Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros

Banco de datos
Tipo de estudio
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Hum Reprod ; 36(2): 367-380, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33355349

RESUMEN

STUDY QUESTION: Are there phase-specific changes in the early secretory (ES) phase human tubal lavage proteome that can inform and potentially optimize IVF culture media? SUMMARY ANSWER: The human tubal lavage proteome during the ES phase relative to the menstrual phase reveals substantial differential protein abundance in pathways such as glycolysis, redox homeostasis and activation of 14-3-3 zeta-mediated signaling. WHAT IS KNOWN ALREADY: The Fallopian tube is uniquely suited to the development of the preimplantation embryo as it transits the tube during the ES phase of the menstrual cycle. Euploid cleavage-stage embryo arrest may reflect incomplete recapitulation of in-vivo conditions by current media formulations. STUDY DESIGN, SIZE, DURATION: Proteome-wide analysis of distal tubal lavage specimens collected from 26 healthy women undergoing open microtubal anastomosis surgery from January 2013 to January 2018 was performed. Specimens were grouped by menstrual cycle phase in order to analyze phase-specific differences in protein abundance. For the murine embryo assay, single-cell embryos (N = 482) were collected from superovulated wild type C57BL/6 female mice and cultured in microdrops over 5 days for the assessment of blastocyst development. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human tubal lavage specimens were processed for label-free mass spectrometry. Reported menstrual cycle day was confirmed by measuring serum hormones. Key protein targets in the ES phase were validated via immunoblot. The ES phase-specific increase in 14-3-3 zeta protein was confirmed via ELISA of conditioned media obtained from primary human Fallopian tube epithelial cell culture. A murine embryo assay was performed to investigate the impact of graduated concentrations of 14-3-3 zeta on the blastocyst development rate. MAIN RESULTS AND THE ROLE OF CHANCE: Comparison of the ES and menstrual phase human tubal lavage proteomes revealed 74 differentially expressed proteins with enrichment of pathways and biological processes involved in the regulation of carbohydrate metabolism, oxidative stress and cell survival. The adapter-regulator protein 14-3-3 zeta was among the most significantly increased in the ES phase. Supplementation of embryo culture media with 14-3-3 zeta at concentrations tested did not significantly improve the murine blastocyst development. LIMITATIONS, REASONS FOR CAUTION: Although select associations were recapitulated in the conditioned media from sex steroid exposed primary human tubal epithelial cells, cell culture represents an in-vitro approximation. Changes to embryo culture media, such as protein supplementation, must undergo rigorous preclinical safety testing prior to adoption for human use. WIDER IMPLICATIONS OF THE FINDINGS: This study represents the first description of the human Fallopian tube lavage proteome across the menstrual cycle, revealing a unique proteomic signature during the ES phase. Although supplementation of culture media with 14-3-3 zeta at appropriate concentrations showed no significant impact on the murine blastocyst development rate, other biologically plausible candidate proteins for individual or high throughput testing strategies are identified. STUDY FUNDING/COMPETING INTEREST(S): This work was funded in part by an Army Medical Department Advanced Medical Technology Initiative grant from the United States Army Medical Research and Materiel Command's Telemedicine and Advanced Technology Research Center. There are no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Trompas Uterinas , Proteoma , Animales , Blastocisto , Técnicas de Cultivo de Embriones , Femenino , Fertilización In Vitro , Humanos , Ratones , Ratones Endogámicos C57BL , Proteómica , Irrigación Terapéutica
2.
Appl Opt ; 60(19): D52-D72, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34263828

RESUMEN

Over the last decade, the vector-apodizing phase plate (vAPP) coronagraph has been developed from concept to on-sky application in many high-contrast imaging systems on 8 m class telescopes. The vAPP is a geometric-phase patterned coronagraph that is inherently broadband, and its manufacturing is enabled only by direct-write technology for liquid-crystal patterns. The vAPP generates two coronagraphic point spread functions (PSFs) that cancel starlight on opposite sides of the PSF and have opposite circular polarization states. The efficiency, that is, the amount of light in these PSFs, depends on the retardance offset from a half-wave of the liquid-crystal retarder. Using different liquid-crystal recipes to tune the retardance, different vAPPs operate with high efficiencies (${\gt}96\%$) in the visible and thermal infrared (0.55 µm to 5 µm). Since 2015, seven vAPPs have been installed in a total of six different instruments, including Magellan/MagAO, Magellan/MagAO-X, Subaru/SCExAO, and LBT/LMIRcam. Using two integral field spectrographs installed on the latter two instruments, these vAPPs can provide low-resolution spectra (${\rm{R}} \sim 30$) between 1 µm and 5 µm. We review the design process, development, commissioning, on-sky performance, and first scientific results of all commissioned vAPPs. We report on the lessons learned and conclude with perspectives for future developments and applications.

3.
Opt Express ; 27(23): 33925-33941, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31878452

RESUMEN

Detecting and monitoring gas species is an important part of remote sensing because the state of the environment can be retrieved from the state of the gas species. This can be used to track temperature and pressure structures in the atmosphere for weather predictions, or monitor the air quality. Discriminating different species is easier at higher spectral resolution when the spectral lines are clearly resolved. The need to do this at high spatial resolution and over large fields of view leads to a trade-off between spectral and spatial resolution and spectral bandwidth. We propose to use a highly multiplexed Bragg grating that can optically combine the relevant information from the spectrum without the need to disperse the whole spectrum. This allows us to circumvent the spatial and spectral trade-off and therefore substantially increase the field of view compared to conventional hyperspectral imagers. A dynamic implementation based on acousto-optical filters that can be adapted on the fly is discussed as an easy and flexible way to create the multiplexed gratings. We describe the details of multiplexed Bragg gratings and show that we can retrieve the spatial distribution of individual species abundances in gas mixtures, and we show that we can even do this for the atmospheres of exoplanets orbiting far-away stars.

4.
Cell Death Differ ; 13(3): 512-23, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16167066

RESUMEN

Dexamethasone (DEX) pretreatment protected hepatocytes from TNF-alpha plus actinomycin D (ActD)-induced apoptosis by suppressing caspase-8 activation and the mitochondria-dependent apoptosis pathway. DEX treatment upregulated cellular FLICE inhibitory protein (cFLIP) expression, but did not alter the protein levels of Bcl-2, Bcl-xL, Mcl-1, and cIAP as well as Akt activation. The increased cFLIP mRNA level by DEX was inhibited by ActD, indicating that DEX upregulates cFLIP expression at the transcriptional step. DEX also inhibited Jo2-mediated hepatocyte apoptosis by blocking the formation of the death-inducing signaling complex and caspase-8 activation. Specific downregulation of cFLIP expression using siRNA reversed the antiapoptotic effect of DEX by increasing caspase-8 activation. Moreover, DEX administration into mice increased cFLIP expression in the liver and prevented Jo2-induced hepatic injury by inhibiting caspase-8 and -3 activities. Our results indicate that DEX exerts a protective role in death receptor-induced in vitro and in vivo hepatocyte apoptosis by upregulating cFLIP expression.


Asunto(s)
Apoptosis/efectos de los fármacos , Dexametasona/farmacología , Hepatocitos/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Receptores del Factor de Necrosis Tumoral/antagonistas & inhibidores , Animales , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD , Caspasa 3 , Caspasa 8 , Caspasa 9 , Inhibidores de Caspasas , Caspasas/metabolismo , Células Cultivadas , Citocromos c/metabolismo , Dactinomicina/antagonistas & inhibidores , Proteínas Adaptadoras de Señalización del Receptor del Dominio de Muerte , Galactosamina/antagonistas & inhibidores , Hepatocitos/citología , Hepatocitos/metabolismo , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Interferencia de ARN , Ratas , Ratas Sprague-Dawley , Activación Transcripcional , Péptidos y Proteínas Asociados a Receptores de Factores de Necrosis Tumoral/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Regulación hacia Arriba , Receptor fas/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA