RESUMO
The in vivo behavior of monomethoxypoly(ethylene oxide)-poly(lactic acid) (MPEO20-PLA45/PLA (75/25)) nanoparticles in comparison with PLA ones was studied in guinea pig. Indeed, the aim of this study was to bring to the fore the in vivo stealth character of these copolymer nanoparticles and to identify the phagocytic circulating cells involved in their uptake. After the intravascular administration of fluorescent nanoparticles (rubrene), their phagocytosis by granulocytes and monocytes was assayed by flow cytometry. At the same time, the evolution of the number of these phagocytic cells was realized in order to identify their function in the nanoparticle uptake. Finally, a histological study of the spleen (30 h after the nanoparticle administration) was investigated to highlight the splenic trapping of these stealth nanoparticles. This study has shown that the phagocytic circulating cells involved in the nanoparticle uptake were mainly neutrophilic granulocytes and some of them were found in the spleen.
Assuntos
Materiais Biocompatíveis/farmacocinética , Ácido Láctico/farmacocinética , Neutrófilos/fisiologia , Fagocitose , Polietilenoglicóis/farmacocinética , Polímeros/farmacocinética , Animais , Biodegradação Ambiental , Transporte Biológico , Citometria de Fluxo , Cobaias , Masculino , Naftacenos/farmacocinética , Poliésteres , Baço/citologiaRESUMO
We report 6 cases of corticotroph macroadenomas which show heterogeneity of clinical and biological features (from Cushing's syndrome to silent adenoma) and heterogeneity of immunocytochemical staining. One patient reported on had skin hyperpigmentation and ACTH hypersecretion without clear abnormal adrenocortical function; we believe that this patient's plasma contained ACTH with very low bioactivity.
Assuntos
Adenoma/diagnóstico , Hormônio Adrenocorticotrópico/metabolismo , Neoplasias Hipofisárias/diagnóstico , Adenoma/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/metabolismoRESUMO
The diagnostic designs for the Laser Megajoule (LMJ) will require components to operate in environments far more severe than those encountered in present facilities. This harsh environment will be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiations, and, in some cases, debris and shrapnel, at levels several orders of magnitude higher than those experienced today on existing facilities. The lessons learned about the vulnerabilities of present diagnostic parts fielded mainly on OMEGA for many years, have been very useful guide for the design of future LMJ diagnostics. The present and future LMJ diagnostic designs including this vulnerability approach and their main mitigation techniques will be presented together with the main characteristics of the LMJ facility that provide for diagnostic protection.
RESUMO
Human (H-) CCR5 is the primary coreceptor for ENV-mediated fusion by R5 strains of human immunodeficiency virus type 1, whereas mouse (M-) CCR5 lacks this function. An array of 23 H/M-CCR5 hybrids containing increasing amounts of H-CCR5 extending from the N terminus generated by random chimeragenesis had a biphasic pattern of coreceptor activity with JRFL and 89.6, revealing active regions in the N-terminal extracellular domain (N-ED) and at the junction of cytoplasmic loop 3. The M-CCR5 mutant in which divergent residues were replaced with the corresponding H-CCR5 N-ED sequence (NyYTsE) gained coreceptor function in fusion but not infection experiments. A M-CCR5 double mutant with substitution of human sequences for divergent residues from the N-ED and cytoplasmic loop 3 had augmented coreceptor activity in fusion assays and gain of function in infection experiments. The SIV-251 ENV utilized H- and M-CCR5 and variants. Flow cytometric analysis of M-CCR5 mutants and bifunctional receptors composed of CD4 domains fused to M-CCR5 mutants excluded the possibility that differences in coreceptor activity resulted from variations in cell surface expression. These results demonstrate that the coreceptor activity of the H-CCR5 N-ED is modulated by intracellular residues, illustrating the complexity of CCR5 requirements for interaction with ENV.