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1.
Dalton Trans ; 53(20): 8642-8656, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38695637

RESUMEN

The new hydrazine 5H-dibenzo[b,f]azepin-5-amine (2) reacts with P- and Si-electrophiles via deprotonation to afford P(III)-, P(V)-, and TMS-hydrazides 3-8 and with carbonyl electrophiles via acid-free condensation to the N-substituted hydrazones 9-12 that are potential N-alkene ligands. While ß-ketohydrazone 9 and α-dihydrazone 10 react with [Mes(Cu)]4, [Cu(NCCCH3)4]2PF6, and FeCl2(THF)1.5 to afford complexes devoid of alkene interaction, [Cu(OTf)]2·C6H6 reacts with the α-keto hydrazone 11 or with N,N dimethyl-hydrazone 12 to form the neutral dimeric Cu(I) complex 18 with bridging Cu(I)-alkene interactions or the tetrahedral cationic complex 19 in which 12 binds as a bidentate hydrazone-alkene ligand, respectively. The surprising stability of the alkene coordination in complexes 18 and 19 prevents substitutions with, e.g., PPh3.

2.
Sci Adv ; 10(13): eadm9859, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38536921

RESUMEN

Loss-of-function mutations in KEAP1 frequently occur in lung cancer and are associated with poor prognosis and resistance to standard of care treatment, highlighting the need for the development of targeted therapies. We previously showed that KEAP1 mutant tumors consume glutamine to support the metabolic rewiring associated with NRF2-dependent antioxidant production. Here, using preclinical patient-derived xenograft models and antigenic orthotopic lung cancer models, we show that the glutamine antagonist prodrug DRP-104 impairs the growth of KEAP1 mutant tumors. We find that DRP-104 suppresses KEAP1 mutant tumors by inhibiting glutamine-dependent nucleotide synthesis and promoting antitumor T cell responses. Using multimodal single-cell sequencing and ex vivo functional assays, we demonstrate that DRP-104 reverses T cell exhaustion, decreases Tregs, and enhances the function of CD4 and CD8 T cells, culminating in an improved response to anti-PD1 therapy. Our preclinical findings provide compelling evidence that DRP-104, currently in clinical trials, offers a promising therapeutic approach for treating patients with KEAP1 mutant lung cancer.


Asunto(s)
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Glutamina/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/genética , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Inhibidores Enzimáticos/uso terapéutico , Mutación
3.
J Org Chem ; 88(23): 16144-16154, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37944159

RESUMEN

Inversion barriers ΔG‡ for planar chiral phosphine-alkene and sulfonamide-alkene hybrid ligands based on phenyl-dibenz[b,f]azepine have been determined by density-functional theory calculations. Analysis of the structural and electronic characteristics of the minima and transition states explains the magnitudes of ΔG‡ and the geometrical changes during the inversion process. The steric repulsion caused by bulky substituents attached to the azepine nitrogen atom has a pronounced effect on the ΔG‡ value, explaining, inter alia, the stereochemical stability of the P- and S-alkene ligands when compared to the fluxional parent compound where X = H.

4.
Chem Commun (Camb) ; 59(93): 13879-13882, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37933531

RESUMEN

Cu(I)-Hydrido complexes supported by dibenzo[b,f]azepinyl P-alkene hybrid ligands and stabilized by electrostatic interactions in a Cu-H⋯KCl⋯BR3 arrangement can be trapped with CO2 at low temperature to afford Cu(I)-formates. The complexes are isolable with and without a pendant BEt3 group and show strong Cu-O and weak B-O interactions.

5.
Chem Commun (Camb) ; 59(97): 14451-14454, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37982441

RESUMEN

Alkene planar chirality is introduced in the 'privileged' P-alkene phosphoramidite ligand 1. The resulting diastereomeric ligands (pR,R)-5 and (pS,R)-5 form optically pure complexes of Rh(I) and Pd(II), which catalyze conjugate additions of boron C-nucleophiles to enones and allylic alkylations, respectively. In the Rh-catalyzed reaction, the planar chirality of the alkene exerts absolute enantiocontrol over the potent BINOL auxiliary.

6.
Cell Rep ; 42(11): 113295, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37889752

RESUMEN

Lung cancer treatment has benefited greatly through advancements in immunotherapies. However, immunotherapy often fails in patients with specific mutations like KEAP1, which are frequently found in lung adenocarcinoma. We established an antigenic lung cancer model and used it to explore how Keap1 mutations remodel the tumor immune microenvironment. Using single-cell technology and depletion studies, we demonstrate that Keap1-mutant tumors diminish dendritic cell and T cell responses driving immunotherapy resistance. This observation was corroborated in patient samples. CRISPR-Cas9-mediated gene targeting revealed that hyperactivation of the NRF2 antioxidant pathway is responsible for diminished immune responses in Keap1-mutant tumors. Importantly, we demonstrate that combining glutaminase inhibition with immune checkpoint blockade can reverse immunosuppression, making Keap1-mutant tumors susceptible to immunotherapy. Our study provides new insight into the role of KEAP1 mutations in immune evasion, paving the way for novel immune-based therapeutic strategies for KEAP1-mutant cancers.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Evasión Inmune , Línea Celular Tumoral , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/terapia , Adenocarcinoma del Pulmón/metabolismo , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamiento farmacológico , Mutación/genética , Inmunoterapia , Microambiente Tumoral
7.
PLoS One ; 18(9): e0291056, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37669303

RESUMEN

The technological transformation and advertising utilized in the footwear industry significantly impact purchasing decisions. The gait properties, barefoot and with shoes, change depending on the footwear structure. The aim of this work is the biomechanical analysis of walking barefoot and with different sports shoes in a controlled group of 12 children between 4 and 6 years old. Kinematic and spatiotemporal variables were analyzed using a BTS motion capture analysis system with the Helen Hayes protocol. Previously, a survey was carried out with 262 families with children between 4 and 6 years old to justify the choice of footwear for this study. No significant differences were found between any of the measured conditions. The kinematic results showed significant differences in the ankle (right sagittal plane p = 0.04, left p < 0.01; right frontal plane p < 0.01, left p < 0.01), knee (right and left sagittal plane p < 0.01) and hip (right sagittal plane p < 0.01, left p = 0.04; right frontal plane p = 0.03). Additionally, the post hoc analysis revealed significant differences between barefoot gait and different footwear. The footwear used for this study and each one's various characteristics are not preponderant in the spatiotemporal and kinematic parameters of the children's gait. Thus, the footwear purchase may be conditioned by its design or composition and other properties may not be relevant.


Asunto(s)
Publicidad , Articulación del Tobillo , Humanos , Niño , Preescolar , Marcha , Industrias , Articulación de la Rodilla
8.
Cell Host Microbe ; 31(9): 1427-1430, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37708850

RESUMEN

T cell responses are important for the control of acute HIV infection but become progressively dysfunctional. In this issue of Cell Host & Microbe, Dubé et al. and Takata et al. provide insights into their ongoing interplay with persistent HIV reservoirs, with implications for harnessing functional, durable responses to eliminate HIV.


Asunto(s)
Infecciones por VIH , Humanos , Linfocitos T
9.
bioRxiv ; 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37502974

RESUMEN

Tumor mutations can influence the surrounding microenvironment leading to suppression of anti-tumor immune responses and thereby contributing to tumor progression and failure of cancer therapies. Here we use genetically engineered lung cancer mouse models and patient samples to dissect how LKB1 mutations accelerate tumor growth by reshaping the immune microenvironment. Comprehensive immune profiling of LKB1 -mutant vs wildtype tumors revealed dramatic changes in myeloid cells, specifically enrichment of Arg1 + interstitial macrophages and SiglecF Hi neutrophils. We discovered a novel mechanism whereby autocrine LIF signaling in Lkb1 -mutant tumors drives tumorigenesis by reprogramming myeloid cells in the immune microenvironment. Inhibiting LIF signaling in Lkb1 -mutant tumors, via gene targeting or with a neutralizing antibody, resulted in a striking reduction in Arg1 + interstitial macrophages and SiglecF Hi neutrophils, expansion of antigen specific T cells, and inhibition of tumor progression. Thus, targeting LIF signaling provides a new therapeutic approach to reverse the immunosuppressive microenvironment of LKB1 -mutant tumors.

10.
bioRxiv ; 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37425844

RESUMEN

Loss-of-function mutations in KEAP1 frequently occur in lung cancer and are associated with resistance to standard of care treatment, highlighting the need for the development of targeted therapies. We have previously shown that KEAP1 mutant tumors have increased glutamine consumption to support the metabolic rewiring associated with NRF2 activation. Here, using patient-derived xenograft models and antigenic orthotopic lung cancer models, we show that the novel glutamine antagonist DRP-104 impairs the growth of KEAP1 mutant tumors. We find that DRP-104 suppresses KEAP1 mutant tumor growth by inhibiting glutamine-dependent nucleotide synthesis and promoting anti-tumor CD4 and CD8 T cell responses. Using multimodal single-cell sequencing and ex vivo functional assays, we discover that DRP-104 reverses T cell exhaustion and enhances the function of CD4 and CD8 T cells culminating in an improved response to anti-PD1 therapy. Our pre-clinical findings provide compelling evidence that DRP-104, currently in phase 1 clinical trials, offers a promising therapeutic approach for treating patients with KEAP1 mutant lung cancer. Furthermore, we demonstrate that by combining DRP-104 with checkpoint inhibition, we can achieve suppression of tumor intrinsic metabolism and augmentation of anti-tumor T cell responses.

11.
Methods Mol Biol ; 2666: 317-346, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37166674

RESUMEN

Live cell-based SELEX (Systematic Evolution of Ligand EXponential enrichment) is a promising approach for identifying aptamers that can selectively bind to a cell-surface receptor or recognize a particular target cell population. In particular, it offers a facile selection strategy for some special cell-surface proteins that are originally glycosylated or heavily posttranslationally modified and are unavailable in their native/active conformation after in vitro expression and purification. In this chapter, we describe a generalized procedure for evolution of cell type-specific RNA aptamers targeting a cell membrane bound target by combining the live cell-based SELEX strategy with high-throughput sequencing (HTS) and bioinformatics analysis.


Asunto(s)
Aptámeros de Nucleótidos , Aptámeros de Nucleótidos/genética , Aptámeros de Nucleótidos/metabolismo , Técnica SELEX de Producción de Aptámeros/métodos , Biología Computacional , Ligandos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
12.
Alzheimers Dement ; 19(9): 4046-4060, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37204054

RESUMEN

INTRODUCTION: Latin American Initiative for Lifestyle Intervention to Prevent Cognitive Decline (LatAm-FINGERS) is the first non-pharmacological multicenter randomized clinical trial (RCT) to prevent cognitive impairment in Latin America (LA). Our aim is to present the study design and discuss the strategies used for multicultural harmonization. METHODS: This 1-year RCT (working on a 1-year extension) investigates the feasibility of a multi-domain lifestyle intervention in LA and the efficacy of the intervention, primarily on cognitive function. An external harmonization process was carried out to follow the FINGER model, and an internal harmonization was performed to ensure this study was feasible and comparable across the 12 participating LA countries. RESULTS: Currently, 1549 participants have been screened, and 815 randomized. Participants are ethnically diverse (56% are Nestizo) and have high cardiovascular risk (39% have metabolic syndrome). DISCUSSION: LatAm-FINGERS overcame a significant challenge to combine the region's diversity into a multi-domain risk reduction intervention feasible across LA while preserving the original FINGER design.


Asunto(s)
Disfunción Cognitiva , Humanos , América Latina , Disfunción Cognitiva/prevención & control , Estilo de Vida , Cognición , Proyectos de Investigación
13.
medRxiv ; 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-33907755

RESUMEN

SARS-CoV-2 infection and vaccination elicit potent immune responses. Our study presents a comprehensive multimodal single-cell dataset of peripheral blood of patients with acute COVID-19 and of healthy volunteers before and after receiving the SARS-CoV-2 mRNA vaccine and booster. We compared host immune responses to the virus and vaccine using transcriptional profiling, coupled with B/T cell receptor repertoire reconstruction. COVID-19 patients displayed an enhanced interferon signature and cytotoxic gene upregulation, absent in vaccine recipients. These findings were validated in an independent dataset. Analysis of B and T cell repertoires revealed that, while the majority of clonal lymphocytes in COVID-19 patients were effector cells, clonal expansion was more evident among circulating memory cells in vaccine recipients. Furthermore, while clonal αß T cell responses were observed in both COVID-19 patients and vaccine recipients, dramatic expansion of clonal γδT cells was found only in infected individuals. Our dataset enables comparative analyses of immune responses to infection versus vaccination, including clonal B and T cell responses. Integrating our data with publicly available datasets allowed us to validate our findings in larger cohorts. To our knowledge, this is the first dataset to include comprehensive profiling of longitudinal samples from healthy volunteers pre/post SARS-CoV-2 vaccine and booster.

14.
iScience ; 26(12): 108572, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38213787

RESUMEN

SARS-CoV-2 infection and vaccination elicit potent immune responses. Our study presents a comprehensive multimodal single-cell analysis of blood from COVID-19 patients and healthy volunteers receiving the SARS-CoV-2 vaccine and booster. We profiled immune responses via transcriptional analysis and lymphocyte repertoire reconstruction. COVID-19 patients displayed an enhanced interferon signature and cytotoxic gene upregulation, absent in vaccine recipients. B and T cell repertoire analysis revealed clonal expansion among effector cells in COVID-19 patients and memory cells in vaccine recipients. Furthermore, while clonal αß T cell responses were observed in both COVID-19 patients and vaccine recipients, expansion of clonal γδ T cells was found only in infected individuals. Our dataset enables side-by-side comparison of immune responses to infection versus vaccination, including clonal B and T cell responses. Our comparative analysis shows that vaccination induces a robust, durable clonal B and T cell responses, without the severe inflammation associated with infection.

16.
Trop Dis Travel Med Vaccines ; 8(1): 15, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35773710

RESUMEN

BACKGROUND: Leishmaniasis is a vector-borne disease caused by several species from genus Leishmania. An increase in the number of cases related to human movement has been informed in the last years. Due to the increase of suspicious leishmaniasis cases arriving in Cuba during 2017, a general analysis is presented herein. METHODS: Clinical samples were collected from 5 patients suspicious of leishmaniasis, received from January to December 2017 at the Institute of Tropical Medicine Pedro Kourí, Cuba. Skin lesion samples were analyzed using different diagnostic assays: direct smear, histological examination, and molecular analysis for species identification. Epidemiological and demographic data were requested from each case and analyzed. Treatment and follow up of patient was also performed. RESULTS: Five cases were confirmed as Leishmania infection according to microscopic observation and molecular methods results. PCR-18S, PCR-N/RFLP and PCR-F/RFLP identified the following species: L. panamensis (2 cases), L. braziliensis (1 case), L.panamensis/L.guyanensis (1 case), L. mexicana complex (1 case). In treated patients, drugs were well tolerated, cure were documented and no relapse have been currently reported (3 years later). CONCLUSIONS: Clinical characteristics, demographic data, and epidemiological features of infection for each case evidence the potential risk related with travel to endemic areas of leishmaniasis. KEYWORKS: Cutaneous leishmaniasis, Epidemiology, Imported cases.

17.
Front Pharmacol ; 13: 894550, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35721217

RESUMEN

Introduction: Immune checkpoint inhibitor (ICI) therapy is markedly improving the prognosis of patients with several types of cancer. On the other hand, the growth in the use of these drugs in oncology is associated with an increase in multiple immune-related adverse events (irAEs), whose optimal prevention and management remain unclear. In this context, there is a need for reliable and validated biomarkers to predict the occurrence of irAEs in patients treated with ICIs. Thus, the main objective of this study is to evaluate the diagnostic performance of a sensitive routinely available panel of autoantibodies consisting of antinuclear antibodies, rheumatoid factor, and antineutrophil cytoplasmic antibodies to identify patients at risk of developing irAEs. Methods and Analysis: A multicenter, prospective, observational, cohort study has been designed to be conducted in patients diagnosed with cancer amenable to ICI therapy. Considering the percentage of ICI-induced irAEs to be 25% and a loss to follow-up of 5%, it has been estimated that a sample size of 294 patients is required to detect an expected sensitivity of the autoantibody panel under study of 0.90 with a confidence interval (95%) of no less than 0.75. For 48 weeks, patients will be monitored through the oncology outpatient clinics of five hospitals in Spain. Immune-related adverse events will be defined and categorized according to CTCAE v. 5.0. All the patients will undergo ordinary blood tests at specific moments predefined per protocol and extraordinary blood tests at the time of any irAE being detected. Ordinary and extraordinary samples will be frozen and stored in the biobank until analysis in the same autoimmunity laboratory when the whole cohort reaches week 48. A predictive model of irAEs will be constructed with potential risk factors of immune-related toxicity including the autoantibody panel under study. Ethics and Dissemination: This protocol was reviewed and approved by the Ethical Committee of the Basque Country and the Spanish Agency of Medicines and Medical Devices. Informed consent will be obtained from all participants before their enrollment. The authors declare that the results will be submitted to an international peer-reviewed journal for their prompt dissemination.

18.
Microorganisms ; 10(5)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35630499

RESUMEN

Xenobiotic contamination, a worldwide environmental concern, poses risks for humans, animals, microbe health, and agriculture. Hydrocarbons and heavy metals top the list of toxins that represent a risk to nature. This review deals with the study of Azospirillum sp., widely reported as plant growth-promoting bacteria in various cultures. However, its adaptation properties in adverse environments make it a good candidate for studying remediation processes in environments polluted with hydrocarbons and heavy metals. This review includes studies that address its properties as a plant growth promoter, its genomics, and that evaluate its potential use in the remediation of hydrocarbons and heavy metals.

19.
Inorg Chem ; 61(3): 1236-1248, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34990121

RESUMEN

Oxidative addition of 1.5 equiv of bromine or iodine to a Ir(I) sulfoxide pincer complex affords the corresponding Ir(IV) tris-bromido or tris-iodido complexes, respectively. The unprecedented trap-free reductive elimination of iodine from the Ir(IV)-iodido complex is induced by coordination of ligands or donor solvents. In the case of added I-, the isostructural tris-iodo Ir(III)-ate complex is quickly generated, which then can be readily reoxidized to the Ir(IV)-iodido complex with FcPF6 or electrochemically. DFT calculations indicate an "inverted ligand field" in the Ir(IV) complexes and favor dinuclear pathways for the reductive elimination of iodine from the formal d5 metal center.

20.
Physiother Theory Pract ; 38(1): 211-225, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32043406

RESUMEN

Background: Although the median frequency is used as a basis to assess the presence of muscular fatigue, some studies have found that it is not a good estimator for this purpose. Physiotherapists often deal with patients with movement issues related to fatigue. A new objective estimator that is easy to obtain and interpret can help with the management of such patients.Objective and Purpose: The aim of this study was to identify the frequency bands most affected by fatigue and propose a protocol to obtain such information.Methods: Thirty healthy subjects (age 22.05 ± 2.42 years, height 1.71 ± 0.08 m, and weight 68.75 ± 11.42 kg) were recruited to measure the rectus femoris electromyography (EMG) of both legs during gait, before and after a fatiguing protocol. Four frequency bands were studied: high frequency (107-250 Hz), midfrequency (65-94 Hz), 40 Hz (34-53 Hz), and low frequency (< 25 Hz). Each frequency band is related to different aspects of the muscular contraction.Results: The main finding is that the ratios of the 40-Hz frequency and low-frequency bands showed significant differences in both legs between pre-fatigue and post-fatigue recordings. Critical thresholds F* 4.86 and 4.93 were exceeded at 4.5-8.7%, 30.64-46%.38, 63.75-66.8%, and 83.69-90.79% and at 0-2.53%, 4.7-15.21%, 18.15-54.65%, and 55.81-99.95% of the gait cycle, respectively, with p values < .05.Conclusions: The low-frequency band constitutes the best indicator to assess fatigue in gait.


Asunto(s)
Fatiga Muscular , Músculo Cuádriceps , Adulto , Electromiografía , Marcha , Humanos , Contracción Muscular , Músculo Esquelético , Adulto Joven
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