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1.
Int J Mol Sci ; 25(1)2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38203380

RESUMEN

The ability of materials to adhere bacteria on their surface is one of the most important aspects of their development and application in bioengineering. In this work, the effect of the properties of films and electrospun scaffolds made of composite materials based on biosynthetic poly(3-hydroxybutyrate) (PHB) with the addition of magnetite nanoparticles (MNP) and their complex with graphene oxide (MNP/GO) on the adhesion of E. coli and L. fermentum under the influence of a low-frequency magnetic field and without it was investigated. The physicochemical properties (crystallinity; surface hydrophilicity) of the materials were investigated by X-ray structural analysis, differential scanning calorimetry and "drop deposition" methods, and their surface topography was studied by scanning electron and atomic force microscopy. Crystal violet staining made it possible to reveal differences in the surface charge value and to study the adhesion of bacteria to it. It was shown that the differences in physicochemical properties of materials and the manifestation of magnetoactive properties of materials have a multidirectional effect on the adhesion of model microorganisms. Compared to pure PHB, the adhesion of E. coli to PHB-MNP/GO, and for L. fermentum to both composite materials, was higher. In the magnetic field, the adhesion of E. coli increased markedly compared to PHB-MNP/GO, whereas the effect on the adhesion of L. fermentum was reversed and was only evident in samples with PHB-MNP. Thus, the resultant factors enhancing and impairing the substrate binding of Gram-negative E. coli and Gram-positive L. fermentum turned out to be multidirectional, as they probably have different sensitivity to them. The results obtained will allow for the development of materials with externally controlled adhesion of bacteria to them for biotechnology and medicine.


Asunto(s)
Limosilactobacillus fermentum , Nanopartículas de Magnetita , Polihidroxibutiratos , Ácido 3-Hidroxibutírico , Escherichia coli , Campos Magnéticos
2.
Phys Chem Chem Phys ; 24(43): 26848-26852, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36317506

RESUMEN

One of the striking characteristics of the tris(alkoxo)-ligated Lindqvist-type polyoxovanadates [VV6O13{(OCH2)3CR}2]2- in highest oxidation state in solution is the ease of their chemical post-functionalization via the R group. On surfaces it is their conductivity as a function of individual V(3d) redox states. In both cases, the structural stability of the fully-oxidized dianion is enabled by charge-balancing counterions. In this Article, we explore the charge stability and the charge distibution across the molecular Lindqvist-type hexavanadate structure regarding the R functionality (R = OC2H4N3, CH2N3, and O3C29H36N5) and the different type of countercations (Cat = K+, Li+, NH4+, H+, or Mg2+). We show that the hexavanadate core can accept in its vacant V(3d) orbitals at least four and, in some cases, up to nine additional electrons if the negative charge is offset by the corresponding cation(s), without electron leakage to the covalently attached R groups. Remarkably, the maximum number of accepted electrons strongly depends on the type of cation(s) and is independent on the type of the remote R group exploited herein. The (Cat)n[VV6O13{(OCH2)3CR}2] complexes exibit the structural integrity in all studied charged states. Our study demonstrates the importance of the countercations of multistate polyoxovanadate nanoswitches for the development of multi-charge based molecular memories and/or batteries.


Asunto(s)
Suministros de Energía Eléctrica , Electrones , Estructura Molecular , Oxidación-Reducción , Cationes
3.
Angew Chem Int Ed Engl ; 61(20): e202116653, 2022 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-35274425

RESUMEN

Peptide receptor radionuclide therapy is used to treat solid tumors by locally delivering radiation. However, due to nephro- and hepato-toxicity, it is limited by its dosage. To amplify radiation damage to tumor cells, radiolabeled nanogels can be used. We show that by tuning the mechanical properties of nanogels significant enhancement in circulation half-life of the gel could be achieved. We demonstrate why and how small changes in the mechanical properties of the nanogels influence its cellular fate. Nanogels with a storage modulus of 37 kPa were minimally phagocytosed by monocytes and macrophages compared to nanogels with 93 kPa modulus. Using PET/CT a significant difference in the blood circulation time of the nanogels was shown. Computer simulations affirmed the results and predicted the mechanism of cellular uptake of the nanogels. Altogether, this work emphasizes the important role of elasticity even for particles that are inherently soft such as nano- or microgels.


Asunto(s)
Microgeles , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tiempo de Circulación Sanguínea , Elasticidad , Nanogeles
4.
Neuroimage ; 238: 118250, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34116154

RESUMEN

Mammalian neurons operate at length scales spanning six orders of magnitude; they project millimeters to centimeters across brain regions, are composed of micrometer-scale-diameter myelinated axons, and ultimately form nanometer scale synapses. Capturing these anatomical features across that breadth of scale has required imaging samples with multiple independent imaging modalities. Translating between the different modalities, however, requires imaging the same brain with each. Here, we imaged the same postmortem mouse brain over five orders of spatial resolution using MRI, whole brain micrometer-scale synchrotron x-ray tomography (µCT), and large volume automated serial electron microscopy. Using this pipeline, we can track individual myelinated axons previously relegated to axon bundles in diffusion tensor MRI or arbitrarily trace neurons and their processes brain-wide and identify individual synapses on them. This pipeline provides both an unprecedented look across a single brain's multi-scaled organization as well as a vehicle for studying the brain's multi-scale pathologies.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen Multimodal/métodos , Animales , Conectoma , Imagen por Resonancia Magnética , Ratones , Microscopía Electrónica , Tomografía Computarizada por Rayos X
5.
Respirology ; 19(6): 907-13, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24909555

RESUMEN

BACKGROUND AND OBJECTIVE: Probe-based confocal laser endoscopy (pCLE) allows for real-time non-invasive histological imaging via bronchoscopy. Interpreting CLE images and correlating with traditional histopathology remains challenging. We performed an ex vivo study to evaluate the correlation between light microscopy findings and pCLE imaging of primary lung carcinoma. METHODS: Post-lobectomy specimens for lung cancer nodules were examined ex vivo by pCLE. The examined areas were marked with brilliant green dye, and the surrounding tissues were stained by methylene blue dye. Lung tissue segments were resected and histopathological specimens were generated with 50-µm thickness from the marked areas and stained with haematoxylin and eosin. Pathologists and pulmonologists reviewed the images for correlating features. RESULTS: Eighteen lobectomy specimens from 18 different patients were collected. Three primary features were observed in all samples using pCLE in the cancer surroundings: alveolar dystelectasis with thickening of alveolar walls, alveolar edema and a large amount of macrophages. The stromal and parenchymal components of the studied subtypes of non-small-cell lung cancer differed from each other. The stromal component for all nine adenocarcinoma specimens had a highly fluorescent field penetrated by dark hollows. All six squamous cell carcinoma specimens had the stromal component appeared as 'biparously' branching, highly fluorescent fibres. No stromal component was observed in any small-cell carcinoma specimen, and at low power field, the cellular component was dominant with an observed light scattering pattern. CONCLUSIONS: pCLE can identify lung carcinoma in ex vivo samples. Certain light microscopy features of lung carcinoma can be visualized with pCLE.


Asunto(s)
Adenocarcinoma/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Microscopía Confocal/métodos , Microscopía/métodos , Adenocarcinoma/patología , Anciano , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/patología , Diagnóstico Diferencial , Femenino , Humanos , Pulmón/patología , Pulmón/cirugía , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neumonectomía , Reproducibilidad de los Resultados
6.
Nat Commun ; 14(1): 8018, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049416

RESUMEN

The neotenous, or delayed, development of primate neurons, particularly human ones, is thought to underlie primate-specific abilities like cognition. We tested whether synaptic development follows suit-would synapses, in absolute time, develop slower in longer-lived, highly cognitive species like non-human primates than in shorter-lived species with less human-like cognitive abilities, e.g., the mouse? Instead, we find that excitatory and inhibitory synapses in the male Mus musculus (mouse) and Rhesus macaque (primate) cortex form at similar rates, at similar times after birth. Primate excitatory and inhibitory synapses and mouse excitatory synapses also prune in such an isochronic fashion. Mouse inhibitory synapses are the lone exception, which are not pruned and instead continuously added throughout life. The monotony of synaptic development clocks across species with disparate lifespans, experiences, and cognitive abilities argues that such programs are likely orchestrated by genetic events rather than experience.


Asunto(s)
Neuronas , Sinapsis , Ratones , Animales , Masculino , Macaca mulatta , Sinapsis/fisiología , Neuronas/fisiología , Cognición
7.
J Homosex ; 69(5): 796-820, 2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33428563

RESUMEN

Previous studies have shown that ambivalent gender attitudes are associated with attitudes toward homosexuals. However, most of these studies have primarily considered ambivalent attitudes toward women and attitudes toward gay men, and have been carried out in countries with progressive laws regarding homosexuality. In this study, we examined the connection between ambivalent attitudes toward men and women and attitudes toward gay men and lesbian women in countries with conservative sexual legislation. In the first study, participants were residents of Russia (N = 163) and Kazakhstan (N = 194), while the second study used residents of Russia (N = 496) and Belarus (N = 123). Results indicated that benevolent attitudes predicted attitudes toward gays and lesbians better than the hostile ones. At the same time, attitudes toward men and women similarly predicted attitudes toward gays and lesbians. These patterns were manifested among different components of attitudes toward homosexuals. The results are discussed within the social context of the countries.


Asunto(s)
Homosexualidad Femenina , Minorías Sexuales y de Género , Actitud , Femenino , Humanos , Kazajstán , Masculino , República de Belarús
8.
Elife ; 102021 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-34965204

RESUMEN

Dopaminergic (DA) neurons exert profound influences on behavior including addiction. However, how DA axons communicate with target neurons and how those communications change with drug exposure remains poorly understood. We leverage cell type-specific labeling with large volume serial electron microscopy to detail DA connections in the nucleus accumbens (NAc) of the mouse (Mus musculus) before and after exposure to cocaine. We find that individual DA axons contain different varicosity types based on their vesicle contents. Spatially ordering along individual axons further suggests that varicosity types are non-randomly organized. DA axon varicosities rarely make specific synapses (<2%, 6/410), but instead are more likely to form spinule-like structures (15%, 61/410) with neighboring neurons. Days after a brief exposure to cocaine, DA axons were extensively branched relative to controls, formed blind-ended 'bulbs' filled with mitochondria, and were surrounded by elaborated glia. Finally, mitochondrial lengths increased by ~2.2 times relative to control only in DA axons and NAc spiny dendrites after cocaine exposure. We conclude that DA axonal transmission is unlikely to be mediated via classical synapses in the NAc and that the major locus of anatomical plasticity of DA circuits after exposure to cocaine are large-scale axonal re-arrangements with correlated changes in mitochondria.


Asunto(s)
Axones/efectos de los fármacos , Cocaína/farmacología , Conectoma , Neuronas Dopaminérgicas/efectos de los fármacos , Animales , Axones/ultraestructura , Neuronas Dopaminérgicas/ultraestructura , Ratones , Ratones Transgénicos , Microscopía Electrónica , Mitocondrias/ultraestructura , Núcleo Accumbens/efectos de los fármacos
9.
Biomed Opt Express ; 12(9): 5597-5613, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34692203

RESUMEN

Adequate tumor yield in core-needle biopsy (CNB) specimens is essential in lung cancer for accurate histological diagnosis, molecular testing for therapeutic decision-making, and tumor biobanking for research. Insufficient tumor sampling in CNB is common, primarily due to inadvertent sampling of tumor-associated fibrosis or atelectatic lung, leading to repeat procedures and delayed diagnosis. Currently, there is no method for rapid, non-destructive intraprocedural assessment of CNBs. Polarization-sensitive optical coherence tomography (PS-OCT) is a high-resolution, volumetric imaging technique that has the potential to meet this clinical need. PS-OCT detects endogenous tissue properties, including birefringence from collagen, and degree of polarization uniformity (DOPU) indicative of tissue depolarization. Here, PS-OCT birefringence and DOPU measurements were used to quantify the amount of tumor, fibrosis, and normal lung parenchyma in 42 fresh, intact lung CNB specimens. PS-OCT results were compared to and validated against matched histology in a blinded assessment. Linear regression analysis showed strong correlations between PS-OCT and matched histology for quantification of tumors, fibrosis, and normal lung parenchyma in CNBs. PS-OCT distinguished CNBs with low tumor content from those with higher tumor content with high sensitivity and specificity. This study demonstrates the potential of PS-OCT as a method for rapid, non-destructive, label-free intra-procedural tumor yield assessment.

10.
Int J Womens Health ; 13: 525-537, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34104002

RESUMEN

OBJECTIVE: To review the mechanisms of endometriosis development, including those related to epigenetic mutations, cellular dysregulation, inflammatory processes, and oxidative stress. METHODS: A systematic literature review regarding current aspects of endometriosis etiology, genesis and development was performed using the PubMed, Google Scholar, and eLibrary databases. Keywords included endometriosis, etiology, development, genesis, associations and mechanisms. A multilingual search was performed. RESULTS: Several mechanisms underline the pathophysiological pathways for endometriosis development. Epigenetic mutations, external and internal influences, and chronic conditions have a significant impact on endometriosis development, survival and regulation. Several historically valid theories on endometriosis development were discussed, as well as updated findings. CONCLUSION: Despite recent advances, fundamental problems in understanding endometriosis remain unresolved. The identification of unknown circulating epithelial progenitors or stem cells that are responsible for epithelial growth in both the endometrium and endometriotic foci seems to be the next step in solving these questions.

12.
J Colloid Interface Sci ; 564: 344-356, 2020 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-31918202

RESUMEN

Thermoresponsive copolymer microgels based on the biocompatible monomer N-vinylcaprolactam (VCL) and the hydrophobic comonomer 4-tert-butylcyclohexylacrylate (TBCHA) with highly tunable comonomers ratio were for the first time synthesized by miniemulsion polymerization. Their physical properties in aqueous solution and at the solid interface were characterized using dynamic light scattering (DLS), atomic force microscopy (AFM) and dissipative particle dynamics (DPD) simulations. The results show a significant decrease of the swelling rate of the obtained microgels with an increase of the amount of the hydrophobic comonomer. In the case when the fraction of TBCHA is equal or higher than the fraction of VCL, the microgels become almost insensitive to the temperature changes, and the amount of water inside the microgels appeared to be diminishingly small. In the opposite case, if the VCL fraction is major, the copolymer microgels preserve their softness and deformability while being adsorbed onto a solid surface. At the same time, all samples have shown a good colloidal stability and a low polydispersity in size. Thus, the presented polymerization technique is applicable for the fabrication of microgels using hydrophobic monomers, which are not accessible by conventional precipitation polymerization. We demonstrate that the mechanical properties and the temperature-responsiveness of the copolymer microgels can be precisely adjusted by the content of the hydrophobic comonomer.

13.
Arch Pathol Lab Med ; 143(3): 288-298, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30525931

RESUMEN

The traditional surgical pathology assessment requires tissue to be removed from the patient, then processed, sectioned, stained, and interpreted by a pathologist using a light microscope. Today, an array of alternate optical imaging technologies allow tissue to be viewed at high resolution, in real time, without the need for processing, fixation, freezing, or staining. Optical imaging can be done in living patients without tissue removal, termed in vivo microscopy, or also in freshly excised tissue, termed ex vivo microscopy. Both in vivo and ex vivo microscopy have tremendous potential for clinical impact in a wide variety of applications. However, in order for these technologies to enter mainstream clinical care, an expert will be required to assess and interpret the imaging data. The optical images generated from these imaging techniques are often similar to the light microscopic images that pathologists already have expertise in interpreting. Other clinical specialists do not have this same expertise in microscopy, therefore, pathologists are a logical choice to step into the developing role of microscopic imaging expert. Here, we review the emerging technologies of in vivo and ex vivo microscopy in terms of the technical aspects and potential clinical applications. We also discuss why pathologists are essential to the successful clinical adoption of such technologies and the educational resources available to help them step into this emerging role.


Asunto(s)
Diagnóstico por Imagen/métodos , Microscopía/métodos , Imagen Óptica/métodos , Patología Quirúrgica/métodos , Anciano , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad
14.
PLoS One ; 13(8): e0201553, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30110355

RESUMEN

Despite the prevalence and high heritability of Attention-Deficit/Hyperactivity Disorder (ADHD), genetic etiology remains elusive. Clinical evidence points in part to reduced function of the striatum, but which specific genes are differentially expressed and how they sculpt striatal physiology to predispose ADHD are not well understood. As an exploratory tool, a polygenic mouse model of ADHD was recently developed through selective breeding for high home cage activity. Relative to the Control line, the High-Active line displays hyperactivity and motor impulsivity which are ameliorated with amphetamine. This study compared gene expression in the striatum between Control and High-Active mice to develop a coherent hypothesis for how genes might affect striatal physiology and predispose ADHD-like symptoms. To this end, striatal transcriptomes of High-Active and Control mice were analyzed after mice were treated with saline or amphetamines. The pseudogene Gm6180 for n-cofilin (Cfl1) displayed 20-fold higher expression in High-Active mice corresponding with reduced Cfl1 expression suggesting synaptic actin dysregulation. Latrophilin 3 (Lphn3), which is associated with ADHD in human populations and is involved in synapse structure, and its ligand fibronectin leucine rich transmembrane protein 3 (Flrt3), were downregulated in High-Active mice. Multiple genes were altered in High-Active mice in a manner predicted to downregulate the canonical Wnt pathway. A smaller and different set of genes including glyoxalase (Glo1) were differentially regulated in High-Active as compared to Control in response to amphetamine. Together, results suggest genes involved in excitatory synapse regulation and maintenance are downregulated in ADHD-like mice. Consistent with the molecular prediction, stereological analysis of the striatum from a separate set of mice processed for imunohistochemical detection of synaptophysin revealed approximately a 46% reduction in synaptophysin immunoreactivity in High-Active relative to Control. Results provide a new set of molecular targets related to synapse maintenance for the next generation of ADHD medicines.


Asunto(s)
Anfetaminas/efectos adversos , Trastorno por Déficit de Atención con Hiperactividad/genética , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia de ARN/métodos , Corteza Visual/química , Animales , Trastorno por Déficit de Atención con Hiperactividad/inducido químicamente , Cofilina 1/genética , Modelos Animales de Enfermedad , Potenciales Postsinápticos Excitadores , Regulación de la Expresión Génica , Humanos , Lactoilglutatión Liasa/genética , Masculino , Glicoproteínas de Membrana/genética , Ratones , Seudogenes , Receptores Acoplados a Proteínas G/genética , Receptores de Péptidos/genética , Vía de Señalización Wnt
16.
J Bronchology Interv Pulmonol ; 22(1): 33-40, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25590481

RESUMEN

BACKGROUND: The diagnosis of pulmonary alveolar proteinosis (PAP) is based on computed tomography, histology, and antibodies to granulocyte-macrophage colony-stimulating factor. The role of a novel technique for imaging cells and elastin during endoscopy, probe-based confocal laser endomicroscopy (pCLE), has not yet been investigated in PAP patients. The aim of the present study was to estimate the value of pCLE in the PAP diagnosis and treatment in comparison with the findings of high-resolution computed tomography (HRCT) before and after whole-lung lavage. METHODS: In vivo pCLE was performed during bronchoscopy in 6 male patients with PAP before and after whole-lung lavage. In certain lung segments, pCLE was followed by HRCT. RESULTS: During the in vivo pCLE, we found characteristic signs of PAP: a fluorescent floating amorphous substance in the alveoli lumen sticking to conglomerates along with alveolar macrophages. These features were present to a lesser extent after a whole-lung lavage. pCLE revealed specific PAP features not only in segments with crazy-paving and ground-glass opacity, but also in segments without HRCT findings. CONCLUSIONS: The alveolar imaging in PAP patients is able to reveal characteristic changes, both in the presence and in the absence of HRCT findings. Therefore, pCLE may be a helpful tool for the diagnosis and whole-lung lavage therapy. Our data prove that accumulation of lipoproteinaceous substances within the alveoli at PAP is a diffuse but not a patchy process.


Asunto(s)
Broncoscopía/métodos , Microscopía Confocal/métodos , Proteinosis Alveolar Pulmonar/diagnóstico , Adulto , Lavado Broncoalveolar/métodos , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteinosis Alveolar Pulmonar/terapia , Tomógrafos Computarizados por Rayos X
17.
Med Mycol Case Rep ; 5: 35-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25180153

RESUMEN

We present a case of 41-year-old patient with invasive pulmonary aspergillosis (IPA) in which probe-based confocal laser endomicroscopy (pCLE) imaging of central and distal airways was first performed in vivo. pCLE imaging showed the signs of complete or partial destruction of elastin network of alveolar wall with fibrillar branching fluorescent structures in the zone with typical IPA changes on HRCT.

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