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1.
Science ; 367(6475): 246-247, 2020 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-31949066
2.
Cell Physiol Biochem ; 53(6): 921-932, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31778305

RESUMEN

BACKGROUND/AIMS: Lysophosphatidic acid (LPA) is a phospholipid signal molecule that regulates many cellular processes both physiological and pathological. Moreover, its high plasma concentrations are toxic for several cellular types, including erythrocytes (RBC), as it acts as a pro-thrombotic and pro-atherogenic agent. It is therefore essential to explore the potential protective role of nutrition in protecting cells from the possible toxic effects of high plasma concentrations of LPA by testing bioactive nutrients. In particular, our focus was on hydroxytyrosol (HT), a phenolic antioxidant occurring naturally in virgin olive oil, investigating its possible protective effect in preventing LPA-induced programmed cell death (eryptosis) in human RBC. METHODS: Intact RBC were incubated in the presence of 2.5 µM LPA and increasing concentrations of HT. Phosphatidylserine (PS) exposure with cell shrinkage, influx of extracellular calcium (Ca2+), adenosine triphosphate (ATP) and glutathione levels were measured by FACS analysis. In addition, confocal laser scanning microscopy was used to determine RBC morphological alterations, as well as microvesicle formation. RESULTS: Our study confirms that LPA-induced eryptosis is characterized by PS exposure at the cell surface, with cell shrinkage and ATP and glutathione depletion; (Ca2+) influx is also a key event that triggers eryptosis. Here we report for the first time that cell co-incubation with LPA and in quantities as low as 0.1 µM HT causes a significant decrease in PS-exposing RBC, in addition to providing significant protection from the decrease in cell volume. Moreover, treatment of RBC with HT counters the influx of extracellular Ca2+ and completely restores ATP and glutathione content at 1 µM. Finally, under the same experimental conditions, HT exerts a protective effect on RBC morphological changes and microvescicle release, completely restoring the typical biconcave shape at 1 µM. CONCLUSION: Taken together, the findings reported in this paper point to a novel biological effect for HT in preventing programmed suicidal death in anucleated cells and indicate that prevention from LPA toxic effects may represent an additional mechanism responsible for the health-promoting effect of this dietary phenol which has been claimed, particularly related to cardiovascular diseases.


Asunto(s)
Eriptosis/efectos de los fármacos , Lisofosfolípidos/toxicidad , Alcohol Feniletílico/análogos & derivados , Fosfatidilserinas/farmacología , Adenosina Trifosfato/metabolismo , Calcio/metabolismo , Tamaño de la Célula/efectos de los fármacos , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Glutatión/metabolismo , Humanos , Alcohol Feniletílico/farmacología , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo
3.
Invest Ophthalmol Vis Sci ; 60(14): 4583-4595, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31675075

RESUMEN

Purpose: Trabecular meshwork (TM) cells detect and coordinate responses to intraocular pressure (IOP) in the eye. TM cells become dysfunctional in glaucoma where IOP is often elevated. Recently, we showed that normal TM (NTM) cells communicate by forming tubular connections called tunneling nanotubes (TNTs). Here, we investigated TNTs in glaucomatous TM (GTM) cells. Methods: Primary GTM and NTM cells were established from cadaver eyes. Transfer of Vybrant DiO and DiD-labeled vesicles via TNT connections was measured. Imaris software measured the number and length of cell protrusions from immunofluorescent confocal images. Live-cell imaging of the actin cytoskeleton was performed. The distribution of myosin-X, a regulator of TNTs/filopodia, was investigated in TM cells and tissue. Results: GTM cells contained significantly more transferred fluorescent vesicles than NTM cells (49.6% vs. 35%). Although NTM cells had more protrusions at the cell surface than GTM cells (7.61 vs. 4.65 protrusions/cell), GTM protrusions were significantly longer (12.1 µm vs. 9.76 µm). Live-cell imaging demonstrated that the GTM actin cytoskeleton was less dynamic, and vesicle transfer between cells was significantly slower than NTM cells. Furthermore, rearrangement of the actin cortex adjacent to the TNT may influence TNT formation. Myosin-X immunostaining was punctate and disorganized in GTM cells and tissue compared to age-matched NTM controls. Conclusions: Together, our data demonstrate that GTM cells have phenotypic and functional differences in their TNTs. Significantly slower vesicle transfer via TNTs in GTM cells may delay the timely propagation of cellular signals when pressures become elevated in glaucoma.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Glaucoma de Ángulo Abierto/patología , Miosinas/metabolismo , Nanotubos , Seudópodos/metabolismo , Malla Trabecular/patología , Western Blotting , Tamaño de la Célula , Células Cultivadas , Senescencia Celular/fisiología , Densitometría , Glaucoma de Ángulo Abierto/metabolismo , Humanos , Microscopía Confocal , Fagocitosis/fisiología , Fenotipo , Transducción de Señal/fisiología , Malla Trabecular/metabolismo
4.
Cell Physiol Biochem ; 53(4): 638-647, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31556253

RESUMEN

BACKGROUND/AIMS: Prolonged hyperosmotic shrinkage evokes expression of osmoprotective genes via nuclear factor NFAT5-mediated pathway and activates Na+ influx via hypertonicity-induced cation channels (HICC). In human umbilical vein endothelial cells (HUVEC) elevation of intracellular sodium concentration ([Na+]i) triggers transcription of dozens of early response genes (ERG). This study examined the role of monovalent cations in the expression of Na+i-sensitive ERGs in iso- and hyperosmotically shrunken HUVEC. METHODS: Cell volume was measured by 3D reconstruction of cell shape and as 14C-urea available space. Intracellular Na+ and K+ content was measured by flame atomic absorption spectrometry. ERG transcription was estimated by RT-PCR. RESULTS: Elevation of medium osmolality by 150 mM mannitol or cell transfer from hypo- to isosmotic medium decreased cell volume by 40-50%. Hyperosmotic medium increased [Na+]i by 2-fold whereas isosmotic shrinkage had no impact on this parameter. Hyperosmotic but not isosmotic shrinkage increased up-to 5-fold the content of EGR1, FOS, ATF3, ZFP36 and JUN mRNAs. Expression of these ERGs triggered by hyperosmotic shrinkage and Na+,K+-ATPase inhibition by 0.1 µM ouabain exhibited positive correlation (R2=0.9383, p=0.0005). Isosmotic substitution of NaCl by N-methyl-D-glucamine abolished an increment of [Na+]i and ERG expression triggered by mannitol addition. CONCLUSION: Augmented expression of ERGs in hyperosmotically shrunken HUVEC is mediated by elevation of [Na+]i.


Asunto(s)
Tamaño de la Célula , Sodio/metabolismo , Tamaño de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Meglumina/farmacología , Ouabaína/farmacología , Potasio/metabolismo , Cloruro de Sodio/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo
5.
Nat Commun ; 10(1): 4113, 2019 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-31511517

RESUMEN

Intra-organ communication guides morphogenetic processes that are essential for an organ to carry out complex physiological functions. In the heart, the growth of the myocardium is tightly coupled to that of the endocardium, a specialized endothelial tissue that lines its interior. Several molecular pathways have been implicated in the communication between these tissues including secreted factors, components of the extracellular matrix, or proteins involved in cell-cell communication. Yet, it is unknown how the growth of the endocardium is coordinated with that of the myocardium. Here, we show that an increased expansion of the myocardial atrial chamber volume generates higher junctional forces within endocardial cells. This leads to biomechanical signaling involving VE-cadherin, triggering nuclear localization of the Hippo pathway transcriptional regulator Yap1 and endocardial proliferation. Our work suggests that the growth of the endocardium results from myocardial chamber volume expansion and ends when the tension on the tissue is relaxed.


Asunto(s)
Endocardio/crecimiento & desarrollo , Miocardio/metabolismo , Transducción de Señal , Pez Cebra/embriología , Animales , Antígenos CD/metabolismo , Fenómenos Biomecánicos , Cadherinas/metabolismo , Núcleo Celular/metabolismo , Proliferación Celular , Tamaño de la Célula , Proteínas del Citoesqueleto/metabolismo , Endocardio/citología , Atrios Cardíacos/citología , Atrios Cardíacos/metabolismo , Proteína Homeótica Nkx-2.5/metabolismo , Uniones Intercelulares/metabolismo , Modelos Biológicos , Mutación/genética , Transactivadores/metabolismo , Proteínas Wnt/metabolismo , Proteínas de Pez Cebra/metabolismo
6.
Muscle Nerve ; 60(6): 801-810, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31531861

RESUMEN

INTRODUCTION: Improved methods are needed to detect and quantify age-related muscle change. In this study we assessed the electrical properties of muscle impacted by acquired mitochondrial DNA mutations via the PolG mouse, which exhibits typical age-associated features, and the impact of a potential therapy, nicotinamide mononucleotide (NMN). METHODS: The gastrocnemii of 24 PolG and 30 wild-type (WT) mice (8 PolG and 17 WT treated with NMN) were studied in an electrical impedance-measuring cell. Conductivity and relative permittivity were determined from the impedance data. Myofiber cross-sectional area (CSA) was quantified histologically. RESULTS: Untreated PolG mice demonstrated alterations in several impedance features, including 50-kHz relative permittivity and center frequency. A potential effect of NMN was also observed in these parameters in PolG but not WT animals. Impedance values correlated with myofiber CSA. DISCUSSION: Electrical impedance is sensitive to myofiber features considered characteristic of aging and to the impact of a potential therapy.


Asunto(s)
Envejecimiento Prematuro/fisiopatología , Fibras Musculares Esqueléticas/patología , Músculo Esquelético/fisiopatología , Envejecimiento Prematuro/patología , Animales , Tamaño de la Célula , Polimerasa del ADN Mitocondrial/genética , ADN Mitocondrial/genética , Modelos Animales de Enfermedad , Impedancia Eléctrica , Técnicas de Sustitución del Gen , Ratones , Fibras Musculares Esqueléticas/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/patología , Mutación , Miografía/métodos , Mononucleótido de Nicotinamida/farmacología
7.
BMC Bioinformatics ; 20(1): 448, 2019 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-31477013

RESUMEN

BACKGROUND: Multiplexed in-situ fluorescent imaging offers several advantages over single-cell assays that do not preserve the spatial characteristics of biological samples. This spatial information, in addition to morphological properties and extensive intracellular or surface marker profiling, comprise promising avenues for rapid advancements in the understanding of disease progression and diagnosis. As protocols for conducting such imaging experiments continue to improve, it is the intent of this study to provide and validate software for processing the large quantity of associated data in kind. RESULTS: Cytokit offers (i) an end-to-end, GPU-accelerated image processing pipeline; (ii) efficient input/output (I/O) strategies for operations specific to high dimensional microscopy; and (iii) an interactive user interface for cross filtering of spatial, graphical, expression, and morphological cell properties within the 100+ GB image datasets common to multiplexed immunofluorescence. Image processing operations supported in Cytokit are generally sourced from existing deep learning models or are at least in part adapted from open source packages to run in a single or multi-GPU environment. The efficacy of these operations is demonstrated through several imaging experiments that pair Cytokit results with those from an independent but comparable assay. A further validation also demonstrates that previously published results can be reproduced from a publicly available multiplexed image dataset. CONCLUSION: Cytokit is a collection of open source tools for quantifying and analyzing properties of individual cells in large fluorescent microscopy datasets that are often, but not necessarily, generated from multiplexed antibody labeling protocols over many fields of view or time periods. This project is best suited to bioinformaticians or other technical users that wish to analyze such data in a batch-oriented, high-throughput setting. All source code, documentation, and data generated for this article are available under the Apache License 2.0 at https://github.com/hammerlab/cytokit .


Asunto(s)
Biomarcadores/metabolismo , Procesamiento de Imagen Asistida por Computador/métodos , Microscopía Fluorescente/métodos , Análisis de la Célula Individual/métodos , Programas Informáticos , Linfocitos T/metabolismo , Tamaño de la Célula , Células Cultivadas , Humanos , Linfocitos T/citología
8.
J Chem Phys ; 151(8): 085101, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31470695

RESUMEN

Periodic molecular dynamics simulations of proteins may suffer from image interactions. Similarly, the hydrophobic effect required to keep a protein folded may not be enforced by small simulation cells. Accordingly, errors may arise both from the water concentration per se and the image interactions. Intrinsically disordered proteins are particularly sensitive, providing a worst-case estimate of the errors. Following this reasoning, we studied Aß40 (Aß), a disordered peptide central to Alzheimer's disease, by 100 different simulations with variable cell size from very large (20 Å) to very small (3 Å). Even for this very disordered peptide, most properties are not cell-size dependent, justifying the common use of modest-sized (10 Å) cells for simulating proteins. The radius of gyration, secondary structure, intrapeptide, and peptide-water hydrogen bonds are similar relative to standard deviations at any cell size. However, hydrophobic surface area increases significantly in small cells (confidence 95%, two-tailed t-test), as does the standard deviation in exposure and backbone conformations (>40% and >27%). Similar results were obtained for the force fields OPLS3e, Ambersb99-ILDN, and Charmm22*. The similar prevalence of structures and α-ß transitions in long and short simulations indicate small diffusion barriers, which we suggest is a defining hallmark of intrinsically disordered proteins. Whereas hydrophilic exposure dominates in large cells, hydrophobic exposure dominates in small cells, suggesting a weakening of the hydrophobic effect by image interactions and the few water layers available to keep the protein compact, with a critical limit of 2-3 water layers required to enforce the hydrophobic effect.


Asunto(s)
Péptidos beta-Amiloides/química , Tamaño de la Célula , Proteínas Intrínsecamente Desordenadas/química , Simulación de Dinámica Molecular , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Conformación Proteica
9.
Mol Cell Biochem ; 461(1-2): 195-204, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31414336

RESUMEN

Recent studies on mice with null mutation of the angiotensin type 2 receptor (AT2R) gene have implicated the involvement of AT2R in regulating adipocyte size and obesity, a major risk factor for metabolic syndrome. However, the outcome from these studies remains inconclusive. Therefore, current study was designed to test whether pharmacological activation of AT2R regulates adiposity and lipid metabolism. Male mice (5-weeks old) were pre-treated with vehicle or AT2R agonist (C21, 0.3 mg/kg, i.p., daily, for 4 days) and fed normal diet (ND). Then these animals were subdivided into ND and high-fat diet (HFD) regimen and concomitantly treated with vehicle or C21 through day 14. Vehicle-treated HFD-fed mice demonstrated an increase in epididymal white adipose tissue (eWAT) weight and adipocyte size, which were associated with increased eWAT expression of the lipogenic regulators, fatty acid binding protein and fatty acid synthase, decreased expression of adipose triglyceride lipase and increased expression of hormone-sensitive lipase. Interestingly, C21 pre-treatment altered HFD-induced changes in lipogenic and lipolytic regulators. C21 pre-treatment prevented decrease in expression of uncoupler protein-1 in brown adipose in HFD-fed mice, which was associated with increased core temperature. In addition, C21 pre-treatment ameliorated plasma-free fatty acids, triglycerides, insulin and tumor necrosis factor-α in HFD-fed mice. Ex-vivo study in isolated primary epididymal adipocytes revealed that C21 inhibits long chain fatty acid transporter, via a nitric oxide synthase/guanylate cyclase/protein kinase G-dependent pathway. Collectively, we propose pharmacological activation of AT2R regulates fatty acid metabolism and thermogenesis and prevents HFD-induced adiposity in mice.


Asunto(s)
Adiposidad , Metabolismo de los Lípidos , Receptor de Angiotensina Tipo 2/metabolismo , Adipocitos/citología , Adipocitos/metabolismo , Adiponectina/sangre , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Temperatura Corporal , Peso Corporal , Tamaño de la Célula , Ingestión de Energía , Epidídimo/anatomía & histología , Ácidos Grasos/sangre , Insulina/sangre , Masculino , Ratones Endogámicos C57BL , Triglicéridos/sangre , Factor de Necrosis Tumoral alfa/sangre , Proteína Desacopladora 1/metabolismo
10.
J Biotechnol ; 304: 16-27, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31394111

RESUMEN

Computational fluid dynamics (CFD) modeling can be applied to understand hydrodynamics in stirred suspension bioreactors, which can in turn affect cell viability, proliferation, pluripotency and differentiation. In this study, we developed a CFD model to determine the effects of average shear rates and turbulent eddies on the formation and growth of murine embryonic stem cell aggregates. We found a correlation between average eddy size and aggregate size, which depended on bioreactor agitation rates. By relating these computational and biological variables, CFD modeling can predict optimal agitation rates to grow embryonic stem cell aggregates in stirred suspension bioreactors. To examine the effect of hydrodynamics on pluripotency, mESCs cultured in bioreactors under various agitation rates were tested for SSEA-1, Sox-2, and Nanog expression. Cells maintained a minimum of 95% positive expression with no change in the intensity distribution pattern between the different bioreactor conditions. This indicates that the average level of pluripotency marker expression is independent of changes in the hydrodynamic profile and resulting aggregate size distribution. The findings here can be further extended to other cell types that grow as aggregates in stirred suspension bioreactors and offer important insights necessary to realize cell therapies.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Células Madre Embrionarias/citología , Células Madre Pluripotentes/citología , Animales , Reactores Biológicos , Agregación Celular , Tamaño de la Célula , Células Cultivadas , Hidrodinámica , Ratones , Modelos Teóricos , Estrés Mecánico
11.
Int J Mol Sci ; 20(17)2019 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-31450555

RESUMEN

ZO-2 is a cytoplasmic protein of tight junctions (TJs). Here, we describe ZO-2 involvement in the formation of the apical junctional complex during early development and in TJ biogenesis in epithelial cultured cells. ZO-2 acts as a scaffold for the polymerization of claudins at TJs and plays a unique role in the blood-testis barrier, as well as at TJs of the human liver and the inner ear. ZO-2 movement between the cytoplasm and nucleus is regulated by nuclear localization and exportation signals and post-translation modifications, while ZO-2 arrival at the cell border is triggered by activation of calcium sensing receptors and corresponding downstream signaling. Depending on its location, ZO-2 associates with junctional proteins and the actomyosin cytoskeleton or a variety of nuclear proteins, playing a role as a transcriptional repressor that leads to inhibition of cell proliferation and transformation. ZO-2 regulates cell architecture through modulation of Rho proteins and its absence induces hypertrophy due to inactivation of the Hippo pathway and activation of mTOR and S6K. The interaction of ZO-2 with viral oncoproteins and kinases and its silencing in diverse carcinomas reinforce the view of ZO-2 as a tumor regulator protein.


Asunto(s)
Regulación de la Expresión Génica , Transducción de Señal , Proteína de la Zonula Occludens-2/genética , Proteína de la Zonula Occludens-2/metabolismo , Actomiosina/metabolismo , Animales , Apoptosis/genética , Proliferación Celular , Forma de la Célula , Tamaño de la Célula , Desarrollo Embrionario/genética , Humanos , Proteínas Nucleares/metabolismo , Especificidad de Órganos/genética , Unión Proteica , Transporte de Proteínas , Uniones Estrechas/metabolismo , Transcripción Genética , Proteína de la Zonula Occludens-2/química
12.
Eur J Pharmacol ; 860: 172554, 2019 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-31326378

RESUMEN

Cancer treatment is one of the major fields of interest for the scientific community. Investment in cancer research is costly but essential to provide patients with more effective and safe treatments. In this project, we describe the synthesis and characterization of new thiazole derivatives coupled to CPP2, a cell-penetrating peptide (CPP) reported for colon cancer cells. Using a human adenocarcinoma-derived cell line (Caco-2), these new CPPs were evaluated for antiproliferative (3H-thymidine incorporation) and cytotoxic effect (extracellular lactate dehydrogenase activity). One of these derivatives, the BTZCA thiazole compound and its peptide-conjugated (BTZCA-CPP2) also showed the ability to decrease tumour cell viability and proliferation, with potential cytotoxic effect against human breast cancer MCF-7 cells. Then, cytotoxicity studies were developed against J774, L929 and THP1 cell lines and this new family showed no significant cytotoxicity, when compared to their counterparts alone (BTZCA and CPP2). The use of smaller CPP conjugated with this family of derivatives can be also considered in future for the development of new drugs to cancer therapy.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Péptidos de Penetración Celular/química , Péptidos de Penetración Celular/farmacología , Secuencia de Aminoácidos , Línea Celular Tumoral , Tamaño de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Tiazoles/química
13.
Phys Rev E ; 99(6-1): 062401, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31330615

RESUMEN

Mechanical strain and stress play a major role in biological processes such as wound healing or morphogenesis. To assess this role quantitatively, fixed or live images of tissues are acquired at a cellular precision in large fields of views. To exploit these data, large numbers of cells have to be analyzed to extract cell shape anisotropy and cell size. Most frequently, this is performed through detailed individual cell contour determination, using so-called segmentation computer programs, complemented if necessary by manual detection and error corrections. However, a coarse-grained and faster technique can be recommended in at least three situations: first, when detailed information on individual cell contours is not required; for instance, in studies which require only coarse-grained average information on cell anisotropy. Second, as an exploratory step to determine whether full segmentation can be potentially useful. Third, when segmentation is too difficult, for instance due to poor image quality or too large a cell number. We developed a user-friendly, Fourier-transform-based image analysis pipeline. It is fast (typically 10^{4} cells per minute with a current laptop computer) and suitable for time, space, or ensemble averages. We validate it on one set of artificial images and on two sets of fully segmented images, one from a Drosophila pupa and the other from a chicken embryo; the pipeline results are robust. Perspectives include in vitro tissues, nonbiological cellular patterns such as foams and xyz stacks.


Asunto(s)
Forma de la Célula , Epitelio/diagnóstico por imagen , Análisis de Fourier , Imagen Molecular , Animales , Anisotropía , Fenómenos Biomecánicos , Tamaño de la Célula , Embrión de Pollo , Drosophila melanogaster/citología , Pupa/citología , Estrés Mecánico , Factores de Tiempo
14.
Biochim Biophys Acta Rev Cancer ; 1872(2): 188304, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31348974

RESUMEN

The concentration of sodium ions (Na+) is raised in solid tumours and can be measured at the cellular, tissue and patient levels. At the cellular level, the Na+ gradient across the membrane powers the transport of H+ ions and essential nutrients for normal activity. The maintenance of the Na+ gradient requires a large proportion of the cell's ATP. Na+ is a major contributor to the osmolarity of the tumour microenvironment, which affects cell volume and metabolism as well as immune function. Here, we review evidence indicating that Na+ handling is altered in tumours, explore our current understanding of the mechanisms that may underlie these alterations and consider the potential consequences for cancer progression. Dysregulated Na+ balance in tumours may open opportunities for new imaging biomarkers and re-purposing of drugs for treatment.


Asunto(s)
Neoplasias/metabolismo , Sodio/metabolismo , Adenosina Trifosfato/metabolismo , Tamaño de la Célula , Homeostasis , Humanos , Microambiente Tumoral
15.
J Mol Histol ; 50(5): 435-457, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31302827

RESUMEN

The claustrum is a subcortical nucleus, found in the telencephalon of all placental mammals. Earlier Golgi studies have mostly focused on a qualitative description of the types of neurons. The aim of the present study was to describe the types of neurons found in the dorsal claustrum of the cat using the Golgi impregnation method and to perform a quantitative analysis of the following morphometric parameters: number of terminals (ends), total dendritic length, dendritic complexity, spine density (in spiny projection neurons), varicosity density (in aspiny interneurons). We used specimens from 5 healthy male cats stained according to the Golgi-Cox method. The dendritic trees of the studied neurons were then reconstructed through the Neurolucida software. Values of the studied quantitative parameters were obtained automatically and tested for statistically significant differences. Five types of spiny neurons were observed-large, medium-sized and small multipolar, bipolar and pyramidal-like. In addition, we described three types of aspiny neurons. The quantitative values and the statistical analysis were presented with tables and diagrams. In conclusion, we have presented a detailed analysis of the cytoarchitecture of the DC of the cat and have reported the first quantitative data on a number of morphometric parameters.


Asunto(s)
/citología , Neuronas/citología , Animales , Gatos , Forma de la Célula , Tamaño de la Célula , Interpretación Estadística de Datos , Dendritas/ultraestructura , Masculino , Neuronas/ultraestructura , Programas Informáticos
16.
J Plant Res ; 132(5): 571-580, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31321606

RESUMEN

Many Arabidopsis thaliana genes have been reported to affect plant cell size by regulating the level of endoreduplication, which is a modified cell cycle. However, the role of endoreduplication on the altered cell size in these reports must be reconsidered based on a number of findings. First, not all plant species exhibit endoreduplication, which indicates that endoreduplication-driven cell size regulation is not universal among plants. Second, while ploidy level and cell size are correlated in the epidermal pavement cells of Arabidopsis leaves, the size of mesophyll cells appears to be comparatively uniform regardless of whether there is heterogeneity in the ploidy level. Third, changes in the cell sizes reported in mutant and transgenic Arabidopsis seem to be too large to be solely the result of altered endoreduplication level. Fourth, compensated cell enlargement, which is triggered by a severe decrease in cell proliferation in Arabidopsis leaves, is usually independent of altered endoreduplication. We re-examined the role of endoreduplication on cell-size regulation in Arabidopsis, mainly in leaves, and revealed biases in the previous studies. This paper provides an overview of the work carried out in the past decade, and presents rationale to correct the previous assumptions. Based on the considerations provided in this report, a re-examination of previous reports regarding the roles of mutations and/or transgenes in the regulation of cell size is recommended.


Asunto(s)
Arabidopsis/fisiología , Tamaño de la Célula , Endorreduplicación , Genes de Plantas , Hojas de la Planta/fisiología , Arabidopsis/genética , Mutación , Transgenes
17.
Int J Mol Sci ; 20(13)2019 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-31269711

RESUMEN

Bicuspid aortic valve (BAV), the most common congenital heart defect, is associated with an increased prevalence of aortic dilation, aortic rupture and aortic valve calcification. Endothelial cells (ECs) play a major role in vessel wall integrity. Little is known regarding EC function in BAV patients due to lack of patient derived primary ECs. Endothelial colony forming cells (ECFCs) have been reported to be a valid surrogate model for several cardiovascular pathologies, thereby facilitating an in vitro system to assess patient-specific endothelial dysfunction. Therefore, the aim of this study was to investigate cellular functions in ECFCs isolated from BAV patients. Outgrowth and proliferation of ECFCs from patients with BAV (n = 34) and controls with a tricuspid aortic valve (TAV, n = 10) were determined and related to patient characteristics. Interestingly, we were only able to generate ECFCs from TAV and BAV patients without aortic dilation, and failed to isolate ECFC colonies from patients with a dilated aorta. Analyzing EC function showed that while proliferation, cell size and endothelial-to-mesenchymal transition were similar in TAV and BAV ECFCs, migration and the wound healing capacity of BAV ECFCs is significantly higher compared to TAV ECFCs. Furthermore, calcification is blunted in BAV compared to TAV ECFCs. Our results reveal ECs dysfunction in BAV patients and future research is required to unravel the underlying mechanisms and to further validate ECFCs as a patient-specific in vitro model for BAV.


Asunto(s)
Válvula Aórtica/anomalías , Células Endoteliales/patología , Enfermedades de las Válvulas Cardíacas/patología , Adulto , Aorta/patología , Válvula Aórtica/patología , Movimiento Celular , Tamaño de la Célula , Células Cultivadas , Dilatación Patológica/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
19.
Biofabrication ; 11(4): 045013, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31290409

RESUMEN

Multicellular aggregated tissues have grown critically important in benchtop biomedical research, both as stand-alone spheroids and when assembled into larger bioengineered constructs. However, typical systems for aggregate formation are limited in their capacity to reliably handle such cultures at various experimental stages in a broadly accessible, consistent, and scalable manner. In this work, we develop a broadly versatile all-in-one biofabrication strategy to form uniform, spherical, multicellular aggregates that can be maintained at precisely defined positions for analysis or transfer into a larger tissue. The 3D-printed MicroPocket Culture (MPoC) system consists of an array of simple geometry-based valves in a polyacrylamide hydrogel, and is able to produce hundreds of uniformly-sized aggregates in standard tissue culture well plates, using simple tools that are readily available in all standard biological wet-labs. The model breast cancer aggregates formed in these experiments are retained in defined positions on chip during all liquid handling steps required to stimulate, label, and image the experiment, enabling high-throughput studies on this culture model. Furthermore, MPoCs enable robust formation of aggregates in cell types that do not conventionally form such structures. Finally, we demonstrate that this single platform can also be used to generate complex 3D tissues from the precisely-positioned aggregate building blocks. To highlight the unique and broad versatility of this technique, we develop a simple 3D invasion assay and show that cancer cells preferentially migrate towards nearby model tumors; demonstrating the importance of spatial precision when engineering 3D tissues. Together, this platform presents a broadly accessible and uniquely capable system with which to develop advanced aggregate-based models for tissue engineering, fundamental research, and applied drug discovery.


Asunto(s)
Hidrogeles/química , Microtecnología/instrumentación , Ingeniería de Tejidos/métodos , Agregación Celular , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Tamaño de la Célula , Matriz Extracelular/metabolismo , Humanos , Esferoides Celulares/citología
20.
Korean J Parasitol ; 57(3): 299-302, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31284354

RESUMEN

A clonorchiasis case in a captive leopard cat, Prionailurus bengalensis euptilurus, was confirmed by ultrasonographic findings and egg morphologies found in the bile juice sample in the Korea. The leopard cat was introduced from the wild habitat of Gyeongsangnam-do, to Cheongju Zoo in Cheongju-si, Chungcheongbuk-do, Korea in August 2014. Physical examinations were basically performed for quarantine and check-up health. The cat was comparatively good in health except anorexia. The cyst-like bile duct dilation and the increased echogenicity of gall bladder wall and hepatic parenchyma were observed by ultrasonography. Ultrasound-guided needle biopsy was conducted for collecting bile juice and the specimens were observed under light microscope. The numerous small trematode eggs were detected in the bile juice sample of the light microscopy. The eggs were 25-33 (28±3) µm by 18-22 (20±1) µm in size and showed typical characteristics of Clonorchis sinensis egg, i.e., a dominantly developed operculum, shoulder rim and dust-like wrinkles in surface. To treat the liver fluke infection, 20 mg/kg of praziquantel was orally administered only once to the case. Follow-up studies including fecal examinations were conducted during 2 years after treatment. But no more eggs were detected from the case. In the present study, we described the first clonorchiasis case of leopard cat, which was confirmed by ultrasonographic findings and egg morphologies from the bile juice sample in Korea.


Asunto(s)
Clonorquiasis/veterinaria , Clonorchis sinensis/aislamiento & purificación , Panthera/parasitología , Animales , Antihelmínticos/uso terapéutico , Bilis/parasitología , Tamaño de la Célula , Clonorquiasis/diagnóstico por imagen , Clonorquiasis/tratamiento farmacológico , Clonorquiasis/parasitología , Clonorchis sinensis/efectos de los fármacos , Clonorchis sinensis/crecimiento & desarrollo , Óvulo/citología , Óvulo/efectos de los fármacos , Óvulo/crecimiento & desarrollo , Praziquantel/uso terapéutico , República de Corea , Ultrasonografía
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