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1.
J Food Sci Technol ; 59(8): 3201-3209, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35872725

RESUMEN

The sensory properties and appropriateness of cornelian cherry (Cornus mas L.) for processing is very closely related to its ripening stage, recognizable by firmness and skin colour to some extent. Due to the non-uniform ripening on the trees the quality of the fruits offered on the market depends very much on the harvest-method. Today, processors, who usually do not buy fresh fruits but frozen fruits or puree on the market, don`t have a suitable means for the accurate quality assessment of the raw material they need for the processing of high-quality products. The results of this work show for the first time that from the selected parameters (carbohydrates, organic acids, phenols) only flavonols, especially kaempferol-3-glucoside is appropriate to determine the stage of ripeness of cornelian cherries properly independent from species, provenance and crop year. Kaempferol 3-O-glucoside of about 1.75 mg/Kg in wild genotypes and of about 0.80 mg/Kg in most big cornelian cherry species can serve as a reference for sufficient ripeness and therefore for high fruit quality.

2.
Acta Neuropathol ; 139(5): 913-936, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31848709

RESUMEN

Atypical teratoid/rhabdoid tumors (ATRT) are known for their heterogeneity concerning pathophysiology and outcome. However, predictive factors within distinct subgroups still need to be uncovered. Using multiplex immunofluorescent staining and single-cell RNA sequencing we unraveled distinct compositions of the immunological tumor microenvironment (TME) across ATRT subgroups. CD68+ cells predominantly infiltrate ATRT-SHH and ATRT-MYC and are a negative prognostic factor for patients' survival. Within the murine ATRT-MYC and ATRT-SHH TME, Cd68+ macrophages are core to intercellular communication with tumor cells. In ATRT-MYC distinct tumor cell phenotypes express macrophage marker genes. These cells are involved in the acquisition of chemotherapy resistance in our relapse xenograft mouse model. In conclusion, the tumor cell-macrophage interaction contributes to ATRT-MYC heterogeneity and potentially to tumor recurrence.


Asunto(s)
Resistencia a Antineoplásicos/fisiología , Macrófagos/patología , Recurrencia Local de Neoplasia/patología , Microambiente Tumoral/fisiología , Animales , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias del Sistema Nervioso Central/metabolismo , Neoplasias del Sistema Nervioso Central/patología , Femenino , Humanos , Masculino , Ratones Transgénicos , Tumor Rabdoide/genética
3.
Anal Methods ; 16(24): 3859-3866, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38847307

RESUMEN

Methanol is a toxic alcohol contained in alcoholic beverages as a natural byproduct of fermentation or added intentionally to counterfeits to increase profit. To ensure consumer safety, many countries and the EU have established strict legislation limits for methanol content. Methanol concentration is mostly detected by laboratory instrumentation since mobile devices for routine on-site testing of beverages in distilleries, at border stations or even at home are not available. Here, we validated a handheld methanol detector for beverage analysis in an ISO 5725 interlaboratory trial: a total of 119 measurements were performed by 17 independent participants (distilleries, universities, authorities, and competence centers) from six countries on samples with relevant methanol concentrations (0.1, 1.5 vol%). The detector was based on a microporous separation filter and a nanostructured gas sensor allowing on-site measurement of methanol down to 0.01 vol% (in the liquid) within only 2 min by laymen. The detector showed excellent repeatability (<5.4%), reproducibility (<9.5%) and small bias (<0.012 vol%). Additional measurements on various methanol-spiked alcoholic beverages (whisky, rum, gin, vodka, tequila, port, sherry, liqueur) indicated that the detector is not interfered by environmental temperature and spirit composition, featuring excellent linearity (R2 > 0.99) down to methanol concentrations of 0.01 vol%. This device has been recently commercialized (Alivion Spark M-20) with comparable accuracy to the gold-standard gas chromatography and can be readily applied for final product inspection, intake control of raw materials or to identify toxic counterfeit products.


Asunto(s)
Bebidas Alcohólicas , Metanol , Metanol/análisis , Bebidas Alcohólicas/análisis , Reproducibilidad de los Resultados , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Laboratorios/normas
4.
Nat Commun ; 15(1): 8571, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39362842

RESUMEN

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a heterogeneous group of malignancies with poor outcome. Here, we identify a subgroup, PTCL-NOSSMARCB1-, which is characterized by the lack of the SMARCB1 protein and occurs more frequently in young patients. Human and murine PTCL-NOSSMARCB1- show similar DNA methylation profiles, with hypermethylation of T-cell-related genes and hypomethylation of genes involved in myeloid development. Single-cell analyses of human and murine tumors revealed a rich and complex network of interactions between tumor cells and an immunosuppressive and exhausted tumor microenvironment (TME). In a drug screen, we identified histone deacetylase inhibitors (HDACi) as a class of drugs effective against PTCL-NOSSmarcb1-. In vivo treatment of mouse tumors with SAHA, a pan-HDACi, triggered remodeling of the TME, promoting replenishment of lymphoid compartments and reversal of the exhaustion phenotype. These results provide a rationale for further exploration of HDACi combination therapies targeting PTCL-NOSSMARCB1- within the TME.


Asunto(s)
Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Inhibidores de Histona Desacetilasas , Linfoma de Células T Periférico , Proteína SMARCB1 , Microambiente Tumoral , Animales , Proteína SMARCB1/genética , Proteína SMARCB1/metabolismo , Humanos , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/tratamiento farmacológico , Linfoma de Células T Periférico/metabolismo , Linfoma de Células T Periférico/patología , Ratones , Inhibidores de Histona Desacetilasas/farmacología , Microambiente Tumoral/genética , Microambiente Tumoral/efectos de los fármacos , Femenino , Línea Celular Tumoral , Masculino , Vorinostat/farmacología , Análisis de la Célula Individual
5.
Biophys J ; 105(2): 463-72, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23870267

RESUMEN

An original method is presented to study single-colloid interaction with a substrate in liquid environment. Colloids, either in solution or adsorbed on a surface, are fixed by suction against the aperture of a microchanneled atomic force microscopy cantilever. Their adhesion to the substrate is measured, followed by their release via a short overpressure surge. Such colloid exchange procedure allows for 1), the quick variation of differently functionalized colloids within the same experiment; 2), the investigation of long-term interactions by leaving the colloids on a surface for a defined time before detaching them; and 3), the inspection of irreversible interactions. After validation of the method by reproducing literature results obtained with traditional colloidal atomic force microscopy, the serial use of colloids with different surface functionalization was shown on a micropatterned surface. Finally, concanavalin A-coated colloids were allowed to adsorb on human embryonic kidney cells and then detached one by one. The adhesion between cells and colloids was up to 60 nN, whereas individual cells adhered with 20 nN to the glass substrate. A cellular elastic modulus of 0.8 kPa was determined using the attached colloid as indenter.


Asunto(s)
Coloides/química , Adhesión Celular/efectos de los fármacos , Coloides/farmacología , Concanavalina A/química , Módulo de Elasticidad , Células HEK293 , Humanos , Microscopía de Fuerza Atómica
6.
Cells ; 11(8)2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35456033

RESUMEN

The murine esBAF complex plays a major role in the regulation of gene expression during stem cell development and differentiation. As one of its core subunits, Smarcb1 is indispensable for its function and its loss is connected to neurodevelopmental disorders and participates in the carcinogenesis of entities such as rhabdoid tumours. We explored how Smarcb1 regulates gene programs in murine embryonic stem cells (mESC) and in this way orchestrates differentiation. Our data underline the importance of Smarcb1 expression and function for the development of the nervous system along with basic cellular functions, such as cell adhesion and cell organisation. Using ChIP-seq, we were able to portray the consequences of Smarcb1 knockdown (kd) for the binding of esBAF and PRC2 as well as its influence on histone marks H3K27me3, H3K4me3 and H3K27ac. Their signals are changed in gene and enhancer regions of genes connected to nervous system development and offers a plausible explanation for changes in gene expression. Further, we describe a group of genes that are, despite increased BAF binding, suppressed after Smarcb1 kd by mechanisms independent of PRC2 function.


Asunto(s)
Tumor Rabdoide , Animales , Carcinogénesis , Diferenciación Celular/genética , Células Madre Embrionarias/metabolismo , Ratones , Tumor Rabdoide/genética , Tumor Rabdoide/metabolismo
7.
Nat Commun ; 13(1): 1544, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35318328

RESUMEN

Rhabdoid tumors (RT) are rare and highly aggressive pediatric neoplasms. Their epigenetically-driven intertumoral heterogeneity is well described; however, the cellular origin of RT remains an enigma. Here, we establish and characterize different genetically engineered mouse models driven under the control of distinct promoters and being active in early progenitor cell types with diverse embryonic onsets. From all models only Sox2-positive progenitor cells give rise to murine RT. Using single-cell analyses, we identify distinct cells of origin for the SHH and MYC subgroups of RT, rooting in early stages of embryogenesis. Intra- and extracranial MYC tumors harbor common genetic programs and potentially originate from fetal primordial germ cells (PGCs). Using PGC specific Smarcb1 knockout mouse models we validate that MYC RT originate from these progenitor cells. We uncover an epigenetic imbalance in MYC tumors compared to PGCs being sustained by epigenetically-driven subpopulations. Importantly, treatments with the DNA demethylating agent decitabine successfully impair tumor growth in vitro and in vivo. In summary, our work sheds light on the origin of RT and supports the clinical relevance of DNA methyltransferase inhibitors against this disease.


Asunto(s)
Tumor Rabdoide , Animales , Células Germinativas/patología , Humanos , Ratones , Tumor Rabdoide/genética , Tumor Rabdoide/patología , Proteína SMARCB1/genética , Análisis de la Célula Individual , Transcriptoma
8.
Neuro Oncol ; 23(4): 586-598, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-33175161

RESUMEN

BACKGROUND: Medulloblastoma (MB) is a malignant brain tumor in childhood. It comprises 4 subgroups with different clinical behaviors. The aim of this study was to characterize the transcriptomic landscape of MB, both at the level of individual tumors as well as in large patient cohorts. METHODS: We used a combination of single-cell transcriptomics, cell culture models and biophysical methods such as nanoparticle tracking analysis and electron microscopy to investigate intercellular communication in the MB tumor niche. RESULTS: Tumor cells of the sonic hedgehog (SHH)-MB subgroup show a differentiation blockade. These cells undergo extensive metabolic reprogramming. The gene expression profiles of individual tumor cells show a partial convergence with those of tumor-associated glial and immune cells. One possible cause is the transfer of extracellular vesicles (EVs) between cells in the tumor niche. We were able to detect EVs in co-culture models of MB tumor cells and oligodendrocytes. We also identified a gene expression signature, EVS, which shows overlap with the proteome profile of large oncosomes from prostate cancer cells. This signature is also present in MB patient samples. A high EVS expression is one common characteristic of tumors that occur in high-risk patients from different MB subgroups or subtypes. CONCLUSIONS: With EVS, our study uncovered a novel gene expression signature that has a high prognostic significance across MB subgroups.


Asunto(s)
Neoplasias Cerebelosas , Vesículas Extracelulares , Meduloblastoma , Neoplasias Cerebelosas/genética , Proteínas Hedgehog/genética , Humanos , Masculino , Meduloblastoma/genética , Transcriptoma
9.
Placenta ; 90: 128-137, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-32056544

RESUMEN

INTRODUCTION: The first lineage separation in mammalian development occurs when totipotent cells of the zygote give rise to the inner cell mass and the trophectoderm. The lineages are strictly separated by an epigenetic barrier. In vitro derivatives of these lineages embryonic stem cells (ESC) and trophoblast stem cells (TSC) are used to study the requirements needed to overcome the barrier in ESC to TSC conversion approaches. METHODS: Different combinations of TSC transcription factors were induced in ESC for three days. Cells were kept in TS medium with fetal bovine serum (FBS) or the chemically defined TX medium. Obtained cells were analysed for OCT4 levels, TSC surface marker levels, expression of TSC markers and methylation status of Elf5, Oct4 and Nanog promoters. Further, long-term culture stability and in vitro and in vivo differentiation was tested. RESULTS: Overexpression of Gata3, Eomes, Tfap2c, Ets2 and Cdx2 in ESC resulted in induction of TSC fate. Overexpression of Cdx2 or four factors (Gata3, Eomes, Tfap2c and Ets2) resulted in complete conversion only when cells were cultured in TX medium. The obtained induced TSC (iTSC) display characteristics of bona fide TSC in terms of marker expression and promoter methylation patterns. The generated converted cells were shown to display self-renewal and to be capable to differentiate into TSC derivatives in vitro and in vivo. CONCLUSION: Gata3, Eomes, Tfap2c, Ets2 and Cdx2 overexpression in ESC resulted in stable iTSC fate independent of culture conditions. For four factors or Cdx2 alone, TX medium is required for complete TSC conversion.


Asunto(s)
Técnicas de Cultivo de Célula , Diferenciación Celular/fisiología , Medios de Cultivo , Células Madre Embrionarias/citología , Trofoblastos/citología , Animales , Linaje de la Célula/fisiología , Ratones
10.
Front Cell Dev Biol ; 8: 559554, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33102470

RESUMEN

Heparan sulfate (HS) is a glycosaminoglycan found mainly in its protein-conjugated form at the cell surface and the extracellular matrix. Its high sulfation degree mediates functional interactions with positively charged amino acids in proteins. 2-O sulfation of iduronic acid and 3-O sulfation of glucosamine in HS are mediated by the sulfotransferases HS2ST and HS3ST, respectively, which are dysregulated in several cancers. Both sulfotransferases regulate breast cancer cell viability and invasion, but their role in cancer stem cells (CSCs) is unknown. Breast CSCs express characteristic markers such as CD44+/CD24-/low , CD133 and ALDH1 and are involved in tumor initiation, formation, and recurrence. We studied the influence of HS2ST1 and HS3ST2 overexpression on the CSC phenotype in breast cancer cell lines representative of the triple-negative (MDA-MB-231) and hormone-receptor positive subtype (MCF-7). The CD44+/CD24-/low phenotype was significantly reduced in MDA-MB-231 cells after overexpression of both enzymes, remaining unaltered in MCF-7 cells. ALDH1 activity was increased after HS2ST1 and HS3ST2 overexpression in MDA-MB-231 cells and reduced after HS2ST1 overexpression in MCF-7 cells. Colony and spheroid formation were increased after HS2ST1 and HS3ST2 overexpression in MCF-7 cells. Moreover, MDA-MB-231 cells overexpressing HS2ST1 formed more colonies and could not generate spheres. The phenotypic changes were associated with complex changes in the expression of the stemness-associated notch and Wnt-signaling pathways constituents, syndecans, heparanase and Sulf1. The results improve our understanding of breast CSC function and mark a subtype-specific impact of HS modifications on the CSC phenotype of triple-negative and hormone receptor positive breast cancer model cell lines.

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