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1.
Trends Biotechnol ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304351

RESUMEN

Mangroves are impacted by multiple environmental stressors, including sea level rise, erosion, and plastic pollution. Thus, mangrove soil may be an excellent source of as yet unknown plastic-transforming microorganisms. Here, we assess the impact of polyethylene terephthalate (PET) particles and seawater intrusion on the mangrove soil microbiome and report an enrichment culture experiment to artificially select PET-transforming microbial consortia. The analysis of metagenome-assembled genomes of two bacterial consortia revealed that PET catabolism can be performed by multiple taxa, of which particular species harbored putative novel PET-active hydrolases. A key member of these consortia (Mangrovimarina plasticivorans gen. nov., sp. nov.) was found to contain two genes encoding monohydroxyethyl terephthalate hydrolases. This study provides insights into the development of strategies for harnessing soil microbiomes, thereby advancing our understanding of the ecology and enzymology involved in microbial-mediated PET transformations in marine-associated systems.

2.
Dalton Trans ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311756

RESUMEN

Methyl magnesium bromide is a precatalyst for the dehydrocoupling of silanes and amines to produce aminosilane products under mild conditions. As a commercially available Grignard reagent, this precatalyst represents a simplification over previous magnesium-containing catalysts for Si-N bond formation while displaying similar activity to other magnesium-based catalysts. This observation is consistent with the hypothesis that competitive Schlenk equilibrium can be addressed by not using an ancillary ligand. While the activity of MeMgBr is lower than some reported catalysts, including other commercially available precatalysts, unique selectivity was observed for MeMgBr that may allow for directed synthesis of aminosilane products. This work continues to increase the accessibility of Si-N heterodehydrocoupling through a growing family of commercially available precatalysts that balance activity and selectivity.

3.
Brain Commun ; 6(5): fcae269, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39258258

RESUMEN

Heatwaves have serious impacts on human health and constitute a key health concern from anthropogenic climate change. People have different individual tolerance for heatwaves or unaccustomed temperatures. Those with epilepsy may be particularly affected by temperature as the electroclinical hallmarks of brain excitability in epilepsy (inter-ictal epileptiform discharges and seizures) are influenced by a range of physiological and non-physiological conditions. Heatwaves are becoming more common and may affect brain excitability. Leveraging spontaneous heatwaves during periods of intracranial EEG recording in participants with epilepsy in a non-air-conditioned telemetry unit at the National Hospital for Neurology and Neurosurgery in London from May to August 2015-22, we examined the impact of heatwaves on brain excitability. In London, a heatwave is defined as three or more consecutive days with daily maximum temperatures ≥28°C. For each participant, we counted inter-ictal epileptiform discharges using four 10-min segments within, and outside of, heatwaves during periods of intracranial EEG recording. Additionally, we counted all clinical and subclinical seizures within, and outside of, heatwaves. We searched for causal rare genetic variants and calculated the epilepsy PRS. Nine participants were included in the study (six men, three women), median age 30 years (range 24-39). During heatwaves, there was a significant increase in the number of inter-ictal epileptiform discharges in three participants. Five participants had more seizures during the heatwave period, and as a group, there were significantly more seizures during the heatwaves. Genetic data, available for eight participants, showed none had known rare, genetically-determined epilepsies, whilst all had high polygenic risk scores for epilepsy. For some people with epilepsy, and not just those with known, rare, temperature-sensitive epilepsies, there is an association between heatwaves and increased brain excitability. These preliminary data require further validation and exploration, as they raise concerns about the impact of heatwaves directly on brain health.

4.
J Cereb Blood Flow Metab ; : 271678X241270445, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113414

RESUMEN

Although ischemia increases the abundance of plasminogen activator inhibitor-1 (PAI-1), its source and role in the ischemic brain remain unclear. We detected PAI-1-immunoreactive cells with morphological features of reactive astrocytes in the peri-ischemic cortex of mice after an experimentally-induced ischemic lesion, and of a chimpanzee that suffered a naturally-occurring stroke. We found that although the abundance of PAI-1 increases 24 hours after the onset of the ischemic injury in a non-reperfusion murine model of ischemic stroke, at that time-point there is no difference in astrocytic reactivity and the volume of the ischemic lesion between wild-type (Wt) animals and in mice either genetically deficient (PAI-1-/-) or overexpressing PAI-1 (PAI-1Tg). In contrast, 72 hours later astrocytic reactivity and the volume of the ischemic lesion were decreased in PAI-1-/- mice and increased in PAI-1Tg animals. Our immunoblottings and fractal analysis studies show that the abundance of astrocytic PAI-1 rises during the recovery phase from a hypoxic injury, which in turn increases the abundance of glial fibrillary acidic protein (GFAP) and triggers morphological features of reactive astrocytes. These studies indicate that cerebral ischemia-induced release of astrocytic PAI-1 triggers astrocytic reactivity associated with enlargement of the necrotic core.

5.
bioRxiv ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39185211

RESUMEN

Genome Wide Association studies (GWAS) have implicated PMS2 as a modifier of somatic expansion in Huntington's disease (HD), one of >45 known Repeat Expansion Diseases (REDs). PMS2 is a subunit of the MutLα complex, a major component of the mismatch repair (MMR) system, a repair pathway that is involved in the generation of expansions in many different REDs. However, while MLH3, a subunit of a second MutL complex, MutLγ, is required for all expansions, PMS2 has been shown to protect against expansion in some model systems but to drive expansion in others. To better understand PMS2's behavior, we have compared the effect of the loss of PMS2 in different tissues of an HD mouse model (CAG/CTG repeats) and a mouse model for the Fragile X-related disorders (FXDs), disorders that result from a CGG/CCG repeat expansion. Mice heterozygous for Pms2 show increased expansions in most expansion-prone tissues in both disease models. However, in Pms2 null mice expansions of both repeats increased in some tissues but decreased in others. Thus, the previously reported differences in the effects of PMS2 in different model systems do not reflect fundamentally different roles played by PMS2 in different REDs, but rather the paradoxical effects of PMS2 in different cellular contexts. These findings have important implications not only for the mechanism of expansion and the development of therapeutic approaches to reduce the pathology generated by repeat expansion, but also for our understanding of normal MMR.

6.
Biomedicines ; 12(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39200195

RESUMEN

Breast cancer (BRCA) remains a significant global health challenge due to its prevalence and lethality, exacerbated by the development of resistance to conventional therapies. Therefore, understanding the molecular mechanisms underpinning chemoresistance is crucial for improving therapeutic outcomes. Human deoxycytidine triphosphate pyrophosphatase 1 (DCTPP1) has emerged as a key player in various cancers, including BRCA. DCTPP1, involved in nucleotide metabolism and maintenance of genomic stability, has been linked to cancer cell proliferation, survival, and drug resistance. This study evaluates the role of DCTPP1 in BRCA prognosis and chemotherapy response. Data from the Cancer Genome Atlas Program (TCGA), Genotype-Tissue Expression (GTEx), and Gene Expression Omnibus (GEO) repositories, analyzed using GEPIA and Kaplan-Meier Plotter, indicate that high DCTPP1 expression correlates with poorer overall survival and increased resistance to chemotherapy in BRCA patients. Further analysis reveals that DCTPP1 gene expression is up-regulated in non-responders to chemotherapy, particularly in estrogen receptor (ER)-positive, luminal A subtype patients, with significant predictive power. Additionally, in vitro studies show that DCTPP1 gene expression increases in response to 5-fluorouracil and doxorubicin treatments in luminal A BRCA cell lines, suggesting a hypothetical role in chemoresistance. These findings highlight DCTPP1 as a potential biomarker for predicting chemotherapy response and as a therapeutic target to enhance chemotherapy efficacy in BRCA patients.

7.
J Med Chem ; 67(13): 11421-11434, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38943610

RESUMEN

Molecular chameleonicity may enable compounds to compensate for the unfavorable ADME properties typically associated with complex molecules, such as PROTACs. Here we present a few in silico strategies to implement chameleonicity considerations in drug design. Initially, we identified six structurally related CRBN-based PROTACs targeting BET proteins and experimentally verified whether chameleonicity is needed to obtain an acceptable physicochemical profile. Then, we utilized experimental data to validate our novel computational strategies based on tools crafted to encompass a spectrum of complexities and innovative features. After confirming that the formation of IMHBs is the primary driving factor behind chameleonicity, we initially utilized conformational sampling data to define cChameCS, an IMHB-mediated, simple, and rapid chameleonicity predictor index suitable for early drug discovery. Subsequently, we identified dynamic IMHB patterns relevant to chameleonicity through molecular dynamics simulations. Finally, we proposed a workflow for designing structurally related chameleonic PROTACs of potential application in the lead optimization process.


Asunto(s)
Diseño de Fármacos , Simulación de Dinámica Molecular , Humanos , Ubiquitina-Proteína Ligasas/metabolismo , Descubrimiento de Drogas , Quimera Dirigida a la Proteólisis , Proteínas Adaptadoras Transductoras de Señales
8.
ISME J ; 18(1)2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38896025

RESUMEN

The SeqCode is a new code of prokaryotic nomenclature that was developed to validate taxon names using genome sequences as the type material. The present article provides an independent view about the SeqCode, highlighting its history, current status, basic features, pros and cons, and use to date. We also discuss important topics to consider for validation of novel prokaryotic taxon names using genomes as the type material. Owing to significant advances in metagenomics and cultivation methods, hundreds of novel prokaryotic species are expected to be discovered in the coming years. This manuscript aims to stimulate and enrich the debate around the use of the SeqCode in the upcoming golden age of prokaryotic taxon discovery and systematics.


Asunto(s)
Bacterias , Metagenómica , Terminología como Asunto , Bacterias/clasificación , Bacterias/genética , Archaea/clasificación , Archaea/genética , Clasificación/métodos , Genoma Bacteriano , Filogenia
9.
Epilepsia ; 65(8): 2238-2247, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38829313

RESUMEN

Epilepsy's myriad causes and clinical presentations ensure that accurate diagnoses and targeted treatments remain a challenge. Advanced neurotechnologies are needed to better characterize individual patients across multiple modalities and analytical techniques. At the XVIth Workshop on Neurobiology of Epilepsy: Early Onset Epilepsies: Neurobiology and Novel Therapeutic Strategies (WONOEP 2022), the session on "advanced tools" highlighted a range of approaches, from molecular phenotyping of genetic epilepsy models and resected tissue samples to imaging-guided localization of epileptogenic tissue for surgical resection of focal malformations. These tools integrate cutting edge research, clinical data acquisition, and advanced computational methods to leverage the rich information contained within increasingly large datasets. A number of common challenges and opportunities emerged, including the need for multidisciplinary collaboration, multimodal integration, potential ethical challenges, and the multistage path to clinical translation. Despite these challenges, advanced epilepsy neurotechnologies offer the potential to improve our understanding of the underlying causes of epilepsy and our capacity to provide patient-specific treatment.


Asunto(s)
Epilepsia , Humanos , Epilepsia/diagnóstico , Epilepsia/diagnóstico por imagen , Epilepsia/fisiopatología , Epilepsia/genética , Neuroimagen/métodos
10.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38474109

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related death worldwide. It is commonly diagnosed in advanced stages and therapeutic interventions are typically constrained to systemic chemotherapy, which yields only modest clinical outcomes. In this review, we examine recent developments in targeted therapy tailored to address distinct molecular pathway alteration required for PDAC. Our review delineates the principal signaling pathways and molecular mechanisms implicated in the initiation and progression of PDAC. Subsequently, we provide an overview of prevailing guidelines, ongoing investigations, and prospective research trajectories related to targeted therapeutic interventions, drawing insights from randomized clinical trials and other pertinent studies. This review focus on a comprehensive examination of preclinical and clinical data substantiating the efficacy of these therapeutic modalities, emphasizing the potential of combinatorial regimens and novel therapies to enhance the quality of life for individuals afflicted with PDAC. Lastly, the review delves into the contemporary application and ongoing research endeavors concerning targeted therapy for PDAC. This synthesis serves to bridge the molecular elucidation of PDAC with its clinical implications, the evolution of innovative therapeutic strategies, and the changing landscape of treatment approaches.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Estudios Prospectivos , Calidad de Vida , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología , Transducción de Señal
11.
Drug Discov Today ; 29(4): 103917, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38360147

RESUMEN

A principal challenge in the discovery of proteolysis targeting chimeras (PROTACs) as oral medications is their bioavailability. To facilitate drug design, it is therefore essential to identify the chemical space where orally bioavailable PROTACs are more likely to be situated. To this aim, we extracted structure-bioavailability insights from published data using traditional 2D descriptors, thereby shedding light on their potential and limitations as drug design tools. Subsequently, we describe cutting-edge experimental, computational and hybrid design strategies based on 3D descriptors, which show promise for enhancing the probability of discovering PROTACs with high oral bioavailability.


Asunto(s)
Descubrimiento de Drogas , Quimera Dirigida a la Proteólisis , Proteolisis , Diseño de Fármacos , Disponibilidad Biológica
12.
Syst Appl Microbiol ; 47(1): 126485, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38211536

RESUMEN

An easy and straightforward way to engineer microbial environmental communities is by setting up liquid enrichment cultures containing a specific substrate as the sole source of carbon. Here, we analyzed twenty single-contig high-quality metagenome-assembled genomes (MAGs) retrieved from a microbial consortium (T6) that was selected by the dilution-to-stimulation approach using Andean soil as inoculum and lignocellulose as a selection pressure. Based on genomic metrics (e.g., average nucleotide and amino acid identities) and phylogenomic analyses, 15 out of 20 MAGs were found to represent novel bacterial species, with one of those (MAG_26) belonging to a novel genus closely related to Caenibius spp. (Sphingomonadaceae). Following the rules and requirements of the SeqCode, we propose the name Andeanibacterium colombiense gen. nov., sp. nov. for this taxon. A subsequent functional annotation of all MAGs revealed that MAG_7 (Pseudobacter hemicellulosilyticus sp. nov.) contains 20, 19 and 16 predicted genes from carbohydrate-active enzymes families GH43, GH2 and GH92, respectively. Its lignocellulolytic gene profile resembles that of MAG_2 (the most abundant member) and MAG_3858, both of which belong to the Sphingobacteriaceae family. Using a database that contains experimentally verified plastic-active enzymes (PAZymes), twenty-seven putative bacterial polyethylene terephthalate (PET)-active enzymes (i.e., alpha/beta-fold hydrolases) were detected in all MAGs. A maximum of five putative PETases were found in MAG_3858, and two PETases were found to be encoded by A. colombiense. In conclusion, we demonstrate that lignocellulose-enriched liquid cultures coupled with genome-resolved metagenomics are suitable approaches to unveil the hidden bacterial diversity and its polymer-degrading potential in Andean soil ecosystems.


Asunto(s)
Ecosistema , Suelo , Humanos , Filogenia , ARN Ribosómico 16S/genética , Bacterias , Bacteroidetes/genética , Metagenoma , Metagenómica
13.
Trends Biotechnol ; 42(3): 265-268, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37845169

RESUMEN

The design and study of active microbial consortia able to degrade plastics represent an exciting area of research toward the development of bio-based alternatives to efficiently transform plastic waste. This forum article discusses concepts and mechanisms to inform emerging strategies for engineering microbiomes to transform plastics under controlled settings.


Asunto(s)
Microbiota , Plásticos , Plásticos/metabolismo , Biodegradación Ambiental , Consorcios Microbianos
14.
Int Orthop ; 48(2): 555-561, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38019296

RESUMEN

PURPOSE: Main question The aim of this study is to describe and analyze the frequency of acute perioperative (intraoperatively and 30 days after) complications of open/MISS thoracolumbar spine surgery. Secondary questions A) Describe the treatment of choice for every kind of complication mentioned. B) Perform a bibliographic search and compare the complications described and their frequency with those studied in the manuscript. METHODS: A retrospective cohort of 816 patients undergoing spinal surgery over a two year period was analyzed. Acute complications of 59 patients are described whether those with a greater number of levels required longer periods of hospitalization. RESULTS: The frequency of acute complications was 7.2%. The most common was infection (2.7%), followed by dural tear (1.7%), and screw malpositioning (1%), which is consistent with the current literature. No statistically significant results were observed when comparing the mean length of hospital stay among patients operated on a greater number of levels compared to the rest (P: 0.344; 95% CI: -3.88-10.93). CONCLUSIONS: The subsidiary patient of spinal surgery is getting older and has more comorbidities, and therefore, has a higher risk of complications. Although there are models predicting the risk of complications, they are not used in routine clinical practice. It would be necessary to unify the main criteria and establish guidelines for risk detection and therapeutic algorithms based on new high-quality studies.


Asunto(s)
Fusión Vertebral , Humanos , Estudios Retrospectivos , Fusión Vertebral/efectos adversos , Fusión Vertebral/métodos , Procedimientos Neuroquirúrgicos/métodos , Descompresión Quirúrgica/métodos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Vértebras Lumbares/cirugía
15.
Psychol Sport Exerc ; 67: 102429, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37665882

RESUMEN

The aim of this study was to explore how situational variables affect youth soccer players' perceived exertion (RPE) after official matches. Thirty-five elite youth male players (14.33 ± 0.86 years; 173.49 ± 6.16 cm; 63.44 ± 5.98 kg) who belonged to two different teams of a professional club participated in this study. Data collection was conducted during two seasons (2016-2017, 2017-2018) and included 60 official matches (30 official matches per team). Ten minutes after each match players rated their RPE and using a modified Borg CR-10 scale. A Random Forest Regression was used to quantify the importance of match-related situational variables in RPE. Afterwards, a linear mixed model analysis was applied to identify the variability in RPE among the situational variables. The game-playing time, the player status (starter or substitute) and the player identity were the strongest predictors of RPE. Moreover, the match outcome and the final scoreline showed significant effects on both starter and substitute players but the main effect of the quality of the opponent was only identified in starter players (p < 0.05). These results allow practitioners to know how situational variables interact and modulate RPE after official matches and help them to prescribe and adapt the players' training content and load before and after matches.


Asunto(s)
Artículos Domésticos , Fútbol , Adolescente , Humanos , Masculino , Esfuerzo Físico , Bosques Aleatorios , Recolección de Datos
16.
Chemistry ; 29(66): e202302618, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-37728424

RESUMEN

Group I alkoxides are highly active precatalysts in the heterodehydrocoupling of silanes and amines to afford aminosilane products. The broadly soluble and commercially available KOt Amyl was utilized as the benchmark precatalyst for this transformation. Challenging substrates such as anilines were found to readily couple primary, secondary, and tertiary silanes in high conversions (>90 %) after only 2 h at 40 °C. Traditionally challenging silanes such as Ph3 SiH were also easily coupled to simple primary and secondary amines under mild conditions, with reactivity that rivals many rare earth and transition-metal catalysts for this transformation. Preliminary evidence suggests the formation of hypercoordinated intermediates, but radicals were detected under catalytic conditions, indicating a mechanism that is rare for Si-N bond formation.

17.
Cells ; 12(18)2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37759487

RESUMEN

Over the past decade, adeno-associated viruses (AAVs) have attained significant prominence in gene therapy and genome editing applications, necessitating the development of robust and precise methodologies to ensure the quality and purity of AAV products. Existing AAV characterization techniques have proven effective for the analysis of pure and homogeneous AAV samples. However, there is still a demand for a rapid and low-sample-consumption method suitable for the characterization of lower purity or heterogeneous AAV samples commonly encountered in AAV products. Addressing this challenge, we propose the SEC-MP method, which combines size exclusion chromatography (SEC) with mass photometry (MP). In this novel approach, SEC effectively separates monomeric AAV particles from impurities, while the UV detector determines the virus particle concentration. MP complements this process by estimating the fraction of fully packaged AAVs in the total population of AAV particles. This combined methodology enables accurate determination of the titer of effective, fully packaged AAVs in samples containing aggregates, incorrectly packaged AAVs with incomplete genomes, protein or DNA fragments, and other impurities. Our experimental results demonstrate that SEC-MP provides valuable guidance for sample quality control and subsequent applications in the field of AAV research.

19.
Dalton Trans ; 52(38): 13497-13506, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37605890

RESUMEN

A family of commercially available organolithium compounds were found to effectively catalyze the heterodehydrocoupling of silanes and amines under ambient conditions. Ubiquitous nBuLi (1) was utilized as the benchmark catalyst, where an array of primary, secondary, and tertiary arylsilanes were coupled to electron-donating amines, affording aminosilanes in high conversions with short reaction times. Preliminary mechanistic analysis is consistent with a nucleophilic-type system that involves the formation of a hypervalent silicon intermediate. This work underscores the accessibility of Si-N heterodehydrocoupling, with organolithium reagents emerging as some of the most straightforward and cost-effective precatalysts for this transformation.

20.
J Med Chem ; 66(15): 10681-10693, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37490408

RESUMEN

New chemical modalities in drug discovery include molecules belonging to the bRo5 chemical space. Because of their complex and flexible structure, bRo5 compounds often suffer from a poor solubility/permeability profile. Chameleonicity describes the capacity of a molecule to adapt to the environment through conformational changes; the design of molecular chameleons is a medicinal chemistry strategy simultaneously optimizing solubility and permeability. A default method to quantify chameleonicity in early drug discovery is still missing. Here we introduce Chamelogk, an automated, fast, and cheap chromatographic descriptor of chameleonicity. Moreover, we report measurements for 55 Ro5 and bRo5 compounds and validate our method with literature data. Then, selected case studies (macrocycles, nonmacrocyclic compounds, and PROTACs) are used to illustrate the application of Chamelogk in combination with lipophilicity (BRlogD) and polarity (Δ log kwIAM) descriptors. Overall, we show how Chamelogk deserves being included in property-based drug discovery strategies to design oral bioavailable bRo5 compounds.


Asunto(s)
Química Farmacéutica , Descubrimiento de Drogas , Solubilidad , Permeabilidad , Preparaciones Farmacéuticas
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