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1.
Biomed Mater ; 19(5)2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39025122

RESUMEN

The majority of research on nanomaterials has been concentrated on metal nanoparticles since they are easily made and manipulated. Nanomaterials have shown a wide range of applications in biology. Nevertheless, their bioactivity declines due to their extreme susceptibility to and novel Se@ZIF-8 by chemical method. The sizes and morphologies of Se (0) and Se@ZIFchemical and physical stimuli. The goal of encapsulating these nanomaterials in a matrix is gradually being pursued, which boosts their affordability, stability, and usability. Metal-organic frameworks, often known as MOFs, have the potential to be the best platforms for encapsulating metal nanoparticles due to their well-defined frameworks, persistent porosity, and flexibility in modification. In this investigation, we report the synthesis and optimization of polyvinylpyrrolidone-stabilized Se(0) nanoparticles -8 were affected by the ratios of Se/Zn2+and [hmim]/Zn2+used. The optimized Se@ZIF-8 nanoparticles exhibited a particle size and zeta potential of 319 nm and -34 mv respectively. Transmission electron microscopy displayed spherical morphology for Se(0) nanoparticles, whereas the surface morphology of novel Se@ZIF-8 nanoparticles was drastically changed to hexagonal shaped structures with smooth surface morphologies in scanning electron microscopy (SEM). The DTA, TG/DTG, XRD analysis confirmed the presence of novel Se incorporated ZIF-8 nanoparticulate framework. The synthesized novel Se@ZIF-8 nanoparticles showed efficient antibacterial activity as evidenced by low MIC values. Interestingly, these Se@ZIF-8 NPs not only inhibited biofilm formation inS. marcescens,but also effectively eradicated mature biofilms by degrading the eDNA of the EPS layer. It was validated by confocal laser scanning microscopy and SEM analysis. It was observed that Se@ZIF-8 targeted the Quroum Sensing pathway and reduced its associated virulence factors production. This work opens up a different approach of Se@ZIF-8 nanoparticles as novel antibiotics to treat biofilm-associated infections caused byS. marcescensand offer a solution for antimicrobial resistance.


Asunto(s)
Antibacterianos , Biopelículas , Estructuras Metalorgánicas , Percepción de Quorum , Biopelículas/efectos de los fármacos , Percepción de Quorum/efectos de los fármacos , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Tamaño de la Partícula , Selenio/química , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Nanopartículas/química , Ensayo de Materiales , Povidona/química , Zinc/química , Zinc/farmacología , Microscopía Electrónica de Transmisión , Imidazoles
2.
Environ Geochem Health ; 46(9): 327, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012555

RESUMEN

The novel bioengineered CuO nanoparticles were successfully synthesized directly using green chemistry, the nontoxic and renewable aqueous extract of waste papaya peel (Carica papaya) as a precursor. The XRD analysis indicated a monoclinic phase of CuO nanoparticles and a size of 20 nm, and the optical absorption analysis showed a peak in the 264 nm range. In TEM, the morphology of the NPs was observed to be almost spherical with a particle size of 15 nm. The CuO nanoparticles showed good efficiency in the degradation of methylene, obtaining up to 50% in 40 min using 6 mg in 60 ml of MB at 10 mg/L. The novel presented in this work derives from using rock minerals, from which we have directly obtained copper salt and copper oxide nanoparticles. This process not only utilizes ecological green chemistry but also offers an economic advantage by directly producing nanoparticles from the mineral instead of purchasing costly pure chemical reagents and employing novel nanomaterials to purify wastewater.


Asunto(s)
Colorantes , Cobre , Nanopartículas del Metal , Cobre/química , Colorantes/química , Nanopartículas del Metal/química , Contaminantes Químicos del Agua/química , Catálisis , Tecnología Química Verde/métodos , Carica/química , Minería , Difracción de Rayos X , Azul de Metileno/química , Microscopía Electrónica de Transmisión
3.
Int J Mol Sci ; 25(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-39000109

RESUMEN

Surface modification of drug-loaded particles with polyethylene glycol (PEG) chains is a powerful tool that promotes better transport of therapeutic agents, provides stability, and avoids their detection by the immune system. In this study, we used a new approach to synthesize a biodegradable poly(ester amide) (PEA) and PEGylating surfactant. These were employed to fabricate micro/nanoparticles with a core-shell structure. Nanoparticle (NP)-protein interactions and self-assembling were subsequently studied by synchrotron radiation-based FTIR microspectroscopy (SR-FTIRM) and transmission electron microscopy (TEM) techniques. The core-shell structure was identified using IR absorption bands of characteristic chemical groups. Specifically, the stretching absorption band of the secondary amino group (3300 cm-1) allowed us to identify the poly(ester amide) core, while the band at 1105 cm-1 (C-O-C vibration) was useful to demonstrate the shell structure based on PEG chains. By integration of absorption bands, a 2D intensity map of the particle was built to show a core-shell structure, which was further supported by TEM images.


Asunto(s)
Nanopartículas , Poliésteres , Polietilenglicoles , Sincrotrones , Polietilenglicoles/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Nanopartículas/química , Poliésteres/química , Microscopía Electrónica de Transmisión/métodos , Amidas/química
4.
Invest Ophthalmol Vis Sci ; 65(8): 4, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38953845

RESUMEN

Purpose: The purpose of this study was to investigate the role and mechanism of microtubule-associated protein light chain-3 (LC3)-associated phagocytosis (LAP) in the immune response to Aspergillus fumigatus (A. fumigatus) keratitis. Methods: The formation of single-membrane phagosomes was visualized in the corneas of healthy or A. fumigatus-infected humans and C57BL/6 mice using transmission electron microscopy (TEM). Rubicon siRNA (si-Rubicon) was used to block Rubicon expression. RAW 264.7 cells or mice corneas were infected with A. fumigatus with or without pretreatment of si-Rubicon and scrambled siRNA. RAW 264.7 cells were pretreated with Dectin-1 antibody or Dectin-1 overexpressed plasmid and then stimulated with A. fumigatus. Flow cytometry was used to label macrophages in normal and infected corneas of mice. In mice with A. fumigatus keratitis, the severity of the disease was assessed using clinical scores. We used lentiviral technology to transfer GV348-Ubi-GFP-LC3-II-SV40-Puro Lentivirus into the mouse cornea. The GFP-LC3 fusion protein was visualized in corneal slices using a fluorescence microscope. We detected the mRNA and protein expressions of the inflammatory factors IL-6, IL-1ß, and IL-10 using real-time PCR (RT-PCR) and ELISA. We detected the expression of LAP-related proteins Rubicon, ATG-7, Beclin-1, and LC3-II using Western blot or immunofluorescence. Results: Accumulation of single-membrane phagosomes within macrophages was observed in the corneas of patients and mice with A. fumigatus keratitis using TEM. Flow cytometry (FCM) analysis results show that the number of macrophages in the cornea of mice significantly increases after infection with A. fumigatus. LAP-related proteins were significantly elevated in the corneas of mice and RAW 264.7 cells after infection with A. fumigatus. The si-Rubicon treatment elevated the clinical score of mice. In A. fumigatus keratitis mice, the si-Rubicon treated group showed significantly higher expression of IL-6 and IL-1ß and lower expression of IL-10 and LC3-II compared to the control group. In RAW 264.7 cells, treatment with the Dectin-1 overexpressed plasmid upregulated the expression of LAP-related proteins, a process that was significantly inhibited by the Dectin-1 antibody. Conclusions: LAP participates in the anti-inflammatory immune process of fungal keratitis (FK) and exerts an anti-inflammatory effect. LAP is regulated through the Dectin-1 signaling pathway in A. fumigatus keratitis.


Asunto(s)
Aspergilosis , Aspergillus fumigatus , Infecciones Fúngicas del Ojo , Queratitis , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos , Fagocitosis , Animales , Femenino , Humanos , Ratones , Aspergilosis/microbiología , Aspergilosis/metabolismo , Aspergilosis/inmunología , Córnea/metabolismo , Córnea/microbiología , Córnea/patología , Modelos Animales de Enfermedad , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/metabolismo , Citometría de Flujo , Queratitis/microbiología , Queratitis/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología , Microscopía Electrónica de Transmisión , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética
5.
Clin Exp Rheumatol ; 42(6): 1215-1223, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38966946

RESUMEN

OBJECTIVES: The pathogenesis of fibromyalgia (FM), characterised by chronic widespread pain and fatigue, remains notoriously elusive, hampering attempts to develop disease modifying treatments. Mitochondria are the headquarters of cellular energy metabolism, and their malfunction has been proposed to contribute to both FM and chronic fatigue. Thus, the aim of the current pilot study, was to detect structural changes in mitochondria of peripheral blood mononuclear cells (PBMCs) of FM patients, using transmission electron microscopy (TEM). METHODS: To detect structural mitochondrial alterations in FM, we analysed PBMCs from seven patients and seven healthy controls, using TEM. Patients were recruited from a specialised Fibromyalgia Clinic at a tertiary medical centre. After providing informed consent, participants completed questionnaires including the widespread pain index (WPI), symptoms severity score (SSS), fibromyalgia impact questionnaire (FIQ), beck depression inventory (BDI), and visual analogue scale (VAS), to verify a diagnosis of FM according to ACR criteria. Subsequently, blood samples were drawn and PBMCs were collected for EM analysis. RESULTS: TEM analysis of PBMCs showed several distinct mitochondrial cristae patterns, including total loss of cristae in FM patients. The number of mitochondria with intact cristae morphology was reduced in FM patients and the percentage of mitochondria that completely lacked cristae was increased. These results correlated with the WPI severity. Moreover, in the FM patient samples we observed a high percentage of cells containing electron dense aggregates, which are possibly ribosome aggregates. Cristae loss and possible ribosome aggregation were intercorrelated, and thus may represent reactions to a shared cellular stress condition. The changes in mitochondrial morphology suggest that mitochondrial dysfunction, resulting in inefficient oxidative phosphorylation and ATP production, metabolic and redox disorders, and increased reactive oxygen species (ROS) levels, may play a pathogenetic role in FM. CONCLUSIONS: We describe novel morphological changes in mitochondria of FM patients, including loss of mitochondrial cristae. While these observations cannot determine whether the changes are pathogenetic or represent an epiphenomenon, they highlight the possibility that mitochondrial malfunction may play a causative role in the cascade of events leading to chronic pain and fatigue in FM. Moreover, the results offer the possibility of utilising changes in mitochondrial morphology as an objective biomarker in FM. Further understanding the connection between FM and dysfunction of mitochondria physiology, may assist in developing both novel diagnostic tools as well as specific treatments for FM, such as approaches to improve/strengthen mitochondria function.


Asunto(s)
Fibromialgia , Mitocondrias , Humanos , Fibromialgia/patología , Fibromialgia/fisiopatología , Proyectos Piloto , Mitocondrias/ultraestructura , Mitocondrias/patología , Femenino , Persona de Mediana Edad , Adulto , Estudios de Casos y Controles , Masculino , Microscopía Electrónica de Transmisión , Leucocitos Mononucleares/ultraestructura , Leucocitos Mononucleares/patología , Índice de Severidad de la Enfermedad , Dimensión del Dolor
6.
Parasitol Int ; 102: 102910, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38825165

RESUMEN

Sarcocystis spp. are cyst-forming coccidia characterized by a two-host predator-prey life cycle. Sarcocysts are formed in muscles or nervous system of the intermediate host, while sporocysts develop in the small intestine of the definitive host. The intermediate hosts of Sarcocystis falcatula are wild birds. Colombia is one of the countries with the greatest biodiversity of birds, however, there are few studies related to this parasite in wild birds. This study presents the morphological and molecular detection of Sarcocystis falcatula collected from the emerald toucanet (Aulacorhynchus albivitta), a wild bird species endemic to South America. Pectoral muscle samples were obtained, and microscopic and molecular detection was performed by light microscopy, transmission electron microscopy, and amplifying of the first internal transcribed spacer (ITS-1) and surface antigen-encoding genes (SAGs). Sarcocystis measured an average of 161  × 42 µm, with a cyst wall ∼0.4 µm thick. Ultrastructurally, the sarcocyst wall type 11b-like consisted of numerous villar protrusions of 850 nm wide on average. The ITS-1 sequence showed 97.0-99.7% identity to S. falcatula previously described from birds in the United States and Brazil, respectively. Concatenated phylogenetic analysis based on SAG2, SAG3 and SAG4 confirmed that the new isolate is grouped with other sequences of Sarcocystis from South America, but divergent from those isolates obtained in North America. The results of this study demonstrate for the first time the presence of S. falcatula in a wild bird from Colombia.


Asunto(s)
Enfermedades de las Aves , Sarcocystis , Sarcocistosis , Animales , Sarcocystis/genética , Sarcocystis/clasificación , Sarcocystis/aislamiento & purificación , Sarcocystis/ultraestructura , Sarcocistosis/veterinaria , Sarcocistosis/parasitología , Sarcocistosis/epidemiología , Colombia , Enfermedades de las Aves/parasitología , Filogenia , Microscopía Electrónica de Transmisión/veterinaria , ADN Protozoario/análisis , Falconiformes/parasitología
7.
Exp Eye Res ; 245: 109956, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38849003

RESUMEN

Exposure to particulate matters in air pollution of 2.5 µm or less (PM2.5) was associated with loss of meibomian glands. The aim of this study was to verify that PM2.5 could directly impact meibomian gland epithelial cells and damage their function. To investigate the impact of PM2.5 on meibomian gland, immortalized human meibomian gland epithelial cells were treated with various concentrations of PM2.5in vitro. Meibomian gland cell microstructure, cell viability, expression of proliferating cell nuclear antigen and IL-1ß, and intracellular accumulation of acidic vesicles were measured by transmission electron microscopy, cell counting, Western blot and LysoTracker staining, respectively. To further study the effect of PM2.5in vivo, male C57BL/6J mice were treated with 5 mg/ml PM2.5 or vehicle for 3 months. Corneal fluorescein staining and ocular examinations were done before and after the treatment. Eyelids tissues were processed for morphological studies, immunostaining and Oil Red O staining. Our data suggest that exposure to PM2.5 caused significant meibomian gland dropout, clogged gland orifice and increased corneal fluorescein staining that were consistent with the clinical presentations of meibomian gland dysfunction. Prominent changes in the morphology and ultrastructure of meibomian glands was observed with PM2.5 treatment. PM2.5 promoted ductal keratinization, inhibited cell proliferation, induced cell apoptosis and increased Interleukin-1ß production in meibomian gland epithelial cells. This study may explain the association between PM2.5 exposure and meibomian gland dropout observed in clinic. PM2.5 resuspension instillation could be used to induce a meibomian gland dysfunction animal model.


Asunto(s)
Supervivencia Celular , Células Epiteliales , Glándulas Tarsales , Ratones Endogámicos C57BL , Material Particulado , Material Particulado/toxicidad , Animales , Glándulas Tarsales/efectos de los fármacos , Glándulas Tarsales/metabolismo , Glándulas Tarsales/patología , Ratones , Masculino , Humanos , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/ultraestructura , Proliferación Celular/efectos de los fármacos , Western Blotting , Microscopía Electrónica de Transmisión , Disfunción de la Glándula de Meibomio/inducido químicamente , Disfunción de la Glándula de Meibomio/metabolismo , Modelos Animales de Enfermedad , Recuento de Células , Interleucina-1beta/metabolismo , Células Cultivadas , Apoptosis/efectos de los fármacos
8.
Cell Commun Signal ; 22(1): 269, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745240

RESUMEN

BACKGROUND: The pathway involving PTEN-induced putative kinase 1 (PINK1) and PARKIN plays a crucial role in mitophagy, a process activated by artesunate (ART). We propose that patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis exhibit insufficient mitophagy, and ART enhances mitophagy via the PINK1/PARKIN pathway, thereby providing neuroprotection. METHODS: Adult female mice aged 8-10 weeks were selected to create a passive transfer model of anti-NMDAR encephalitis. We conducted behavioral tests on these mice within a set timeframe. Techniques such as immunohistochemistry, immunofluorescence, and western blotting were employed to assess markers including PINK1, PARKIN, LC3B, p62, caspase3, and cleaved caspase3. The TUNEL assay was utilized to detect neuronal apoptosis, while transmission electron microscopy (TEM) was used to examine mitochondrial autophagosomes. Primary hippocampal neurons were cultured, treated, and then analyzed through immunofluorescence for mtDNA, mtROS, TMRM. RESULTS: In comparison to the control group, mitophagy levels in the experimental group were not significantly altered, yet there was a notable increase in apoptotic neurons. Furthermore, markers indicative of mitochondrial leakage and damage were found to be elevated in the experimental group compared to the control group, but these markers showed improvement following ART treatment. ART was effective in activating the PINK1/PARKIN pathway, enhancing mitophagy, and diminishing neuronal apoptosis. Behavioral assessments revealed that ART ameliorated symptoms in mice with anti-NMDAR encephalitis in the passive transfer model (PTM). The knockdown of PINK1 led to a reduction in mitophagy levels, and subsequent ART intervention did not alleviate symptoms in the anti-NMDAR encephalitis PTM mice, indicating that ART's therapeutic efficacy is mediated through the activation of the PINK1/PARKIN pathway. CONCLUSIONS: At the onset of anti-NMDAR encephalitis, mitochondrial damage is observed; however, this damage is mitigated by the activation of mitophagy via the PINK1/PARKIN pathway. This regulatory feedback mechanism facilitates the removal of damaged mitochondria, prevents neuronal apoptosis, and consequently safeguards neural tissue. ART activates the PINK1/PARKIN pathway to enhance mitophagy, thereby exerting neuroprotective effects and may achieve therapeutic goals in treating anti-NMDAR encephalitis.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Artesunato , Modelos Animales de Enfermedad , Fármacos Neuroprotectores , Proteínas Quinasas , Animales , Artesunato/farmacología , Artesunato/uso terapéutico , Ratones , Femenino , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Encefalitis Antirreceptor N-Metil-D-Aspartato/patología , Encefalitis Antirreceptor N-Metil-D-Aspartato/tratamiento farmacológico , Proteínas Quinasas/metabolismo , Neuronas/efectos de los fármacos , Neuronas/patología , Neuronas/metabolismo , Microscopía Electrónica de Transmisión , Mitofagia/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Hipocampo/patología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo
9.
J Vis Exp ; (207)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38767370

RESUMEN

Preclinical gene therapy research, particularly in rodent and large animal models, necessitates the production of AAV vectors with high yield and purity. Traditional approaches in research laboratories often involve extensive use of cell culture dishes to cultivate HEK293T cells, a process that can be both laborious and problematic. Here, a unique in-house method is presented, which simplifies this process with a specific cell factory (or cell stacks, CF10) platform. An integration of polyethylene glycol/aqueous two-phase partitioning with iodixanol gradient ultracentrifugation improves both the yield and purity of the generated AAV vectors. The purity of the AAV vectors is verified through SDS-PAGE and silver staining, while the ratio of full to empty particles is determined using transmission electron microscopy (TEM). This approach offers an efficient cell factory platform for the production of AAV vectors at high yields, coupled with an improved purification method to meet the quality demands for in vivo studies.


Asunto(s)
Dependovirus , Vectores Genéticos , Dependovirus/genética , Humanos , Vectores Genéticos/química , Células HEK293 , Ácidos Triyodobenzoicos/química , Polietilenglicoles/química , Microscopía Electrónica de Transmisión
10.
Arthritis Res Ther ; 26(1): 102, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778407

RESUMEN

BACKGROUND: To perform a detailed morphological analysis of the inorganic portion of two different clinical presentations of calcium-based deposits retrieved from subjects with SSc and identify a chemical dissolution of these deposits suitable for clinical use. METHODS: Chemical analysis using Fourier Transform IR spectroscopy ('FTIR'), Raman microscopy, Powder X-Ray Diffraction ('PXRD'), and Transmission Electron Microscopy ('TEM') was undertaken of two distinct types of calcinosis deposits: paste and stone. Calcinosis sample titration with ethylenediaminetetraacetic acid ('EDTA') assessed the concentration at which the EDTA dissolved the calcinosis deposits in vitro. RESULTS: FTIR spectra of the samples displayed peaks characteristic of hydroxyapatite, where signals attributable to the phosphate and carbonate ions were all identified. Polymorph characterization using Raman spectra were identical to a hydroxyapatite reference while the PXRD and electron diffraction patterns conclusively identified the mineral present as hydroxyapatite. TEM analysis showed differences of morphology between the samples. Rounded particles from stone samples were up to a few micron in size, while needle-like crystals from paste samples reached up to 0.5 µm in length. Calcium phosphate deposits were effectively dissolved with 3% aqueous solutions of EDTA, in vitro. Complete dissolution of both types of deposit was achieved in approximately 30 min using a molar ratio of EDTA/HAp of ≈ 300. CONCLUSIONS: Stone and paste calcium-based deposits both comprise hydroxyapatite, but the constituent crystals vary in size and morphology. Hydroxyapatite is the only crystalline polymorph present in the SSc-related calcinosis deposits. Hydroxyapatite can be dissolved in vitro using a dosage of EDTA considered safe for clinical application. Further research is required to establish the optimal medium to develop the medical product, determine the protocol for clinical application, and to assess the effectiveness of EDTA for local treatment of dystrophic calcinosis.


Asunto(s)
Calcinosis , Ácido Edético , Ácido Edético/química , Humanos , Calcinosis/tratamiento farmacológico , Calcinosis/patología , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Microscopía Electrónica de Transmisión/métodos , Difracción de Rayos X/métodos , Espectrometría Raman/métodos , Femenino , Durapatita/química , Persona de Mediana Edad , Masculino , Quelantes del Calcio/química
11.
J Helminthol ; 98: e40, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738533

RESUMEN

In the past decade, interest has significantly increased regarding the medicinal and nutritional benefits of pomegranate (Punica granatum) peel. This study examined the effects of using pomegranate peel extract (PGE) alone and in combination with albendazole (ABZ) on ultrastructural and immunological changes in cystic echinococcosis in laboratory-infected mice. Results revealed that the smallest hydatid cyst size and weight (0.48 ± 0.47mm, 0.17 ± 0.18 gm) with the highest drug efficacy (56.2%) was detected in the PGE + ABZ group, which also exhibited marked histopathological improvement. Ultrastructural changes recorded by transmission electron microscopy including fragmentation of the nucleus, glycogen depletion, and multiple lysosomes in vacuolated cytoplasm were more often observed in PGE + ABZ group. IFN-γ levels were significantly increased in the group treated with ABZ, with a notable reduction following PGE treatment, whether administered alone or in combination with ABZ. Thus, PGE enhanced the therapeutic efficiency of ABZ, with improvement in histopathological and ultrastructural changes.


Asunto(s)
Albendazol , Equinococosis , Extractos Vegetales , Granada (Fruta) , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/administración & dosificación , Granada (Fruta)/química , Ratones , Equinococosis/tratamiento farmacológico , Equinococosis/parasitología , Albendazol/farmacología , Albendazol/administración & dosificación , Antihelmínticos/farmacología , Antihelmínticos/administración & dosificación , Modelos Animales de Enfermedad , Microscopía Electrónica de Transmisión , Interferón gamma/sangre , Femenino , Masculino
12.
Methods Mol Biol ; 2800: 75-87, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38709479

RESUMEN

Enzymatic ascorbate peroxidase (APEX) tagging allows for high-resolution, three-dimensional protein distribution analyses in cells and tissues. This chapter describes the application of APEX-tagging to visualize the trafficking of the epidermal growth factor receptor (EGFR) during epidermal growth factor-mediated receptor activation. Here, we describe the preparation of cells, methods to validate the stimulation of the EGFR, and visualization of the APEX-resolved distribution of the EGFR in the transmission electron microscope.


Asunto(s)
Receptores ErbB , Microscopía Electrónica de Transmisión , Transporte de Proteínas , Humanos , Ascorbato Peroxidasas/química , Ascorbato Peroxidasas/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Microscopía Electrónica de Transmisión/métodos
13.
Aquat Toxicol ; 272: 106961, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38781688

RESUMEN

In recent years, the intensive production of nanoparticles with a wide application has led to their transfer to the environment, including the water ecosystem. The accumulation of nanoparticles in fish, causing various pathological changes in the host, raises certain concerns. In the current study, we investigated the penetration and bioaccumulation of Fe3O4 nanoparticles, in the liver of common carp (Cyprinus carpio Linnaeus, 1758). Common carp juveniles were exposed to Fe3O4 nanoparticles at concentrations of 10 and 100 mg. After 7 days, their livers were examined by light and transmission electron microscopes. Compared to normal fish's liver, after using a small concentration (10 mg) of nanoparticles, changes were observed in erythrocytes, hepatocytes, intracellular canaliculi, and bile ducts of the liver. At a high concentration (100 mg), the intensity of changes increased significantly. The liver's capsule was damaged, and a considerable number of hepatocytes were completely destroyed. Additionally, the walls of blood vessels and biliary ductule walls was notably disturbed. It was found that the intensity of pathologies occurring in the liver, increases proportionally with higher concentrations of nanoparticles. Confirmation via electron microscopic methods revealed that Fe3O4 nanoparticles, when administered with food to common carp, enter the fish's liver through erythrocytes localized in the lumen of blood vessels. From there, they traverse through the endothelium of vessels, proceed to hepatocytes, including cytoplasmic organelles, intracellular canaliculi, biliary ductules, and eventually reach the bile ducts. Fe3O4 nanoparticles in all structural elements of fish liver was up to 20 nm. Therefore, high concentrations of nanoparticles in the environment harms the bodies of aquatic organisms, including fish. The changes identified in the liver of common carp in the present study are valuable information in assessing possible risks to other components of the aquatic ecosystem and organisms.


Asunto(s)
Carpas , Hígado , Contaminantes Químicos del Agua , Animales , Carpas/metabolismo , Hígado/metabolismo , Hígado/efectos de los fármacos , Hígado/ultraestructura , Contaminantes Químicos del Agua/toxicidad , Microscopía Electrónica de Transmisión , Nanopartículas Magnéticas de Óxido de Hierro/toxicidad
14.
Micron ; 183: 103660, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38820862

RESUMEN

Tardigrades are invertebrates known to science for over 250 years. Although the ability of some species of tardigrades to form cysts has been reported, little is known about the encystment and internal organisation of the cysts. During cyst formation, contraction of the body affects the internal organs' morphology. The organs are compressed and have a compact appearance. The organisation of the digestive system, associated structures, and the reproductive system are analysed in cysts on indefinite and well-defined encystment periods - up to eleven months. The digestive system of encysted animals was organised into three main parts - a foregut, a midgut, and a hindgut. The presence of digestive system-associated structures, such as buccal glands or muscles, was noted and described. The excretory organs, called Malpighian tubules, open into the zone between the midgut and the hindgut. Furthermore, the oviduct opens into the hindgut. The first analysis of the reproductive system of cysts at the ultrastructural level is presented here, revealing interesting and undescribed aspects related to the physiology. Besides the anatomical and histological examination, the morphology and changes that occur during cyst formation are described.


Asunto(s)
Sistema Digestivo , Tardigrada , Animales , Tardigrada/fisiología , Sistema Digestivo/ultraestructura , Sistema Digestivo/anatomía & histología , Genitales/anatomía & histología , Genitales/ultraestructura , Agua Dulce , Microscopía Electrónica de Transmisión , Femenino
15.
ACS Synth Biol ; 13(6): 1842-1850, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38729919

RESUMEN

In-cell self-assembly of natural viral capsids is an event that can be visualized under transmission electron microscopy (TEM) observations. By mimicking the self-assembly of natural viral capsids, various artificial protein- and peptide-based nanocages were developed; however, few studies have reported the in-cell self-assembly of such nanocages. Our group developed a ß-Annulus peptide that can form a nanocage called artificial viral capsid in vitro, but in-cell self-assembly of the capsid has not been achieved. Here, we designed an artificial viral capsid decorated with a fluorescent protein, StayGold, to visualize in-cell self-assembly. Fluorescence anisotropy measurements and fluorescence resonance energy transfer imaging, in addition to TEM observations of the cells and super-resolution microscopy, revealed that StayGold-conjugated ß-Annulus peptides self-assembled into the StayGold-decorated artificial viral capsid in a cell. Using these techniques, we achieved the in-cell self-assembly of an artificial viral capsid.


Asunto(s)
Proteínas de la Cápside , Cápside , Transferencia Resonante de Energía de Fluorescencia , Péptidos , Péptidos/química , Cápside/química , Cápside/metabolismo , Proteínas de la Cápside/química , Proteínas de la Cápside/metabolismo , Proteínas de la Cápside/genética , Proteínas Luminiscentes/química , Proteínas Luminiscentes/metabolismo , Proteínas Luminiscentes/genética , Microscopía Electrónica de Transmisión , Polarización de Fluorescencia , Ensamble de Virus
16.
Mikrochim Acta ; 191(6): 326, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740583

RESUMEN

Migration is an initial step in tumor expansion and metastasis; suppressing cellular migration is beneficial to cancer therapy. Herein, we designed a novel biogated nanoagents that integrated the migration inhibitory factor into the mesoporous silica nanoparticle (MSN) drug delivery nanosystem to realize cell migratory inhibition and synergistic treatment. Antisense oligonucleotides (Anti) of microRNA-330-3p, which is positively related with cancer cell proliferation, migration, invasion, and angiogenesis, not only acted as the locker for blocking drugs but also acted as the inhibitory factor for suppressing migration via gene therapy. Synergistic with gene therapy, the biogated nanoagents (termed as MSNs-Gef-Anti) could achieve on-demand drug release based on the intracellular stimulus-recognition and effectively kill tumor cells. Experimental results synchronously demonstrated that the migration suppression ability of MSNs-Gef-Anti nanoagents (nearly 30%) significantly contributed to cancer therapy, and the lethality rate of the non-small-cell lung cancer was up to 70%. This strategy opens avenues for realizing efficacious cancer therapy and should provide an innovative way for pursuing the rational design of advanced nano-therapeutic platforms with the combination of cancer cell migratory inhibition.


Asunto(s)
Movimiento Celular , Quimioterapia Combinada , Nanopartículas , Neoplasias , Dióxido de Silicio , Movimiento Celular/efectos de los fármacos , Dióxido de Silicio/química , Quimioterapia Combinada/métodos , Neoplasias/tratamiento farmacológico , Sistema de Administración de Fármacos con Nanopartículas/química , Sistema de Administración de Fármacos con Nanopartículas/uso terapéutico , Nanopartículas/química , Nanopartículas/uso terapéutico , Nanopartículas/ultraestructura , Células A549 , Microscopía Electrónica de Transmisión , Humanos
17.
Microsc Microanal ; 30(3): 539-551, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38758132

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease of unknown origin with limited treatment options and poor prognosis. The encouraging findings from preclinical investigations utilizing mesenchymal stem cells (MSCs) indicated that they could serve as a promising therapeutic alternative for managing chronic lung conditions, such as IPF. The objective of this study was to compare the efficiency of bone marrow-derived MSCs (BM-MSCs) versus prednisolone, the standard anti-inflammatory medication, in rats with bleomycin (BLM)-induced lung fibrosis. Four groups were created: a control group, a BLM group, a prednisolone-treated group, and a BM-MSCs-treated group. To induce lung fibrosis, 5 mg/kg of BLM was administered intratracheally. BLM significantly increased serum levels of pro-inflammatory cytokines and oxidative stress markers. The disturbed lung structure was also revealed by light and transmission electron microscopic studies. Upregulation in the immune expression of alpha-smooth muscle actin, transforming growth factor beta-1, and Bax was demonstrated. Interestingly, all findings significantly regressed on treatment with prednisolone and BM-MSCs. However, treatment with BM-MSCs showed better results than with prednisolone. In conclusion, BM-MSCs could be a promising approach for managing lung fibrosis.


Asunto(s)
Bleomicina , Modelos Animales de Enfermedad , Células Madre Mesenquimatosas , Prednisolona , Fibrosis Pulmonar , Animales , Prednisolona/uso terapéutico , Prednisolona/farmacología , Ratas , Fibrosis Pulmonar/terapia , Fibrosis Pulmonar/patología , Pulmón/patología , Inmunohistoquímica , Masculino , Citocinas/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Trasplante de Células Madre Mesenquimatosas/métodos , Histocitoquímica , Células de la Médula Ósea , Microscopía Electrónica de Transmisión
18.
J Anat ; 245(2): 271-288, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38613211

RESUMEN

Auditory sensitivity and frequency resolution depend on the optimal transfer of sound-induced vibrations from the basilar membrane (BM) to the inner hair cells (IHCs), the principal auditory receptors. There remains a paucity of information on how this is accomplished along the frequency range in the human cochlea. Most of the current knowledge is derived either from animal experiments or human tissue processed after death, offering limited structural preservation and optical resolution. In our study, we analyzed the cytoarchitecture of the human cochlear partition at different frequency locations using high-resolution microscopy of uniquely preserved normal human tissue. The results may have clinical implications and increase our understanding of how frequency-dependent acoustic vibrations are carried to human IHCs. A 1-micron-thick plastic-embedded section (mid-modiolar) from a normal human cochlea uniquely preserved at lateral skull base surgery was analyzed using light and transmission electron microscopy (LM, TEM). Frequency locations were estimated using synchrotron radiation phase-contrast imaging (SR-PCI). Archival human tissue prepared for scanning electron microscopy (SEM) and super-resolution structured illumination microscopy (SR-SIM) were also used and compared in this study. Microscopy demonstrated great variations in the dimension and architecture of the human cochlear partition along the frequency range. Pillar cell geometry was closely regulated and depended on the reticular lamina slope and tympanic lip angle. A type II collagen-expressing lamina extended medially from the tympanic lip under the inner sulcus, here named "accessory basilar membrane." It was linked to the tympanic lip and inner pillar foot, and it may contribute to the overall compliance of the cochlear partition. Based on the findings, we speculate on the remarkable microanatomic inflections and geometric relationships which relay different sound-induced vibrations to the IHCs, including their relevance for the evolution of human speech reception and electric stimulation with auditory implants. The inner pillar transcellular microtubule/actin system's role of directly converting vibration energy to the IHC cuticular plate and ciliary bundle is highlighted.


Asunto(s)
Cóclea , Órgano Espiral , Humanos , Cóclea/anatomía & histología , Cóclea/fisiología , Órgano Espiral/anatomía & histología , Órgano Espiral/fisiología , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Transducción de Señal/fisiología , Membrana Basilar/anatomía & histología , Membrana Basilar/fisiología
19.
J Hazard Mater ; 471: 134253, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38642497

RESUMEN

Micro- and nanoplastics (MNPs) are ubiquitous in the environment, resulting in the uptake of MNPs by a variety of organisms, including humans, leading to particle-cell interaction. Human macrophages derived from THP-1 cell lines take up Polystyrene (PS), a widespread plastic. The question therefore arises whether primary human macrophages also take up PS micro- and nanobeads (MNBs) and how they react to this stimulation. Major aim of this study is to visualize this uptake and to validate the isolation of macrophages from peripheral blood mononuclear cells (PBMCs) to assess the impact of MNPs on human macrophages. Uptake of macrophages from THP-1 cell lines and PBMCs was examined by transmission electron microscopy (TEM), scanning electron microscopy and live cell imaging. In addition, the reaction of the macrophages was analyzed in terms of metabolic activity, cytotoxicity, production of reactive oxygen species (ROS) and macrophage polarization. This study is the first to visualize PS MNBs in primary human cells using TEM and live cell imaging. Metabolic activity was size- and concentration-dependent, necrosis and ROS were increased. The methods demonstrated in this study outline an approach to assess the influence of MNP exposure on human macrophages and help investigating the consequences of worldwide plastic pollution.


Asunto(s)
Macrófagos , Microplásticos , Poliestirenos , Especies Reactivas de Oxígeno , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Poliestirenos/química , Poliestirenos/toxicidad , Células THP-1 , Microplásticos/toxicidad , Leucocitos Mononucleares/efectos de los fármacos , Nanopartículas/toxicidad , Nanopartículas/química , Supervivencia Celular/efectos de los fármacos , Microscopía Electrónica de Transmisión , Tamaño de la Partícula
20.
Exp Parasitol ; 261: 108765, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38679126

RESUMEN

Toxocara is a genus of nematodes, which infects a variety of hosts, principally dogs and cats, with potential zoonotic risks to humans. Toxocara spp. larvae are capable of migrating throughout the host tissues, eliciting eosinophilic and granulomatous reactions, while surviving for extended periods of time, unchanged, in the host. It is postulated that larvae are capable of altering the host's immune response through the release of excretory-secretory products, containing both proteins and extracellular vesicles (EVs). The study of EVs has increased exponentially in recent years, largely due to their potential use as a diagnostic tool, and in molecular therapy. To this end, there have been multiple isolation methods described for the study of EVs. Here, we use nanoparticle tracking to compare the yield, size distribution, and % labelling of EV samples acquired through various reported methods, from larval cultures of Toxocara canis and T. cati containing Toxocara excretory-secretory products (TES). The methods tested include ultracentrifugation, polymer precipitation, magnetic immunoprecipitation, size exclusion chromatography, and ultrafiltration. Based on these findings, ultrafiltration produces the best results in terms of yield, expected particle size, and % labelling of sample. Transmission electron microscopy confirmed the presence of EVs with characteristic cup-shaped morphology. These findings can serve as a guide for those investigating EVs, particularly those released from multicellular organisms, such as helminths, for which few comparative analyses have been performed.


Asunto(s)
Cromatografía en Gel , Exosomas , Vesículas Extracelulares , Microscopía Electrónica de Transmisión , Toxocara canis , Toxocara , Ultracentrifugación , Animales , Toxocara/aislamiento & purificación , Toxocara/metabolismo , Toxocara/química , Toxocara canis/química , Exosomas/química , Exosomas/ultraestructura , Exosomas/metabolismo , Vesículas Extracelulares/química , Vesículas Extracelulares/ultraestructura , Vesículas Extracelulares/metabolismo , Perros , Larva , Inmunoprecipitación , Toxocariasis/parasitología , Gatos , Nanopartículas/química , Tamaño de la Partícula , Proteínas del Helminto/análisis , Proteínas del Helminto/metabolismo , Proteínas del Helminto/química , Proteínas del Helminto/aislamiento & purificación
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