RESUMO
Osteoporosis can currently be diagnosed by applying the WHO classification to bone mineral density (BMD) assessed by dual-energy x-ray absorptiometry (DXA). However, skeletal factors other than BMD contribute to bone strength and fracture risk. Lumbar spine TBS, a grey-level texture measure which is derived from DXA images has been extensively studied, enhances fracture prediction independent of BMD and can be used to adjust fracture probability from FRAX® to improve risk stratification. The purpose of this International Society for Clinical Densitometry task force was to review the existing evidence and develop recommendations to assist clinicians regarding when and how to perform, report and utilize TBS. Our review concluded that TBS is most likely to alter clinical management in patients aged ≥ 40 years who are close to the pharmacologic intervention threshold by FRAX. The TBS value from L1-L4 vertebral levels, without vertebral exclusions, should be used to calculate adjusted FRAX probabilities. L1-L4 vertebral levels can be used in the presence of degenerative changes and lumbar compression fractures. It is recommended not to report TBS if extreme structural or pathological artifacts are present. Monitoring and reporting TBS change is unlikely to be helpful with the current version of the TBS algorithm. The next version of TBS software will include an adjustment based upon directly measured tissue thickness. This is expected to improve performance and address some of the technical factors that affect the current algorithm which may require modifications to these Official Positions as experience is acquired with this new algorithm.
Assuntos
Osteoporose , Fraturas por Osteoporose , Humanos , Osso Esponjoso/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico , Medição de Risco/métodos , Osteoporose/diagnóstico por imagem , Osteoporose/patologia , Densidade Óssea , Absorciometria de Fóton/métodos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologiaRESUMO
BACKGROUND: Given the economic relevance of fertility and reproductive traits for the beef cattle industry, investigating their genetic background and developing effective breeding strategies are paramount. Considering their late and sex-dependent phenotypic expression, genomic information can contribute to speed up the rates of genetic progress per year. In this context, the main objectives of this study were to estimate variance components and genetic parameters, including heritability and genetic correlations, for fertility, female precocity, and semen production and quality (andrological attributes) traits in Nellore cattle incorporating genomic information. RESULTS: The heritability estimates of semen quality traits were low-to-moderate, while moderate-to-high estimates were observed for semen morphological traits. The heritability of semen defects ranged from low (0.04 for minor semen defects) to moderate (0.30 for total semen defects). For seminal aspect (SMN_ASPC) and bull reproductive fitness (BULL_FIT), low (0.19) and high (0.69) heritabilities were observed, respectively. The heritability estimates for female reproductive traits ranged from 0.16 to 0.39 for rebreeding of precocious females (REBA) and probability of pregnancy at 14 months (PP14), respectively. Semen quality traits were highly genetically correlated among themselves. Moderate-to-high genetic correlations were observed between the ability to remain productive in the herd until four years of age (stayability; STAY) and the other reproductive traits, indicating that selection for female reproductive performance will indirectly contribute to increasing fertility rates. High genetic correlations between BULL_FIT and female reproductive traits related to precocity (REBA and PP14) and STAY were observed. The genetic correlations between semen quality and spermatic morphology with female reproductive traits ranged from -0.22 (REBA and scrotal circumference) to 0.48 (REBA and sperm vigor). In addition, the genetic correlations between REBA with semen quality traits ranged from -0.23 to 0.48, and with the spermatic morphology traits it ranged from -0.22 to 0.19. CONCLUSIONS: All male and female fertility and reproduction traits evaluated are heritable and can be improved through direct genetic or genomic selection. Selection for better sperm quality will positively influence the fertility and precocity of Nellore females. The findings of this study will serve as background information for designing breeding programs for genetically improving semen production and quality and reproductive performance in Nellore cattle.
Assuntos
Análise do Sêmen , Sêmen , Gravidez , Bovinos/genética , Masculino , Animais , Feminino , Análise do Sêmen/veterinária , Reprodução/genética , Fertilidade/genética , FenótipoRESUMO
Trabecular bone score (TBS) predicts osteoporotic fractures independent of bone mineral density (BMD) and clinical risk factors. The aim of this study was to explore whether anti-resorptive treatment affects fracture risk prediction from TBS using a large clinical registry that includes all dual-energy X-ray absorptiometry (DXA) tests for the Province of Manitoba, Canada. Cohort 1 included 53,863 individuals aged ≥ 40 years (11.4% men; mean age 64.1 years) who had not received any anti-resorptive therapy in the year prior the baseline DXA. Cohort 2 comprised 22,917 individuals aged ≥ 40 years (6% men, mean age 66.7 years) undergoing a second DXA visit. Anti-resorptive medication was initiated in the first year after DXA in 13,439 (25%) individuals from Cohort 1 (87.9% bisphosphonates); among Cohort 2 8,864 (38.7%) had received anti-resorptive medication in the year before DXA (77.8% bisphosphonates). Incident major osteoporotic fracture (MOF), hip fracture and any fracture were identified over mean follow up 8.6 and 7.0 years for Cohorts 1 and 2, respectively. Area under the curve showed significant risk stratification for all fracture types and treatment levels, whether treatment was initiated after TBS measurement (Cohort 1) or prior to TBS measurement (Cohort 2). In Cox regression models, without and with covariate adjustment, fracture prediction from TBS was unaffected by anti-resorptive medication use (p-interaction >0.5 for all analyses). In conclusion, TBS was a robust predictor of fracture in models adjusted for clinical risk factors and BMD. The use of anti-resorptive therapy, either in the year before or following TBS measurement, did not attenuate fracture risk prediction by TBS compared to untreated individuals.
Assuntos
Osso Esponjoso , Fraturas por Osteoporose , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Osso Esponjoso/diagnóstico por imagem , Estudos de Coortes , Vértebras Lombares , Densidade Óssea , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Fraturas por Osteoporose/etiologia , Absorciometria de Fóton , Difosfonatos , Sistema de Registros , Medição de RiscoRESUMO
Both hypoparathyroidism (HypoPT), as well as its pathological counterpart, primary hyperparathyroidism (PHPT), can lead to skeletal abnormalities. Chronic deficiency of PTH in patients with HypoPT is associated with a profound reduction in bone remodeling, with consequent increases in bone density, and abnormalities in microarchitecture and bone strength. It is still not clear whether there is an increase in fracture risk in HypoPT. While standard therapy with calcium supplements and active vitamin D does not restore bone homeostasis, treatment of HypoPT with PTH appears to correct some of those abnormalities. In PHPT, the continuous exposure to high levels of PTH causes an increase in bone remodeling, in which bone resorption prevails. In the symptomatic form of PHPT, patients can present with fragility fractures, and/or the classical radiological features of osteitis fibrosa cystica. However, even in mild PHPT, catabolic skeletal actions of PTH are evident through reduced BMD, deterioration of bone microarchitecture and increased risk of fragility fractures. Successful parathyroidectomy improves skeletal abnormalities. Medical treatment, such as bisphosphonates and denosumab, can also increase bone density in patients with PHPT who do not undergo surgery. This article reviews skeletal involvement in HypoPT and in PHPT, as assessed by bone remodeling, DXA, trabecular bone score, and quantitative computed tomography, as well as data on bone strength and fracture risk. The effects of PTH replacement on the skeleton in subjects with HypoPT, and the outcome of parathyroidectomy in patients with PHPT, are also reviewed here.
Assuntos
Hiperparatireoidismo Primário , Hipoparatireoidismo , Densidade Óssea , Remodelação Óssea , Osso e Ossos/metabolismo , Humanos , Hiperparatireoidismo Primário/complicações , Hipoparatireoidismo/complicações , Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/uso terapêuticoRESUMO
SummaryThe cryopreservation of epididymal sperm is an important technique that allows genetic material to be preserved, even post mortem. However, cryopreservation leads to increased oxidative stress and impaired sperm viability. Polyunsaturated fatty acid (PUFA) supplementation may improve certain sperm characteristics, but it also makes sperm more susceptible to oxidative stress, therefore adding antioxidants that counteract oxidative stress has become an option. In this context, this study aimed to evaluate the effect of the interaction between docosahexaenoic acid (DHA) and antioxidants on the quality after the cryopreservation of epididymal bull sperm. Twenty epididymides were collected after slaughter, and epididymal sperm was cryopreserved with bovine extender supplemented with docosahexaenoic acid (DHA), glutathione peroxidase (GPx) and superoxide dismutase (SOD). We verified an improvement in motility in the group that was treated only with DHA 5 µM and a concentration-dependent effect on susceptibility to lipid peroxidation that was associated with DHA concentration (1 µM, 5 µM or 10 µM). Moreover, treatment with DHA (5 µM) and SOD (20 IU/ml) resulted in higher sperm motility. Thus, the association between DHA (5 µM) and SOD (20 IU/ml) appears to be an option for increased epididymal sperm features in bulls.
Assuntos
Criopreservação/métodos , Ácidos Docosa-Hexaenoicos/farmacologia , Glutationa Peroxidase/farmacologia , Preservação do Sêmen/veterinária , Superóxido Dismutase/farmacologia , Animais , Antioxidantes/farmacologia , Bovinos , Criopreservação/veterinária , Epididimo/citologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Preservação do Sêmen/métodos , Motilidade dos EspermatozoidesRESUMO
The bone marrow niche is thought to act as a permissive microenvironment required for emergence or progression of hematologic cancers. We hypothesized that osteoblasts, components of the niche involved in hematopoietic stem cell (HSC) function, influence the fate of leukemic blasts. We show that osteoblast numbers decrease by 55% in myelodysplasia and acute myeloid leukemia patients. Further, genetic depletion of osteoblasts in mouse models of acute leukemia increased circulating blasts and tumor engraftment in the marrow and spleen leading to higher tumor burden and shorter survival. Myelopoiesis increased and was coupled with a reduction in B lymphopoiesis and compromised erythropoiesis, suggesting that hematopoietic lineage/progression was altered. Treatment of mice with acute myeloid or lymphoblastic leukemia with a pharmacologic inhibitor of the synthesis of duodenal serotonin, a hormone suppressing osteoblast numbers, inhibited loss of osteoblasts. Maintenance of the osteoblast pool restored normal marrow function, reduced tumor burden, and prolonged survival. Leukemia prevention was attributable to maintenance of osteoblast numbers because inhibition of serotonin receptors alone in leukemic blasts did not affect leukemia progression. These results suggest that osteoblasts play a fundamental role in propagating leukemia in the marrow and may be a therapeutic target to induce hostility of the niche to leukemia blasts.
Assuntos
Progressão da Doença , Leucemia/patologia , Osteoblastos/patologia , Animais , Contagem de Células , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Osteoblastos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Pirimidinas/farmacologia , Pirimidinas/uso terapêuticoRESUMO
Bone mineral density (BMD) as measured by dual-energy X-ray absorptiometry (DXA) is the gold standard for the diagnosis and management of osteoporosis. However, BMD explains only 60%-80% of bone strength, and a number of skeletal features other than BMD contribute to bone strength and fracture risk. Advanced imaging modalities can assess some of these skeletal features, but compared to standard DXA, these techniques have higher costs and limited accessibility. A major challenge, therefore, has been to incorporate in clinical practice a readily available, noninvasive technology that permits improvement in fracture-risk prediction beyond that provided by the combination of standard DXA measurements and clinical risk factors. To this end, trabecular bone score (TBS), a gray-level textural index derived from the lumbar spine DXA image, has been investigated. The purpose of this International Society for Clinical Densitometry task force was to review the evidence and develop recommendations on how to incorporate TBS in clinical practice. Clinical applications of TBS for fracture risk assessment, treatment initiation, monitoring of treatment, and use of TBS in special conditions related to greater fracture risk, were addressed. We present the official positions approved by an expert panel following careful review of the recommendations and evidence presented by the TBS task force.
Assuntos
Absorciometria de Fóton , Fraturas Ósseas/etiologia , Vértebras Lombares/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Humanos , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Medição de Risco , Sociedades Médicas , Adulto JovemRESUMO
Individuals with type 2 diabetes have lower trabecular bone score (TBS) and increased fracture risk despite higher bone mineral density. However, measures of trabecular microarchitecture from high-resolution peripheral computed tomography are not lower in type 2 diabetes. We hypothesized that confounding effects of abdominal tissue thickness may explain this discrepancy, since central obesity is a risk factor for diabetes and also artifactually lowers TBS. This hypothesis was tested in individuals aged 40 years and older from a large DXA registry, stratified by sex and diabetes status. When DXA-measured abdominal tissue thickness was not included as a covariate, men without diabetes had lower TBS than women without diabetes (mean difference -0.074, P < .001). TBS was lower in women with versus without diabetes (mean difference -0.037, P < .001), and men with versus without diabetes (mean difference -0.007, P = .042). When adjusted for tissue thickness these findings reversed, TBS became greater in men versus women without diabetes (mean difference +0.053, P < .001), in women with versus without diabetes (mean difference +0.008, P < .001), and in men with versus without diabetes (mean difference +0.014, P < .001). During mean 8.7 years observation, incident major osteoporotic fractures were seen in 7048 (9.6%). Adjusted for multiple covariates except tissue thickness, TBS predicted fracture in all subgroups with no significant diabetes interaction. When further adjusted for tissue thickness, HR per SD lower TBS remained significant and even increased slightly. In conclusion, TBS predicts fractures independent of other clinical risk factors in both women and men, with and without diabetes. Excess abdominal tissue thickness in men and individuals with type 2 diabetes may artifactually lower TBS using the current algorithm, which reverses after accounting for tissue thickness. This supports ongoing efforts to update the TBS algorithm to directly account for the effects of abdominal tissue thickness for improved fracture risk prediction.
Individuals with type 2 diabetes are at increased fracture risk despite having higher bone mineral density (BMD). Previous studies suggest that trabecular bone score (TBS), a measure of bone derived from spine DXA images that can be used to assess fracture risk in addition to BMD, may be lower in individuals with type 2 diabetes. However, TBS is artificially lowered by greater abdominal obesity. We showed that abdominal obesity explained the lower TBS measurements that were seen in individuals with type 2 diabetes. However, even when we considered the effect of abdominal obesity, TBS was still able to predict major fractures in both women and men, with and without diabetes.
Assuntos
Densidade Óssea , Osso Esponjoso , Diabetes Mellitus Tipo 2 , Fraturas Ósseas , Sistema de Registros , Humanos , Masculino , Feminino , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/patologia , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Fatores de Risco , Manitoba/epidemiologia , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/diagnóstico por imagem , Idoso , Adulto , Abdome/diagnóstico por imagem , Abdome/patologiaRESUMO
The Forkhead transcription factor FoxO1 inhibits through its expression in osteoblasts ß-cell proliferation, insulin secretion, and sensitivity. At least part of the FoxO1 metabolic functions result from its ability to suppress the activity of osteocalcin, an osteoblast-derived hormone favoring glucose metabolism and energy expenditure. In searching for mechanisms mediating the metabolic actions of FoxO1, we focused on ATF4, because this transcription factor also affects glucose metabolism through its expression in osteoblasts. We show here that FoxO1 co-localizes with ATF4 in the osteoblast nucleus, and physically interacts with and promotes the transcriptional activity of ATF4. Genetic experiments demonstrate that FoxO1 and ATF4 cooperate to increase glucose levels and decrease glucose tolerance. These effects result from a synergistic effect of the two transcription factors to suppress the activity of osteocalcin through up-regulating expression of the phosphatase catalyzing osteocalcin inactivation. As a result, insulin production by ß-cells and insulin signaling in the muscle, liver and white adipose tissue are compromised and fat weight increases by the FoxO1/ATF4 interaction. Taken together these observations demonstrate that FoxO1 and ATF4 cooperate in osteoblasts to regulate glucose homeostasis.
Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Glucose/metabolismo , Osteoblastos/metabolismo , Fator 4 Ativador da Transcrição/genética , Animais , Proliferação de Células , Células Cultivadas , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/genética , Homeostase , Insulina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Osteoblastos/citologia , Ligação ProteicaRESUMO
Although safe and effective agents are currently available to treat osteoporosis, fragility fractures remain a significant problem worldwide. Recent improvements in the understanding of the cellular, biochemical, and molecular pathways of bone biology have led to the development of newer agents to treat osteoporosis, which may lead to further improvements in outcomes. In this review, we summarize the most recent advances in the field, including new modes of administration of existing drug classes, various approaches to combination therapy, and drugs with novel mechanisms of action to treat osteoporosis.
Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Osteoporose/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Densidade Óssea/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Catepsina K/antagonistas & inibidores , Denosumab , Quimioterapia Combinada , Duodeno/metabolismo , Feminino , Fraturas Ósseas/prevenção & controle , Marcadores Genéticos , Humanos , Imidazóis/uso terapêutico , Hormônio Paratireóideo/uso terapêutico , Ligante RANK/antagonistas & inibidores , Ligante RANK/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Serotonina/metabolismo , Ácido ZoledrônicoRESUMO
Although high-resolution peripheral quantitative computed tomography (HRpQCT) and central quantitative computed tomography (QCT) studies have shown bone structural differences between Chinese American (CH) and white (WH) women, these techniques are not readily available in the clinical setting. The trabecular bone score (TBS) estimates trabecular microarchitecture from dual-energy X-ray absorptiometry spine images. We assessed TBS in CH and WH women and investigated whether TBS is associated with QCT and HRpQCT indices. Areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry, lumbar spine (LS) TBS, QCT of the LS and hip, and HRpQCT of the radius and tibia were performed in 71 pre- (37 WH and 34 CH) and 44 postmenopausal (21 WH and 23 CH) women. TBS did not differ by race in either pre- or postmenopausal women. In the entire cohort, TBS positively correlated with LS trabecular volumetric bone mineral density (vBMD) (r = 0.664), femoral neck integral (r = 0.651), trabecular (r = 0.641) and cortical vBMD (r = 0.346), and cortical thickness (C/I; r = 0.540) by QCT (p < 0.001 for all). TBS also correlated with integral (r = 0.643), trabecular (r = 0.574) and cortical vBMD (r = 0.491), and C/I (r = 0.541) at the total hip (p < 0.001 for all). The combination of TBS and LS aBMD predicted more of the variance in QCT measures than aBMD alone. TBS was associated with all HRpQCT indices (r = 0.20-0.52) except radial cortical thickness and tibial trabecular thickness. Significant associations between TBS and measures of HRpQCT and QCT in WH and CH pre- and postmenopausal women demonstrated here suggest that TBS may be a useful adjunct to aBMD for assessing bone quality.
Assuntos
Absorciometria de Fóton/métodos , Asiático , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Osso e Ossos/metabolismo , Estudos Transversais , Feminino , Fraturas Ósseas/etnologia , Fraturas Ósseas/metabolismo , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco/métodos , Estados Unidos/epidemiologia , População BrancaRESUMO
In this review, we consider new concepts in the assessment of fracture risk and pharmacologic therapy for osteoporosis. We discuss trabecular bone score, a new imaging technology that adds information that cannot be obtained by only measuring bone mineral density by dual-energy x-ray absorptiometry. We also discuss innovations in antiresorptive, osteoanabolic, and combination therapy; and newer therapeutic classes, including cathepsin K inhibitors and antisclerostin antibodies. We do not cover agents that have not yet been studied in human clinical trials or that are no longer under active investigation.
Assuntos
Absorciometria de Fóton/métodos , Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/complicações , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Esquema de Medicação , Quimioterapia Combinada , Humanos , Interpretação de Imagem Assistida por Computador , Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/etiologia , Medição de RiscoRESUMO
Hypoparathyroidism, despite the conventional therapy with calcium and active vitamin D, can lead to skeletal and nonskeletal abnormalities. Chronic hypoparathyroidism is associated with a significant reduction in bone remodeling, increases in areal and volumetric bone density, and improvement in trabecular microarchitecture and in trabecular bone score. Regardless of these advantages in bone mass and microarchitecture, recent data suggest an increased vertebral fracture risk in patients with nonsurgical hypoparathyroidism. Moreover, chronic hypoparathyroidism can lead to abnormalities in multiple organ systems, including the neurological, cardiovascular, renal, neuropsychiatric, ocular, and immune systems. Nephrocalcinosis, nephrolithiasis, and renal insufficiency, as well as decreased quality of life and cataracts, are common in patients with hypoparathyroidism. An increased incidence of hospitalization due to infections and a greater risk of cardiovascular diseases are observed in patients with hypoparathyroidism, particularly in those with nonsurgical disease. All these abnormalities may be because of the disease itself or complications of therapy. We herein reviewed the skeletal and nonskeletal consequences of hypoparathyroidism in patients conventionally managed with calcium and active vitamin D.
Assuntos
Cálcio , Hipoparatireoidismo , Humanos , Qualidade de Vida , Hipoparatireoidismo/complicações , Densidade Óssea , Vitamina D , Hormônio ParatireóideoRESUMO
Osteoporosis, a disease classically attributed to postmenopausal women, is underappreciated, underdiagnosed, and undertreated in men. However, it is not uncommon for osteoporotic fractures to occur in men. About 40% of fractures occur in men with an incidence that has increased over the years. After a first fracture, the risk of a subsequent episode, as well as the risk of death, is higher in the male than in the female population. Despite these facts, only 10% of men with osteoporosis receive adequate treatment. Up to half of the cases of male osteoporosis have a secondary cause, the most common being hypogonadism, excessive alcohol consumption, and chronic use of glucocorticoids. The International Society for Clinical Densitometry (ISCD) recommends using the female database for the diagnosis of osteoporosis by DXA (T-score ≤ -2.5 in men over 50 years old). In addition, osteoporosis can also be diagnosed independently of the BMD if a fragility fracture is present, or if there is a high risk of fractures by FRAX. Treatment is similar to postmenopausal osteoporosis, because the data regarding changes in bone density track closely to those in women. Data concerning fracture risk reduction are not as certain because the clinical trials have included fewer subjects for shorter period of time. In men with symptomatic hypogonadism, testosterone replacement, if indicated, can improve BMD.
Assuntos
Hipogonadismo , Osteoporose Pós-Menopausa , Osteoporose , Fraturas por Osteoporose , Feminino , Masculino , Humanos , Pessoa de Meia-Idade , Osteoporose/complicações , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/diagnóstico , Fraturas por Osteoporose/epidemiologia , Densidade Óssea , Hipogonadismo/complicações , Fatores de Risco , Medição de Risco , Absorciometria de FótonRESUMO
Trabecular bone score (TBS) is an indirect and noninvasive measure of bone quality. A low TBS indicates degraded bone microarchitecture, predicts osteoporotic fracture, and is partially independent of clinical risk factors and bone mineral density (BMD). There is substantial evidence supporting the use of TBS to assess vertebral, hip, and major osteoporotic fracture risk in postmenopausal women, as well as to assess hip and major osteoporotic fracture risk in men aged > 50 years. TBS complements BMD information and can be used to adjust the FRAX (Fracture Risk Assessment) score to improve risk stratification. While TBS should not be used to monitor antiresorptive therapy, it may be potentially useful for monitoring anabolic therapy. There is also a growing body of evidence indicating that TBS is particularly useful as an adjunct to BMD for fracture risk assessment in conditions associated with increased fracture risk, such as type-2 diabetes, chronic corticosteroid excess, and other conditions wherein BMD readings are often misleading. The interference of abdominal soft tissue thickness (STT) on TBS should also be considered when interpreting these findings because image noise can impact TBS evaluation. A new TBS software version based on an algorithm that accounts for STT rather than BMI seems to correct this technical limitation and is under development. In this paper, we review the current state of TBS, its technical aspects, and its evolving role in the assessment and management of several clinical conditions.
Assuntos
Osso Esponjoso , Fraturas por Osteoporose , Masculino , Feminino , Humanos , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Absorciometria de Fóton , Medição de Risco , Densidade Óssea , Vértebras LombaresRESUMO
BACKGROUND: Type 2 diabetes (T2D) is associated with increased fracture risk, despite similar or greater BMD compared to nondiabetics. TBS predicts fracture risk in T2D and nondiabetics. However, increased abdominal thickness, a common feature in T2D, may reduce TBS values. AIM: To study the relationship among glycemic status, BMD and TBS, considering abdominal soft tissue thickness (STT) interference. METHODS: Cross-sectional analysis of 493 women ≥65 years, with simultaneous DXA scans and HbA1c measures. STT and TBS (iNsight Software, v3.0) were derived from lumbar spine (LS) scans. Subjects were divided according to HbA1c levels: 1 (≥6.5%; n = 116), 2 (5.7-6.4%; n = 217) and 3 (≤5.6%; n = 160). Group 1 was further divided based on HbA1c and/or disease duration: 1a (HbA1c ≥ 7.5%; n = 42), 1b (HbA1c ≥ 6.5% and disease duration ≥5 years; n = 63) and 1c (HbA1c ≥ 7.5% and disease duration ≥5 years; n = 30). FINDINGS: For the entire cohort, mean age, TBS, BMI and STT were 71.8 ± 6.0 years, 1.299 ± 0.101, 26.9 ± 4.1 kg/m2, and 21.4 ± 2.9 cm, respectively. LS-BMD was similar among groups. BMD in hip sites and STT were higher in group 1. TBS was lower in patients with higher HbA1c (P = 0.020), with a mean TBS in groups 1, 2, and 3 of 1.280, 1.299 and 1.314, respectively. This difference remained after adjusting for age, LS-BMD and BMI (P = 0.010). After replacing BMI with STT, TBS differences were no longer significant (P = 0.270). The same was observed when subgroups 1a and 1b were compared to group 3. However, for subgroup 1c, TBS remained lower compared to group 3, even after adjusting for age, LS-BMD and STT, with a borderline P-value (1.275 vs. 1.308; P = 0.047). CONCLUSION: Higher HbA1c levels were associated with greater BMD in hip sites, higher abdominal STT and lower TBS values. However, after including the STT in the adjustment, TBS differences among groups disappeared, except in women with higher HbA1c levels and longer disease duration.
Assuntos
Diabetes Mellitus Tipo 2 , Fraturas Ósseas , Fraturas por Osteoporose , Absorciometria de Fóton , Idoso , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Feminino , Fraturas Ósseas/complicações , Hemoglobinas Glicadas , Humanos , Vértebras Lombares/diagnóstico por imagem , Fraturas por Osteoporose/complicações , Pós-MenopausaRESUMO
Several drugs are available for the treatment of osteoporosis in postmenopausal women. Over the last decades, most patients requiring pharmacological intervention were offered antiresorptive drugs as first-line therapy, while anabolic agents were considered a last resource for those with therapeutic failure. However, recent randomized trials in patients with severe osteoporosis have shown that anabolic agents reduce fractures to a greater extent than antiresorptive medications. Additionally, evidence indicates that increases in bone mineral density (BMD) are maximized when patients are treated with anabolic agents first, followed by antiresorptive therapy. This evidence is key, considering that greater increases in BMD during osteoporosis treatment are associated with a more pronounced reduction in fracture risk. Thus, international guidelines have recently proposed an individualized approach to osteoporosis treatment based on fracture risk stratification, in which the stratification risk has been refined to include a category of patients at very high risk of fracture who should be managed with anabolic agents as first-line therapy. In this document, the Brazilian Society of Endocrinology and Metabolism and the Brazilian Association of Bone Assessment and Metabolism propose the definition of very high risk of osteoporotic fracture in postmenopausal women, for whom anabolic agents should be considered as first-line therapy. This document also reviews the factors associated with increased fracture risk, trials comparing anabolic versus antiresorptive agents, efficacy of anabolic agents in patients who are treatment naïve versus those previously treated with antiresorptive agents, and safety of anabolic agents.
Assuntos
Anabolizantes , Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Osteoporose , Fraturas por Osteoporose , Humanos , Feminino , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Anabolizantes/uso terapêutico , Brasil , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Fraturas por Osteoporose/tratamento farmacológico , Densidade ÓsseaRESUMO
Companion animals can carry pathogens that cause many infectious diseases in humans. In this sense, the present study aims to analyse the prevalence of zoonotic intestinal parasites in domiciled dogs living in the urban area of Alfenas, State of Minas Gerais, Brazil, from February 2017 to July 2018. To collect data, four regions of the city were considered as strata and their respective neighbourhoods as conglomerates, and one neighbourhood per stratum was selected. Stool samples were collected from 336 domiciled dogs and processed using the spontaneous sedimentation technique. The dog owners filled a questionnaire with information on the animals' living conditions. The parasites identified were Ancylostoma sp. and Toxocara canis, with higher prevalence of the former in male dogs, and of the latter in female dogs. Dogs of defined breed, small size, and age >1 year old exhibited the highest infection rates. To teach concepts of parasite transmission and prevention, the researchers developed educational actions with 6- to 10-year-old children who studied at schools from the selected neighbourhoods, as well as distributed informative folders to the dog owners. Laboratory tests confirmed the presence of potentially zoonotic intestinal parasites in 2.98% of the domiciled dogs living in Alfenas. Insufficient administration of deworming drugs (p=0.018) was the risk factor that significantly correlated with the occurrence of parasitic infection in the studied dog population. Educational actions favoured adoption of personal hygiene habits and good animal care practices to promote dog health and welfare and human health.
Assuntos
Doenças do Cão , Enteropatias Parasitárias , Parasitos , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Cães , Fezes , Feminino , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/veterinária , Masculino , Prevalência , Zoonoses/epidemiologiaRESUMO
The Montana Tropical® Composite is a recently developed beef cattle population that is rapidly expanding in Brazil and other tropical countries. This is mainly due to its improved meat quality and adaptation to tropical climate conditions compared to Zebu and Taurine cattle breeds, respectively. This study aimed to investigate the genetic architecture of ultrasound-based carcass and meat quality traits in Montana Tropical® Composite beef cattle. Therefore, we estimated variance components and genetic parameters and performed genome-wide association studies using the weighted single-step Genomic Best Linear Unbiased Prediction (GBLUP) approach. A pedigree dataset containing 28,480 animals was used, in which 1,436 were genotyped using a moderate-density Single Nucleotide Polymorphism panel (30K; 30,105 SNPs). A total of 9,358, 5,768, 7,996, and 1,972 phenotypic records for the traits Longissimus muscle area (LMA), backfat thickness (BFT), rump fat thickness (RFT), and for marbling score (MARB), respectively, were used for the analyses. Moderate to high heritability estimates were obtained and ranged from 0.16 ± 0.03 (RFT) to 0.33 ± 0.05 (MARB). A high genetic correlation was observed between BFT and RFT (0.97 ± 0.02), suggesting that a similar set of genes affects both traits. The most relevant genomic regions associated with LMA, BFT, RFT, and MARB were found on BTA10 (5.4-5.8 Mb), BTA27 (25.2-25.5 Mb), BTA18 (60.6-61.0 Mb), and BTA21 (14.8-15.4 Mb). Two overlapping genomic regions were identified for RFT and MARB (BTA13:47.9-48.1 Mb) and for BFT and RFT (BTA13:61.5-62.3 Mb). Candidate genes identified in this study, including PLAG1, LYN, WWOX, and PLAGL2, were previously reported to be associated with growth, stature, skeletal muscle growth, fat thickness, and fatty acid composition. Our results indicate that ultrasound-based carcass and meat quality traits in the Montana Tropical® Composite beef cattle are heritable, and therefore, can be improved through selective breeding. In addition, various novel and already known genomic regions related to these traits were identified, which contribute to a better understanding of the underlying genetic background of LMA, BFT, RFT, and MARB in the Montana Tropical Composite population.
RESUMO
Primary hyperparathyroidism (PHPT), the most common cause of hypercalcemia, is most often identified in postmenopausal women with hypercalcemia and parathyroid hormone (PTH) levels that are either frankly elevated or inappropriately normal. The clinical presentation of PHPT includes three phenotypes: target organ involvement of the renal and skeletal systems; mild asymptomatic hypercalcemia; and more recently, high PTH levels in the context of persistently normal albumin-corrected and ionized serum calcium values. The factors that determine which of these three clinical presentations is more likely to predominate in a given country include the extent to which biochemical screening is employed, the prevalence of vitamin D deficiency, and whether a medical center or practitioner tends to routinely measure PTH levels in the evaluation of low bone density or frank osteoporosis. When biochemical screening is common, asymptomatic primary hyperparathyroidism is the most likely form of the disease. In countries where vitamin D deficiency is prevalent and biochemical screening is not a feature of the health care system, symptomatic disease with skeletal abnormalities is likely to predominate. Finally, when PTH levels are part of the evaluation for low bone mass, the normocalcemic variant is seen. Guidelines for surgical removal of hyperfunctioning parathyroid tissue apply to all three clinical forms of the disease. If guidelines for surgery are not met, parathyroidectomy can also be an appropriate option if there are no medical contraindications to surgery. In settings where either the serum calcium or bone mineral density is of concern, and surgery is not an option, pharmacological approaches are available and effective. Referencing in this article the most current published articles, we review the different presentations of PHPT, with particular emphasis on recent advances in our understanding of target organ involvement and management.