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1.
Animal ; 18(9): 101271, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39213911

RESUMO

Reduced piglet feed intake immediately postweaning (pw) leads to disruption of small intestine structure and function and reduced growth. Our objective was to evaluate the effect of providing supplemental milk or liquid starter diet for either 4 or 11 days pw, on intestinal parameters of newly weaned piglets and growth to slaughter. At weaning (28 ± 0.6 days old), five hundred and eighty-seven piglets ((Large White × Landrace) × Duroc) were divided into 59 pen groups, each containing 9-10 same sex (entire male or female) piglets. The pen groups were blocked by sex and weaning weight and provided with ad-libitum access to one of five dietary treatments: (1) Dry pelleted starter diet (control; CON); (2) CON+liquid milk replacer for 4 days pw (M4); (3) CON+liquid milk replacer for 11 days pw (M11); (4) CON+liquid starter diet for 4 days pw (S4) and (5) CON+liquid starter diet for 11 days pw (S11). Pen groups were weighed at weaning, days 11, 20, 28, and 47 pw and at target sale weight. Feed disappearance (on a DM basis) was recorded on each weighing day. On day 7 pw, 10 piglets per treatment were euthanised to collect small intestine tissue samples for determination of villus height (VH), crypt depth and brush-border membrane enzyme activity. Data were analysed using SAS-version 9.4. Between days 0 and 11 pw, M11 increased average daily feed intake by 48% and average daily gain (ADG) by 57% compared to CON (P < 0.05), and increased ADG by 54% (P < 0.05) compared to S4. Piglets on M11 also had improved feed conversion efficiency compared with CON piglets between days 0 and 11 pw. Treatment did not affect growth performance after day 28 pw, or carcass parameters at slaughter. At day 7 pw, M11 piglets had 37% higher jejunal VH than CON piglets (P < 0.05) and S11 piglets had 28% higher ileal VH than S4 piglets (P < 0.05). M11 piglets had up to 150% higher ileal sucrase activity than M4, S4 and S11 piglets (P < 0.05) and 180% higher ileal maltase activity than S4 piglets (P < 0.05). In conclusion, M11 reduced the immediate negative effects of weaning, as it was associated with increased feed intake, growth, brush-border membrane enzyme activity and improved intestinal structure early pw. However, there were no carryover effects of any of the liquid supplements on growth or feed efficiency or carcass weight at slaughter.

2.
Artigo em Francês | MEDLINE | ID: mdl-39079843

RESUMO

The forehead is the cranial part of the forehead, and represents an important component of facial esthetics. The deformations linked to craniosynostoses are characterized by modifications in height, width, and angulation. Their surgical correction during childhood is based on well-established techniques of remodeling using resorbable osteosynthesis. Today, distraction and springs allow less invasive procedures with good outcomes. Sequellae mainly correspond to hypotrophies of the temporal region, corrected with fat grafting. The presence of a mutation increases the risk of reoperation in the first six years of life.

4.
Bone ; 141: 115600, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32822871

RESUMO

Syndromic craniosynostoses are defined by the premature fusion of one or more cranial and facial sutures, leading to skull vault deformation, and midfacial retrusion. More recently, mandibular shape modifications have been described in FGFR-related craniosynostoses, which represent almost 75% of the syndromic craniosynostoses. Here, further characterisation of the mandibular phenotype in FGFR-related craniosynostoses is provided in order to confirm mandibular shape modifications, as this could contribute to a better understanding of the involvement of the FGFR pathway in craniofacial development. The aim of our study was to analyse early mandibular morphology in a cohort of patients with FGFR2- (Crouzon and Apert) and FGFR3- (Muenke and Crouzonodermoskeletal) related syndromic craniosynostoses. We used a comparative geometric morphometric approach based on 3D imaging. Thirty-one anatomical landmarks and eleven curves with sliding semi-landmarks were defined to model the shape of the mandible. In total, 40 patients (12 with Crouzon, 12 with Apert, 12 with Muenke and 4 with Crouzonodermoskeletal syndromes) and 40 age and sex-matched controls were included (mean age: 13.7 months ±11.9). Mandibular shape differed significantly between controls and each patient group based on geometric morphometrics. Mandibular shape in FGFR2-craniosynostoses was characterized by open gonial angle, short ramus height, and high and prominent symphysis. Short ramus height appeared more pronounced in Apert than in Crouzon syndrome. Additionally, narrow inter-condylar and inter-gonial distances were observed in Crouzon syndrome. Mandibular shape in FGFR3-craniosynostoses was characterized by high and prominent symphysis and narrow inter-gonial distance. In addition, narrow condylar processes affected patients with Crouzonodermoskeletal syndrome. Statistical analysis of variance showed significant clustering of Apert and Crouzon, Crouzon and Muenke, and Apert and Muenke patients (p < 0.05). Our results confirm distinct mandibular shapes at early ages in FGFR2- (Crouzon and Apert syndromes) and FGFR3-related syndromic craniosynostoses (Muenke and Crouzonodermoskeletal syndromes) and reinforce the hypothesis of genotype-phenotype correspondence concerning mandibular morphology.


Assuntos
Acrocefalossindactilia , Disostose Craniofacial , Craniossinostoses , Acrocefalossindactilia/diagnóstico por imagem , Acrocefalossindactilia/genética , Disostose Craniofacial/diagnóstico por imagem , Disostose Craniofacial/genética , Humanos , Lactente , Mandíbula/diagnóstico por imagem , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Síndrome
5.
Anaesthesia ; 75(12): 1620-1625, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32520406

RESUMO

Lung ultrasound could facilitate the triage of patients with suspected COVID-19 infection admitted to the emergency room. We developed a predictive model for COVID-19 diagnosis based on lung ultrasound and clinical features. We used ultrasound to image the lung bilaterally at two anterior sites, one and two hands below each clavicle, and a posterolateral site that was the posterior transverse continuation from the lower anterior site. We studied 100 patients, 31 of whom had a COVID-19 positive reverse transcriptase polymerase chain reaction. A positive test was independently associated with: quick sequential organ failure assessment score ≥1; ≥3 B-lines at the upper site; consolidation and thickened pleura at the lower site; and thickened pleura line at the posterolateral site. The model discrimination was an area (95%CI) under the receiver operating characteristic curve of 0.82 (0.75-0.90). The characteristics (95%CI) of the model's diagnostic threshold, applied to the population from which it was derived, were: sensitivity, 97% (83-100%); specificity, 62% (50-74%); positive predictive value, 54% (41-98%); and negative predictive value, 98% (88-99%). This model may facilitate triage of patients with suspected COVID-19 infection admitted to the emergency room.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Serviço Hospitalar de Emergência/estatística & dados numéricos , Pulmão/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Adulto , Idoso , Área Sob a Curva , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/diagnóstico , Serviços Médicos de Emergência , Serviço Hospitalar de Emergência/organização & administração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Pandemias , Pleura/diagnóstico por imagem , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Triagem , Ultrassonografia
6.
Neurochirurgie ; 65(5): 210-215, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31586575

RESUMO

The vault of the skull is a region of the neurocranium formed by a process of membranous ossification. It consists of several bones: frontal bone, parietal bone, squamous part of the temporal bone, lamina ascendens of the sphenoid, and interparietal bone. The embryological origin of the bones of the skull vault is still the subject of controversy. This can be explained by the different animal models used for these purposes, but also by the various techniques applied to this problem. At all events, it seems that the cells of the neural crest generate some of the bones of the vault and that the others are derived from the mesoderm. This uncertainty should lead readers to be extremely cautious before using the presumptive maps published in the literature. Several tissues interact with osteo-progenitor cells: neural tube, surface ectoderm and dura mater. Analysis of genes in which mutations lead to abnormalities of the skull vault has partly revealed the molecular interactions. These are very complex and are the field of very numerous experimental investigations. In the relatively near future, we can hope to discover some of the molecular networks leading to the formation of these bony structures.


Assuntos
Crânio/crescimento & desenvolvimento , Animais , Feminino , Humanos , Crista Neural/crescimento & desenvolvimento , Gravidez , Crânio/anatomia & histologia , Crânio/embriologia
7.
Ann Chir Plast Esthet ; 64(5-6): 494-505, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31521419

RESUMO

Secondary surgeries for single craniosynostosis surgeries are mainly esthetic refinements rather than functional indications. However, cranioplasties for bone defects correction or insufficient corrections may be undertaken. Management of syndromic craniosynostoses usually requires multiple surgical interventions, the sequence of which might vary per the genetic mutation. It is commonplace to start with posterior vault expansion before age 6 months, then treat cerebellar tonsillar herniation by the age of twelve months, and delay fronto-facial monobloc advancement until at least 18-24 months of age. Ventricular shunting is preferably avoided or delayed. Failure to respect these guidelines can significantly complicate the subsequent management. Primary fronto-orbital advancement or early facial osteotomy type Le Fort3, may compromise the subsequent fronto-facial monobloc advancement. However, this salvage secondary monobloc may be undertaken in some instances despite previous anterior osteotomies with a higher morbidity.


Assuntos
Disostose Craniofacial/cirurgia , Craniossinostoses/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Reoperação , Adolescente , Criança , Pré-Escolar , Humanos , Lactente
8.
Rev Med Interne ; 40(9): 574-580, 2019 Sep.
Artigo em Francês | MEDLINE | ID: mdl-30904179

RESUMO

INTRODUCTION: Autoimmune acquired haemophilia is a rare autoimmune disease. The purpose of immunosuppressive therapy is to stop the production of autoantibodies that inhibit clotting factors VIII or IX. A corticosteroids-cyclophosphamide combination is recommanded as first-line therapy. From our experience at the University Hospital of Nîmes, we discuss the place of rituximab in the therapeutic arsenal. METHODS: We report a monocentric observational retrospective study. Our data are discussed in light of literature data, in particular cohorts EACH2 and SACHA. RESULTS: Eight patients (7 with FVIII anibodies) were consecutively included from 2005. The average age was 68.5 years with a male predominance (62.5%). Bleeding manifestations were usually spontaneous and superficial. A pathology, mostly autoimmune or neoplastic, was associated in 5/8 patients. A "by-pass" haemostatic treatment was prescribed for 3/8 patients. Rituximab was prescribed for 5/8 patients, three times as first-line therapy, and always associated with corticosteroids. Three patients received a cyclophosphamid/cortisone combination, two were treated exclusively with oral corticosteroids. Remission was obtained in all patients, without subsequent relapse. The average time to obtain remission under rituximab (after the first injection) was 32.5 days (10-143). The results observed in our series of patients are consistent with the data from the literature. CONCLUSIONS: Rituximab appears to be an effective and well-tolerated treatment for autoimmune acquired haemophilia. However, its place remains to be specified.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Hemofilia A/tratamento farmacológico , Hemofilia A/imunologia , Fatores Imunológicos/uso terapêutico , Rituximab/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
10.
Plant Phenomics ; 2019: 1671403, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33313522

RESUMO

GnpIS is a data repository for plant phenomics that stores whole field and greenhouse experimental data including environment measures. It allows long-term access to datasets following the FAIR principles: Findable, Accessible, Interoperable, and Reusable, by using a flexible and original approach. It is based on a generic and ontology driven data model and an innovative software architecture that uncouples data integration, storage, and querying. It takes advantage of international standards including the Crop Ontology, MIAPPE, and the Breeding API. GnpIS allows handling data for a wide range of species and experiment types, including multiannual perennial plants experimental network or annual plant trials with either raw data, i.e., direct measures, or computed traits. It also ensures the integration and the interoperability among phenotyping datasets and with genotyping data. This is achieved through a careful curation and annotation of the key resources conducted in close collaboration with the communities providing data. Our repository follows the Open Science data publication principles by ensuring citability of each dataset. Finally, GnpIS compliance with international standards enables its interoperability with other data repositories hence allowing data links between phenotype and other data types. GnpIS can therefore contribute to emerging international federations of information systems.

11.
Int J Oral Maxillofac Surg ; 47(4): 428-436, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29301676

RESUMO

Massive swelling of the tongue can occur after posterior fossa and craniofacial surgery. Several hypotheses have been proposed to explain the occurrence of such severe postoperative macroglossia, but this phenomenon is still poorly understood. Severe postoperative macroglossia can be a life-threatening condition due to upper airway obstruction. Three cases of severe postoperative macroglossia that occurred after cervical spine, craniofacial, and posterior fossa surgical procedures are reported here. These cases required specialized maxillofacial management and a prolonged stay in the intensive care unit. Causal factors involved in this condition are reported, in order to highlight appropriate prevention and treatment options adapted to the management of paediatric patients. An overview of the current literature on severe postoperative macroglossia in paediatric populations is also provided.


Assuntos
Vértebras Cervicais/cirurgia , Fossa Craniana Posterior/cirurgia , Anormalidades Craniofaciais/cirurgia , Macroglossia/etiologia , Macroglossia/terapia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Adolescente , Criança , Feminino , Humanos , Lactente , Masculino
12.
Rev Med Interne ; 39(2): 78-83, 2018 Feb.
Artigo em Francês | MEDLINE | ID: mdl-29221884

RESUMO

INTRODUCTION: Giant cell arteritis is a large-vessels vasculitis, which treatment consists in a slowly-tappered steroid-therapy. Immunosuppressive agents are sometimes used in case of steroid-dependance. We have conducted an observationnal retrospective study including patients treated with tocilizumab for a giant cell arteritis or an aortitis in the internal medicine department at the Nîmes University Hospital. RESULTS: Eleven patients were included between 2011 and 2016, who had been treated only with prednisone. Tocilizumab was used because of steroid-dependance for nine patients, delirium under steroids for one patient and unefficiency of steroids for an other patient. Infusions of tocilizumab, administred monthly at 8mg/kg, led to clinical and biological remission for all patients. Consequently, prednisone was tappered under 10mg/d for ten patients after six months of treatment with tocilizumab. Eight cases of non-severe infection were reported; also two cases of dyslipidemia, one case of prurit and one case of moderate neutropenia. Two relapses were observed after the end of treatment, in patients treated with less than twelve infusions. CONCLUSION: Tocilizumab could be efficient and well-tolerated in steroid-dependent giant cell arteritis and aortitis. The modalities of its use remain to be precised.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Arterite de Células Gigantes/tratamento farmacológico , Glucocorticoides/uso terapêutico , Prednisona/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Feminino , França , Glucocorticoides/efeitos adversos , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
13.
Int J Obes (Lond) ; 41(10): 1539-1546, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28611394

RESUMO

BACKGROUND/OBJECTIVES: Characterisation of the adipocyte cellular lineage is required for a better understanding of white adipose tissue homoeostasis and expansion. Although several studies have focused on the phenotype of the most immature adipocyte progenitors, very few tools exist to identify committed cells. In haematopoiesis, the CD38 ectoenzyme is largely used to delineate various stages of stem cell lineage commitment. We hypothesise that this marker could be used to identify committed preadipocytes. METHODS: Complementary strategies including flow cytometry, cell-sorting approaches, immunohistochemistry and primary cultures of murine adipose progenitors isolated from different fat pads of control or high-fat diet exposed C57BL/6 J mice were used to determine the molecular expression profile, proliferative and differentiation potentials of adipose progenitors expressing the CD38 molecule. RESULTS: We demonstrate here that a subpopulation of CD45- CD31- CD34+ adipose progenitors express the cell surface protein CD38. Using a cell-sorting approach, we found that native CD45- CD31- CD34+ CD38+ (CD38+) adipose cells expressed lower CD34 mRNA and protein levels and higher levels of adipogenic genes such as Pparg, aP2, Lpl and Cd36 than did the CD45- CD31- CD34+ CD38- (CD38-) population. When cultivated, CD38+ cells displayed reduced proliferative potential, assessed by BrdU incorporation and colony-forming unit assays, and greater adipogenic potential. In vitro, both CD38 mRNA and protein levels were increased during adipogenesis and CD38- cells converted into CD38+ cells when committed to the adipogenic differentiation programme. We also found that obesity development was associated with an increase in the number of CD38+ adipose progenitors, this effect being more pronounced in intra-abdominal than in subcutaneous fat, suggesting a higher rate of adipocyte commitment in visceral depots. CONCLUSIONS: Together, these data demonstrate that CD38 represents a new marker that identifies committed preadipocytes as CD45- CD31- CD34low CD38+ cells.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Adipócitos/citologia , Tecido Adiposo Branco/citologia , Diferenciação Celular , Linhagem da Célula , Glicoproteínas de Membrana/metabolismo , Obesidade/metabolismo , Adipócitos/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Biomarcadores/metabolismo , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Citometria de Fluxo , Imuno-Histoquímica , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/fisiopatologia , Células Estromais/citologia
14.
Ann Chir Plast Esthet ; 61(5): 408-419, 2016 Oct.
Artigo em Francês | MEDLINE | ID: mdl-27692993

RESUMO

The complexity of treatment of faciocraniosynostosis justifies the treatment in a reference center for rare diseases. The growth disturbances in the skull and face being variable according to the type of mutation in the FGFr (Crouzon, Pfeiffer, Apert), the strategy is adapted to the phenotype according to the following principles: posterior expansion with or without distraction around 6 months to limit the descent of the cerebellum tonsils and to prevent the turricephalic development; fronto-facial monobloc advancement with internal distraction around the age of 18 months in case of severe exorbitism or breathing impairment. The dissociated strategy (fronto-orbital advancement first, followed by facial osteotomy of Le Fort 3 type). The growing evolution dictates the sequence of subsequent surgeries according to the monitoring of intracranial pressure by fundus examination and of the respiration by polysomnography. Le Fort 3 and transversal maxillary distraction may be repeated if necessary. Orthognathic surgery is almost always compulsory after the age of 14, before the aesthetic refinements which can be undertaken ultimately (rhinoplasty, genioplasty, canthopexies, fat grafting…).


Assuntos
Disostose Craniofacial/cirurgia , Craniossinostoses/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Criança , Disostose Craniofacial/diagnóstico por imagem , Craniossinostoses/diagnóstico por imagem , Craniotomia , Humanos , Imageamento Tridimensional , Osteogênese por Distração , Cirurgia Assistida por Computador
15.
J Control Release ; 228: 132-140, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-26959846

RESUMO

Intracellular drug delivery by nanoparticles is often hampered by their endosomal entrapment followed by their degradation in the lysosomal compartment and/or exocytosis. Here, we show that internalization and endosomal escape of cargoes in a cationized natural nanocarrier, high-density lipoprotein (HDL), can be controlled in a pH-dependent manner through stable complexation with a membranolytic anionic block polymer. A genetically and chemically cationized form of HDL (catHDL) is prepared for the first time by both genetic fusion with YGRKKRRQRRR peptide and incorporation of 1,2-dioleoyloxy-3-(trimethylammonium)propane. Upon addition of poly(ethylene glycol)-block-poly(propyl methacrylate-co-methacrylic acid) (PA), catHDL yields inhibition of internalization at neutral pH and its subsequent recovery at mildly acidic pH. catHDL forms a stable discoidal-shape complex with PA (catHDL/PA) (ca. 50 nm in diameter), even in the presence of serum. Significant enhancement of endosomal escape of a catHDL component is observed after a 1-h treatment of human cancer cells with catHDL/PA. Doxorubicin and curcumin, fluorescent anti-cancer drugs, encapsulated into catHDL/PA are also translocated outside of endosomes, compared with that into catHDL, and their cytotoxicities are enhanced inside the cells. These data suggest that catHDL/PA may have a potential benefit to improve the cellular delivery and endosomal escape of therapeutics under mildly acidic conditions such as in tumor tissues.


Assuntos
Antineoplásicos/administração & dosagem , Preparações de Ação Retardada/química , Ácidos Graxos Monoinsaturados/química , Lipoproteínas HDL/química , Ácidos Polimetacrílicos/química , Compostos de Amônio Quaternário/química , Sequência de Aminoácidos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Curcumina/administração & dosagem , Curcumina/farmacocinética , Curcumina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Endossomos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Polietilenoglicóis/química , Proteínas Recombinantes de Fusão/química
17.
Ann Chir Plast Esthet ; 59(6): 585-91, 2014 Dec.
Artigo em Francês | MEDLINE | ID: mdl-25303936

RESUMO

In craniofacial malformations, the nose is variably affected: in its location, its shape or by lack of development. In this short chapter, some of the common problems encountered by the specialized teams are summarized. Craniofacial astronomies can modify the skeleton of the nose during growth, sometime at an early age. However, most rhinoplasties are performed at adulthood. The nasal pyramid may present deformations that produce functional and aesthetics impairment that should be treated when necessary. Respiratory problems should be recognized as early as possible and treated in priority.


Assuntos
Anormalidades Craniofaciais/cirurgia , Estética , Nariz/anormalidades , Rinoplastia/métodos , Adolescente , Adulto , Cartilagem/transplante , Criança , Anormalidades Craniofaciais/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Imageamento Tridimensional , Lactente , Osteotomia de Le Fort/métodos , Reoperação , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
J Steroid Biochem Mol Biol ; 136: 229-32, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23026511

RESUMO

Ultra violet (UV) irradiation, in particular UVB, is the single most important carcinogen for skin tumor formation. UVB induces genetic mutations and immune suppression, which lead to abnormal cell proliferation and eventually tumor formation. Previously studies from our group and others demonstrated that both global and epidermal specific VDR knock out mice are predisposed to either chemical (DMBA)- or long-term UVB-induced skin tumor formation, paralleled by an increase in ß-catenin signaling. Using primary cultured human keratinocytes, we further demonstrated that 1,25(OH)2-dihydroxyvitamin D3 (1,25(OH)2D3) suppresses cyclin D1 and Gli1 which are regulated by ß-catenin/TCF signaling and have a critical role in epidermal carcinogenesis. Blockage of VDR by siRNA resulted in hyperproliferation of keratinocytes, and increased expression of cyclin D1 and Gli1. In addition, we also showed that 1,25(OH)2D3/VDR directly regulates transcriptional activity of ß-catenin/TCF signaling using the -catenin reporter TopGlow. Using K14 driven tamoxifen-induced cre recombinase to delete both VDR and ß-catenin in keratinocytes of mice following the first hair follicle cycle, we found that ablation of epidermal specific ß-catenin cannot rescue VDR null mice from UVB-induced skin tumor formation. Further study using VDR or ß-catenin single null mice is necessary to compare with the data from double null mice. This article is part of a Special Issue entitled 'Vitamin D Workshop'.


Assuntos
Calcitriol/farmacologia , Receptores de Calcitriol/metabolismo , Transdução de Sinais/fisiologia , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos , beta Catenina/metabolismo , Animais , Calcitriol/metabolismo , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/patologia , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/metabolismo , Neoplasias Induzidas por Radiação/prevenção & controle , Receptores de Calcitriol/antagonistas & inibidores , Receptores de Calcitriol/deficiência , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/metabolismo , beta Catenina/deficiência , beta Catenina/fisiologia
20.
Childs Nerv Syst ; 28(9): 1465-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22872263

RESUMO

AIM AND SCOPE: The developmental genetics and the biomechanics of sutures are well-studied topics, while their microanatomy is still imperfectly known. Here, we aim to investigate the structure of skull vault sutures using a high-resolution imaging device. MATERIAL AND METHODS: We used synchrotron X-ray microtomography in order to obtain high-resolution images of skull vault sutures from an extant mammal (the mouse Mus musculus) and from an extinct fish (the placoderm Compagopiscis croucheri). We used segmentation and 3D reconstruction softwares in order to reveal the microanatomy of sutures in these species. RESULTS: The high-resolution images allowed us to study the distribution of osteocytes, the organisation of vascular canals, the shapes of the suture borders, the insertion of Sharpey's fibres, the bone growth lines and the structure of the soft tissues surrounding the sutures. CONCLUSION: Synchrotron imaging provides new perspectives for the study of the normal microanatomy of sutures. The submicronic resolution of the synchrotron scans gives access to the 3D organisation of structures that were previously only known in 2D, even in normal sutures. The description of anatomical entities such as vascular canals and Sharpey's fibres in abnormally fused sutures would be of interest in the understanding of craniosynostoses.


Assuntos
Suturas Cranianas/diagnóstico por imagem , Ossos Faciais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Animais , Animais Recém-Nascidos , Desenvolvimento Ósseo/fisiologia , Colágeno/metabolismo , Suturas Cranianas/crescimento & desenvolvimento , Ossos Faciais/crescimento & desenvolvimento , Imageamento Tridimensional , Camundongos
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