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1.
Osteoporos Int ; 30(12): 2401-2406, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31471665

RESUMO

Clinical practice guidelines provide helpful information for managing patients with metabolic bone disease. Good guidelines are based on the best available medical evidence; however, guidelines from different societies can conflict. Additionally, it is not possible for a guideline to anticipate the vast variability of circumstances, comorbidities, previous medical experiences, cultural differences, and preferences in real-world patients. Bone Health TeleECHO is a strategy for sharing knowledge on the care of patients with skeletal diseases through ongoing interactive videoconferences. We report three cases based on those presented at Bone Health TeleECHO, where, through discussion, treatment outside of commonly used guidelines was ultimately recommended. Guidelines developed by different organizations may provide "evidence-based" or "informed" recommendations which do not account for the variability of clinical circumstances encountered in the care of individual patients. This highlights the importance of Bone Health TeleECHO, where healthcare professionals can share knowledge, individualize treatment decisions, and improve patient care.Learning objectives At the end of this activity participants should be able to:• Distinguish between the onset and off of bisphosphonates versus other medications used in the prevention and treatment of osteoporosis and how this affects choice of a "drug holiday."• Understand the limitations of clinical practices guidelines in the care of an individual patient and how interactive video conferencing can assist with decision making.• Recognize that patients treated with glucocorticoids at high risk for fracture can benefit from more aggressive interventions for osteoporosis.


Assuntos
Tomada de Decisão Clínica/métodos , Osteoporose/tratamento farmacológico , Guias de Prática Clínica como Assunto/normas , Telecomunicações , Idoso , Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Feminino , Glucocorticoides/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/induzido quimicamente
2.
Science ; 365(6455): 817-820, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31439797

RESUMO

The near-Earth asteroid (162173) Ryugu is a 900-m-diameter dark object expected to contain primordial material from the solar nebula. The Mobile Asteroid Surface Scout (MASCOT) landed on Ryugu's surface on 3 October 2018. We present images from the MASCOT camera (MASCam) taken during the descent and while on the surface. The surface is covered by decimeter- to meter-sized rocks, with no deposits of fine-grained material. Rocks appear either bright, with smooth faces and sharp edges, or dark, with a cauliflower-like, crumbly surface. Close-up images of a rock of the latter type reveal a dark matrix with small, bright, spectrally different inclusions, implying that it did not experience extensive aqueous alteration. The inclusions appear similar to those in carbonaceous chondrite meteorites.

3.
Osteoporos Int ; 28(8): 2485-2494, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28536737

RESUMO

Our aim was to evaluate the gap in osteoporosis treatment and the impact of osteoporosis treatment on subsequent fragility fractures. We found osteoporosis medication use lowered risk of subsequent fractures by 21% and that black race, higher CCI scores, dementia, and kidney diseases reduced the likelihood of osteoporosis medication use. INTRODUCTION: The goal of this study was to evaluate the predictors of osteoporosis medication use and compare the risk of fragility fractures within 1 year of a fragility fracture between osteoporosis treated and untreated women. METHODS: We conducted a retrospective, observational cohort study using the national Medicare database. Elderly women (≥65 years) who were hospitalized or had an outpatient/ER service for fragility fracture between January 1, 2011 and December 31, 2011 were included. The outcomes of interest were the correlates of and time-to-osteoporosis medication use and risk of a subsequent fracture within 12 months for treated and untreated women. Cox regression was used to evaluate the predictors of treatment use and the risk of fracture based on treatment status. RESULTS: Women (28,722) (27.7%) were treated with osteoporosis medication within 12 months of index fracture, and 74,979 (72.2%) were untreated. A number of patient characteristics were associated with a reduced likelihood of osteoporosis medication use, including black race, higher Charlson comorbidity index scores, presence of dementia, and kidney diseases in the baseline. The predictor most strongly and positively associated with osteoporosis medication use after fracture was osteoporosis medication use before fragility fracture (HR = 7.87; 95% CI 7.67-8.07). After adjusting for baseline characteristics, osteoporosis medication use lowered the risk of subsequent fractures by 21% (HR = 0.79, 95% CI 0.75-0.83) over 12 months compared to women without treatment. CONCLUSIONS: Demographics and clinical characteristics were strong predictors of osteoporosis medication use. In the US Medicare population, osteoporosis treatment significantly reduced the risk of fragility fractures.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/uso terapêutico , Bases de Dados Factuais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Medicare/estatística & dados numéricos , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Recidiva , Estudos Retrospectivos , Medição de Risco/métodos , Sensibilidade e Especificidade , Estados Unidos/epidemiologia
4.
Osteoporos Int ; 28(6): 1857-1866, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28175980

RESUMO

Spine fracture prevalence is similar in men and women, increasing from <5 % in those <60 to 11 % in those 70-79 and 18 % in those ≥80 years. Prevalence was higher with age, lower bone mineral density (BMD), and in those meeting criteria for spine imaging. Most subjects with spine fractures were unaware of them. INTRODUCTION: Spine fractures have substantial medical significance but are seldom recognized. This study collected contemporary nationally representative spine fracture prevalence data. METHODS: Cross-sectional analysis of 3330 US adults aged ≥40 years participating in NHANES 2013-2014 with evaluable Vertebral Fracture Assessment (VFA). VFA was graded by semiquantitative measurement. BMD and an osteoporosis questionnaire were collected. RESULTS: Overall spine fracture prevalence was 5.4 % and similar in men and women. Prevalence increased with age from <5 % in those <60 to 11 % in those 70-79 and 18 % in those ≥80 years. Fractures were more common in non-Hispanic whites and in people with lower body mass index and BMD. Among subjects with spine fracture, 26 % met BMD criteria for osteoporosis. Prevalence was higher in subjects who met National Osteoporosis Foundation (NOF) criteria for spine imaging (14 vs 4.7 %, P < 0.001). Only 8 % of people with a spine fracture diagnosed by VFA had a self-reported fracture, and among those who self-reported a spine fracture, only 21 % were diagnosed with fracture by VFA. CONCLUSION: Spine fracture prevalence is similar in women and men and increases with age and lower BMD, although most subjects with spine fracture do not meet BMD criteria for osteoporosis. Since most (>90 %) individuals were unaware of their spine fractures, lateral spine imaging is needed to identify these women and men. Spine fracture prevalence was threefold higher in individuals meeting NOF criteria for spine imaging (∼1 in 7 undergoing VFA). Identifying spine fractures as part of comprehensive risk assessment may improve clinical decision making.


Assuntos
Fraturas por Osteoporose/epidemiologia , Fraturas da Coluna Vertebral/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fraturas por Osteoporose/fisiopatologia , Prevalência , Distribuição por Sexo , Fraturas da Coluna Vertebral/fisiopatologia , Estados Unidos/epidemiologia
5.
Oncogene ; 36(19): 2750-2761, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27941880

RESUMO

Mutations in mismatch repair (MMR) genes result in microsatellite instability (MSI) and early onset of colorectal cancer. To get mechanistic insights into the time scale, sequence and frequency of intestinal stem cell (ISC) transformation, we quantified MSI and growth characteristics of organoids of Msh2-deficient and control mice from birth until tumor formation and related them to tissue gene expression. Although in Msh2-deficient organoids MSI continuously increased from birth, growth characteristics remained stable at first. Months before tumor onset, normal Msh2-deficient tissue contained tumor precursor cells forming organoids with higher MSI, cystic growth and growth rates resembling temporarily those of tumor organoids. Consistently, Msh2-deficient tissue exhibited a tumor-like gene signature. Normal Msh2-deficient organoids showed increased inheritable transient cyst-like growth, which became independent of R-spondin. ISC transformation proceeded faster in vitro than in vivo independent of the underlying genotype but more under MMR deficiency. Transient cyst-like growth but not MSI was suppressed by aspirin. In summary, as highlighted by organoids, molecular alterations continuously proceeded long before tumor onset in MMR-deficient intestine, thus increasing its susceptibility for ISC transformation.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA/genética , Instabilidade de Microssatélites , Proteína 2 Homóloga a MutS/genética , Animais , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Reparo do DNA/genética , Mutação em Linhagem Germinativa/genética , Humanos , Intestinos/crescimento & desenvolvimento , Intestinos/patologia , Camundongos , Camundongos Knockout , Células-Tronco Neoplásicas/patologia
6.
Int J Obes (Lond) ; 40(12): 1832-1840, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27460604

RESUMO

BACKGROUND: The genetic architecture of obesity is multifactorial. We have previously identified a quantitative trait locus (QTL) on rat chromosome 10 in a F2 cross of Wistar Ottawa Karlsburg (WOKW) and Dark Agouti (DA) rats responsible for obesity-related traits. The QTL was confirmed in congenic DA.WOKW10 rats. To pinpoint the region carrying causal genes, we established two new subcongenic lines, L1 and L2, with smaller refined segments of chromosome 10 to identify novel candidate genes. METHODS: All lines were extensively characterized under different diet conditions. We employed transcriptome analysis in visceral adipose tissue (VAT) by RNA-Seq technology to identify potential underlying genes in the segregating regions. Three candidate genes were measured in human paired samples of VAT and subcutaneous (SC) AT (SAT) (N=304) individuals with a wide range of body weight and glucose homeostasis parameters. RESULTS: DA.WOKW and L1 subcongenic lines were protected against body fat gain under high-fat diet (HFD), whereas L2 and DA had significantly more body fat after high-fat feeding. Interestingly, adipocyte size distribution in SAT and epigonadal AT of L1 subcongenic rats did not undergo typical ballooning under HFD and the number of preadipocytes in AT was significantly elevated in L2 compared with L1 and parental rats. Transcriptome analysis identified three candidate genes in VAT on rat chromosome 10. In humans, these candidate genes were differentially expressed between SAT and VAT. Moreover, HID1 mRNA significantly correlates with parameters of obesity and glucose metabolism. CONCLUSIONS: Our data suggest novel candidate genes for obesity that map on rat chromosome 10 in an interval 102.2-104.7 Mb and are strongly associated with body fat mass regulation, preadipocyte number and adipocyte size in rats. Among those genes, AT head involution defective (HID1) mRNA expression may be relevant for human fat distribution and glucose homeostasis.


Assuntos
Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo/patologia , Cromossomos de Mamíferos/genética , Obesidade/metabolismo , Células-Tronco/patologia , Animais , Contagem de Células , Tamanho Celular , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Técnicas Genéticas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/patologia , Locos de Características Quantitativas , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
8.
Osteoporos Int ; 27(3): 1191-1198, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26556737

RESUMO

SUMMARY: In patients in the Direct Assessment of Nonvertebral Fractures in Community Experience (DANCE) observational study with and without a prior vertebral or hip fracture, the incidence of nonvertebral fractures was lower with >6 months of teriparatide treatment than during the first 6 months. INTRODUCTION: Clinical evidence on the effect of teriparatide in patients with prior fracture is limited. In the DANCE observational study, the incidence of nonvertebral fragility fractures (NVFX) decreased significantly in patients receiving teriparatide for >6 months (6-24 months) versus >0 to ≤6 months (reference period). METHODS: We performed a post hoc analysis to assess the effect of teriparatide 20 µg/day in patients who entered DANCE with prior vertebral or hip fractures. The incidence of patients experiencing a NVFX for four 6-month intervals during and after treatment was compared with the reference period. RESULTS: Overall, 4085 patients received ≥1 dose of teriparatide. Of 3720 with sufficient data for efficacy analysis, 692 had prior vertebral fracture, including 179 with previous kyphoplasty/vertebroplasty; 290 had prior hip fracture. These patients were older, and those with prior vertebral fractures had more comorbid conditions at baseline than those without prior vertebral fractures. The incidence of patients experiencing NVFX declined over time in all patient groups. The fracture incidence rate declined 49 and 46%, respectively, in patients with and without prior vertebral fracture and was 63 and 46% lower in patients with previous kyphoplasty/vertebroplasty and without prior vertebral fracture. NVFX declined 43 and 48% in patients with and without prior hip fracture. The reduced incidence over time was consistent in the subgroups (all interaction p values >0.05). Patients with prior fracture were more likely to experience serious adverse events. CONCLUSION: The incidence of NVFX decreased over time in patients receiving teriparatide in DANCE regardless of prior fracture status.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Teriparatida/uso terapêutico , Conservadores da Densidade Óssea/efeitos adversos , Feminino , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/prevenção & controle , Humanos , Incidência , Masculino , Osteoporose/epidemiologia , Fraturas por Osteoporose/epidemiologia , Recidiva , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/prevenção & controle , Teriparatida/efeitos adversos , Estados Unidos/epidemiologia
9.
Q J Nucl Med Mol Imaging ; 59(1): 95-104, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25737423

RESUMO

[18F]-3'-fluoro-3'-deoxythymidine (FLT) is a nucleoside-analog imaging agent for quantifying cellular proliferation that was first reported in 1998. It accumulates during the S-phase of the cell cycle through the action of cytosolic thymidine kinase, TK1. Since TK1 is primarily expressed in dividing cells, FLT uptake is essentially limited to dividing cells. Thus FLT is an effective measure of cell proliferation. FLT uptake has been shown to correlate with the more classic proliferation marker, the monoclonal antibody to Ki-67. Increased cellular proliferation is known to correlate with worse outcome in many cancers. However, the Ki-67 binding assay is performed on a sampled preparation, ex vivo, whereas FLT can be quantitatively measured in vivo using positron emission tomography (PET). FLT is an effective and quantitative marker of cell proliferation, and therefore a useful prognostic predictor in the setting of neoplastic disease. This review summarizes clinical studies from 2011 forward that used FLT-PET to assess tumor response to therapy. The paper focuses on our recommendations for a standardized clinical trial protocol and components of a report so multi center studies can be effectively conducted, and different studies can be compared. For example, since FLT is glucuronidated by the liver, and the metabolite is not transported into the cell, the plasma fraction of FLT can be significantly changed by treatment with particular drugs that deplete this enzyme, including some chemotherapy agents and pain medications. Therefore, the plasma level of metabolites should be measured to assure FLT uptake kinetics can be accurately calculated. This is important because the flux constant (KFLT) is a more accurate measure of proliferation and, by inference, a better discriminator of tumor recurrence than standardized uptake value (SUVFLT). This will allow FLT imaging to be a specific and clinically relevant prognostic predictor in the treatment of neoplastic disease.


Assuntos
Didesoxinucleosídeos/farmacocinética , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Timidina Quinase/metabolismo , Proliferação de Células , Humanos , Imagem Molecular/métodos , Compostos Radiofarmacêuticos/farmacocinética
10.
Biochim Biophys Acta ; 1833(12): 2703-2713, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23886630

RESUMO

We recently identified several Ca(2+)-binding proteins (CaBP) from the S100 and annexin family to be regulated by TSH in FRTL-5 cells. Here, we study the regulation of S100A4, S100A6 and ANXA2 in primary human thyrocytes (PHT) derived from surrounding tissues (ST), cold benign thyroid nodules (CTN) and autonomously functioning thyroid nodules (AFTN). We investigated the expression and regulation of CaBP and the effect of their expression on Ca(2+) and TSHR signaling. We used an approach that accounts for the potential of an individual PHT culture to proliferate or to express thyroid differentiation features by assessing the expression of FOS and TPO. We found a strong correlation between the regulation of CaBP and the proliferation-associated transcription factor gene FOS. PKA and MEK1/2 were regulators of ANXA2 expression, while PI3-K and triiodothyronine were additionally involved in S100 regulation. The modulated expression of CaBP was reflected by changes in ATP-elicited Ca(2+) signaling in PHT. S100A4 increased the ratio of subsequent Ca(2+) responses and showed a Ca(2+) buffering effect, while ANXA2 affected the first Ca(2+) response to ATP. Overexpression of S100A4 led to a reduced activation of NFAT by TSH. Using S100A4 E33Q, D63N, F72Q and Y75K mutants we found that the effects of S100A4 expression on Ca(2+) signaling are mediated by protein interaction. We present evidence that TSH has the ability to fine-tune Ca(2+) signals through the regulation of CaBP expression. This represents a novel putative cross-regulating mechanism in thyrocytes that could affect thyrocyte signaling and physiology.


Assuntos
Anexina A2/metabolismo , Cálcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas S100/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Anexina A2/genética , Biomarcadores/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Células Cultivadas , Motivos EF Hand , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Mutantes/metabolismo , Fatores de Transcrição NFATC/metabolismo , Ligação Proteica/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Tireotropina/metabolismo , Proteína A6 Ligante de Cálcio S100 , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas S100/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Glândula Tireoide/efeitos dos fármacos , Tireotropina/farmacologia , Fator de Transcrição AP-1/metabolismo , Tri-Iodotironina/farmacologia
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