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Gkourogianni A, Andrew M, Tyzinski L, Crocker M, Douglas J, Dunbar N, Fairchild J, Funari MFA, Heath KE, Jorge AAL, Kurtzman T, LaFranchi S, Lalani S, Lebl J, Lin Y, Los E, Newbern D, Nowak C, Olson M, Popovic J, Průhová Š, Elblova L, Quintos JB, Segerlund E, Sentchordi L, Shinawi M, Stattin EL, Swartz J, del Angel AG, Cuéllar SD, Hosono H, Sanchez-Lara PA, Hwa V, Baron J, Nilsson O, Dauber A. Clinical Characterization of Patients With Autosomal Dominant Short Stature due to Aggrecan Mutations. J Clin Endocrinol Metab 2017; 102:460-469. [PMID: 27870580 PMCID: PMC5413162 DOI: 10.1210/jc.2016-3313] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/18/2016] [Indexed: 12/22/2022]
Abstract
CONTEXT Heterozygous mutations in the aggrecan gene (ACAN) cause autosomal dominant short stature with accelerated skeletal maturation. OBJECTIVE We sought to characterize the phenotypic spectrum and response to growth-promoting therapies. PATIENTS AND METHODS One hundred three individuals (57 females, 46 males) from 20 families with autosomal dominant short stature and heterozygous ACAN mutations were identified and confirmed using whole-exome sequencing, targeted next-generation sequencing, and/or Sanger sequencing. Clinical information was collected from the medical records. RESULTS Identified ACAN variants showed perfect cosegregation with phenotype. Adult individuals had mildly disproportionate short stature [median height, -2.8 standard deviation score (SDS); range, -5.9 to -0.9] and a history of early growth cessation. The condition was frequently associated with early-onset osteoarthritis (12 families) and intervertebral disc disease (9 families). No apparent genotype-phenotype correlation was found between the type of ACAN mutation and the presence of joint complaints. Childhood height was less affected (median height, -2.0 SDS; range, -4.2 to -0.6). Most children with ACAN mutations had advanced bone age (bone age - chronologic age; median, +1.3 years; range, +0.0 to +3.7 years). Nineteen individuals had received growth hormone therapy with some evidence of increased growth velocity. CONCLUSIONS Heterozygous ACAN mutations result in a phenotypic spectrum ranging from mild and proportionate short stature to a mild skeletal dysplasia with disproportionate short stature and brachydactyly. Many affected individuals developed early-onset osteoarthritis and degenerative disc disease, suggesting dysfunction of the articular cartilage and intervertebral disc cartilage. Additional studies are needed to determine the optimal treatment strategy for these patients.
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Martinez E, Ruiz-Pinero M, de Lera M, Baron J, Pedraza MI, Guerrero-Peral AL. [Clinical characteristics of vestibular migraine: considerations in a series of 41 patients]. Rev Neurol 2017; 64:1-6. [PMID: 28000906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
INTRODUCTION After years of debate about its being approached from headaches and its denomination, vestibular migraine has recently been included in the research appendix of the 3rd edition of the International Headache Classification. AIM To analyse the characteristics of a series of patients with vestibular migraine who visited because of headaches. PATIENTS AND METHODS Our sample consisted of patients who were attended in a headache unit between January 2014 and December 2015. The demographic variables and the characteristics of both migraine and vestibular symptoms were considered, and cases with other otorhinolaryngological conditions were excluded. RESULTS The sample was finally made up of 41 patients (11 males, 30 females) with a mean age of 31.8 ± 13.3 years at the time they were included in the study. Sixteen patients (39%) met criteria for chronic migraine and two (4.9%) presented visual auras. The vestibular symptoms were considered severe in eight cases (19.5%) and occurred in 74.6% of the migraine attacks. Vertigo was described as internal in 18 cases (43.9%), external in 22 (53.7%) and mixed in one case (2.4%). The most frequent symptom was positional vertigo (n = 25; 61%), followed by that induced by head movements (n = 18; 43.9%) and spontaneous (n = 15; 36.6%). Accompanying symptoms included tinnitus (n = 12; 29.3%) and a feeling of fullness in the ear (n = 8; 19.5%). CONCLUSION It is not uncommon to identify symptoms consistent with vestibular migraine in patients who visit a headache unit; they are patients whose day-to-day activities are not usually affected by their vertigo.
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Cunha BA, Baron J, Cunha CB. Once daily high dose tigecycline - pharmacokinetic/pharmacodynamic based dosing for optimal clinical effectiveness: dosing matters, revisited. Expert Rev Anti Infect Ther 2016; 15:257-267. [DOI: 10.1080/14787210.2017.1268529] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Jee YH, Sowada N, Markello TC, Rezvani I, Borck G, Baron J. BRF1 mutations in a family with growth failure, markedly delayed bone age, and central nervous system anomalies. Clin Genet 2016; 91:739-747. [PMID: 27748960 DOI: 10.1111/cge.12887] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/06/2016] [Accepted: 10/10/2016] [Indexed: 12/20/2022]
Abstract
Linear growth failure can be caused by many different genetic abnormalities. In many cases, the genetic defect affects not only the growth plate, causing short stature but also other organs/tissues causing additional clinical abnormalities. A 10-year old boy was evaluated for impaired postnatal linear growth (height 113.3 cm, -4.6 SDS), a bone age that was delayed by 5 years, dysmorphic facies, cognitive impairment, and central nervous system anomalies. His younger brother, presented only with growth failure at 10 months of age. Exome sequencing identified compound heterozygous variants in the gene encoding RNA polymerase III transcription initiation factor 90 kDa subunit (BRF1) in both affected siblings: a missense mutation (c.875 C > G:p.P292R) and a frameshift mutation (c.551delG:p.C184Sfs). The frameshift mutation is expected to lead to nonsense-mediated mRNA decay (NMD) and/or to protein truncation. Expression of BRF1 with the P292R missense mutation failed to rescue yeast lacking BRF1. The findings confirm a previous report showing that biallelic mutations in BRF1 cause cerebellar-facial-dental syndrome. Our findings also help define the growth phenotype, indicating that the linear growth failure can become clinically evident before the neurological abnormalities and that a severely delayed bone age may serve as a diagnostic clue.
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Lui JC, Garrison P, Nguyen Q, Ad M, Keembiyehetty C, Chen W, Jee YH, Landman E, Nilsson O, Barnes KM, Baron J. EZH1 and EZH2 promote skeletal growth by repressing inhibitors of chondrocyte proliferation and hypertrophy. Nat Commun 2016; 7:13685. [PMID: 27897169 PMCID: PMC5477487 DOI: 10.1038/ncomms13685] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 10/25/2016] [Indexed: 12/16/2022] Open
Abstract
Histone methyltransferases EZH1 and EZH2 catalyse the trimethylation of histone H3 at lysine 27 (H3K27), which serves as an epigenetic signal for chromatin condensation and transcriptional repression. Genome-wide associated studies have implicated EZH2 in the control of height and mutations in EZH2 cause Weaver syndrome, which includes skeletal overgrowth. Here we show that the combined loss of Ezh1 and Ezh2 in chondrocytes severely impairs skeletal growth in mice. Both of the principal processes underlying growth plate chondrogenesis, chondrocyte proliferation and hypertrophy, are compromised. The decrease in chondrocyte proliferation is due in part to derepression of cyclin-dependent kinase inhibitors Ink4a/b, while ineffective chondrocyte hypertrophy is due to the suppression of IGF signalling by the increased expression of IGF-binding proteins. Collectively, our findings reveal a critical role for H3K27 methylation in the regulation of chondrocyte proliferation and hypertrophy in the growth plate, which are the central determinants of skeletal growth.
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Nilsson O, Isoherranen N, Guo MH, Lui JC, Jee YH, Guttmann-Bauman I, Acerini C, Lee W, Allikmets R, Yanovski JA, Dauber A, Baron J. Accelerated Skeletal Maturation in Disorders of Retinoic Acid Metabolism: A Case Report and Focused Review of the Literature. Horm Metab Res 2016; 48:737-744. [PMID: 27589347 PMCID: PMC5534175 DOI: 10.1055/s-0042-114038] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Nutritional excess of vitamin A, a precursor for retinoic acid (RA), causes premature epiphyseal fusion, craniosynostosis, and light-dependent retinopathy. Similarly, homozygous loss-of-function mutations in CYP26B1, one of the major RA-metabolizing enzymes, cause advanced bone age, premature epiphyseal fusion, and craniosynostosis. In this paper, a patient with markedly accelerated skeletal and dental development, retinal scarring, and autism-spectrum disease is presented and the role of retinoic acid in longitudinal bone growth and skeletal maturation is reviewed. Genetic studies were carried out using SNP array and exome sequencing. RA isomers were measured in the patient, family members, and in 18 age-matched healthy children using high-performance liquid chromatography coupled to tandem mass spectrometry. A genomic SNP array identified a novel 8.3 megabase microdeletion on chromosome 10q23.2-23.33. The 79 deleted genes included CYP26A1 and C1, both major RA-metabolizing enzymes. Exome sequencing did not detect any variants that were predicted to be deleterious in the remaining alleles of these genes or other known retinoic acid-metabolizing enzymes. The patient exhibited elevated plasma total RA (16.5 vs. 12.6±1.5 nM, mean±SD, subject vs. controls) and 13-cisRA (10.7 nM vs. 6.1±1.1). The findings support the hypothesis that elevated RA concentrations accelerate bone and dental maturation in humans. CYP26A1 and C1 haploinsufficiency may contribute to the elevated retinoic acid concentrations and clinical findings of the patient, although this phenotype has not been reported in other patients with similar deletions, suggesting that other unknown genetic or environmental factors may also contribute.
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Pakhale S, Baron J, Armstrong M, Tasca G, Gaudet E, Aaron SD, Cameron W, Balfour L. Lost in translation? How adults living with Cystic Fibrosis understand treatment recommendations from their healthcare providers, and the impact on adherence to therapy. PATIENT EDUCATION AND COUNSELING 2016; 99:1319-1324. [PMID: 27036082 DOI: 10.1016/j.pec.2016.03.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/16/2016] [Accepted: 03/22/2016] [Indexed: 06/05/2023]
Abstract
OBJECTIVE This study builds on the limited research documenting Cystic Fibrosis (CF) patients' understanding of treatment recommendations and how this may impact adherence to therapy. METHODS We surveyed adults with CF and their healthcare professional (HCP) to capture treatment recommendations provided by the HCP, and patients' knowledge, and frequency of performance, of these recommendations. We classified CF participants' understanding of treatment recommendations (correct/incorrect) as compared to the actual recommendations made by the HCP. We computed CF participants' adherence in relation to HCP treatment recommendations and to their own understanding of treatment recommendations (adherent/non-adherent). RESULTS Complete HCP and patient data were available for 42 participants. The recommended treatment frequency was correctly understood by 0%-87.8% of CF participants. Adherence to HCP treatment recommendations ranged from 0 to 68.3% (mean 45.4%±21.5), and rates were low (<33%) for acapella, percussion/postural drainage, tobramycin nebulization and insulin. Participants' adherence was greater when calculated in relation to participants' understanding of treatment recommendations (62.4%±25.1) than when calculated in relation to actual HCP treatment recommendations (45.4%±21.5%) (p=0.009). CONCLUSION AND PRACTICE IMPLICATIONS Adults with CF misunderstand treatment recommendations; this likely affects treatment adherence. Interventions to ensure HCPs use effective communication strategies are needed.
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Cunha BA, Baron J. The pharmacokinetic basis of oral valacyclovir treatment of herpes simplex virus (HSV) or varicella zoster virus (VZV) meningitis, meningoencephalitis or encephalitis in adults. J Chemother 2016; 29:122-125. [DOI: 10.1179/1973947815y.0000000065] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Baron J, Menon M, Hare RB, Lund I, Mohr A, Rondeau C, Syta M, Celotto K, Iyer SP, Bhat S, Hernandez-Ilizaliturri FJ. Efficacy and safety of examethasone, high dose cytarabine, and carboplatin (DHAC) with and without rituximab (R) as a salvage regimen for relapsed/refractory (R/R) lymphoma. J Clin Oncol 2016. [DOI: 10.1200/jco.2016.34.15_suppl.e19023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Jee YH, Lebenthal Y, Chaemsaithong P, Yan G, Peran I, Wellstein A, Romero R, Baron J. Midkine and Pleiotrophin Concentrations in Amniotic Fluid in Healthy and Complicated Pregnancies. PLoS One 2016; 11:e0153325. [PMID: 27089523 PMCID: PMC4835047 DOI: 10.1371/journal.pone.0153325] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 03/28/2016] [Indexed: 01/14/2023] Open
Abstract
Background Midkine (MDK) and pleiotrophin (PTN) are heparin-binding growth factors that, in rodents, are highly expressed in early life and decrease to undetectable levels by adulthood. The potential roles of MDK and PTN in human growth and development are not completely elucidated. Method and Findings To delineate the role of MDK and PTN in human development, we developed high sensitivity assays to measure their concentrations in amniotic fluid (AF) at various gestational ages in both healthy and complicated pregnancies. We found that both of these growth factors could be readily measured in AF and that the concentrations were higher than most cytokines previously reported in AF. Conclusion The concentration of MDK but not that of PTN declined with gestational age. Both MDK and PTN concentrations were found to be lower in pregnancies that were complicated by chorioamnionitis at term, raising the possibility that these growth factors might be useful as markers for infection.
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Baron J, El-Chaar G. Hypertonic Saline for the Treatment of Bronchiolitis in Infants and Young Children: A Critical Review of the Literature. J Pediatr Pharmacol Ther 2016; 21:7-26. [PMID: 26997926 DOI: 10.5863/1551-6776-21.1.7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bronchiolitis, an infection of the lower respiratory tract, is the leading cause of infant and child hospitalization in the United States. Therapeutic options for management of bronchiolitis are limited. Hypertonic saline inhalation therapy has been studied in numerous clinical trials with mixed results. In 2014, the American Academy of Pediatrics (AAP) published updated guidelines on the diagnosis and management of bronchiolitis, which include new recommendations on the use of hypertonic saline. We reviewed all published clinical trials mentioned in the 2014 AAP guidelines, as well as additional trials published since the guidelines, and critically evaluated each trial to determine efficacy, safety, and expectations of hypertonic saline inhalation therapy. A total of 2682 infants were studied over the course of 22 clinical trials. Nine trials were carried out in the outpatient/clinic/emergency department and 13 in the inpatient setting. We agree with the AAP guidelines regarding the recommendation to use nebulized hypertonic saline for infants hospitalized with bronchiolitis, with the expectation of reducing bronchiolitis scores and length of stay when it is expected to last more than 72 hours. However, we also believe there might be an advantage for hypertonic saline in reducing admission rates from the emergency department, based on close examination of the results of recent trials. This review also highlights important gaps in the available literature that need to be addressed in order to define the role of inhaled hypertonic saline therapy.
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Jee YH, Sadowski SM, Celi FS, Xi L, Raffeld M, Sacks DB, Remaley AT, Wellstein A, Kebebew E, Baron J. Increased Pleiotrophin Concentrations in Papillary Thyroid Cancer. PLoS One 2016; 11:e0149383. [PMID: 26914549 PMCID: PMC4767803 DOI: 10.1371/journal.pone.0149383] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 02/01/2016] [Indexed: 01/21/2023] Open
Abstract
Background Thyroid nodules are common, and approximately 5% of these nodules are malignant. Pleiotrophin (PTN) is a heparin-binding growth factor which is overexpressed in many cancers. The expression of PTN in papillary thyroid cancer (PTC) is unknown. Method and Findings 74 subjects (age 47 ± 12 y, 15 males) who had thyroidectomy with a histological diagnosis: 79 benign nodules and 23 PTCs (10 classic, 6 tall cell, 6 follicular variant and 1 undetermined). Fine-needle aspiration (FNA) samples were obtained ex vivo from surgically excised tissue and assayed for PTN and thyroglobulin (Tg). Immunohistochemistry (IHC) was performed on tissue sections. In FNA samples, PTN concentration normalized to Tg was significantly higher in PTC than in benign nodules (16 ± 6 vs 0.3 ± 0.1 ng/mg, p < 0.001). In follicular variant of PTC (n = 6), the PTN/Tg ratio was also higher than in benign nodules (1.3 ± 0.6 vs 0.3 ± 0.1 ng/mg, P < 0.001, respectively). IHC showed cytoplasmic localization of PTN in PTC cells. Conclusion In ex vivo FNA samples, the PTN to thyroglobulin ratio was higher in PTCs, including follicular variant PTC, than in benign thyroid nodules. The findings raise the possibility that measurement of the PTN to Tg ratio may provide useful diagnostic and/or prognostic information in the evaluation of thyroid nodules.
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Vidal A, Rinaldo M, Brochard P, Baron J, Verdun-Esquer C. Grossesse et travail au CHU de Bordeaux : étude comparative de la fréquence des principales complications de la grossesse du personnel (hors personnel médical et de recherche) par rapport à la population générale. ARCH MAL PROF ENVIRO 2016. [DOI: 10.1016/j.admp.2015.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Likus W, Gruszczyńska K, Markowski J, Machnikowska-Sokołowska M, Olczak Z, Bajor G, Los MJ, Baron J. Correlations between selected parameters of nasal cavity in neonates and young infants - computed tomography study. Folia Morphol (Warsz) 2015; 75:334-340. [PMID: 26711652 DOI: 10.5603/fm.a2015.0128] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 11/13/2015] [Indexed: 11/25/2022]
Abstract
BACKGROUND Correlations between selected metric parameters of the nasal cavity and nasopharynx in children without atresia may be useful for anticipating probable dimensions of this region in living subjects, in terms of changes with age. MATERIALS AND METHODS One hundred and eighty children, age range 0-3 years, were divided into five age groups, and measurements of 18 distances between structures of nasal cavity and nosopharynx were performed on computed tomography scans. Correlation coefficients and relations between parameters have been determined. RESULTS Our study confirmed the existence of statistically significant correlations between linear dimensions within nasal cavity in children. The analysis demon-strated that for the values of following indexes: nasal septum length/piriform aperture width, and maximum length of the nasal septum/posterior nares width no statistically significant differences have been noted between age groups of children. All correlations have been positive. No statistically significant differences have been noted between the maximum width of the vomer and osseous parameters measured, both in the anterior and posterior part of the nasal cavity, and nasal septum length. CONCLUSIONS The size of posterior nares changed with age in children by a constant value. So far, no such an analysis has been carried out assessing potential correlations between linear dimensions for the entire nasal cavity, nasopharynx, length of the nasal septum in children, as well as proportions of individual linear dimensions of the anatomical structures analysed, in various age groups.
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Baron J, Sävendahl L, De Luca F, Dauber A, Phillip M, Wit JM, Nilsson O. Short and tall stature: a new paradigm emerges. Nat Rev Endocrinol 2015; 11:735-46. [PMID: 26437621 PMCID: PMC5002943 DOI: 10.1038/nrendo.2015.165] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
In the past, the growth hormone (GH)-insulin-like growth factor 1 (IGF-1) axis was often considered to be the main system that regulated childhood growth and, therefore, determined short stature and tall stature. However, findings have now revealed that the GH-IGF-1 axis is just one of many regulatory systems that control chondrogenesis in the growth plate, which is the biological process that drives height gain. Consequently, normal growth in children depends not only on GH and IGF-1 but also on multiple hormones, paracrine factors, extracellular matrix molecules and intracellular proteins that regulate the activity of growth plate chondrocytes. Mutations in the genes that encode many of these local proteins cause short stature or tall stature. Similarly, genome-wide association studies have revealed that the normal variation in height seems to be largely due to genes outside the GH-IGF-1 axis that affect growth at the growth plate through a wide variety of mechanisms. These findings point to a new conceptual framework for understanding short and tall stature that is centred not on two particular hormones but rather on the growth plate, which is the structure responsible for height gain.
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Jee YH, Celi FS, Sampson M, Sacks DB, Remaley AT, Kebebew E, Baron J. Midkine concentrations in fine-needle aspiration of benign and malignant thyroid nodules. Clin Endocrinol (Oxf) 2015; 83:977-84. [PMID: 25411136 PMCID: PMC5532878 DOI: 10.1111/cen.12676] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 10/18/2014] [Accepted: 11/17/2014] [Indexed: 01/21/2023]
Abstract
CONTEXT The primary preoperative method for distinguishing malignant from benign thyroid nodules is fine-needle aspiration (FNA) cytology, but it is frequently inconclusive. Midkine (MDK) is a heparin-binding growth factor, which is overexpressed in papillary thyroid carcinoma (PTC). OBJECTIVE We measured MDK concentrations in FNA samples from benign and malignant thyroid nodules to explore the possibility that MDK measurement might aid in the evaluation of thyroid nodules. DESIGN 35 subjects underwent preoperative FNA of 45 thyroid nodules, followed by thyroidectomy, providing a histological diagnosis. FNA needle contents were first expressed for cytology, and then, the needle was washed with buffer for immunoassay. In 46 subjects without preoperative FNA samples, FNA was performed ex vivo on 62 nodules within surgically excised thyroid tissue. MEASUREMENTS MDK was measured using a high-sensitivity sandwich ELISA and normalized to thyroglobulin (Tg) concentration in the sample to adjust for tissue content in the aspirate. RESULTS The MDK/Tg ratio was higher in 18 PTCs than in 87 benign nodules (204 ± 106 vs 1·2 ± 0·3 ng/mg, mean ± SEM, P < 0·001). Using a threshold of 10 ng/mg, the sensitivity and specificity of the MDK/Tg ratio for diagnosis of PTC were 67% and 99%, respectively. All follicular variant PTCs had a MDK/Tg ratio <10 ng/mg. CONCLUSIONS The findings indicate that, in FNA samples, the MDK/Tg ratio in PTC is greater than in benign thyroid nodules, raising the possibility that this approach might provide adjunctive diagnostic or prognostic information to complement existing approaches.
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Koide H, Holmbeck K, Lui JC, Guo XC, Driggers P, Chu T, Tatsuno I, Quaglieri C, Kino T, Baron J, Young MF, Robey PG, Segars JH. Mice Deficient in AKAP13 (BRX) Are Osteoporotic and Have Impaired Osteogenesis. J Bone Miner Res 2015; 30:1887-95. [PMID: 25892096 PMCID: PMC4590282 DOI: 10.1002/jbmr.2534] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 04/03/2015] [Accepted: 04/15/2015] [Indexed: 01/23/2023]
Abstract
Mechanical stimulation is crucial to bone growth and triggers osteogenic differentiation through a process involving Rho and protein kinase A. We previously cloned a gene (AKAP13, aka BRX) encoding a protein kinase A-anchoring protein in the N-terminus, a guanine nucleotide-exchange factor for RhoA in the mid-section, coupled to a carboxyl region that binds to estrogen and glucocorticoid nuclear receptors. Because of the critical role of Rho, estrogen, and glucocorticoids in bone remodeling, we examined the multifunctional role of Akap13. Akap13 was expressed in bone, and mice haploinsufficient for Akap13 (Akap13(+/-)) displayed reduced bone mineral density, reduced bone volume/total volume, and trabecular number, and increased trabecular spacing; resembling the changes observed in osteoporotic bone. Consistent with the osteoporotic phenotype, Colony forming unit-fibroblast numbers were diminished in Akap13(+/-) mice, as were osteoblast numbers and extracellular matrix production when compared to control littermates. Transcripts of Runx2, an essential transcription factor for the osteogenic lineage, and alkaline phosphatase (Alp), an indicator of osteogenic commitment, were both reduced in femora of Akap13(+/-) mice. Knockdown of Akap13 reduced levels of Runx2 and Alp transcripts in immortalized bone marrow stem cells. These findings suggest that Akap13 haploinsufficient mice have a deficiency in early osteogenesis with a corresponding reduction in osteoblast number, but no impairment of mature osteoblast activity.
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Win A, Reece J, Dowty J, Buchanan D, Clendenning M, Young J, Cleary S, Cotterchio M, Macrae F, Baron J, Le Marchand L, Casey G, Haile R, Newcomb P, Thibodeau S, Hopper J, Gallinger S, Winship I, Lindor N, Jenkins M. 1054 Risk of extracolonic cancers for people with biallelic and monoallelic mutations in MUTYH. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)30480-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
PURPOSE OF REVIEW Recent basic studies have yielded important new insights into the molecular mechanisms that regulate growth locally. Simultaneously, clinical studies have identified new molecular defects that cause growth failure and overgrowth, and genome-wide association studies have elucidated the genetic basis for normal human height variation. RECENT FINDINGS The Hippo pathway has emerged as one of the major mechanisms controlling organ size. In addition, an extensive genetic program has been described that allows rapid body growth in the fetus and infant but then causes growth to slow with age in multiple tissues. In human genome-wide association studies, hundreds of loci associated with adult stature have been identified; many appear to involve genes that function locally in the growth plate. Clinical genetic studies have identified a new genetic abnormality, microduplication of Xq26.3, that is responsible for growth hormone excess, and a gene, DNMT3A, in which mutations cause an overgrowth syndrome through epigenetic mechanisms. SUMMARY These recent advances in our understanding of somatic growth not only provide insight into childhood growth disorders but also have broader medical applications because disruption of these regulatory systems contributes to oncogenesis.
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Kamran F, Andrade AC, Nella AA, Clokie SJ, Rezvani G, Nilsson O, Baron J, Lui JC. Evidence That Up-Regulation of MicroRNA-29 Contributes to Postnatal Body Growth Deceleration. Mol Endocrinol 2015; 29:921-32. [PMID: 25866874 DOI: 10.1210/me.2015-1047] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Body growth is rapid in infancy but subsequently slows and eventually ceases due to a progressive decline in cell proliferation that occurs simultaneously in multiple organs. We previously showed that this decline in proliferation is driven in part by postnatal down-regulation of a large set of growth-promoting genes in multiple organs. We hypothesized that this growth-limiting genetic program is orchestrated by microRNAs (miRNAs). Bioinformatic analysis identified target sequences of the miR-29 family of miRNAs to be overrepresented in age-down-regulated genes. Concomitantly, expression microarray analysis in mouse kidney and lung showed that all members of the miR-29 family, miR-29a, -b, and -c, were strongly up-regulated from 1 to 6 weeks of age. Real-time PCR confirmed that miR-29a, -b, and -c were up-regulated with age in liver, kidney, lung, and heart, and their expression levels were higher in hepatocytes isolated from 5-week-old mice than in hepatocytes from embryonic mouse liver at embryonic day 16.5. We next focused on 3 predicted miR-29 target genes (Igf1, Imp1, and Mest), all of which are growth-promoting. A 3'-untranslated region containing the predicted target sequences from each gene was placed individually in a luciferase reporter construct. Transfection of miR-29 mimics suppressed luciferase gene activity for all 3 genes, and this suppression was diminished by mutating the target sequences, suggesting that these genes are indeed regulated by miR-29. Taken together, the findings suggest that up-regulation of miR-29 during juvenile life drives the down-regulation of multiple growth-promoting genes, thus contributing to physiological slowing and eventual cessation of body growth.
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Krupiński M, Urbańczyk-Zawadzka M, Laskowicz B, Irzyk M, Banyś R, Gruszczyńska K, Baron J. Computed tomography in the evaluation of the anomalous origin of the coronary artery: coexistence with other congenital heart disease in an adult population. Folia Morphol (Warsz) 2015; 74:73-7. [DOI: 10.5603/fm.2015.0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 07/22/2014] [Accepted: 07/23/2014] [Indexed: 11/25/2022]
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Lui JC, Chau M, Chen W, Cheung CSF, Hanson J, Rodriguez-Canales J, Nilsson O, Baron J. Spatial regulation of gene expression during growth of articular cartilage in juvenile mice. Pediatr Res 2015; 77:406-15. [PMID: 25521919 PMCID: PMC6354579 DOI: 10.1038/pr.2014.208] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 09/30/2014] [Indexed: 11/09/2022]
Abstract
BACKGROUND In juvenile mammals, the epiphyses of long bones grow by chondrogenesis within the articular cartilage. A better understanding of the molecular mechanisms that regulate the growth of articular cartilage may give insight into the antecedents of joint disease, such as osteoarthritis. METHODS We used laser capture microdissection to isolate chondrocytes from the superficial, middle, and deep zones of growing tibial articular cartilage in the 1-wk-old mouse and then investigated expression patterns by microarray. To identify molecular markers for each zone of the growing articular cartilage, we found genes showing zone-specific expression and confirmed by real-time PCR and in situ hybridization. RESULTS Bioinformatic analyses implicated ephrin receptor signaling, Wnt signaling, and bone morphogenetic protein signaling in the spatial regulation of chondrocyte differentiation during growth. Molecular markers were identified for superficial (e.g., Cilp, Prg4), middle (Cxcl14, Tnn), and deep zones (Sfrp5, Frzb). Comparison between juvenile articular and growth plate cartilage revealed that the superficial-to-deep zone transition showed similarity with the hypertrophic-to-resting zone transition. CONCLUSION Laser capture microdissection combined with microarray analysis identified novel signaling pathways that are spatially regulated in growing mouse articular cartilage and revealed similarities between the molecular architecture of the growing articular cartilage and that of growth plate cartilage.
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Cheung CSF, Zhu Z, Lui JCK, Dimitrov D, Baron J. Human monoclonal antibody fragments targeting matrilin-3 in growth plate cartilage. Pharm Res 2015; 32:2439-49. [PMID: 25690340 DOI: 10.1007/s11095-015-1636-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 01/21/2015] [Indexed: 11/26/2022]
Abstract
PURPOSE Many genetic disorders, including chondrodysplasias, and acquired disorders impair growth plate function, resulting in short and sometimes malformed bones. There are multiple endocrine and paracrine factors that promote chondrogenesis at the growth plate, which could potentially be used to treat these disorders. Targeting these growth factors specifically to the growth plate might augment the therapeutic skeletal effect while diminishing undesirable effects on non-target tissues. METHODS Using yeast display technology, we selected single-chain variable antibody fragments that bound to human and mouse matrilin-3, an extracellular matrix protein specifically expressed in cartilage tissue. The ability of the selected antibody fragments to bind matrilin-3 and to bind cartilage tissue in vitro and in vivo was assessed by ELISA and immunohistochemistry. RESULTS We identified antibody fragments that bound matrilin-3 with high affinity and also bound with high tissue specificity to cartilage homogenates and to cartilage structures in mouse embryo sections. When injected intravenously in mice, the antibody fragments specifically homed to cartilage. CONCLUSIONS Yeast display successfully selected antibody fragments that are able to target cartilage tissue in vivo. Coupling these antibodies to chondrogenic endocrine and paracrine signaling molecules has the potential to open up new pharmacological approaches to treat childhood skeletal growth disorders.
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Wood AR, Esko T, Yang J, Vedantam S, Pers TH, Gustafsson S, Chu AY, Estrada K, Luan J, Kutalik Z, Amin N, Buchkovich ML, Croteau-Chonka DC, Day FR, Duan Y, Fall T, Fehrmann R, Ferreira T, Jackson AU, Karjalainen J, Lo KS, Locke AE, Mägi R, Mihailov E, Porcu E, Randall JC, Scherag A, Vinkhuyzen AAE, Westra HJ, Winkler TW, Workalemahu T, Zhao JH, Absher D, Albrecht E, Anderson D, Baron J, Beekman M, Demirkan A, Ehret GB, Feenstra B, Feitosa MF, Fischer K, Fraser RM, Goel A, Gong J, Justice AE, Kanoni S, Kleber ME, Kristiansson K, Lim U, Lotay V, Lui JC, Mangino M, Mateo Leach I, Medina-Gomez C, Nalls MA, Nyholt DR, Palmer CD, Pasko D, Pechlivanis S, Prokopenko I, Ried JS, Ripke S, Shungin D, Stancáková A, Strawbridge RJ, Sung YJ, Tanaka T, Teumer A, Trompet S, van der Laan SW, van Setten J, Van Vliet-Ostaptchouk JV, Wang Z, Yengo L, Zhang W, Afzal U, Arnlöv J, Arscott GM, Bandinelli S, Barrett A, Bellis C, Bennett AJ, Berne C, Blüher M, Bolton JL, Böttcher Y, Boyd HA, Bruinenberg M, Buckley BM, Buyske S, Caspersen IH, Chines PS, Clarke R, Claudi-Boehm S, Cooper M, Daw EW, De Jong PA, Deelen J, Delgado G, Denny JC, Dhonukshe-Rutten R, Dimitriou M, Doney ASF, Dörr M, Eklund N, Eury E, Folkersen L, Garcia ME, Geller F, Giedraitis V, Go AS, Grallert H, Grammer TB, Gräßler J, Grönberg H, de Groot LCPGM, Groves CJ, Haessler J, Hall P, Haller T, Hallmans G, Hannemann A, Hartman CA, Hassinen M, Hayward C, Heard-Costa NL, Helmer Q, Hemani G, Henders AK, Hillege HL, Hlatky MA, Hoffmann W, Hoffmann P, Holmen O, Houwing-Duistermaat JJ, Illig T, Isaacs A, James AL, Jeff J, Johansen B, Johansson Å, Jolley J, Juliusdottir T, Junttila J, Kho AN, Kinnunen L, Klopp N, Kocher T, Kratzer W, Lichtner P, Lind L, Lindström J, Lobbens S, Lorentzon M, Lu Y, Lyssenko V, Magnusson PKE, Mahajan A, Maillard M, McArdle WL, McKenzie CA, McLachlan S, McLaren PJ, Menni C, Merger S, Milani L, Moayyeri A, Monda KL, Morken MA, Müller G, Müller-Nurasyid M, Musk AW, Narisu N, Nauck M, Nolte IM, Nöthen MM, Oozageer L, Pilz S, Rayner NW, Renstrom F, Robertson NR, Rose LM, Roussel R, Sanna S, Scharnagl H, Scholtens S, Schumacher FR, Schunkert H, Scott RA, Sehmi J, Seufferlein T, Shi J, Silventoinen K, Smit JH, Smith AV, Smolonska J, Stanton AV, Stirrups K, Stott DJ, Stringham HM, Sundström J, Swertz MA, Syvänen AC, Tayo BO, Thorleifsson G, Tyrer JP, van Dijk S, van Schoor NM, van der Velde N, van Heemst D, van Oort FVA, Vermeulen SH, Verweij N, Vonk JM, Waite LL, Waldenberger M, Wennauer R, Wilkens LR, Willenborg C, Wilsgaard T, Wojczynski MK, Wong A, Wright AF, Zhang Q, Arveiler D, Bakker SJL, Beilby J, Bergman RN, Bergmann S, Biffar R, Blangero J, Boomsma DI, Bornstein SR, Bovet P, Brambilla P, Brown MJ, Campbell H, Caulfield MJ, Chakravarti A, Collins R, Collins FS, Crawford DC, Cupples LA, Danesh J, de Faire U, den Ruijter HM, Erbel R, Erdmann J, Eriksson JG, Farrall M, Ferrannini E, Ferrières J, Ford I, Forouhi NG, Forrester T, Gansevoort RT, Gejman PV, Gieger C, Golay A, Gottesman O, Gudnason V, Gyllensten U, Haas DW, Hall AS, Harris TB, Hattersley AT, Heath AC, Hengstenberg C, Hicks AA, Hindorff LA, Hingorani AD, Hofman A, Hovingh GK, Humphries SE, Hunt SC, Hypponen E, Jacobs KB, Jarvelin MR, Jousilahti P, Jula AM, Kaprio J, Kastelein JJP, Kayser M, Kee F, Keinanen-Kiukaanniemi SM, Kiemeney LA, Kooner JS, Kooperberg C, Koskinen S, Kovacs P, Kraja AT, Kumari M, Kuusisto J, Lakka TA, Langenberg C, Le Marchand L, Lehtimäki T, Lupoli S, Madden PAF, Männistö S, Manunta P, Marette A, Matise TC, McKnight B, Meitinger T, Moll FL, Montgomery GW, Morris AD, Morris AP, Murray JC, Nelis M, Ohlsson C, Oldehinkel AJ, Ong KK, Ouwehand WH, Pasterkamp G, Peters A, Pramstaller PP, Price JF, Qi L, Raitakari OT, Rankinen T, Rao DC, Rice TK, Ritchie M, Rudan I, Salomaa V, Samani NJ, Saramies J, Sarzynski MA, Schwarz PEH, Sebert S, Sever P, Shuldiner AR, Sinisalo J, Steinthorsdottir V, Stolk RP, Tardif JC, Tönjes A, Tremblay A, Tremoli E, Virtamo J, Vohl MC, Amouyel P, Asselbergs FW, Assimes TL, Bochud M, Boehm BO, Boerwinkle E, Bottinger EP, Bouchard C, Cauchi S, Chambers JC, Chanock SJ, Cooper RS, de Bakker PIW, Dedoussis G, Ferrucci L, Franks PW, Froguel P, Groop LC, Haiman CA, Hamsten A, Hayes MG, Hui J, Hunter DJ, Hveem K, Jukema JW, Kaplan RC, Kivimaki M, Kuh D, Laakso M, Liu Y, Martin NG, März W, Melbye M, Moebus S, Munroe PB, Njølstad I, Oostra BA, Palmer CNA, Pedersen NL, Perola M, Pérusse L, Peters U, Powell JE, Power C, Quertermous T, Rauramaa R, Reinmaa E, Ridker PM, Rivadeneira F, Rotter JI, Saaristo TE, Saleheen D, Schlessinger D, Slagboom PE, Snieder H, Spector TD, Strauch K, Stumvoll M, Tuomilehto J, Uusitupa M, van der Harst P, Völzke H, Walker M, Wareham NJ, Watkins H, Wichmann HE, Wilson JF, Zanen P, Deloukas P, Heid IM, Lindgren CM, Mohlke KL, Speliotes EK, Thorsteinsdottir U, Barroso I, Fox CS, North KE, Strachan DP, Beckmann JS, Berndt SI, Boehnke M, Borecki IB, McCarthy MI, Metspalu A, Stefansson K, Uitterlinden AG, van Duijn CM, Franke L, Willer CJ, Price AL, Lettre G, Loos RJF, Weedon MN, Ingelsson E, O'Connell JR, Abecasis GR, Chasman DI, Goddard ME, Visscher PM, Hirschhorn JN, Frayling TM. Defining the role of common variation in the genomic and biological architecture of adult human height. Nat Genet 2014; 46:1173-86. [PMID: 25282103 PMCID: PMC4250049 DOI: 10.1038/ng.3097] [Citation(s) in RCA: 1192] [Impact Index Per Article: 119.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 08/29/2014] [Indexed: 12/17/2022]
Abstract
Using genome-wide data from 253,288 individuals, we identified 697 variants at genome-wide significance that together explained one-fifth of the heritability for adult height. By testing different numbers of variants in independent studies, we show that the most strongly associated ∼2,000, ∼3,700 and ∼9,500 SNPs explained ∼21%, ∼24% and ∼29% of phenotypic variance. Furthermore, all common variants together captured 60% of heritability. The 697 variants clustered in 423 loci were enriched for genes, pathways and tissue types known to be involved in growth and together implicated genes and pathways not highlighted in earlier efforts, such as signaling by fibroblast growth factors, WNT/β-catenin and chondroitin sulfate-related genes. We identified several genes and pathways not previously connected with human skeletal growth, including mTOR, osteoglycin and binding of hyaluronic acid. Our results indicate a genetic architecture for human height that is characterized by a very large but finite number (thousands) of causal variants.
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White B, Baron J, Chang Y, Camargo C, Brown D. 21 Applying Lean Methodologies Reduces Emergency Department Laboratory Turnaround Times. Ann Emerg Med 2014. [DOI: 10.1016/j.annemergmed.2014.07.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lui JC, Nilsson O, Baron J. Recent research on the growth plate: Recent insights into the regulation of the growth plate. J Mol Endocrinol 2014; 53:T1-9. [PMID: 24740736 PMCID: PMC4133284 DOI: 10.1530/jme-14-0022] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
For most bones, elongation is driven primarily by chondrogenesis at the growth plates. This process results from chondrocyte proliferation, hypertrophy, and extracellular matrix secretion, and it is carefully orchestrated by complex networks of local paracrine factors and modulated by endocrine factors. We review here recent advances in the understanding of growth plate physiology. These advances include new approaches to study expression patterns of large numbers of genes in the growth plate, using microdissection followed by microarray. This approach has been combined with genome-wide association studies to provide insights into the regulation of the human growth plate. We also review recent studies elucidating the roles of bone morphogenetic proteins, fibroblast growth factors, C-type natriuretic peptide, and suppressor of cytokine signaling in the local regulation of growth plate chondrogenesis and longitudinal bone growth.
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Nilsson O, Guo MH, Dunbar N, Popovic J, Flynn D, Jacobsen C, Lui JC, Hirschhorn JN, Baron J, Dauber A. Short stature, accelerated bone maturation, and early growth cessation due to heterozygous aggrecan mutations. J Clin Endocrinol Metab 2014; 99:E1510-8. [PMID: 24762113 PMCID: PMC4121031 DOI: 10.1210/jc.2014-1332] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
CONTEXT Many children with idiopathic short stature have a delayed bone age. Idiopathic short stature with advanced bone age is far less common. OBJECTIVE The aim was to identify underlying genetic causes of short stature with advanced bone age. SETTING AND DESIGN We used whole-exome sequencing to study three families with autosomal-dominant short stature, advanced bone age, and premature growth cessation. RESULTS Affected individuals presented with short stature [adult heights -2.3 to -4.2 standard deviation scores (SDS)] with histories of early growth cessation or childhood short stature (height SDS -1.9 to -3.5 SDS), advancement of bone age, and normal endocrine evaluations. Whole-exome sequencing identified novel heterozygous variants in ACAN, which encodes aggrecan, a proteoglycan in the extracellular matrix of growth plate and other cartilaginous tissues. The variants were present in all affected, but in no unaffected, family members. In Family 1, a novel frameshift mutation in exon 3 (c.272delA) was identified, which is predicted to cause early truncation of the aggrecan protein. In Family 2, a base-pair substitution was found in a highly conserved location within a splice donor site (c.2026+1G>A), which is also likely to alter the amino acid sequence of a large portion of the protein. In Family 3, a missense variant (c.7064T>C) in exon 14 affects a highly conserved residue (L2355P) and is strongly predicted to perturb protein function. CONCLUSIONS Our study demonstrates that heterozygous mutations in ACAN can cause a mild skeletal dysplasia, which presents clinically as short stature with advanced bone age. The accelerating effect on skeletal maturation has not previously been noted in the few prior reports of human ACAN mutations. Our findings thus expand the spectrum of ACAN defects and provide a new molecular genetic etiology for the unusual child who presents with short stature and accelerated skeletal maturation.
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Nilsson O, Weise M, Landman EBM, Meyers JL, Barnes KM, Baron J. Evidence that estrogen hastens epiphyseal fusion and cessation of longitudinal bone growth by irreversibly depleting the number of resting zone progenitor cells in female rabbits. Endocrinology 2014; 155:2892-9. [PMID: 24708243 PMCID: PMC4098010 DOI: 10.1210/en.2013-2175] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
With age, growth plate cartilage undergoes programmed senescence, eventually causing cessation of bone elongation and epiphyseal fusion. Estrogen accelerates this developmental process. We hypothesized that senescence occurs because progenitor cells in the resting zone are depleted in number and that estrogen acts by accelerating this depletion. To test this hypothesis, juvenile ovariectomized rabbits received injections of estradiol cypionate or vehicle for 5 weeks, and then were left untreated for an additional 5 weeks. Exposure to estrogen accelerated the normal decline in growth plate height and in the number of proliferative and hypertrophic chondrocytes. Five weeks after discontinuation of estrogen treatment, these structural parameters remained advanced, indicating an irreversible advancement in structural senescence. Similarly, transient estrogen exposure hastened epiphyseal fusion. Estrogen also caused a more rapid decline in functional parameters of growth plate senescence, including growth rate, proliferation rate, and hypertrophic cell size. However, in contrast to the structural parameters, once the estrogen treatment was discontinued, the growth rate, chondrocyte proliferation rate, and hypertrophic cell size all normalized, suggesting that estrogen has a reversible, suppressive effect on growth plate function. In addition, estrogen accelerated the normal loss of resting zone chondrocytes with age. This decrease in resting zone cell number did not appear to be due to apoptosis. However, it was maintained after the estrogen treatment stopped, suggesting that it represents irreversible depletion. The findings are consistent with the hypothesis that estrogen causes irreversible depletion of progenitor cells in the resting zone, thus irreversibly accelerating structural senescence and hastening epiphyseal fusion. In addition, estrogen reversibly suppresses growth plate function.
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Baron J, Fishbourne E, Couacy-Hyman E, Abubakar M, Jones BA, Frost L, Herbert R, Chibssa TR, Van't Klooster G, Afzal M, Ayebazibwe C, Toye P, Bashiruddin J, Baron MD. Development and testing of a field diagnostic assay for peste des petits ruminants virus. Transbound Emerg Dis 2014; 61:390-6. [PMID: 25073647 PMCID: PMC4283758 DOI: 10.1111/tbed.12266] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Indexed: 11/30/2022]
Abstract
We have developed an immunochromatographic test for the diagnosis of peste des petits ruminants (PPR) under field conditions. The diagnostic assay has been tested in the laboratory and also under field conditions in Ivory Coast, Pakistan, Ethiopia and Uganda. The test is carried out on a superficial swab sample (ocular or nasal) and showed a sensitivity of 84% relative to PCR. The specificity was 95% over all nasal and ocular samples. The test detected as little as 103 TCID50 (50% tissue culture infectious doses) of cell culture-grown virus, and detected virus isolates representing all four known genetic lineages of peste des petits ruminants virus. Virus could be detected in swabs from animals as early as 4 days post-infection, at a time when clinical signs were minimal. Feedback from field trials was uniformly positive, suggesting that this diagnostic tool may be useful for current efforts to control the spread of PPR.
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Chau M, Lui JC, Landman EBM, Späth SS, Vortkamp A, Baron J, Nilsson O. Gene expression profiling reveals similarities between the spatial architectures of postnatal articular and growth plate cartilage. PLoS One 2014; 9:e103061. [PMID: 25068449 PMCID: PMC4113381 DOI: 10.1371/journal.pone.0103061] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 06/26/2014] [Indexed: 11/18/2022] Open
Abstract
Articular and growth plate cartilage are discrete tissues but arise from a common cartilaginous condensation and have comparable spatial architectures consisting of distinct layers of chondrocytes. To investigate similarities and differences between articular and growth plate cartilage and to explore transcriptional changes that occur during the onset of their divergence, we performed manual microdissection of 10-day-old rat proximal tibias, microarray analysis, bioinformatics, and real-time PCR to compare gene expression profiles in individual cartilage layers. We found that many genes that were spatially upregulated in the intermediate/deep zone of articular cartilage were also spatially upregulated in the resting zone of growth plate cartilage (overlap greater than expected by chance, P<0.001). Interestingly, the superficial zone of articular cartilage showed an expression profile with similarities to both the proliferative and hypertrophic zones of growth plate cartilage (P<0.001 each). Additionally, significant numbers of known proliferative zone markers (3 out of 6) and hypertrophic zone markers (27 out of 126) were spatially upregulated in the superficial zone (more than expected by chance, P<0.001 each). In conclusion, we provide evidence that the intermediate/deep zone of articular cartilage has a gene expression profile more similar to that of the resting zone of growth plate cartilage, whereas the superficial zone has a gene expression profile more similar to those of the proliferative and hypertrophic zones. These findings suggest that the superficial zone chondrocytes of articular cartilage differentiate according to a program that is not completely different from but instead has distinct similarities to the hypertrophic differentiation program of growth plate chondrocytes. We also present functional signaling pathways implicated by differential gene expression between articular and growth plate cartilage during their initial separation by the secondary ossification center.
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Böttcher P, Buchkremer-Hermanns H, Baron J. Die Kristallstruktur des Ethylendiammonium-hexasulfids (2. Mitteilung über Alkylammonium-Polysulfide [1])/The Crystal Structure of Ethylenediammonium Hexasulfide. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-1984-0402] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Ethylenediammonium hexasulfide has been synthesized from ethylenediamine, sulfur, and gaseous H2S in aqueous solution. X-ray investigations on single crystals revealed its structure. The monoclinic unit cell contains eight formula units, the space group is Cc. The sulfur atoms form unbranched zig-zag chains S6
2- in all-trans-conformation.
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Delaney A, Padmanabhan V, Rezvani G, Chen W, Forcinito P, Cheung CS, Baron J, Lui JC. Evolutionary conservation and modulation of a juvenile growth-regulating genetic program. J Mol Endocrinol 2014; 52:269-77. [PMID: 24776848 PMCID: PMC4051439 DOI: 10.1530/jme-13-0263] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Body size varies enormously among mammalian species. In small mammals, body growth is typically suppressed rapidly, within weeks, whereas in large mammals, growth is suppressed slowly, over years, allowing for a greater adult size. We recently reported evidence that body growth suppression in rodents is caused in part by a juvenile genetic program that occurs in multiple tissues simultaneously and involves the downregulation of a large set of growth-promoting genes. We hypothesized that this genetic program is conserved in large mammals but that its time course is evolutionarily modulated such that it plays out more slowly, allowing for more prolonged growth. Consistent with this hypothesis, using expression microarray analysis, we identified a set of genes that are downregulated with age in both juvenile sheep kidney and lung. This overlapping gene set was enriched for genes involved in cell proliferation and growth and showed striking similarity to a set of genes downregulated with age in multiple organs of the juvenile mouse and rat, indicating that the multiorgan juvenile genetic program previously described in rodents has been conserved in the 80 million years since sheep and rodents diverged in evolution. Using microarray and real-time PCR, we found that the pace of this program was most rapid in mice, more gradual in rats, and most gradual in sheep. These findings support the hypothesis that a growth-regulating genetic program is conserved among mammalian species but that its pace is modulated to allow more prolonged growth and therefore greater adult body size in larger mammals.
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Giamanco NM, Jee YH, Shriver CD, Summers TA, Wellstein A, Baron J. Midkine and pleiotrophin concentrations in biopsy needle washout of breast masses. J Clin Oncol 2014. [DOI: 10.1200/jco.2014.32.15_suppl.e22104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Lui JC, Chen W, Cheung CSF, Baron J. Broad shifts in gene expression during early postnatal life are associated with shifts in histone methylation patterns. PLoS One 2014; 9:e86957. [PMID: 24489814 PMCID: PMC3904965 DOI: 10.1371/journal.pone.0086957] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 12/19/2013] [Indexed: 01/08/2023] Open
Abstract
During early postnatal life, extensive changes in gene expression occur concomitantly in multiple major organs, indicating the existence of a common core developmental genetic program. This program includes hundreds of growth-promoting genes that are downregulated with age in liver, kidney, lung, and heart, and there is evidence that this component of the program drives the widespread decline in cell proliferation that occurs in juvenile life, as organs approach adult sizes. To investigate epigenetic changes that might orchestrate this program, we performed chromatin immunoprecipitation-promoter tiling array to assess temporal changes in histone H3K4 and H3K27 trimethylation (me3) at promoter regions throughout the genome in kidney and lung, comparing 1- to 4-wk-old mice. We found extensive genome-wide shifts in H3K4me3 and H3K27me3 occurring with age in both kidney and lung. The number of genes with concordant changes in the two organs was far greater than expected by chance. Temporal changes in H3K4me3 showed a strong, positive association with changes in gene expression, assessed by microarray, whereas changes in H3K27me3 showed a negative association. Gene ontology analysis indicated that shifts in specific histone methylation marks were associated with specific developmental functions. Of particular interest, genes with decreases in H3K4me3 with age in both organs were strongly implicated in cell cycle and cell proliferation functions. Taken together, the findings suggest that the common core developmental program of gene expression which occurs in multiple organs during juvenile life is associated with a common core developmental program of histone methylation. In particular, declining H3K4me3 is strongly associated with gene downregulation and occurs in the promoter regions of many growth-regulating genes, suggesting that this change in histone methylation may contribute to the component of the genetic program that drives juvenile body growth deceleration.
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Wit JM, van Duyvenvoorde HA, van Klinken JB, Caliebe J, Bosch CA, Lui JC, Gijsbers AC, Bakker E, Breuning MH, Oostdijk W, Losekoot M, Baron J, Binder G, Ranke MB, Ruivenkamp CA. Copy number variants in short children born small for gestational age. Horm Res Paediatr 2014; 82:310-8. [PMID: 25300501 PMCID: PMC4236248 DOI: 10.1159/000367712] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/18/2014] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND/AIMS In addition to genome-wide association studies (GWAS), height-associated genes may be uncovered by studying individuals with extreme short or tall stature. METHODS Genome-wide analysis for copy number variants (CNVs), using single nucleotide polymorphism (SNP) arrays, was performed in 49 index cases born small for gestational age with persistent short stature. Segregation analysis was performed, and genes in CNVs were compared with information from GWAS, gene expression in rodents' growth plates, and published information. RESULTS CNVs were detected in 13 cases. In 5 children a known cause of short stature was found: UPD7, UPD14, a duplication of the SHOX enhancer region, an IGF1R deletion, and a 22q11.21 deletion. In the remaining 8 cases, potential pathogenic CNVs were detected, either de novo (n = 1), segregating (n = 2), or not segregating with short stature (n = 5). Bioinformatic analysis of the de novo and segregating CNVs suggested that HOXD4, AGPS, PDE11A, OSBPL6, PRKRA and PLEKHA3, and possibly DGKB and TNFRSF11B are potential candidate genes. A SERPINA7 or NRK defect may be associated with an X-linked form of short stature. CONCLUSION SNP arrays detected 5 known causes of short stature with prenatal onset and suggested several potential candidate genes.
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Jee YH, Baron J, Phillip M, Bhutta ZA. Malnutrition and catch-up growth during childhood and puberty. World Rev Nutr Diet 2014; 109:89-100. [PMID: 24457569 PMCID: PMC4803287 DOI: 10.1159/000356109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Baron J, Campbell WC, DeMille D, Doyle JM, Gabrielse G, Gurevich YV, Hess PW, Hutzler NR, Kirilov E, Kozyryev I, O'Leary BR, Panda CD, Parsons MF, Petrik ES, Spaun B, Vutha AC, West AD. Order of Magnitude Smaller Limit on the Electric Dipole Moment of the Electron. Science 2013; 343:269-72. [DOI: 10.1126/science.1248213] [Citation(s) in RCA: 749] [Impact Index Per Article: 68.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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89
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Cheung CS, Lui JC, Baron J. Identification of chondrocyte-binding peptides by phage display. J Orthop Res 2013; 31:1053-8. [PMID: 23440926 PMCID: PMC4803314 DOI: 10.1002/jor.22325] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 01/23/2013] [Indexed: 02/04/2023]
Abstract
As an initial step toward targeting cartilage tissue for potential therapeutic applications, we sought cartilage-binding peptides using phage display, a powerful technology for selection of peptides that bind to molecules of interest. A library of phage displaying random 12-amino acid peptides was iteratively incubated with cultured chondrocytes to select phage that bind cartilage. The resulting phage clones demonstrated increased affinity to chondrocytes by ELISA, when compared to a wild-type, insertless phage. Furthermore, the selected phage showed little preferential binding to other cell types, including primary skin fibroblast, myocyte and hepatocyte cultures, suggesting a tissue-specific interaction. Immunohistochemical staining revealed that the selected phage bound chondrocytes themselves and the surrounding extracellular matrix. FITC-tagged peptides were synthesized based on the sequence of cartilage-binding phage clones. These peptides, but not a random peptide, bound cultured chondrocytes, and extracelluar matrix. In conclusion, using phage display, we identified peptide sequences that specifically target chondrocytes. We anticipate that such peptides may be coupled to therapeutic molecules to provide targeted treatment for cartilage disorders.
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Sheppard C, Edmund J, Frawley K, Dubey G, Baron J, Burn S, Azeem T, Bhandari M, Chitkara K, Tukan A, McCance A, Kelly DJ. 128 MORE DISCHARGES, LESS FOLLOW-UP AND SIMILAR RATES OF CORONARY ANGIOGRAPHY: INITIAL ‘REAL-WORLD’ EXPERIENCE OF NICE GUIDANCE ON ASSESSMENT OF CHEST PAIN OF RECENT ONSET IN THE RAPID ACCESS CHEST PAIN CLINIC. Heart 2013. [DOI: 10.1136/heartjnl-2013-304019.128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Finkielstain GP, Lui JC, Baron J. Catch-up growth: cellular and molecular mechanisms. World Rev Nutr Diet 2013; 106:100-4. [PMID: 23428687 DOI: 10.1159/000342535] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In mammals, after a period of growth inhibition, body growth often does not just return to a normal rate but actually exceeds the normal rate, resulting in catch-up growth. Recent evidence suggests that catch-up growth occurs because growth-inhibiting conditions delay progression of the physiological mechanisms that normally cause body growth to slow and cease with age. As a result, following the period of growth inhibition, tissues retain a greater proliferative capacity than normal, and therefore grow more rapidly than normal for age. There is evidence that this mechanism contributes both to catch-up growth in terms of body length, which involves proliferation in the growth plate, and to catch-up growth in terms of organ mass, which involves proliferation in multiple nonskeletal tissues.
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Dauber A, Lafranchi SH, Maliga Z, Lui JC, Moon JE, McDeed C, Henke K, Zonana J, Kingman GA, Pers TH, Baron J, Rosenfeld RG, Hirschhorn JN, Harris MP, Hwa V. Novel microcephalic primordial dwarfism disorder associated with variants in the centrosomal protein ninein. J Clin Endocrinol Metab 2012; 97:E2140-51. [PMID: 22933543 PMCID: PMC3485598 DOI: 10.1210/jc.2012-2150] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
CONTEXT Microcephalic primordial dwarfism (MPD) is a rare, severe form of human growth failure in which growth restriction is evident in utero and continues into postnatal life. Single causative gene defects have been identified in a number of patients with MPD, and all involve genes fundamental to cellular processes including centrosome functions. OBJECTIVE The objective of the study was to find the genetic etiology of a novel presentation of MPD. DESIGN The design of the study was whole-exome sequencing performed on two affected sisters in a single family. Molecular and functional studies of a candidate gene were performed using patient-derived primary fibroblasts and a zebrafish morpholino oligonucleotides knockdown model. PATIENTS Two sisters presented with a novel subtype of MPD, including severe intellectual disabilities. MAIN OUTCOME MEASURES NIN, encoding Ninein, a centrosomal protein critically involved in asymmetric cell division, was identified as a candidate gene, and functional impacts in fibroblasts and zebrafish were studied. RESULTS From 34,606 genomic variants, two very rare missense variants in NIN were identified. Both probands were compound heterozygotes. In the zebrafish, ninein knockdown led to specific and novel defects in the specification and morphogenesis of the anterior neuroectoderm, resulting in a deformity of the developing cranium with a small, squared skull highly reminiscent of the human phenotype. CONCLUSION We identified a novel clinical subtype of MPD in two sisters who have rare variants in NIN. We show, for the first time, that reduction of ninein function in the developing zebrafish leads to specific deficiencies of brain and skull development, offering a developmental basis for the myriad phenotypes in our patients.
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Lui JC, Nilsson O, Chan Y, Palmer CD, Andrade AC, Hirschhorn JN, Baron J. Synthesizing genome-wide association studies and expression microarray reveals novel genes that act in the human growth plate to modulate height. Hum Mol Genet 2012; 21:5193-201. [PMID: 22914739 DOI: 10.1093/hmg/dds347] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Previous meta-analysis of genome-wide association (GWA) studies has identified 180 loci that influence adult height. However, each GWA locus typically comprises a set of contiguous genes, only one of which presumably modulates height. We reasoned that many of the causative genes within these loci influence height because they are expressed in and function in the growth plate, a cartilaginous structure that causes bone elongation and thus determines stature. Therefore, we used expression microarray studies of mouse and rat growth plate, human disease databases and a mouse knockout phenotype database to identify genes within the GWAS loci that are likely required for normal growth plate function. Each of these approaches identified significantly more genes within the GWA height loci than at random genomic locations (P < 0.0001 each), supporting the validity of the approach. The combined analysis strongly implicates 78 genes in growth plate function, including multiple genes that participate in PTHrP-IHH, BMP and CNP signaling, and many genes that have not previously been implicated in the growth plate. Thus, this analysis reveals a large number of novel genes that regulate human growth plate chondrogenesis and thereby contribute to the normal variations in human adult height. The analytic approach developed for this study may be applied to GWA studies for other common polygenic traits and diseases, thus providing a new general strategy to identify causative genes within GWA loci and to translate genetic associations into mechanistic biological insights.
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Kaleff C, Aschidamini C, Baron J, Di Leone C, Canavarro S, Vargas C. CorrectionBraz J Med Biol Res 2011; 44(8): 754-761Semi-automatic measurement of visual verticality perception in humans reveals a new category of visual field dependency. Braz J Med Biol Res 2011. [DOI: 10.1590/s0100-879x2011001000013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Chau M, Forcinito P, Andrade AC, Hegde A, Ahn S, Lui JC, Baron J, Nilsson O. Organization of the Indian hedgehog--parathyroid hormone-related protein system in the postnatal growth plate. J Mol Endocrinol 2011; 47:99-107. [PMID: 21642420 PMCID: PMC8287619 DOI: 10.1530/jme-10-0177] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In embryonic growth cartilage, Indian hedgehog (Ihh) and parathyroid hormone-related protein (PTHrP) participate in a negative feedback loop that regulates chondrocyte differentiation. Postnatally, this region undergoes major structural and functional changes. To explore the organization of the Ihh–PTHrP system in postnatal growth plate, we microdissected growth plates of 7-day-old rats into their constituent zones and assessed expression of genes participating in the h–PTHrP feedback loop. Ihh, Patched 1, Smoothened, Gli1, Gli2, Gli3, and Pthr1 were expressed in regions analogous to the expression domains in embryonic growth cartilage. However, PTHrP was expressed in resting zone cartilage, a site that differs from the embryonic source, the periarticular cells. We then used mice in which lacZ has replaced coding sequences of Gli1 and thus serves as a marker for active hedgehog signaling. At 1, 4, 8, and 12 weeks of age, lacZ expression was detected in a pattern analogous to that of embryonic cartilage. The findings support the hypothesis that the embryonic Ihh–PTHrP feedback loop is maintained in the postnatal growth plate except that the source of PTHrP has shifted to a more proximal location in the resting zone.
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Kaleff CR, Aschidamini C, Baron J, Di Leone CN, Leone CN, Canavarro S, Vargas CD. Semi-automatic measurement of visual verticality perception in humans reveals a new category of visual field dependency. Braz J Med Biol Res 2011; 44:754-61. [PMID: 21779636 DOI: 10.1590/s0100-879x2011007500090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Accepted: 04/04/2011] [Indexed: 11/21/2022] Open
Abstract
Previous assessment of verticality by means of rod and rod and frame tests indicated that human subjects can be more (field dependent) or less (field independent) influenced by a frame placed around a tilted rod. In the present study we propose a new approach to these tests. The judgment of visual verticality (rod test) was evaluated in 50 young subjects (28 males, ranging in age from 20 to 27 years) by randomly projecting a luminous rod tilted between -18 and +18° (negative values indicating left tilts) onto a tangent screen. In the rod and frame test the rod was displayed within a luminous fixed frame tilted at +18 or -18°. Subjects were instructed to verbally indicate the rod's inclination direction (forced choice). Visual dependency was estimated by means of a Visual Index calculated from rod and rod and frame test values. Based on this index, volunteers were classified as field dependent, intermediate and field independent. A fourth category was created within the field-independent subjects for whom the amount of correct guesses in the rod and frame test exceeded that of the rod test, thus indicating improved performance when a surrounding frame was present. In conclusion, the combined use of subjective visual vertical and the rod and frame test provides a specific and reliable form of evaluation of verticality in healthy subjects and might be of use to probe changes in brain function after central or peripheral lesions.
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Abstract
Recent studies have begun to provide insight into a long-standing mystery in biology-why body growth in animals is rapid in early life but then progressively slows, thus imposing a limit on adult body size. This growth deceleration in mammals is caused by potent suppression of cell proliferation in multiple tissues and is driven primarily by local, rather than systemic, mechanisms. Recent evidence suggests that this progressive decline in proliferation results from a genetic program that occurs in multiple organs and involves the down-regulation of a large set of growth-promoting genes. This program does not appear to be driven simply by time, but rather depends on growth itself, suggesting that the limit on adult body size is imposed by a negative feedback loop. Different organs appear to use different types of information to precisely target their adult size. For example, skeletal and cardiac muscle growth are negatively regulated by myostatin, the concentration of which depends on muscle mass itself. Liver growth appears to be modulated by bile acid flux, a parameter that reflects organ function. In pancreas, organ size appears to be limited by the initial number of progenitor cells, suggesting a mechanism based on cell-cycle counting. Further elucidation of the fundamental mechanisms suppressing juvenile growth is likely to yield important insights into the pathophysiology of childhood growth disorders and of the unrestrained growth of cancer. In addition, improved understanding of these growth-suppressing mechanisms may someday allow their therapeutic suspension in adult tissues to facilitate tissue regeneration.
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Ott H, Tenbrock K, Baron J, Merk H, Lehmann S. Basophil Activation Test for the Diagnosis of Hymenoptera Venom Allergy in Childhood: a Pilot Study. KLINISCHE PADIATRIE 2011; 223:27-32. [DOI: 10.1055/s-0030-1268430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Lui JC, Nilsson O, Baron J. Growth plate senescence and catch-up growth. ENDOCRINE DEVELOPMENT 2011; 21:23-29. [PMID: 21865751 PMCID: PMC3420820 DOI: 10.1159/000328117] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Longitudinal bone growth is rapid in prenatal and early postnatal life, but then slows with age and eventually ceases. This growth deceleration is caused primarily by a decrease in chondrocyte proliferation, and is associated with other structural, functional, and molecular changes collectively termed growth plate senescence. Current evidence suggests that growth plate senescence occurs because the progenitor chondrocytes in the resting zone have a limited replicative capacity which is gradually exhausted with increasing cell division. In addition, recent experimental findings from laboratory and clinical studies suggest that growth plate senescence explains the phenomenon of catch-up growth. Growth-inhibiting conditions such as glucocorticoid excess and hypothyroidism delay the program of growth plate senescence. Consequently, growth plates are less senescent after these conditions resolve and therefore grow more rapidly than is normal for age, resulting in catch-up growth.
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Forcinito P, Andrade AC, Finkielstain GP, Baron J, Nilsson O, Lui JC. Growth-inhibiting conditions slow growth plate senescence. J Endocrinol 2011; 208:59-67. [PMID: 20974641 PMCID: PMC6289067 DOI: 10.1677/joe-10-0302] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The mammalian growth plate undergoes programmed senescence during juvenile life, causing skeletal growth to slow with age. We previously found that hypothyroidism in rats slowed both growth plate chondrocyte proliferation and growth plate senescence, suggesting that senescence is not dependent on age per se but rather on chondrocyte proliferation. However, one alternative explanation is that the observed slowing of growth plate senescence is a specific consequence of hypothyroidism. We reasoned that, if delayed senescence is a general consequence of growth inhibition, rather than a specific result of hypothyroidism, then senescence would also be slowed by other growth-inhibiting conditions. In this study, we therefore used tryptophan deficiency to temporarily inhibit growth in newborn rats for 4 weeks. We then allowed the animals to recover and studied the effects on growth plate senescence. We found that structural, functional, and molecular markers of growth plate senescence were delayed by prior tryptophan deficiency, indicating that the developmental program of senescence had occurred more slowly during the period of growth inhibition. Taken together with previous studies in hypothyroid rats, our findings support the hypothesis that delayed senescence is a general consequence of growth inhibition and hence that growth plate senescence is not simply a function of time per se but rather depends on growth.
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