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1.
J Pediatr Endocrinol Metab ; 30(4): 475-478, 2017 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-28328532

RÉSUMÉ

BACKGROUND: Adenocorticotropic hormone (ACTH)-dependent Cushing's syndrome in infancy is extremely rare. We describe the case of a sacro-coccygeal ectopic ACTH-secreting immature teratoma in an infant who also presented the triad of defects characteristic of Currarino syndrome. CASE PRESENTATION: A girl was born with a large immature teratoma in the sacro-coccygeal region associated with anal atresia. At the age of 7 days, the concentration of α-fetoprotein (AFP) was above the age-specific normal range. Two non-radical surgical excisions of the tumour were performed. At the age of 7 months, she developed polyphagia, acne, hirsutism, hypertension and hypokalemia with elevated ACTH and absence of serum cortisol circadian rhythm. Immunostaining of tumour tissue showed ACTH-immunoreactive cells. Due to unsuccessful therapy with ketoconazole and resistance to antihypertensive medications [blood pressure (BP) 210/160 mmHg], metyrapone was administered, which controlled her ACTH and cortisol levels in the normal range. Following further removal of tumour bulk after three operations during the first year of life, there was a decrease of BP to normal values. CONCLUSIONS: A rare case of ectopic ACTH syndrome causing Cushing's syndrome in infancy in the context of Currarino syndrome is reported. Radical surgery has resulted in excision of the tumour and current control of Cushing's syndrome.


Sujet(s)
Syndrome de sécrétion ectopique d'ACTH/complications , Hormone corticotrope/métabolisme , Coccyx/anatomopathologie , Syndrome de Cushing/étiologie , Sacrum/anatomopathologie , Tératome/anatomopathologie , Syndrome de sécrétion ectopique d'ACTH/sang , Syndrome de sécrétion ectopique d'ACTH/thérapie , Adulte , Enfant d'âge préscolaire , Coccyx/métabolisme , Syndrome de Cushing/sang , Syndrome de Cushing/thérapie , Femelle , Humains , Pronostic , Sacrum/métabolisme , Tératome/métabolisme
2.
Stem Cell Res Ther ; 7(1): 75, 2016 May 23.
Article de Anglais | MEDLINE | ID: mdl-27216150

RÉSUMÉ

BACKGROUND: The intervertebral disc (IVD) has limited self-healing potential and disc repair strategies require an appropriate cell source such as progenitor cells that could regenerate the damaged cells and tissues. The objective of this study was to identify nucleus pulposus-derived progenitor cells (NPPC) and examine their potential in regenerative medicine in vitro. METHODS: Nucleus pulposus cells (NPC) were obtained from 1-year-old bovine coccygeal discs by enzymatic digestion and were sorted for the angiopoietin-1 receptor Tie2. The obtained Tie2- and Tie2+ fractions of cells were differentiated into osteogenic, adipogenic, and chondrogenic lineages in vitro. Colony-forming units were prepared from both cell populations and the colonies formed were analyzed and quantified after 8 days of culture. In order to improve the preservation of the Tie2+ phenotype of NPPC in monolayer cultures, we tested a selection of growth factors known to have stimulating effects, cocultured NPPC with IVD tissue, and exposed them to hypoxic conditions (2 % O2). RESULTS: After 3 weeks of differentiation culture, only the NPC that were positive for Tie2 were able to differentiate into osteocytes, adipocytes, and chondrocytes as characterized by calcium deposition (p < 0.0001), fat droplet formation (p < 0.0001), and glycosaminoglycan content (p = 0.0095 vs. Tie2- NPC), respectively. Sorted Tie2- and Tie2+ subpopulations of cells both formed colonies; however, the colonies formed from Tie2+ cells were spheroid in shape, whereas those from Tie2- cells were spread and fibroblastic. In addition, Tie2+ cells formed more colonies in 3D culture (p = 0.011) than Tie2- cells. During expansion, a fast decline in the fraction of Tie2+ cells was observed (p < 0.0001), which was partially reversed by low oxygen concentration (p = 0.0068) and supplementation of the culture with fibroblast growth factor 2 (FGF2) (p < 0.0001). CONCLUSIONS: Our results showed that the bovine nucleus pulposus contains NPPC that are Tie2+. These cells fulfilled formally progenitor criteria that were maintained in subsequent monolayer culture for up to 7 days by addition of FGF2 or hypoxic conditions. We propose that the nucleus pulposus represents a niche of precursor cells for regeneration of the IVD.


Sujet(s)
Angiopoïétine-1/génétique , Chondrocytes/métabolisme , Nucleus pulposus/métabolisme , Récepteur TIE-2/génétique , Cellules souches/métabolisme , Adipocytes/cytologie , Adipocytes/effets des médicaments et des substances chimiques , Adipocytes/métabolisme , Angiopoïétine-1/métabolisme , Animaux , Bovins , Différenciation cellulaire , Hypoxie cellulaire , Chondrocytes/cytologie , Chondrocytes/effets des médicaments et des substances chimiques , Coccyx/cytologie , Coccyx/effets des médicaments et des substances chimiques , Coccyx/métabolisme , Techniques de coculture , Expression des gènes , Protéines et peptides de signalisation intercellulaire/pharmacologie , Nucleus pulposus/cytologie , Nucleus pulposus/effets des médicaments et des substances chimiques , Ostéoblastes/cytologie , Ostéoblastes/effets des médicaments et des substances chimiques , Ostéoblastes/métabolisme , Récepteur TIE-2/métabolisme , Médecine régénérative , Transduction du signal , Cellules souches/cytologie , Cellules souches/effets des médicaments et des substances chimiques
3.
Anat Rec (Hoboken) ; 299(7): 819-27, 2016 07.
Article de Anglais | MEDLINE | ID: mdl-27149546

RÉSUMÉ

To examine how the median sacral artery (MSA) is involved with the coccygeal body or glomus coccygeum, we studied serial frontal or sagittal sections of 14 embryos (approximately 5-6 weeks of gestation) and 12 fetuses (10-18 weeks). At five weeks, the caudal end of the dorsal aorta (i.e., MSA) accompanied putative sympathetic ganglion cells in front of the upper coccygeal and lower sacral vertebrae. At six weeks, a candidate for the initial coccygeal body was identified as a longitudinal arterial plexus involving nerve fibers and sympathetic ganglion cells between arteries. At 10-18 weeks, the MSA exhibited a highly tortuous course at the lower sacral and coccygeal levels, and was attached to and surrounded by veins, nerve fibers, and sympathetic ganglion cells near and between the bilateral origins of the levator ani muscle. Immunohistochemistry demonstrated expression of tyrosine hydroxylase and chromogranin A in the nerves. However, throughout the stages examined, we found no evidence suggestive of an arteriovenous anastomosis, such as well-developed smooth muscle. An acute anterior flexure of the vertebrae at the lower sacrum, as well as regression of the secondary neural tube, seemed to induce arterial plexus formation from an initial straight MSA. Nerves and ganglion cells were likely to be secondarily involved with the plexus because of the close topographical relationship. However, these nerves might play a major role in the extreme change into adult morphology. An arteriovenous anastomosis along the MSA might be an overinterpretation, at least in the prenatal human. Anat Rec, 299:819-827, 2016. © 2016 Wiley Periodicals, Inc.


Sujet(s)
Artères/anatomie et histologie , Coccyx/anatomie et histologie , Embryon de mammifère/anatomie et histologie , Foetus/anatomie et histologie , Sacrum/anatomie et histologie , Système nerveux sympathique/anatomie et histologie , Artères/métabolisme , Marqueurs biologiques/métabolisme , Coccyx/métabolisme , Embryon de mammifère/métabolisme , Foetus/métabolisme , Humains , Sacrum/vascularisation , Sacrum/métabolisme , Système nerveux sympathique/métabolisme
4.
Spine (Phila Pa 1976) ; 31(5): 515-22, 2006 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-16508544

RÉSUMÉ

STUDY DESIGN: Whole bovine coccygeal discs were cultured under static load, with or without vertebral endplates (VEPs), and assessed for cell viability, biochemical stability, biosynthetic activity, and biosynthetic responsiveness to changes in mechanical load. OBJECTIVES: To assess the effects of VEPs on biochemical and cellular stability of disc cells during in vitro culture of large disc explants. To determine whether cultured discs could respond to mechanical perturbation. SUMMARY OF BACKGROUND DATA: Previous methods for culturing the intervertebral disc have focused on rabbit and rat discs, but the small size of these discs limits the relevance of these culture systems to the human condition. Bovine coccygeal discs have similar dimensions to the human lumbar disc (i.e., similar size and nominal stresses), but long-term culture of these discs has not been reported. METHODS: Bovine coccygeal discs were harvested with or without VEPs, cultured under static load (5 kg, approximately 0.25 MPa, in situ swelling pressure) for up to 1 week, and evaluated for changes in hydration, glycosaminoglycan content, cell viability, and biosynthetic activity. Additionally, the biochemical and biosynthetic response of discs cultured without VEP to increasing the load to a 20-kg (approximately 1 MPa, the estimated stress in human lumbar disc during heavy lifting) static load for 6 hours was assessed. RESULTS: During the first 24 hours, culturing discs with endplates was moderately better with regards to maintaining in situ anulus hydration and nucleus glycosaminoglycan levels. The endplates, however, obstructed media flow to the disc, resulting in a marked decrease in cell viability after 1 week of culture. Nucleus pulposus cell viability was maintained in discs cultured without endplates, but there was a significant drop in biosynthetic activity within 2 days of culture. Despite this drop, the disc cells in the discs without VEP remained biosynthetically responsive to changes in mechanical loading. CONCLUSIONS: It is possible to maintain cell viability and the biosynthetic responsiveness of large discs for up to 1 week in vitro when the discs are cultured under static load and without VEP.


Sujet(s)
Lame épiphysaire/cytologie , Lame épiphysaire/métabolisme , Disque intervertébral/cytologie , Disque intervertébral/métabolisme , Techniques de culture d'organes/méthodes , Animaux , Eau corporelle/composition chimique , Eau corporelle/métabolisme , Bovins , Survie cellulaire/physiologie , Coccyx/cytologie , Coccyx/métabolisme , Coccyx/physiologie , Résistance à la compression , Dessiccation , Glycosaminoglycanes/métabolisme , Lame épiphysaire/physiologie , Disque intervertébral/physiologie , Protéoglycanes/biosynthèse , Contrainte mécanique
5.
Spine (Phila Pa 1976) ; 29(24): 2793-9, 2004 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-15599281

RÉSUMÉ

STUDY DESIGN: The contents of DNA, proteoglycan, type II collagen, and denatured type II collagen in the bovine coccygeal intervertebral discs were examined in situ in relation to disc level, age, and tissue region. OBJECTIVE: To determine whether bovine coccygeal discs are a suitable model to study human lumbar discs. SUMMARY OF BACKGROUND DATA: Bovine coccygeal discs have been suggested as a suitable alternative model because they are readily available, in contrast to human discs, and represent a common source of tissue in the disc field. However, it is not known whether the changes in matrix contents in bovine coccygeal discs are similar to those found in the human lumbar spine. METHODS: Intervertebral discs from bovine tails were dissected into the nucleus pulposus (NP) and anulus fibrosus (AF). Tissues were weighed and analyzed for matrix contents using specific assays. RESULTS: Similar to water content, the proteoglycan content was higher in the NP than in the AF. Water content of the bovine NP did not change with age, unlike the proteoglycan content, which decreased. type II collagen content was higher in the NP than in the AF, and both did not change overall significantly with age. The percent of denatured type II collagen decreased with age only in the NP. The DNA content did not vary with age in the AF and in the NP. CONCLUSION: Differences in matrix contents exist between the bovine coccygeal discs and the human lumbar spine. Thus, caution must be exercised when using the bovine tail as a model for the human lumbar spine in biochemical studies.


Sujet(s)
Coccyx/métabolisme , Disque intervertébral/métabolisme , Modèles animaux , Vieillissement/physiologie , Animaux , Bovins , Coccyx/composition chimique , Collagène de type II/analyse , Collagène de type II/métabolisme , ADN/analyse , ADN/métabolisme , Matrice extracellulaire/composition chimique , Matrice extracellulaire/métabolisme , Humains , Disque intervertébral/composition chimique , Mâle , Dénaturation des protéines , Protéoglycanes/analyse , Protéoglycanes/métabolisme , Spécificité d'espèce , Queue , Eau/analyse , Eau/métabolisme
6.
J Anim Sci ; 72(10): 2681-9, 1994 Oct.
Article de Anglais | MEDLINE | ID: mdl-7883627

RÉSUMÉ

Two experiments were conducted with pigs 1) to determine the effect of supplemental Zn on growth performance, bone Zn, and plasma Zn in pigs fed Zn-unsupplemented, corn-soybean meal diets and 2) to assess bioavailability of Zn from inorganic and organic Zn sources. In both experiments, weanling pigs were fed a diet with no supplemental Zn for 5 wk to deplete their Zn stores. In Exp. 1, 192 pigs were fed a corn-soybean meal diet (growing diet, 32 mg/kg of Zn; finishing diet, 27 mg/kg of Zn) supplemented with feed-grade ZnSO4.H2O to provide 0, 5, 10, 20, 40, and 80 mg/kg of supplemental Zn. Supplemental Zn did not affect weight gain, feed intake, or gain/feed during either the growing or the finishing period (P > .05). However, bone and plasma Zn concentrations increased linearly (P < .01) in response to supplemental Zn at dietary Zn levels between 27 mg/kg (basal) and 47 mg/kg (breakpoint). In Exp. 2, three levels of supplemental Zn from ZnSO4.H2O (0, 7.5, and 15 mg/kg of supplemental Zn) were used to construct a standard curve (metacarpal, coccygeal vertebrae, and plasma Zn concentrations regressed on supplemental Zn intake; R2 = .93, .89, and .82, respectively). From the standard curve, the bone and plasma Zn concentrations obtained from pigs fed 15 mg/kg of supplemental Zn from ZnO and 7.5 mg/kg of supplemental Zn from Zn-methionine (ZnMET) and Zn-lysine (ZnLYS) were used to calculate bioavailable Zn via multiple linear regression, slope-ratio analysis. The estimates of Zn bioavailability differed depending on which variable was used. Overall trends indicated the following rankings: ZnSO4.H2O > ZnMet > ZnO > ZnLys.


Sujet(s)
Suidae/métabolisme , Zinc/pharmacocinétique , Aliment pour animaux , Animaux , Biodisponibilité , Coccyx/métabolisme , Femelle , Aliment enrichi , Lysine/pharmacocinétique , Mâle , Métacarpe/métabolisme , Méthionine/analogues et dérivés , Méthionine/pharmacocinétique , Composés organométalliques/pharmacocinétique , Répartition aléatoire , Analyse de régression , Glycine max , Sulfates/pharmacocinétique , Suidae/croissance et développement , Zea mays , Zinc/administration et posologie , Zinc/sang , Composés du zinc/pharmacocinétique , Oxyde de zinc/pharmacocinétique , Sulfate de zinc
7.
Eur Spine J ; 3(6): 325-30, 1994.
Article de Anglais | MEDLINE | ID: mdl-7866861

RÉSUMÉ

The effects of axial traction stress on intradiscal hydration, solute transport and proteoglycan synthesis were examined in 658 porcine coccygeal intervertebral discs in vitro. Measurements were performed in three tissue fractions: nucleus pulposus, inner and outer annulus fibrosus. At 0.80 MPa traction stress, the equilibrium hydration did not change in the nucleus pulposus. However, in the inner and outer annulus, the equilibrium hydration was reduced, and the change led to an increase of the effective fixed charge density. Diffusion of solute to the nucleus pulposus was significantly suppressed at 0.80 MPa traction stress. The fluid flow of the intervertebral disc tended to be suppressed during the creep recovery process after compression. The proteoglycan synthesis rate in the outer annulus was markedly suppressed by traction stress of 0.80 MPa for 4 h, but not that in the nucleus pulposus. These results suggest that a prolonged excessive axial traction stress induces a decrease in tissue hydration in the annulus fibrosus, and this may lead to an increase in the fractional volume of solid in the matrix and tissue osmotic pressure, resulting in diffusion inhibition of solute and suppression of proteoglycan synthesis. Thus, prolonged and excessive spinal traction may accelerate disc degeneration.


Sujet(s)
Coccyx/métabolisme , Disque intervertébral/physiologie , Protéoglycanes/biosynthèse , Traction , Animaux , Transport biologique/physiologie , Eau corporelle/métabolisme , Femelle , Techniques in vitro , Disque intervertébral/métabolisme , Mâle , Contrainte mécanique , Suidae , Traction/effets indésirables , Tritium
8.
Article de Anglais | MEDLINE | ID: mdl-2503930

RÉSUMÉ

We describe on a primary, subcutaneous sacrococcygeal ependymoma presenting in a young female patient. Detailed immunohistochemical and electron microscopic examinations were performed. Out of the 40 similar cases reported in literature this is the first in which the determination of DNA content was also used to predict biological behaviour. The tumour proved to be aneuploid with low proliferative capacity in spite of absent histological signs of malignancy. It is suggested that DNA determination may be helpful in establishing prognosis and that it may contribute to a better understanding of the biological behaviour of this tumour.


Sujet(s)
Coccyx/anatomopathologie , Épendymome/anatomopathologie , Sacrum/anatomopathologie , Tumeurs du rachis/anatomopathologie , Adulte , Transformation cellulaire néoplasique/métabolisme , Transformation cellulaire néoplasique/anatomopathologie , Coccyx/métabolisme , Coccyx/ultrastructure , Cytophotométrie , ADN tumoral/métabolisme , Épendymome/métabolisme , Épendymome/ultrastructure , Femelle , Humains , Immunohistochimie , Microscopie électronique , Organites/ultrastructure , Sacrum/métabolisme , Sacrum/ultrastructure , Tumeurs du rachis/métabolisme , Tumeurs du rachis/ultrastructure
9.
J Anim Sci ; 55(2): 350-6, 1982 Aug.
Article de Anglais | MEDLINE | ID: mdl-6982891

RÉSUMÉ

Sixteen ram lambs were fed 0, 50 or 200 ppm supplemental vanadium daily as NH4VO3 for 90 d and coccygeal vertebrae were sampled at 0, 15, 30, 60 and 90 d after the imposition of dietary treatments. Vertebral vanadium content was elevated (P less than .05) after exposure to 200 ppm added vanadium in the diet of 15 d, but nonsignificant increases occurred thereafter. Increasing dietary vanadium increased bone ash vanadium concentration from .4 to 1.7 and 3.8 ppm in sheep fed 0, 50 and 200 ppm supplemental vanadium, respectively. In a balance study, urinary concentrations of the element also were related directly to dietary intake. A trend toward elevated urine volume with increased intake of vanadium was also observed.


Sujet(s)
Os et tissu osseux/métabolisme , Ovis/métabolisme , Vanadium/métabolisme , Absorption , Animaux , Poids/effets des médicaments et des substances chimiques , Coccyx/métabolisme , Consommation alimentaire/effets des médicaments et des substances chimiques , Fèces/analyse , Mâle , Vanadium/pharmacologie , Vanadium/urine
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