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1.
Thyroid ; 34(1): 10-13, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37885215
2.
Nat Aging ; 3(8): 931-937, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37400721

RESUMO

Cognitive dysfunction in aging is a major biomedical challenge. Whether treatment with klotho, a longevity factor, could enhance cognition in human-relevant models such as in nonhuman primates is unknown and represents a major knowledge gap in the path to therapeutics. We validated the rhesus form of the klotho protein in mice showing it increased synaptic plasticity and cognition. We then found that a single administration of low-dose, but not high-dose, klotho enhanced memory in aged nonhuman primates. Systemic low-dose klotho treatment may prove therapeutic in aging humans.


Assuntos
Glucuronidase , Longevidade , Camundongos , Humanos , Animais , Idoso , Glucuronidase/metabolismo , Envelhecimento , Cognição , Primatas/metabolismo
3.
JBMR Plus ; 7(6): e10739, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37283649

RESUMO

The nuclear factor I/X (NFIX) gene encodes a ubiquitously expressed transcription factor whose mutations lead to two allelic disorders characterized by developmental, skeletal, and neural abnormalities, namely, Malan syndrome (MAL) and Marshall-Smith syndrome (MSS). NFIX mutations associated with MAL mainly cluster in exon 2 and are cleared by nonsense-mediated decay (NMD) leading to NFIX haploinsufficiency, whereas NFIX mutations associated with MSS are clustered in exons 6-10 and escape NMD and result in the production of dominant-negative mutant NFIX proteins. Thus, different NFIX mutations have distinct consequences on NFIX expression. To elucidate the in vivo effects of MSS-associated NFIX exon 7 mutations, we used CRISPR-Cas9 to generate mouse models with exon 7 deletions that comprised: a frameshift deletion of two nucleotides (Nfix Del2); in-frame deletion of 24 nucleotides (Nfix Del24); and deletion of 140 nucleotides (Nfix Del140). Nfix +/Del2, Nfix +/Del24, Nfix +/Del140, Nfix Del24/Del24, and Nfix Del140/Del140 mice were viable, normal, and fertile, with no skeletal abnormalities, but Nfix Del2/Del2 mice had significantly reduced viability (p < 0.002) and died at 2-3 weeks of age. Nfix Del2 was not cleared by NMD, and NfixDel2/Del2 mice, when compared to Nfix +/+ and Nfix +/Del2 mice, had: growth retardation; short stature with kyphosis; reduced skull length; marked porosity of the vertebrae with decreased vertebral and femoral bone mineral content; and reduced caudal vertebrae height and femur length. Plasma biochemistry analysis revealed Nfix Del2/Del2 mice to have increased total alkaline phosphatase activity but decreased C-terminal telopeptide and procollagen-type-1-N-terminal propeptide concentrations compared to Nfix +/+ and Nfix +/Del2 mice. Nfix Del2/Del2 mice were also found to have enlarged cerebral cortices and ventricular areas but smaller dentate gyrus compared to Nfix +/+ mice. Thus, Nfix Del2/Del2 mice provide a model for studying the in vivo effects of NFIX mutants that escape NMD and result in developmental abnormalities of the skeletal and neural tissues that are associated with MSS. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

4.
JCI Insight ; 8(12)2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37345656

RESUMO

Hypochondroplasia (HCH) is a mild dwarfism caused by missense mutations in fibroblast growth factor receptor 3 (FGFR3), with the majority of cases resulting from a heterozygous p.Asn540Lys gain-of-function mutation. Here, we report the generation and characterization of the first mouse model (Fgfr3Asn534Lys/+) of HCH to our knowledge. Fgfr3Asn534Lys/+ mice exhibited progressive dwarfism and impairment of the synchondroses of the cranial base, resulting in defective formation of the foramen magnum. The appendicular and axial skeletons were both severely affected and we demonstrated an important role of FGFR3 in regulation of cortical and trabecular bone structure. Trabecular bone mineral density (BMD) of long bones and vertebral bodies was decreased, but cortical BMD increased with age in both tibiae and femurs. These results demonstrate that bones in Fgfr3Asn534Lys/+ mice, due to FGFR3 activation, exhibit some characteristics of osteoporosis. The present findings emphasize the detrimental effect of gain-of-function mutations in the Fgfr3 gene on long bone modeling during both developmental and aging processes, with potential implications for the management of elderly patients with hypochondroplasia and osteoporosis.


Assuntos
Nanismo , Osteoporose , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos , Animais , Camundongos , Calcificação Fisiológica , Nanismo/genética , Mutação com Ganho de Função , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética
5.
Psychopharmacology (Berl) ; 240(5): 1033-1048, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36961560

RESUMO

RATIONALE: Dopamine (DA) signaling through the D1 receptor has been shown to be integral to multiple aspects of cognition, including the core process of working memory. The discovery of positive allosteric modulators (PAMs) of the D1 receptor has enabled treatment modalities that may have alternative benefits to orthosteric D1 agonists arising from a synergism of action with functional D1 receptor signaling. OBJECTIVES: To investigate this potential, we have studied the effects of the novel D1 PAM DPTQ on a spatial delayed response working memory task in the rhesus monkey. Initial studies indicated that DPTQ binds to primate D1R with high affinity and selectivity and elevates spontaneous eye blink rate in rhesus monkeys in a dose-dependent manner consistent with plasma ligand exposures and central D1activation. RESULTS: Based on those results, DPTQ was tested at 2.5 mg/kg IM in the working memory task. No acute effect was observed 1 h after dosing, but performance was impaired 48 h later. Remarkably, this deficit was immediately followed by a significant enhancement in cognition over the next 3 days. In a second experiment in which DPTQ was administered on days 1 and 5, the early impairment was smaller and did not reach statistical significance, but statistically significant enhancement of performance was observed over the following week. Lower doses of 0.1 and 1.0 mg/kg were also capable of producing this protracted enhancement without inducing any transient impairment. CONCLUSIONS: DPTQ exemplifies a class of D1PAMs that may be capable of providing long-term improvements in working memory.


Assuntos
Memória de Curto Prazo , Receptores de Dopamina D1 , Animais , Receptores de Dopamina D1/metabolismo , Dopamina/metabolismo , Agonistas de Dopamina/farmacologia , Memória Espacial
6.
Simul Healthc ; 18(2): 82-89, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35238848

RESUMO

INTRODUCTION: Simulation tools to assess prehospital team performance and identify patient safety events are lacking. We adapted a simulation model and checklist tool of individual paramedic performance to assess prehospital team performance and tested interrater reliability. METHODS: We used a modified Delphi process to adapt 3 simulation cases (cardiopulmonary arrest, seizure, asthma) and checklist to add remote physician direction, target infants, and evaluate teams of 2 paramedics and 1 physician. Team performance was assessed with a checklist of steps scored as complete/incomplete by raters using direct observation or video review. The composite performance score was the percentage of completed steps. Interrater percent agreement was compared with the original tool. The tool was modified, and raters trained in iterative rounds until composite performance scoring agreement was 0.80 or greater (scale <0.20 = poor; 0.21-0.39 = fair, 0.40-0.59 = moderate; 0.60-0.79 = good; 0.80-1.00 = very good). RESULTS: We achieved very good interrater agreement for scoring composite performance in 2 rounds using 6 prehospital teams and 4 raters. The original 175 step tool was modified to 171 steps. Interrater percent agreement for the final modified tool approximated the original tool for the composite checklist (0.80 vs. 0.85), cardiopulmonary arrest (0.82 vs. 0.86), and asthma cases (0.80 vs. 0.77) but was lower for the seizure case (0.76 vs. 0.91). Most checklist items (137/171, 80%) had good-very good agreement. Among 34 items with fair-moderate agreement, 15 (44%) related to patient assessment, 9 (26%) equipment use, 6 (18%) medication delivery, and 4 (12%) cardiopulmonary resuscitation quality. CONCLUSIONS: The modified checklist has very good agreement for assessing composite prehospital team performance and can be used to test effects of patient safety interventions.


Assuntos
Serviços Médicos de Emergência , Parada Cardíaca , Lactente , Humanos , Criança , Lista de Checagem , Reprodutibilidade dos Testes , Parada Cardíaca/diagnóstico , Parada Cardíaca/terapia , Convulsões
7.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36499391

RESUMO

The SH-SY5Y neuroblastoma cells are a widely used in vitro model approximating neurons for testing the target engagement of therapeutics designed for neurodegenerative diseases and pain disorders. However, their potential as a model for receptor-mediated delivery and uptake of novel modalities, such as antibody-drug conjugates, remains understudied. Investigation of the SH-SY5Y cell surfaceome will aid in greater in vitro to in vivo correlation of delivery and uptake, thereby accelerating drug discovery. So far, the majority of studies have focused on total cell proteomics from undifferentiated and differentiated SH-SY5Y cells. While some studies have investigated the expression of specific proteins in neuroblastoma tissue, a global approach for comparison of neuroblastoma cell surfaceome to the brain and dorsal root ganglion (DRG) neurons remains uninvestigated. Furthermore, an isoform-specific evaluation of cell surface proteins expressed on neuroblastoma cells remains unexplored. In this study, we define a bioinformatic workflow for the identification of high-confidence surface proteins expressed on brain and DRG neurons using tissue proteomic and transcriptomic data. We then delineate the SH-SY5Y cell surfaceome by surface proteomics and show that it significantly overlaps with the human brain and DRG neuronal surface proteome. We find that, for 32% of common surface proteins, SH-SY5Y-specific major isoforms are alternatively spliced, maintaining their protein-coding ability, and are predicted to localize to the cell surface. Validation of these isoforms using surface proteomics confirms a SH-SY5Y-specific alternative NRCAM (neuron-glia related cell adhesion molecule) isoform, which is absent in typical brain neurons, but present in neuroblastomas, making it a receptor of interest for neuroblastoma-specific therapeutics.


Assuntos
Neuroblastoma , Humanos , Neuroblastoma/terapia , Neuroblastoma/tratamento farmacológico , Linhagem Celular Tumoral , Proteômica , Neurônios/metabolismo , Diferenciação Celular/fisiologia , Proteínas de Membrana/metabolismo
8.
Clin Endocrinol (Oxf) ; 97(5): 664-675, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35274331

RESUMO

OBJECTIVE: Thyroid status in the months following radioiodine (RI) treatment for Graves' disease can be unstable. Our objective was to quantify frequency of abnormal thyroid function post-RI and compare effectiveness of common management strategies. DESIGN: Retrospective, multicentre and observational study. PATIENTS: Adult patients with Graves' disease treated with RI with 12 months' follow-up. MEASUREMENTS: Euthyroidism was defined as both serum thyrotropin (thyroid-stimulating hormone [TSH]) and free thyroxine (FT4) within their reference ranges or, when only one was available, it was within its reference range; hypothyroidism as TSH ≥ 10 mU/L, or subnormal FT4 regardless of TSH; hyperthyroidism as TSH below and FT4 above their reference ranges; dysthyroidism as the sum of hypo- and hyperthyroidism; subclinical hypothyroidism as normal FT4 and TSH between the upper limit of normal and <10 mU/L; and subclinical hyperthyroidism as low TSH and normal FT4. RESULTS: Of 812 patients studied post-RI, hypothyroidism occurred in 80.7% and hyperthyroidism in 48.6% of patients. Three principal post-RI management strategies were employed: (a) antithyroid drugs alone, (b) levothyroxine alone, and (c) combination of the two. Differences among these were small. Adherence to national guidelines regarding monitoring thyroid function in the first 6 months was low (21.4%-28.7%). No negative outcomes (new-onset/exacerbation of Graves' orbitopathy, weight gain, and cardiovascular events) were associated with dysthyroidism. There were significant differences in demographics, clinical practice, and thyroid status postradioiodine between centres. CONCLUSIONS: Dysthyroidism in the 12 months post-RI was common. Differences between post-RI strategies were small, suggesting these interventions alone are unlikely to address the high frequency of dysthyroidism.


Assuntos
Doença de Graves , Oftalmopatia de Graves , Hipertireoidismo , Hipotireoidismo , Adulto , Antitireóideos/uso terapêutico , Doença de Graves/radioterapia , Humanos , Hipertireoidismo/radioterapia , Hipotireoidismo/tratamento farmacológico , Radioisótopos do Iodo/uso terapêutico , Estudos Retrospectivos , Tireotropina , Tiroxina/uso terapêutico
9.
J Sports Sci ; 40(10): 1078-1087, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35257642

RESUMO

The journey of young athletes on the talent pathway in sport has been identified as non-linear. Central to this has been the influence of challenging experiences, yet little is known on the experiences of currently young athletes during the challenge, particularly in the early years of the talent pathway. The purpose of this study was to explore the experiences of young athletes as they negotiated their self-identified most difficult challenge. Eight participants were purposefully sampled based on their involvement in the early years of a talent pathway and their status as currently young athletes. Individual semi-structured interviews were conducted at two time points separated by five months. Data was analysed via thematic analysis. Participants identified the bespoke nature and impact of their most difficult challenge, a range of psychobehavioural skills and diverse social support to engage with and embrace their most difficult challenge and the influence of their most difficult challenge on the preparation for future challenges. Talent pathway stakeholders should be cognisant of the preparation, individualisation and reflection processes required to optimise talent development via challenges. Specifically, young athletes should be supported in skilfully deploying psychobehavioural skills, assisted by key personnel who purposefully aid in navigating the most difficult challenges.


Assuntos
Aptidão , Esportes , Atletas , Humanos , Apoio Social
10.
PLoS One ; 17(1): e0262995, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35077515

RESUMO

Long-term athletic development practices have been recommended for the past two decades. However, limited research exists exploring the knowledge and skills required by practitioners to optimise long-term athletic development. Therefore, this study aimed to evaluate the knowledge, adherence, practices, and challenges of practitioners responsible for delivering long-term athletic development. A mixed methods survey was completed by 236 practitioners (e.g., sport coaches, physical education teachers) consisting of four parts; 1) demographics, 2) knowledge, 3) adherence, and 4) practices and challenges. Quantitative and qualitative data were analysed by Friedman's analysis of variance and thematic analyses, respectively. Quantitative findings showed practitioners 1) recognised their responsibility for delivering long-term athletic development, 2) have a familiarity with existing developmental models, and 3) had high adherence, focused upon health and wellbeing, to delivering long-term athletic development. However, practices associated with growth and maturity, monitoring and assessment, and the systematic progression and individualisation of training had lower adherence. Qualitative analysis indicated that practitioner's perceived definitions of athleticism and long-term athletic development were inconsistent, especially according to the psychological components (i.e., confidence). Practitioners' descriptions of their long-term athletic development practices identified two higher order themes; 1) goals, in which long-term athletic development "is for life" and the importance of "an individual centered journey" highlighted as sub-themes; and 2) realities of delivering long-term athletic development, whereby variety in programme delivery, monitoring development and practical challenges were noted as key priorities. Eight practical challenges were identified including governance and priorities, resources, education, early specialization, high training volumes, staff communication, parents and youth motivation. This mixed method survey highlighted a multitude of knowledge, adherence, practices and challenges towards long-term athletic development. These novel findings can help inform policy to optimise long-term athletic development and to support the complex problem of developing a healthier, fitter and more physically active youth population.


Assuntos
Atletas , Educação Física e Treinamento , Esportes , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Endocrinology ; 163(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34669927

RESUMO

Thyroid hormones (TH) are essential for skeletal development and adult bone homeostasis. Their bioavailability is determined by specific transporter proteins at the cell surface. The TH-specific transporter monocarboxylate transporter 8 (MCT8) was recently reported as a regulator of bone mass in mice. Given that high systemic triiodothyronine (T3) levels in Mct8 knockout (KO) mice are still able to cause trabecular bone loss, alternative TH transporters must substitute for MCT8 function in bone. In this study, we analyzed the skeletal phenotypes of male Oatp1c1 KO and Mct10 KO mice, which are euthyroid, and male Mct8/Oatp1c1 and Mct8/Mct10 double KO mice, which have elevated circulating T3 levels, to unravel the role of TH transport in bone. MicroCT analysis showed no significant trabecular bone changes in Oatp1c1 KO mice at 4 weeks and 16 weeks of age compared with wild-type littermate controls, whereas 16-week-old Mct8/Oatp1c1 double KO animals displayed trabecular bone loss. At 12 weeks, Mct10 KO mice, but not Mct8/Mct10 double KO mice, had decreased trabecular femoral bone volume with reduced osteoblast numbers. By contrast, lack of Mct10 in 24-week-old mice led to trabecular bone gain at the femur with increased osteoblast numbers and decreased osteoclast numbers whereas Mct8/Mct10 double KO did not alter bone mass. Neither Mct10 nor Mct8/Mct10 deletion affected vertebral bone structures at both ages. In vitro, osteoblast differentiation and activity were impaired by Mct10 and Mct8/Mct10-deficiency. These data demonstrate that MCT10, but not OATP1C1, is a site- and age-dependent regulator of bone mass and turnover in male mice.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Osso e Ossos/metabolismo , Animais , Transporte Biológico , Fenômenos Biomecânicos , Osso Esponjoso/metabolismo , Diferenciação Celular , Fêmur/fisiologia , Homeostase , Masculino , Camundongos , Camundongos Knockout , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteócitos/citologia , Fenótipo , Simportadores/metabolismo , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo , Tri-Iodotironina/metabolismo , Microtomografia por Raio-X
12.
Front Endocrinol (Lausanne) ; 12: 720728, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925226

RESUMO

A synoptic overview of scientific methods applied in bone and associated research fields across species has yet to be published. Experts from the EU Cost Action GEMSTONE ("GEnomics of MusculoSkeletal Traits translational Network") Working Group 2 present an overview of the routine techniques as well as clinical and research approaches employed to characterize bone phenotypes in humans and selected animal models (mice and zebrafish) of health and disease. The goal is consolidation of knowledge and a map for future research. This expert paper provides a comprehensive overview of state-of-the-art technologies to investigate bone properties in humans and animals - including their strengths and weaknesses. New research methodologies are outlined and future strategies are discussed to combine phenotypic with rapidly developing -omics data in order to advance musculoskeletal research and move towards "personalised medicine".


Assuntos
Osso e Ossos/metabolismo , Genômica/métodos , Fenômenos Fisiológicos Musculoesqueléticos/genética , Animais , Osso e Ossos/patologia , Redes Reguladoras de Genes/fisiologia , Humanos , Camundongos , Modelos Animais , Fenótipo , Proteômica/métodos , Peixe-Zebra
13.
Patterns (N Y) ; 2(12): 100366, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34909703

RESUMO

Coronavirus disease 2019 (COVID-19) has highlighted the need for the timely collection and sharing of public health data. It is important that data sharing is balanced with protecting confidentiality. Here we discuss an innovative mechanism to protect health data, called differential privacy. Differential privacy is a mathematically rigorous definition of privacy that aims to protect against all possible adversaries. In layperson's terms, statistical noise is applied to the data so that overall patterns can be described, but data on individuals are unlikely to be extracted. One of the first use cases for health data in Australia is the development of the COVID-19 Real-Time Information System for Preparedness and Epidemic Response (CRISPER), which provides proof of concept for the use of this technology in the health sector. If successful, this will benefit future sharing of public health data.

14.
Front Public Health ; 9: 753493, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858930

RESUMO

Accurate and current information has been highlighted across the globe as a critical requirement for the COVID-19 pandemic response. To address this need, many interactive dashboards providing a range of different information about COVID-19 have been developed. A similar tool in Australia containing current information about COVID-19 could assist general practitioners and public health responders in their pandemic response efforts. The COVID-19 Real-time Information System for Preparedness and Epidemic Response (CRISPER) has been developed to provide accurate and spatially explicit real-time information for COVID-19 cases, deaths, testing and contact tracing locations in Australia. Developed based on feedback from key users and stakeholders, the system comprises three main components: (1) a data engine; (2) data visualization and interactive mapping tools; and (3) an automated alert system. This system provides integrated data from multiple sources in one platform which optimizes information sharing with public health responders, primary health care practitioners and the general public.


Assuntos
COVID-19 , Pandemias , Austrália/epidemiologia , Humanos , Sistemas de Informação , SARS-CoV-2
15.
Front Endocrinol (Lausanne) ; 12: 709711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539568

RESUMO

Genetic disorders of the skeleton encompass a diverse group of bone diseases differing in clinical characteristics, severity, incidence and molecular etiology. Of particular interest are the monogenic rare bone mass disorders, with the underlying genetic defect contributing to either low or high bone mass phenotype. Extensive, deep phenotyping coupled with high-throughput, cost-effective genotyping is crucial in the characterization and diagnosis of affected individuals. Massive parallel sequencing efforts have been instrumental in the discovery of novel causal genes that merit functional validation using in vitro and ex vivo cell-based techniques, and in vivo models, mainly mice and zebrafish. These translational models also serve as an excellent platform for therapeutic discovery, bridging the gap between basic science research and the clinic. Altogether, genetic studies of monogenic rare bone mass disorders have broadened our knowledge on molecular signaling pathways coordinating bone development and metabolism, disease inheritance patterns, development of new and improved bone biomarkers, and identification of novel drug targets. In this comprehensive review we describe approaches to further enhance the innovative processes taking discoveries from clinic to bench, and then back to clinic in rare bone mass disorders. We highlight the importance of cross laboratory collaboration to perform functional validation in multiple model systems after identification of a novel disease gene. We describe the monogenic forms of rare low and high rare bone mass disorders known to date, provide a roadmap to unravel the genetic determinants of monogenic rare bone mass disorders using proper phenotyping and genotyping methods, and describe different genetic validation approaches paving the way for future treatments.


Assuntos
Densidade Óssea , Doenças Ósseas/genética , Doenças Ósseas/patologia , Genes , Mutação , Animais , Doenças Ósseas/terapia , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fenótipo
16.
Thyroid ; 31(11): 1707-1714, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34514857

RESUMO

Background: Survivors of pediatric differentiated thyroid carcinoma (DTC) receive thyrotropin-suppressive therapy to minimize disease recurrence. However, knowledge about long-term effects of subclinical hyperthyroidism on bone mineral density (BMD) in pediatric DTC survivors is scarce, as is the information regarding long-term consequences of permanent hypoparathyroidism on BMD. We evaluated BMD in pediatric DTC survivors and investigated if BMD was affected by subclinical hyperthyroidism and/or permanent hypoparathyroidism during long-term follow-up. Methods: In this nationwide longitudinal study, we determined BMD in the lumbar spine and femur by dual energy X-ray absorptiometry in 65 pediatric DTC survivors. Measurements were repeated after minimal 5 years of follow-up in 46 pediatric DTC survivors. BMD results were evaluated according to the recommendations of the International Society for Clinical Densitometry (ISCD) and WHO. At both visits, we determined biochemical parameters and markers of bone resorption (C-terminal telopeptide of type I collagen [ß-CTX]) and formation (N-propeptide of type I collagen [PINP] and osteocalcin). Results: First and second BMD measurements were done after a median follow-up of 17.0 (interquartile range [IQR] 8.0-25.0) and 23.5 (IQR 14.0-30.0) years after diagnosis, respectively. Median age at diagnosis was 15 years (IQR 13.0-17.0). Twenty-nine percent of the survivors had subclinical hyperthyroidism. In most survivors, BMD T- and Z-scores were within the reference range during both BMD evaluations. However, after 23.5 years of follow-up, a low BMD was found in 13.0%. In the 13 survivors with permanent hypoparathyroidism, BMD values did not differ after 5 years of follow-up compared with baseline values or in comparison with the 33 survivors without permanent hypoparathyroidism. During follow-up, turnover markers ß-CTX and PINP remained stable. Conclusions: This longitudinal study of pediatric DTC survivors demonstrated normal and stable median lumbar spine and femur BMD values after a median time of 17 and 23.5 years after diagnosis. However, compared with controls, a lower BMD was still found in 13.0% after prolonged follow-up despite intensive follow-up. Based on the studied follow-up period, these data do not provide convincing evidence in support of standard monitoring of bone mass among DTC survivors, but may be restricted to individual cases at low frequency. Trial Registration: This follow-up study was registered in The Netherlands Trial Register under no. NL3280 (www.trialregister.nl/trial/3280).


Assuntos
Densidade Óssea , Hipertireoidismo/etiologia , Neoplasias da Glândula Tireoide/complicações , Absorciometria de Fóton , Adolescente , Criança , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Países Baixos , Sobreviventes
17.
JBMR Plus ; 5(7): e10509, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34258505

RESUMO

Ras homologous guanosine triphosphatases (RhoGTPases) control several cellular functions, including cytoskeletal actin remodeling and cell migration. Their activities are downregulated by GTPase-activating proteins (GAPs). Although RhoGTPases are implicated in bone remodeling and osteoclast and osteoblast function, their significance in human bone health and disease remains elusive. Here, we report defective RhoGTPase regulation as a cause of severe, early-onset, autosomal-dominant skeletal fragility in a three-generation Finnish family. Affected individuals (n = 13) presented with multiple low-energy peripheral and vertebral fractures despite normal bone mineral density (BMD). Bone histomorphometry suggested reduced bone volume, low surface area covered by osteoblasts and osteoclasts, and low bone turnover. Exome sequencing identified a novel heterozygous missense variant c.652G>A (p.G218R) in ARHGAP25, encoding a GAP for Rho-family GTPase Rac1. Variants in the ARHGAP25 5' untranslated region (UTR) also associated with BMD and fracture risk in the general population, across multiple genomewide association study (GWAS) meta-analyses (lead variant rs10048745). ARHGAP25 messenger RNA (mRNA) was expressed in macrophage colony-stimulating factor (M-CSF)-stimulated human monocytes and mouse osteoblasts, indicating a possible role for ARHGAP25 in osteoclast and osteoblast differentiation and activity. Studies on subject-derived osteoclasts from peripheral blood mononuclear cells did not reveal robust defects in mature osteoclast formation or resorptive activity. However, analysis of osteosarcoma cells overexpressing the ARHGAP25 G218R-mutant, combined with structural modeling, confirmed that the mutant protein had decreased GAP-activity against Rac1, resulting in elevated Rac1 activity, increased cell spreading, and membrane ruffling. Our findings indicate that mutated ARHGAP25 causes aberrant Rac1 function and consequently abnormal bone metabolism, highlighting the importance of RhoGAP signaling in bone metabolism in familial forms of skeletal fragility and in the general population, and expanding our understanding of the molecular pathways underlying skeletal fragility. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

18.
Nat Commun ; 12(1): 2444, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953184

RESUMO

Osteocytes are master regulators of the skeleton. We mapped the transcriptome of osteocytes from different skeletal sites, across age and sexes in mice to reveal genes and molecular programs that control this complex cellular-network. We define an osteocyte transcriptome signature of 1239 genes that distinguishes osteocytes from other cells. 77% have no previously known role in the skeleton and are enriched for genes regulating neuronal network formation, suggesting this programme is important in osteocyte communication. We evaluated 19 skeletal parameters in 733 knockout mouse lines and reveal 26 osteocyte transcriptome signature genes that control bone structure and function. We showed osteocyte transcriptome signature genes are enriched for human orthologs that cause monogenic skeletal disorders (P = 2.4 × 10-22) and are associated with the polygenic diseases osteoporosis (P = 1.8 × 10-13) and osteoarthritis (P = 1.6 × 10-7). Thus, we reveal the molecular landscape that regulates osteocyte network formation and function and establish the importance of osteocytes in human skeletal disease.


Assuntos
Doenças Ósseas/genética , Homeostase , Osteócitos/metabolismo , Transcriptoma , Fatores Etários , Animais , Doenças Ósseas/metabolismo , Osso e Ossos/metabolismo , Biologia Computacional , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Osteócitos/citologia , Osteoporose/genética , Análise de Sequência de RNA , Fatores Sexuais
20.
Sci Justice ; 61(3): 291-298, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33985677

RESUMO

In a bloodletting incident, the area of origin (AO) of an impact bloodstain pattern is crucial when establishing the sequence of events. The use of laser scanners and other three-dimensional (3D) technologies to document and analyse bloodstains have been the subject of previous papers, especially where AO analysis is concerned. FARO Zone 3D (FZ3D) is a relatively new software programme that can be used for bloodstain AO analysis. FZ3D requires a greater understanding of inter-observer errors associated with AO. This study looked at the inter-observer variation between 21 examiners when repeatedly calculating the AO six times for a single impact pattern on a plain white wall. An impact rig which consisted of a spring tension arm was positioned and fixed 45 cm from the X wall (right wall), and 45 cm from the Y wall (left wall). This experimental design resembles an impact blow for a bloodletting event. The AO was unknown to all examiners, making it a blind study. The collected results were documented in a Microsoft Excel datasheet and later analysed. From previous literature, a 30 cm acceptable allowance was utilised for AO analysis; however, there is currently no accepted standard error for this type of analysis. The overall total 3D mean error for all examiners was 5.62 cm. The maximum error for any one impact analysis was 24.27 cm. The variation of the data, which was collected by all examiners, was documented as X = 1.14 cm, Y = 1.24 cm, Z = 1.68 cm, and the total 3D error = 2.28 cm. The total 3D error for any one examiner and the variance between examiners did not exceed the 30 cm acceptable allowance utilised in previous literature.


Assuntos
Manchas de Sangue , Humanos , Lasers , Variações Dependentes do Observador , Software
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