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1.
Neoplasma ; 71(2): 153-163, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38766856

RESUMEN

Skin cancer is one of the most common malignancies in white populations. The therapy strategy is important in skin cancer treatment, depending on several criteria such as stage, size, and localization. Removal of cancerous tissue following anticancer therapeutic administration is considered as gold standard in skin cancer treatment. However, annually rising drug resistance, local inflammation, and ineffective treatment result in a reduction in the effectiveness of the patient's treatment. Nanotechnology has emerged as a prospective in the field of skin cancer medicine, offering innovative, promising solutions for therapeutic procedures and targeted drug delivery. Different nanomaterials are investigated for their potential in skin cancer treatment. Nanohydrogels as a hybrid material, have gained considerable attention due to their unique biomedical and pharmaceutical properties, such as biocompatibility, high water content, and tunable physicochemical characteristics. The principal problem with common skin melanoma chemotherapy is the strong side effects because therapeutics used for treatment do not distinguish cancer cells from healthy cells. Nanohydrogels, as a new-generation, versatile system with the possession of dual characteristics of hydrogels and nanoparticles have shown great potential in targeted delivery in cancer therapy thanks to the possibility of their various modifications, and by that overcome problems with side effects of treatment. This scientific review provides an analysis of the current state of research on nanohydrogels in skin cancer medicine, highlighting their design principles, synthesis methods, and applications in drug delivery, imaging, and combination therapies.


Asunto(s)
Hidrogeles , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/tratamiento farmacológico , Hidrogeles/química , Sistemas de Liberación de Medicamentos , Nanocompuestos/uso terapéutico , Nanocompuestos/química , Antineoplásicos/uso terapéutico
2.
Cell Biol Toxicol ; 39(5): 1939-1956, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-34973136

RESUMEN

The unique physicochemical properties make inorganic nanoparticles (INPs) an exciting tool in diagnosis and disease management. However, as INPs are relatively difficult to fully degrade and excrete, their unintended accumulation in the tissue might result in adverse health effects. Herein, we provide a methylome-transcriptome framework for chronic effects of INPs, commonly used in biomedical applications, in human kidney TH-1 cells. Renal clearance is one of the most important routes of nanoparticle excretion; therefore, a detailed evaluation of nanoparticle-mediated nephrotoxicity is an important task. Integrated analysis of methylome and transcriptome changes induced by INPs (PEG-AuNPs, Fe3O4NPs, SiO2NPs, and TiO2NPs) revealed significantly deregulated genes with functional classification in immune response, DNA damage, and cancer-related pathways. Although most deregulated genes were unique to individual INPs, a relatively high proportion of them encoded the transcription factors. Interestingly, FOS hypermethylation inversely correlating with gene expression was associated with all INPs exposures. Our study emphasizes the need for a more comprehensive investigation of INPs' biological safety, especially after chronic exposure.


Asunto(s)
Nanopartículas del Metal , Transcriptoma , Humanos , Transcriptoma/genética , Epigenoma/genética , Oro , Nanopartículas del Metal/toxicidad , Metilación de ADN/genética , Riñón
3.
Prague Med Rep ; 117(1): 18-33, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26995200

RESUMEN

Numerous diagnostic tests are used to evaluate the hypothalamic-pituitary-adrenal axis (HPA axis). The gold standard is still considered the insulin tolerance test (ITT), but this test has many limitations. Current guidelines therefore recommend the Synacthen test first when an HPA axis insufficiency is suspected. However, the dose of Synacthen that is diagnostically most accurate and sensitive is still a matter of debate. We investigated 15 healthy men with mean/median age 27.4/26 (SD±4.8) years, and mean/median BMI (body mass index) 25.38/24.82 (SD±3.2) kg/m2. All subjects underwent 4 dynamic tests of the HPA axis, specifically 1 µg, 10 µg, and 250 µg Synacthen (ACTH) tests and an ITT. Salivary cortisol, cortisone, pregnenolone, and DHEA (dehydroepiandrosterone) were analysed using liquid chromatography-tandem mass spectrometry. During the ITT maximum salivary cortisol levels over 12.5 nmol/l were found at 60 minutes. Maximum cortisol levels in all of the Synacthen tests were higher than this; however, demonstrating that sufficient stimulation of the adrenal glands was achieved. Cortisone reacted similarly as cortisol, i.e. we did not find any change in the ratio of cortisol to cortisone. Pregnenolone and DHEA were higher during the ITT, and their peaks preceded the cortisol peak. There was no increase of pregnenolone or DHEA in any of the Synacthen tests. We demonstrate that the 10 µg Synacthen dose is sufficient stimulus for testing the HPA axis and is also a safe and cost-effective alternative. This dose also largely eliminates both false negative and false positive results.


Asunto(s)
Insuficiencia Suprarrenal/diagnóstico , Cosintropina/farmacología , Deshidroepiandrosterona/análisis , Hidrocortisona/análisis , Pregnenolona/análisis , Saliva/metabolismo , Insuficiencia Suprarrenal/metabolismo , Adulto , Cromatografía Liquida/métodos , Pruebas Diagnósticas de Rutina/métodos , Voluntarios Sanos , Hormonas/farmacología , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Sistema Hipófiso-Suprarrenal/metabolismo
4.
Prague Med Rep ; 117(2-3): 98-107, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27668526

RESUMEN

Studies on the time course of ACTH- or insulin-induced hypoglycemia stimulating adrenal androgens are usually limited to dehydroepiandrosterone and/or its sulphate. Our data on dehydroepiandrosterone (DHEA) and its hydroxylated metabolites clearly show that measurements of DHEA and its sulphate (DHEAS) are valuable markers of the integrity of the HPA (hypothalamus-pituitary-adrenal) axis. Assessments of HPA function should rely on measurements of baseline and/or stimulated serum cortisol concentrations, and C19 Δ5-steroids may provide additional information. The art of stimulation of 7- and 16-hydroxylated metabolites of DHEA can help our understanding of the formation sequence of these compounds.


Asunto(s)
Adenoma Hipofisario Secretor de ACTH/diagnóstico , Insuficiencia Suprarrenal/diagnóstico , Sulfato de Deshidroepiandrosterona/sangre , Hidrocortisona/sangre , Adenoma Hipofisario Secretor de ACTH/sangre , Insuficiencia Suprarrenal/sangre , Adulto , Deshidroepiandrosterona/administración & dosificación , Técnicas de Diagnóstico Endocrino , Femenino , Humanos , Hipoglucemia/inducido químicamente , Persona de Mediana Edad
5.
Prague Med Rep ; 116(1): 40-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25923969

RESUMEN

Eight women of reproductive age with normal body mass index were given 5 standardised meals, and their hormonal milieu was determined during the course of the day. Plasma from 12 withdrawals was analysed for dehydroepiandrosterone and its 7- and 16-hydroxylated metabolites. Overall, there was a maximum in the levels of steroid hormones in the morning, followed by decreases throughout the day. There was also an additional significant decrease found for dehydroepiandrosterone and its 7α-hydroxyderivative in association with the consumption of main meals, but not for the 7ß-isomer or 16α-hydroxyderivative.


Asunto(s)
Deshidroepiandrosterona/farmacocinética , Ingestión de Alimentos/efectos de los fármacos , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/farmacocinética , Adulto , Deshidroepiandrosterona/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Hidroxilación
6.
Proc Natl Acad Sci U S A ; 108(33): 13552-7, 2011 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-21808006

RESUMEN

The regulation and the dynamics of membrane trafficking events have been studied primarily in in vitro models that often do not fully reflect the functional complexity found in a living multicellular organism. Here we used intravital microscopy in the salivary glands of live rodents to investigate regulated exocytosis, a fundamental process in all of the secretory organs. We found that ß-adrenergic stimulation elicits exocytosis of large secretory granules, which gradually collapse with the apical plasma membrane without any evidence of compound exocytosis, as was previously described. Furthermore, we show that the driving force required to complete the collapse of the granules is provided by the recruitment of F-actin and nonmuscle myosin II on the granule membranes that is triggered upon fusion with the plasma membrane. Our results provide information on the machinery controlling regulated secretion and show that intravital microscopy provides unique opportunities to address fundamental questions in cell biology under physiological conditions.


Asunto(s)
Actomiosina/fisiología , Exocitosis , Microscopía Confocal , Actinas/metabolismo , Agonistas Adrenérgicos beta/farmacología , Animales , Membrana Celular , Polaridad Celular , Exocitosis/efectos de los fármacos , Ratones , Ratones Transgénicos , Miosina Tipo IIA no Muscular , Transporte de Proteínas , Glándulas Salivales , Vesículas Secretoras/metabolismo
7.
EFSA J ; 22(7): e8939, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39050025

RESUMEN

The food enzyme thermolysin (EC. 3.4.24.27) is produced with the non-genetically modified Anoxybacillus caldiproteolyticus strain AE-TP by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in eight food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of seven food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.989 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (700 mg TOS/kg bw per day, the mid-dose tested), the Panel derived a revised margin of exposure of at least 708. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

8.
EFSA J ; 22(7): e8940, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39050021

RESUMEN

The food enzyme oryzin (EC 3.4.21.63) is produced with the non-genetically modified Aspergillus ochraceus strain AE-P by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in nine food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two food processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eight food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.354 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1862 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 5260. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

9.
EFSA J ; 22(7): e8936, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39040571

RESUMEN

The food enzyme lysophospholipase (2-lysophosphatidylcholine acylhydrolase, EC 3.1.1.5) is produced with the genetically modified Trichoderma reesei strain DP-Nyc81 by Genencor International B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for the production of glucose syrups and other starch hydrolysates. Since residual amounts of food enzyme-total organic solids are removed during these food manufacturing processes, dietary exposure was not calculated and toxicological studies were considered unnecessary. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

10.
EFSA J ; 22(7): e8944, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39050023

RESUMEN

The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Rhizopus arrhizus strain AE-TL(B) by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in two food manufacturing processes. Subsequently, the applicant requested to extend its use to include four additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of six food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining five processes. Dietary exposure was calculated to be up to 0.086 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1960 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 22,791. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

11.
EFSA J ; 22(8): e8935, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39104807

RESUMEN

The food enzyme glucan 1,4-α-maltohydrolase (4-α-d-glucan α-maltohydrolase; EC 3.2.1.133) is produced with the genetically modified Saccharomyces cerevisiae strain LALL-MA+ by Danstar Ferment AG. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for production of baked products. Dietary exposure was estimated to be up to 0.014 mg TOS/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme manufacturing process, toxicity tests were considered unnecessary by the Panel. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and four matches were found, three with respiratory allergens and one with an allergen from mosquito (injected). The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

12.
EFSA J ; 22(8): e8949, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39114322

RESUMEN

The food enzyme ß-galactosidase (ß-d-galactoside galactohydrolase; EC 3.2.1.23) is produced with the genetically modified Bacillus licheniformis strain DSM 34099 by Kerry Group Services International, Ltd. (KGSI). The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. The production strain met the requirements for the qualified presumption of safety (QPS) approach. The food enzyme is intended to be used in two food manufacturing processes. Dietary exposure was estimated to be up to 7.263 mg total organic solids/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme manufacturing process, toxicity tests, other than an assessment of allergenicity, were considered unnecessary by the Panel. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and one match with a food allergen from kiwi fruit was found. The Panel considered that a risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to kiwi fruit, cannot be excluded. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

13.
EFSA J ; 22(7): e8948, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39086456

RESUMEN

The food enzyme α-amylase (4-α-d-glucan glucanohydrolase i.e. EC 3.2.1.1) is produced with the non-genetically modified Cellulosimicrobium funkei strain AE-AMT by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that the food enzyme did not give rise to safety concerns when used in seven food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of ten food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining nine processes. The dietary exposure was calculated to be up to 0.049 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (230 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 4694. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

14.
EFSA J ; 22(7): e8947, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39086457

RESUMEN

The food enzyme pullulanase (pullulan 6-α-glucanohydrolase; EC 3.2.1.41) is produced with the non-genetically modified Pullulanibacillus naganoensis strain AE-PL by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in one food manufacturing process. Subsequently, the applicant has requested to extend its use to include seven additional processes and to revise the previous use level. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eight food manufacturing processes. As the food enzyme-total organic solids (TOS) are not carried into the final foods in two food manufacturing processes, the dietary exposure was estimated only for the remaining six processes. The dietary exposure was calculated to be up to 0.004 mg TOS/kg body weight (bw) per day in European populations. The Panel evaluated the repeated dose 90-day oral toxicity study in rats submitted in the previous application and identified a no observed adverse effect level of 643 mg TOS/kg bw per day, the highest dose tested. When compared with the calculated dietary exposure, this resulted in a margin of exposure of at least 160,750. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

15.
EFSA J ; 22(7): e8945, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39086455

RESUMEN

The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Aspergillus luchuensis strain AE-L by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in one food manufacturing process. Subsequently, the applicant has requested to extend its use to include four additional processes and to revise the previous use level. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of five food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.458 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (1726 mg TOS/kg bw per day, the highest dose tested), the Panel derived a revised margin of exposure of at least 3769. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

16.
Bioelectrochemistry ; 153: 108467, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37244203

RESUMEN

This study compares the performance and output of an electrochemical phospholipid membrane platform against respective in vitro cell-based toxicity testing methods using three toxicants of different biological action (chlorpromazine (CPZ), colchicine (COL) and methyl methanesulphonate (MMS)). Human cell lines from seven different tissues (lung, liver, kidney, placenta, intestine, immune system) were used to validate this physicochemical testing system. For the cell-based systems, the effective concentration at 50 % cell death (EC50) values are calculated. For the membrane sensor, a limit of detection (LoD) value was extracted as a quantitative parameter describing the minimum concentration of toxicant which significantly affects the structure of the phospholipid sensor membrane layer. LoD values were found to align well with the EC50 values when acute cell viability was used as an end-point and showed a similar toxicity ranking of the tested toxicants. Using the colony forming efficiency (CFE) or DNA damage as end-point, a different order of toxicity ranking was observed. The results of this study showed that the electrochemical membrane sensor generates a parameter relating to biomembrane damage, which is the predominant factor in decreasing cell viability when in vitro models are acutely exposed to toxicants. These results lead the way to using electrochemical membrane-based sensors for rapid relevant preliminary toxicity screens.


Asunto(s)
Hígado , Pruebas de Toxicidad , Humanos , Línea Celular , Pruebas de Toxicidad/métodos , Clorpromazina , Sustancias Peligrosas , Fosfolípidos
17.
Histochem Cell Biol ; 138(2): 201-13, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22544351

RESUMEN

Non-viral-mediated gene delivery represents an alternative way to express the gene of interest without inducing immune responses or other adverse effects. Understanding the mechanisms by which plasmid DNAs are delivered to the proper target in vivo is a fundamental issue that needs to be addressed in order to design more effective strategies for gene therapy. As a model system, we have used the submandibular salivary glands in live rats and we have recently shown that reporter transgenes can be expressed in different cell populations of the glandular epithelium, depending on the modality of administration of plasmid DNA. Here, by using a combination of immunofluorescence and intravital microscopy, we have explored the relationship between the pattern of transgenes expression and the internalization of plasmid DNA. We found that plasmid DNA is internalized: (1) by all the cells in the salivary gland epithelium, when administered alone, (2) by large ducts, when mixed with empty adenoviral particles, and (3) by acinar cells upon stimulation of compensatory endocytosis. Moreover, we showed that plasmid DNA utilizes different routes of internalization, and evades both the lysosomal degradative pathway and the retrograde pathway towards the Golgi apparatus. This study clearly shows that in vivo approaches have the potential to address fundamental questions on the cellular mechanisms regulating gene delivery.


Asunto(s)
Membrana Celular/metabolismo , ADN/metabolismo , Glándulas Salivales/metabolismo , Células Acinares , Adenoviridae/genética , Animales , Endocitosis , Epitelio/metabolismo , Técnicas de Transferencia de Gen , Vectores Genéticos , Masculino , Plásmidos , Ratas , Ratas Sprague-Dawley , Glándula Submandibular/metabolismo , Transgenes
18.
Nanomaterials (Basel) ; 12(3)2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35159859

RESUMEN

Data suitable for assembling a physiologically-based pharmacokinetic (PBPK) model for nanoparticles (NPs) remain relatively scarce. Therefore, there is a trend in extrapolating the results of in vitro and in silico studies to in vivo nanoparticle hazard and risk assessment. To evaluate the reliability of such approach, a pharmacokinetic study was performed using the same polyethylene glycol-coated gold nanoparticles (PEG-AuNPs) in vitro and in vivo. As in vitro models, human cell lines TH1, A549, Hep G2, and 16HBE were employed. The in vivo PEG-AuNP biodistribution was assessed in rats. The internalization and exclusion of PEG-AuNPs in vitro were modeled as first-order rate processes with the partition coefficient describing the equilibrium distribution. The pharmacokinetic parameters were obtained by fitting the model to the in vitro data and subsequently used for PBPK simulation in vivo. Notable differences were observed in the internalized amount of Au in individual cell lines compared to the corresponding tissues in vivo, with the highest found for renal TH1 cells and kidneys. The main reason for these discrepancies is the absence of natural barriers in the in vitro conditions. Therefore, caution should be exercised when extrapolating in vitro data to predict the in vivo NP burden and response to exposure.

19.
Nanomaterials (Basel) ; 11(7)2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34203551

RESUMEN

Despite the obvious advantages of gold nanoparticles for biomedical applications, controversial and incomplete toxicological data hamper their widespread use. Here, we present the results from an in vivo toxicity study using gold nanoparticles coated with polyethylene glycol (PEG-AuNPs). The pharmacokinetics and biodistribution of PEG-AuNPs were examined in the rat's liver, lung, spleen, and kidney after a single i.v. injection (0.7 mg/kg) at different time intervals. PEG-AuNPs had a relatively long blood circulation time and accumulated primarily in the liver and spleen, where they remained for up to 28 days after administration. Increased cytoplasmic vacuolation in hepatocytes 24 h and 7 days after PEG-AuNPs exposure and apoptotic-like cells in white splenic pulp 24 h after administration has been detected, however, 28 days post-exposure were no longer observed. In contrast, at this time point, we identified significant changes in lipid metabolism, altered levels of liver injury markers, and elevated monocyte count, but without marked biological relevance. In blood cells, no DNA damage was present in any of the studied time intervals, with the exception of DNA breakage transiently detected in primary kidney cells 4 h post-injection. Our results indicate that the tissue accumulation of PEG-AuNPs might result in late toxic effects.

20.
Histochem Cell Biol ; 133(5): 481-91, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20372919

RESUMEN

Intravital microscopy encompasses various optical microscopy techniques aimed at visualizing biological processes in live animals. In the last decade, the development of non-linear optical microscopy resulted in an enormous increase of in vivo studies, which have addressed key biological questions in fields such as neurobiology, immunology and tumor biology. Recently, few studies have shown that subcellular processes can be imaged dynamically in the live animal at a resolution comparable to that achieved in cell cultures, providing new opportunities to study cell biology under physiological conditions. The overall aim of this review is to give the reader a general idea of the potential applications of intravital microscopy with a particular emphasis on subcellular imaging. An overview of some of the most exciting studies in this field will be presented using resolution as a main organizing criterion. Indeed, first we will focus on those studies in which organs were imaged at the tissue level, then on those focusing on single cells imaging, and finally on those imaging subcellular organelles and structures.


Asunto(s)
Estructuras Animales/citología , Células/citología , Técnicas Citológicas/métodos , Microscopía/métodos , Animales , Biología Celular , Microscopía/tendencias , Microscopía Fluorescente/métodos , Microscopía Fluorescente/tendencias
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