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1.
J Appl Toxicol ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044430

RESUMEN

The increasing use of industrial chemicals has raised concerns regarding exposure to endocrine-disrupting chemicals (EDCs), which interfere with developmental, reproductive and metabolic processes. Of particular concern is their interaction with adipose tissue, a vital component of the endocrine system regulating metabolic and hormonal functions. The SGBS (Simpson Golabi Behmel Syndrome) cell line, a well-established human-relevant model for adipocyte research, closely mimics native adipocytes' properties. It responds to hormonal stimuli, undergoes adipogenesis and has been successfully used to study the impact of EDCs on adipose biology. In this study, we screened human exposure-relevant doses of various EDCs on the SGBS cell line to investigate their effects on viability, lipid accumulation and adipogenesis-related protein expression. Submicromolar doses were generally well tolerated; however, at higher doses, EDCs compromised cell viability, with cadmium chloride (CdCl2) showing the most pronounced effects. Intracellular lipid levels remained unaffected by EDCs, except for tributyltin (TBT), used as a positive control, which induced a significant increase. Analysis of adipogenesis-related protein expression revealed several effects, including downregulation of fatty acid-binding protein 4 (FABP4) by dibutyl phthalate, upregulation by CdCl2 and downregulation of perilipin 1 and FABP4 by perfluorooctanoic acid. Additionally, TBT induced dose-dependent upregulation of C/EBPα, perilipin 1 and FABP4 protein expression. These findings underscore the importance of employing appropriate models to study EDC-adipocyte interactions. Conclusions from this research could guide strategies to reduce the negative impacts of EDC exposure on adipose tissue.

2.
Leukemia ; 37(11): 2209-2220, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37709843

RESUMEN

Hematopoietic stem cells (HSCs) ensure blood cell production during the life-time of an organism, and to do so they need to balance self-renewal, proliferation, differentiation, and migration in a steady state as well as in response to stress or injury. Importantly, aberrant proliferation of HSCs leads to hematological malignancies, and thus, tight regulation by various tumor suppressor pathways, including p53, is essential. Protein phosphatase magnesium-dependent 1 delta (PPM1D) is a negative regulator of p53 and promotes cell survival upon induction of genotoxic stress. Truncating mutations in the last exon of PPM1D lead to the production of a stable, enzymatically active protein and are commonly associated with clonal hematopoiesis. Using a transgenic mouse model, we demonstrate that truncated PPM1D reduces self-renewal of HSCs in basal conditions but promotes the development of aggressive AML after exposure to ionizing radiation. Inhibition of PPM1D suppressed the colony growth of leukemic stem and progenitor cells carrying the truncated PPM1D, and remarkably, it provided protection against irradiation-induced cell growth. Altogether, we demonstrate that truncated PPM1D affects HSC maintenance, disrupts normal hematopoiesis, and that its inhibition could be beneficial in the context of therapy-induced AML.


Asunto(s)
Leucemia Mieloide Aguda , Proteína p53 Supresora de Tumor , Animales , Ratones , Proliferación Celular , Daño del ADN , Leucemia Mieloide Aguda/genética , Mutación , Proteína p53 Supresora de Tumor/genética
3.
Drug Dev Ind Pharm ; 36(9): 1115-30, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20545516

RESUMEN

BACKGROUND: Oxycellulose (OC) is biodegradable and bioabsorbable cellulose derivative used in medicine to support hemostasis and tissue healing. Recently, its antimicrobial and immunomodulating properties, as well as its potential in modern therapeutic systems as release modifying excipient, drug carrier, and/or mucoadhesive polymer, are widely discussed. METHOD: To study its last-mentioned characteristics, directly compressed tablets containing 5 mg of cetylpyridinium chloride (CPC) as a model drug and 90 mg of mucoadhesive polymer [oxycellulose sodium (NaOC) alone or in a combination with one of five widely used mucoadhesive polymers] were prepared to ensure 8 hours prolonged release of CPC. Physicochemical and mucoadhesive properties of prepared tablets were evaluated. RESULTS: Based on obtained results, tablets containing OC in combination with hydroxypropylmethylcellulose (Methocel K100LV) or carboxymethylcellulose sodium showed the best quality parameters (friability < 0.04%, tablet thickness < 2.17 mm, tablet hardness > 85 N, residence time > 256 minutes, mucoadhesive strength > 3.45 mN/mm(2) ) and dissolution profiles (more than 81% of CPC released within 8 hours). CONCLUSION: NaOC embodies excellent compressing, mechanical, and mucoadhesive properties; however, formulation with higher content of NaOC only showed shorter adhesion time (107 +/- 7 minutes) and faster drug release (93.66% of CPC released within 2 hours), because of its good solubility in aqueous media.


Asunto(s)
Antiinfecciosos Locales/química , Cetilpiridinio/química , Excipientes/química , Metilcelulosa/análogos & derivados , Adhesividad , Administración Bucal , Antiinfecciosos Locales/administración & dosificación , Mejilla , Portadores de Fármacos , Derivados de la Hipromelosa , Metilcelulosa/química , Mucosa Bucal , Tamaño de la Partícula , Polímeros/química , Solubilidad , Comprimidos , Viscosidad
4.
Medicina (Kaunas) ; 39 Suppl 2: 19-24, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14617853

RESUMEN

Recently, controlled and sustained drug delivery has become the standard in modern pharmaceutical design and an intensive research has been undertaken in achieving much better drug product effectiveness, reliability and safety. In this regard, many polymers are very useful with majority of hydrogels, which undergo reversible volume and/or sol-gel phase transitions in response to physiological (temperature, pH and present of ions in organism fluids, blood glucose level) or other external (electric current, light) stimuli. This article reviews the main stimuli-sensitive hydrogels and the use of these hydrogels in parenteral, ocular, peroral, rectal, vaginal, nasal, dermal and transdermal drug delivery.


Asunto(s)
Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Hidrogeles , Administración Oral , Administración Rectal , Vías de Administración de Medicamentos , Humanos , Concentración de Iones de Hidrógeno , Infusiones Parenterales , Polímeros
5.
Medicina (Kaunas) ; 39 Suppl 2: 117-21, 2003.
Artículo en Lituano | MEDLINE | ID: mdl-14617871

RESUMEN

UNLABELLED: Heavy metals (lead, cadmium) are possible dashes which quantity is defined by the limiting acceptable contents. Different drugs preparations: infusions, decoctions, tinctures, extracts, etc. are produced using medicinal plants. The objective of this research was to study the impurities of heavy metals (lead, cadmium) in medicinal plants and some drug preparations. MATERIALS AND METHODS: We investigated liquid extracts of fruits Crataegus monogyna Jacq. and herbs of Echinacea purpurea Moench., tinctures--of herbs Leonurus cardiaca L. The raw materials were imported from Poland. Investigations were carried out in cooperation with the Laboratory of Antropogenic Factors of the Institute for Biomedical Research. Amounts of lead and cadmium were established after "dry" mineralisation using "Perkin-Elmer Zeeman/3030" model electrothermic atomic absorption spectrophotometer (ETG AAS/Zeeman). It was established that lead is absorbed most efficiently after estimation of absorption capacity of cellular fibers. About 10.73% of lead crosses tinctures and extracts, better cadmium--49.63%. Herbs of Leonurus cardiaca L. are the best in holding back lead and cadmium. About 14.5% of lead and cadmium crosses the tincture of herbs Leonurus cardiaca L. We estimated the factors of heavy metals (lead, cadmium) in the liquid extracts of Crataegus monogyna Jacq. and Echinacea purpurea Moench., tincture of Leonurus cardiaca L. after investigations of heavy metals (lead, cadmium) in drugs and preparations of it. The amounts of heavy metals (lead, cadmium) don't exceed the allowable norms in fruits of Crataegus monogyna Jacq., herbs of Leonurus cardiaca L. and Echinacea purpurea Moench. after estimation of lead and cadmium extraction factors, the maximum of acceptable daily intake and the quantity of drugs consumption in day.


Asunto(s)
Cadmio/análisis , Crataegus/química , Echinacea/química , Plomo/análisis , Leonurus/química , Extractos Vegetales/química , Humanos , Concentración Máxima Admisible , Modelos Químicos , Espectrofotometría Atómica
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