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1.
J Cereb Blood Flow Metab ; : 271678X231217669, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017004

RESUMEN

Increased neurotrophic support, including insulin-like growth factor I (IGF-I), is an important aspect of the adaptive response to ischemic insult. However, recent findings indicate that the IGF-I receptor (IGF-IR) in neurons plays a detrimental role in the response to stroke. Thus, we investigated the role of astrocytic IGF-IR on ischemic insults using tamoxifen-regulated Cre deletion of IGF-IR in glial fibrillary acidic protein (GFAP) astrocytes, a major cellular component in the response to injury. Ablation of IGF-IR in astrocytes (GFAP-IGF-IR KO mice) resulted in larger ischemic lesions, greater blood-brain-barrier disruption and more deteriorated sensorimotor coordination. RNAseq detected increases in inflammatory, cell adhesion and angiogenic pathways, while the expression of various classical biomarkers of response to ischemic lesion were significantly increased at the lesion site compared to control littermates. While serum IGF-I levels after injury were decreased in both control and GFAP-IR KO mice, brain IGF-I mRNA expression show larger increases in the latter. Further, greater damage was also accompanied by altered glial reactivity as reflected by changes in the morphology of GFAP astrocytes, and relative abundance of ionized calcium binding adaptor molecule 1 (Iba 1) microglia. These results suggest a protective role for astrocytic IGF-IR in the response to ischemic injury.

2.
Nat Commun ; 14(1): 5208, 2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37626123

RESUMEN

Aberrant enhancer activation is a key mechanism driving oncogene expression in many cancers. While much is known about the regulation of larger chromosome domains in eukaryotes, the details of enhancer-promoter interactions remain poorly understood. Recent work suggests co-activators like BRD4 and Mediator have little impact on enhancer-promoter interactions. In leukemias controlled by the MLL-AF4 fusion protein, we use the ultra-high resolution technique Micro-Capture-C (MCC) to show that MLL-AF4 binding promotes broad, high-density regions of enhancer-promoter interactions at a subset of key targets. These enhancers are enriched for transcription elongation factors like PAF1C and FACT, and the loss of these factors abolishes enhancer-promoter contact. This work not only provides an additional model for how MLL-AF4 is able to drive high levels of transcription at key genes in leukemia but also suggests a more general model linking enhancer-promoter crosstalk and transcription elongation.


Asunto(s)
Leucemia , Proteínas Nucleares , Humanos , Proteínas Nucleares/genética , Factores de Transcripción/genética , Secuencias Reguladoras de Ácidos Nucleicos , Leucemia/genética , Regiones Promotoras Genéticas/genética , Proteínas de Ciclo Celular , Proteínas de Fusión Oncogénica/genética , Proteína de la Leucemia Mieloide-Linfoide/genética
3.
Clin Cancer Res ; 29(17): 3352-3361, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37058595

RESUMEN

PURPOSE: In the phase III CheckMate 238 study, adjuvant nivolumab significantly improved recurrence-free survival (RFS) and distant metastasis-free survival versus ipilimumab in patients with resected stage IIIB-C or stage IV melanoma, with benefit sustained at 4 years. We report updated 5-year efficacy and biomarker findings. PATIENTS AND METHODS: Patients with resected stage IIIB-C/IV melanoma were stratified by stage and baseline programmed death cell ligand 1 (PD-L1) expression and received nivolumab 3 mg/kg every 2 weeks or ipilimumab 10 mg/kg every 3 weeks for four doses and then every 12 weeks, both intravenously for 1 year until disease recurrence, unacceptable toxicity, or withdrawal of consent. The primary endpoint was RFS. RESULTS: At a minimum follow-up of 62 months, RFS with nivolumab remained superior to ipilimumab (HR = 0.72; 95% confidence interval, 0.60-0.86; 5-year rates of 50% vs. 39%). Five-year distant metastasis-free survival (DMFS) rates were 58% with nivolumab versus 51% with ipilimumab. Five-year overall survival (OS) rates were 76% with nivolumab and 72% with ipilimumab (75% data maturity: 228 of 302 planned events). Higher levels of tumor mutational burden (TMB), tumor PD-L1, intratumoral CD8+ T cells and IFNγ-associated gene expression signature, and lower levels of peripheral serum C-reactive protein were associated with improved RFS and OS with both nivolumab and ipilimumab, albeit with limited clinically meaningful predictive value. CONCLUSIONS: Nivolumab is a proven adjuvant treatment for resected melanoma at high risk of recurrence, with sustained, long-term improvement in RFS and DMFS compared with ipilimumab and high OS rates. Identification of additional biomarkers is needed to better predict treatment outcome. See related commentary by Augustin and Luke, p. 3253.


Asunto(s)
Melanoma , Nivolumab , Humanos , Nivolumab/administración & dosificación , Ipilimumab/uso terapéutico , Antígeno B7-H1 , Receptor de Muerte Celular Programada 1/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/patología , Adyuvantes Inmunológicos/uso terapéutico , Biomarcadores , Melanoma Cutáneo Maligno
4.
Rev. chil. obstet. ginecol. (En línea) ; 87(6): 388-395, dic. 2022. tab
Artículo en Inglés | LILACS | ID: biblio-1423749

RESUMEN

Objective: Determining the appropriate approach for delivery after previous cesarean is a very controversial issue. Our objective was to establish whether pregnant women with a previous cesarean have an increased maternal and fetal morbidity and mortality after attempting vaginal delivery as well as to determine which factors may influence the achievement of a vaginal birth after cesarean. Materials and methods: A retrospective observational cohort study including 390 patients (196 cesarean group and 194 nulliparous group) was carried out. We compared neonatal and maternal outcomes between groups. Afterward, a multivariate logistic regression was applied for our second objective. Results: There were higher rates of uterine rupture (2% vs. 0%, p: 0.045) and puerperal hemorrhage (9.7% vs. 3.1%, p: 0.008) in the cesarean group and lower vaginal delivery rate (58.2% vs. 77.8%, p < 0.0005). We found that the induced onset of labor (OR = 2.9) and new born weight (OR = 1.0001) were associated with an increased risk of cesarean section. Conclusions: Our findings stress the need for further investigations in this field, which might provide a basis for a better management of patients with a previous cesarean.


Objetivo: Determinar el abordaje adecuado del tipo de parto tras una cesárea previa es un tema muy controvertido. Nuestro objetivo fue establecer si las gestantes con cesárea previa presentan mayor morbimortalidad materna y fetal tras intentar parto vaginal, así como determinar qué factores pueden influir en conseguir un parto vaginal posterior a la cesárea. Material y métodos: Estudio observacional de cohortes retrospectivo incluyendo 390 pacientes (196 con cesárea previa, 194 nulíparas). Comparamos los datos sobre los resultados neonatales y maternos. Posteriormente se aplicó un modelo de regresión logística multivariante. Resultados: Hubo mayores tasas de ruptura uterina (2% vs. 0%; p = 0.045) y hemorragia puerperal (9.7% vs. 3.1%, p: 0.008) en el grupo de cesárea anterior, así como una tasa de parto vaginal mas baja (58.2% vs. 77.8%, p < 0.0005). La inducción del parto (OR = 2,9) y el peso del recién nacido (OR = 1.0001) se asociaron a un mayor riesgo de cesárea. Conclusión: La probabilidad de parto vaginal en estas pacientes disminuye cuanto mayor sea el peso del recién nacido y con partos inducidos.


Asunto(s)
Humanos , Femenino , Embarazo , Parto Vaginal Después de Cesárea/efectos adversos , Rotura Uterina/epidemiología , Mortalidad Infantil , Mortalidad Materna , Análisis Multivariante , Análisis de Regresión , Estudios Retrospectivos , Hemorragia Posparto/epidemiología
5.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36077560

RESUMEN

A series of poly(2-hydroxyethyl methacrylate) (PHEMA) thin films entrapping photosensitizer Rose Bengal (RB) and tetrabutylammonium iodide (TBAI) have been synthetized. The materials have been characterized by means of Thermogravimetric Analysis (TGA), Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and UV-vis Absorption spectroscopy. Irradiation of the materials with white light led to the generation of several bactericidal species, including singlet oxygen (1O2), triiodide anion (I3-) and hydrogen peroxide (H2O2). 1O2 production was demonstrated spectroscopically by reaction with the chemical trap 2,2'-(anthracene-9,10-diylbis(methylene))dimalonic acid (ABDA). In addition, the reaction of iodide anion with 1O2 yielded I3- inside the polymeric matrix. This reaction is accompanied by the formation of H2O2, which diffuses out the polymeric matrix. Generation of both I3- and H2O2 was demonstrated spectroscopically (directly in the case of triiodide by the absorption at 360 nm and indirectly for H2O2 using the xylenol orange test). A series of photodynamic inactivation assays were conducted with the synthesized polymers against Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa. Complete eradication (7 log10 CFU/mL) of both bacteria occurred after only 5 min of white light irradiation (400-700 nm; total energy dose 24 J/cm2) of the polymer containing both RB and TBAI. The control polymer without embedded iodide (only RB) showed only marginal reductions of ca. 0.5 log10 CFU/mL. The main novelty of the present investigation is the generation of three bactericidal species (1O2, I3- and H2O2) at the same time using a single polymeric material containing all the elements needed to produce such a bactericidal cocktail, although the most relevant antimicrobial activity is shown by H2O2. This experimental approach avoids multistep protocols involving a final step of addition of I-, as described previously for other assays in solution.


Asunto(s)
Peróxido de Hidrógeno , Rosa Bengala , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli , Peróxido de Hidrógeno/farmacología , Yoduros , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Polímeros , Rosa Bengala/farmacología
7.
Proc Natl Acad Sci U S A ; 119(29): e2204527119, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858325

RESUMEN

Mice with insulin receptor (IR)-deficient astrocytes (GFAP-IR knockout [KO] mice) show blunted responses to insulin and reduced brain glucose uptake, whereas IR-deficient astrocytes show disturbed mitochondrial responses to glucose. While exploring the functional impact of disturbed mitochondrial function in astrocytes, we observed that GFAP-IR KO mice show uncoupling of brain blood flow with glucose uptake. Since IR-deficient astrocytes show higher levels of reactive oxidant species (ROS), this leads to stimulation of hypoxia-inducible factor-1α and, consequently, of the vascular endothelial growth factor angiogenic pathway. Indeed, GFAP-IR KO mice show disturbed brain vascularity and blood flow that is normalized by treatment with the antioxidant N-acetylcysteine (NAC). NAC ameliorated high ROS levels, normalized angiogenic signaling and mitochondrial function in IR-deficient astrocytes, and normalized neurovascular coupling in GFAP-IR KO mice. Our results indicate that by modulating glucose uptake and angiogenesis, insulin receptors in astrocytes participate in neurovascular coupling.


Asunto(s)
Astrocitos , Encéfalo , Insulina , Neovascularización Fisiológica , Acoplamiento Neurovascular , Animales , Astrocitos/metabolismo , Encéfalo/irrigación sanguínea , Proteína Ácida Fibrilar de la Glía/genética , Glucosa/metabolismo , Insulina/metabolismo , Ratones , Ratones Noqueados , Especies Reactivas de Oxígeno/metabolismo , Receptor de Insulina/genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
8.
Cancers (Basel) ; 14(10)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35626131

RESUMEN

Malignant pleural effusion (MPE) is a common severe complication of advanced lung adenocarcinoma (LAC). Neutrophils, an essential component of tumor infiltrates, contribute to tumor progression and their counts in MPE have been associated with worse outcome in LAC. This study aimed to evaluate phenotypical and functional changes of neutrophils induced by MPE to determine the influence of MPE immunomodulatory factors in neutrophil response and to find a possible association between neutrophil functions and clinical outcomes. Pleural fluid samples were collected from 47 LAC and 25 heart failure (HF) patients. We measured neutrophil degranulation products by ELISA, oxidative burst capacity and apoptosis by flow cytometry, and NETosis by fluorescence. The concentration of degranulation products was higher in MPE-LAC than in PE-HF. Functionally, neutrophils cultured with MPE-LAC had enhanced survival and neutrophil extracellular trap (NET) formation but had reduced oxidative burst capacity. In MPE, NETosis was positively associated with MMP-9, P-selectin, and sPD-L1 and clinically related to a worse outcome. This is the first study associating NETs with a worse outcome in MPE. Neutrophils likely contribute to tumor progression through the release of NETs, suggesting that they are a potential therapeutic target in LAC.

10.
J Chromatogr A ; 1663: 462768, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-34974368

RESUMEN

New psychoactive substances (NPS) continue to emerge in the drug market every year, becoming a global threat to public health and safety. These compounds are mostly synthetic cannabinoids and designer cathinones. However, synthetic opioids have appeared on the recreational drug markets in recent years, particularly fentanyl and its derivatives ("fentanyls"). Fentanyl and its analogs are related to harmful intoxications and an increase in opioid-related mortality in many countries, such as in the United States and Europe in the last years. Taking the drug related global crisis into consideration, this work developed and validated an effective and sensitive method based on fabric phase sorptive extraction (FPSE) followed by gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of 11 fentanyl analogs in oral fluid samples. The extraction was carried out using a sol-gel Carbowax 20 M sorbent immobilized on 100% cellulose fabric substrate and using ethyl acetate as the desorption solvent. The limits of detection (LODs) and quantification (LOQs) ranged from 1 to 15 ng mL-1 and 5 to 50 ng mL-1, respectively. Intra-day and inter-day precision were found within 8.2% and 8.6%, respectively, while accuracy ranged from -5.5 to 9.1%, in accordance with the established criteria. The absolute recovery values were in the range of 94.5%-109.1%. The validated method demonstrated its great potential to detect and quantify fentanyl analogs in possible forensic work and off-site analysis in road traffic cases.


Asunto(s)
Analgésicos Opioides , Drogas Ilícitas , Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Textiles
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