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1.
Adv Healthc Mater ; : e2401406, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007245

RESUMO

Tissue engineering for penile corpora cavernosa defects requires microvascular system reconstruction.GelMA hydrogels show promise for tissue regeneration. However, using stem cells faces challenges such as immune rejection, limited proliferation and differentiation, and biosafety concerns. Therefore, acellular tissue regeneration may avoid these issues. Exosomes are used from muscle-derived stem cells (MDSCs) to modify 3D-printed hydrogel scaffolds for acellular tissue regeneration. Hypoxia-preconditioned MDSC-derived exosomes are obtained to enhance the therapeutic effect. In contrast to normoxic exosomes (N-Exos), hypoxic exosomes (H-Exos) are found to markedly enhance the proliferation, migration, and capillary-like tube formation of human umbilical vein endothelial cells (HUVECs). High-throughput sequencing analysis of miRNAs isolated from both N-Exos and H-Exos revealed a significant upregulation of miR-21-5p in H-Exos following hypoxic preconditioning. Further validation demonstrated that the miR-21-5p/PDCD4 pathway promoted the proliferation of HUVECs. Epigallocatechin gallate (EGCG) is introduced to improve the mechanical properties and biocompatibility of GelMA hydrogels. EGCG-GelMA scaffolds loaded with different types of Exos are transplanted to repair rabbit penile corpora cavernosa defects, observed the blood flow and repair status of the defect site through color Doppler ultrasound and magnetic resonance imaging, and ultimately restored the rabbit penile erection function and successfully bred offspring. Thus, acellular hydrogel scaffolds offer an effective treatment for penile corpora cavernosa defects.

2.
Artigo em Inglês | MEDLINE | ID: mdl-23668408

RESUMO

Paroxetine hydrochloride (3S-trans)-3-[(1,3-benzodioxol-5-yloxy)methyl]-4-(4-fluorophenyl)-piperidine hydrochloride (or (-)-(3S,4R)-(4-(p-fluorophenyl)-3-[[3,4-(methylenedioxy)-phenoxy]methyl]piperidine hydrochloride), a phenylpiperidine derivative, is a selective serotonin reuptake inhibitor. Paroxetine is indicated for the treatment of depression, generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, posttraumatic stress disorder, and social anxiety disorder. The physicochemical properties, spectroscopic data (1D and 2D NMR, UV, FT-IR, MS, PXRD), stability, methods of preparation and chromatographic methods of analysis of pharmaceutical, and biological samples of paroxetine are documented in this review. Pharmacokinetics, metabolism, and pharmacological effects are also discussed.


Assuntos
Paroxetina/análise , Inibidores Seletivos de Recaptação de Serotonina/análise , Animais , Cromatografia , Estabilidade de Medicamentos , Humanos , Paroxetina/química , Paroxetina/farmacocinética , Análise Espectral
3.
Artigo em Inglês | MEDLINE | ID: mdl-23668411

RESUMO

A profile of the analgesic tramadol hydrochloride ((1RS,2RS)-2-[(dimethylamino)methyl]-1-(3-methoxyphenyl)cyclohexanol hydrochloride) is provided in this chapter and includes a summary of the physical characteristics known for this drug substance (e.g., UV/vis, IR, NMR, and mass spectra). Details regarding the stability of tramadol hydrochloride in the solid state and solution-phase are presented and methods of analysis (compendial and literature) are summarized. Furthermore, an account of biological properties and a description of the chemical synthesis of tramadol hydrochloride are given.


Assuntos
Analgésicos Opioides/análise , Tramadol/análise , Animais , Estabilidade de Medicamentos , Humanos , Solubilidade , Tramadol/química , Tramadol/farmacocinética
6.
Biochemistry ; 44(28): 9785-94, 2005 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-16008363

RESUMO

We employed ultrasonic velocimetry, high-precision densimetry, circular dichroism and fluorescence spectroscopy, and isothermal titration calorimetry to characterize the binding of Hoechst 33258 to the d(CGCGAATTCGCG)(2) oligomeric duplex at 25 degrees C. We used this experimental combination to determine the full thermodynamic profile for the binding of Hoechst 33258 to the DNA. Specifically, we report changes in binding free energy, enthalpy, entropy, volume, and adiabatic compressibility accompanying the binding. We interpret our volumetric data in terms of hydration and evaluate the number of waters of hydration that become released to or taken up from the bulk. Our calorimetric data reveal that the drug-DNA binding event studied in this work is entropy-driven and proceeds with an unfavorable change in enthalpy. The favorable binding entropy predominantly results from hydration changes. In contrast to a large and positive change in hydrational entropy, the binding-induced change in configurational entropy is insignificant. The latter observation is consistent with the "lock-and-key" mode of minor groove binding.


Assuntos
Bisbenzimidazol/química , DNA/química , Ácidos Nucleicos Heteroduplexes/química , Oligonucleotídeos/química , Termodinâmica , Sítios de Ligação , Calorimetria , Dicroísmo Circular , Densitometria , Entropia , Modelos Químicos , Conformação de Ácido Nucleico , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Ultrassom
7.
J Am Chem Soc ; 125(24): 7219-29, 2003 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-12797795

RESUMO

We use high precision ultrasonic velocimetric and densimetric techniques to determine at 25 degrees C the changes in volume, deltaV, and adiabatic compressibility, deltaK(S), that accompany the binding of ethidium to the poly(rA)poly(rU), poly(dAdT)poly(dAdT), poly(dGdC)poly(dGdC), and poly(dIdC)poly(dIdC) duplexes, as well as to the poly(rU)poly(rA)poly(rU) triplex. The binding of ethidium to each of the duplexes and the triplex is accompanied by negative changes in volume, deltaV, and adiabatic compressibility, deltaK(S). We discuss the basis for relating macroscopic and microscopic properties, particularly, emphasizing how measured changes in volume and compressibility can be quantitatively interpreted in terms of the differential hydration properties of DNA and RNA structures in their ligand-free and ligand-bound states. We also estimate the entropic cost of intercalation-induced changes in hydration of each of the nucleic acid structures and the drug. In general, our results emphasize the vital role of hydration in modulating the energetics of drug-DNA binding, while also underscoring the fact that hydration must be carefully taken into account in analysis and prediction of the energetics of nucleic acid recognition.


Assuntos
DNA/química , Etídio/química , Substâncias Intercalantes/química , Polinucleotídeos/química , RNA/química , Dicroísmo Circular , DNA/metabolismo , Etídio/metabolismo , Etídio/farmacologia , Substâncias Intercalantes/metabolismo , Substâncias Intercalantes/farmacologia , Cinética , Concentração Osmolar , Polinucleotídeos/metabolismo , RNA/metabolismo , Termodinâmica , Água/química , Água/metabolismo
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