as the inhibition of the interaction between the programmed cell death protein 1 PD-1 and its ligand PD-L1 were also evaluated.


Assuntos
Antineoplásicos , Cianobactérias , Depsipeptídeos , Depsipeptídeos/farmacologia , Depsipeptídeos/isolamento & purificação , Depsipeptídeos/química , Depsipeptídeos/síntese química , Humanos , Cianobactérias/química , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/síntese química , Organismos Aquáticos , Antígeno B7-H1/antagonistas & inibidores , Oceano Pacífico , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação
20.
Int J Biometeorol ; 68(8): 1573-1585, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38661946

RESUMO

The availability of reliable information on local climatic-tourism conditions is a growing need due to the influence it exerts on the quality of the organizational strategy of tourist destination's, and travel experience. Evaluations of the tourism potential of the climate have been carried out on a daily or monthly resolution, thus limiting the collection of detailed information that makes it possible to fine-tune tourism management and operational decision-making on an intraday scale. This research is the first case study to analyse the climatic suitability for nature tourism, using the weather types method at hourly resolution. The study applies to arid tourist destinations in Isfahan province (Iran). The detailed resolution has made it possible to identify the time slots favourable to the development of nature tourism in those periods of the year recognized as critical in the daily resolution analyses. In the same way, the hourly resolution has also identified critical bands in those periods indicated as favourable in the evaluations to daily resolution. The hourly resolution provides detailed information that can allow tourists and also tourism managers to establish intraday adaptation strategies that make it possible to develop the activity even in places with extreme climates.


Assuntos
Clima Desértico , Turismo , Irã (Geográfico) , Tempo (Meteorologia) , Humanos , Clima
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