RESUMO
Histiotrophic nutrition is a process whereby the rodent visceral yolk sac (VYS) internalizes exogenous macromolecules, degrades them, and sends the degradation products to the embryo. Quantification and visualization of histiotrophic nutrition can be accomplished using fluorescent tracer molecules such as fluorescein isothiocyanate-conjugated albumin (FITC-albumin). The methods are simple and can provide complimentary functional and structural information in studies of the effects of embryotoxicants on visceral yolk sac function.
Assuntos
Embrião de Mamíferos/citologia , Fluoresceína-5-Isotiocianato/análogos & derivados , Corantes Fluorescentes/metabolismo , Albumina Sérica/metabolismo , Saco Vitelino/metabolismo , Animais , Técnicas de Cultura Embrionária , Embrião de Mamíferos/metabolismo , Endocitose , Fluoresceína-5-Isotiocianato/metabolismo , Microscopia de Fluorescência , Proteólise , RatosRESUMO
Histiotrophic nutrition is a process whereby the rodent visceral yolk sac (VYS) internalizes exogenous macromolecules, degrades them, and sends the degradation products to the embryo for use in de novo macromolecular biosynthesis. This process is important for embryonic development during early gestation prior to the formation of the functional placenta. Quantification and visualization of histiotrophic nutrition can be accomplished using fluorescent tracer molecules such as fluorescein isothiocyanate-conjugated albumin (FITC-albumin) that can be visualized using fluorescent microscopy and quantified using fluorescent spectroscopy. The methods are simple and can provide complementary functional and structural information in studies of the effects of embryotoxicants on yolk sac function.
Assuntos
Saco Vitelino/fisiologia , Absorção , Animais , Técnicas de Cultura Embrionária , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/fisiologia , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Corantes Fluorescentes/metabolismo , Microscopia de Fluorescência , Fenômenos Fisiológicos da Nutrição , Ratos , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , Saco Vitelino/metabolismoRESUMO
OBJECTIVE: To determine the interobserver and intraobserver reliability of the interpretation of MRIs for supraspinatus tendinosis. METHODS: In the interobserver trial, the MRIs of 52 athletes' shoulders were observed by 3 observers on one occasion within a 2-month period. All 52 images were read by the most experienced musculoskeletal radiologist on 3 different occasions on separate days without access to the previous readings for the intraobserver trial. Supraspinatus tendinosis was graded using a modified 4-point scale from grades 0 to grade 3. RESULTS: The grading of MRI-determined supraspinatus tendinosis was reliable, having an intraclass correlation (ICC) of 0.85 when assessed by the single well-trained observer. Interobserver reliability was only fair to good (ICC = 0.55). CONCLUSIONS: Supraspinatus tendinosis can be accurately identified on MRI with little variation by a single well-trained observer. Interobserver reliability was only fair to good. Our data indicated that the reliability of the assessment was much greater in more experienced radiologists than in those with less experience.