TBS (trabecular bone score) and diabetes-related fracture risk.

CONTEXT: Type 2 diabetes is associated with increased fracture risk but paradoxically greater bone mineral density (BMD). Trabecular bone score (TBS) is derived from the texture of the spine dual x-ray absorptiometry (DXA) image and is related to bone microarchitecture and fracture risk, providing information independent of BMD. OBJECTIVE: This study evaluated the ability of lumbar spine TBS to account for increased fracture risk in diabetes. DESIGN AND SETTING: We performed a retrospective cohort study using BMD results from a large clinical registry for the province of Manitoba, Canada. Patients: We included 29,407 women 50 years old and older with baseline DXA examinations, among whom 2356 had diagnosed diabetes. MAIN OUTCOME MEASURES: Lumbar spine TBS was derived for each spine DXA examination blinded to clinical parameters and outcomes. Health service records were assessed for incident nontraumatic major osteoporotic fractures (mean follow-up 4.7 years). RESULTS: Diabetes was associated with higher BMD at all sites but lower lumbar spine TBS in unadjusted and adjusted models (all P < .001). The adjusted odds ratio (aOR) for a measurement in the lowest vs the highest tertile was less than 1 for BMD (all P < .001) but was increased for lumbar spine TBS [aOR 2.61, 95% confidence interval (CI) 2.30-2.97]. Major osteoporotic fractures were identified in 175 women (7.4%) with and 1493 (5.5%) without diabetes (P < .001). Lumbar spine TBS was a BMD-independent predictor of fracture and predicted fractures in those with diabetes (adjusted hazard ratio 1.27, 95% CI 1.10-1.46) and without diabetes (hazard ratio 1.31, 95% CI 1.24-1.38). The effect of diabetes on fracture was reduced when lumbar spine TBS was added to a prediction model but was paradoxically increased from adding BMD measurements. CONCLUSIONS: Lumbar spine TBS predicts osteoporotic fractures in those with diabetes, and captures a larger portion of the diabetes-associated fracture risk than BMD.

Staphylococcal biofilm formation on the surface of three different calcium phosphate bone grafts: a qualitative and quantitative in vivo analysis.

Differences in physico-chemical characteristics of bone grafts to fill bone defects have been demonstrated to influence in vitro bacterial biofilm formation. Aim of the study was to investigate in vivo staphylococcal biofilm formation on different calcium phosphate bone substitutes. A foreign-body guinea-pig infection model was used. Teflon cages prefilled with β-tricalcium phosphate, calcium-deficient hydroxyapatite, or dicalcium phosphate (DCP) scaffold were implanted subcutaneously. Scaffolds were infected with 2 × 10(3) colony-forming unit of Staphylococcus aureus (two strains) or S. epidermidis and explanted after 3, 24 or 72 h of biofilm formation. Quantitative and qualitative biofilm analysis was performed by sonication followed by viable counts, and microcalorimetry, respectively. Independently of the material, S. aureus formed increasing amounts of biofilm on the surface of all scaffolds over time as determined by both methods. For S. epidermidis, the biofilm amount decreased over time, and no biofilm was detected by microcalorimetry on the DCP scaffolds after 72 h of infection. However, when using a higher S. epidermidis inoculum, increasing amounts of biofilm were formed on all scaffolds as determined by microcalorimetry. No significant variation in staphylococcal in vivo biofilm formation was observed between the different materials tested. This study highlights the importance of in vivo studies, in addition to in vitro studies, when investigating biofilm formation of bone grafts.

Nouvelles thérapies pour les maladies osseuses de l'enfant [New therapies for children affected by bone diseases].

Considerable progress has been achieved in recent years in treating children affected by bone diseases. Advances in the understanding of the molecular pathophysiology of genetic bone diseases have led to the development of enzyme replacement therapies for various lysosomal storage diseases, following the breakthrough initiated in treating Gaucher disease. Clinical studies are underway with tailored molecules correcting bone fragility and alleviating chronic bone pain and other manifestations of hypophosphatasia, or promoting growth of long bones in achondroplasia patients. We further report our very encouraging experience with intravenous bisphosphonate treatment in children suffering from secondary osteopenia and the high prevalence of calcium and vitamin D deficits in these severely disabled children.

Temporal changes in mRNA expression of the brain nutrient transporters in the lithium-pilocarpine model of epilepsy in the immature and adult rat.

The lithium-pilocarpine model mimics most features of human temporal lobe epilepsy. Following our prior studies of cerebral metabolic changes, here we explored the expression of transporters for glucose (GLUT1 and GLUT3) and monocarboxylates (MCT1 and MCT2) during and after status epilepticus (SE) induced by lithium-pilocarpine in PN10, PN21, and adult rats. In situ hybridization was used to study the expression of transporter mRNAs during the acute phase (1, 4, 12 and 24h of SE), the latent phase, and the early and late chronic phases. During SE, GLUT1 expression was increased throughout the brain between 1 and 12h of SE, more strongly in adult rats; GLUT3 increased only transiently, at 1 and 4h of SE and mainly in PN10 rats; MCT1 was increased at all ages but 5-10-fold more in adult than in immature rats; MCT2 expression increased mainly in adult rats. At all ages, MCT1 and MCT2 up-regulation was limited to the circuit of seizures while GLUT1 and GLUT3 changes were more widespread. During the latent and chronic phases, the expression of nutrient transporters was normal in PN10 rats. In PN21 rats, GLUT1 was up-regulated in all brain regions. In contrast, in adult rats GLUT1 expression was down-regulated in the piriform cortex, hilus and CA1 as a result of extensive neuronal death. The changes in nutrient transporter expression reported here further support previous findings in other experimental models demonstrating rapid transcriptional responses to marked changes in cerebral energetic/glucose demand.

Alterations of bone microarchitecture in young patients with inflammatory bowel diseases are associated with fracture risk during growth

Aims: Inflammatory bowel diseases (IBD) appearing during childhood and adolescence compromise peak bone mass acquisition and increase fracture risk. The structural determinants of bone fragility in IBD however remain unknown. Methods: We investigated volumetric bone mineral density (vBMD), trabecular and cortical bone microstructure at distal radius and tibia by high-resolution pQCT (XtremeCT, Scanco, Switzerland), aBMD at distal radius, hip and spine and vertebral fracture assessment (VFA) by DXA in 107 young patients (mean age 22.8 yrs, range 12.2-33.7 yrs; 62 females and 45 males) with Crohn's disease (n=75), ulcerative colitis (n=25), undetermined colitis (n=2), and no definitive diagnosis (n=5), and in 389 healthy young individuals. Results: Mean disease duration was 6.1 yrs, 89/107 IBD patients received corticosteroids, 83 other immunomodulators, and 59 vitamin D. Clinical fractures were reported by 38 patients (mean age at 1st fracture, 12.6 yrs), the vast majority of the forearm, arm or hand; 5 had vertebral crush fractures (Grade 1 or 2) and 11 had multiple fractures. As compared to healthy controls (matched 2:1 for age, sex, height and fracture history), the 102 patients with established IBD had similar weight but significantly lower aBMD at all sites, lower trabecular (Tb) BV/TV and number, and greater Tb separation and inhomogeneous Tb distribution (1/SD TbN) at both distal radius and tibia, lower tibia cortical thickness (CTh), but no differences in cortical vBMD nor bone perimeter. Among IBD's, aBMD was not associated with fractures (by logistic regression adjusted for age, age square, sex, height, weight and protein intake). However, radius and tibia Tb BV/TV, thickness and SD 1/TbN, as well as radius Tb separation and perimeter, were significantly associated with fracture risk (fully adjusted as above), whereas cortical vBMD and CTh were not. After adjustment for aBMD at radius, respectively at femur neck, radius SD 1/TbN and tibia BV/TV, TbTh and perimeter remained independently associated with fracture risk. Conclusions: Young subjects with IBD have low bone mass and poor bone microarchitecture compared to healthy controls. Alterations of bone microarchitecture, particularly in the trabecular bone compartment, are specifically associated with increased fracture risk during growth.

Trabecular bone score is associated with volumetric bone density and microarchitecture as assessed by central QCT and HRpQCT in Chinese American and white women.

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.

Early Stage Primary Bone Lymphoma: A Retrospective, Multicenter Rare Cancer Network Study

Purpose/Objective(s): Primary bone lymphoma (PBL) represents less than 1% of all malignant lymphomas, and 4-5% of all extranodal lymphomas. In this study, we assessed the disease profile, outcome, and prognostic factors in patients with stage I and II PBL.Materials/Methods: Between 1987 and 2008, 116 consecutive patients with PBL treated in 13 RCNinstitutions were included in this study. Inclusion criteriawere: age.17 yrs, PBLin stage I and II, andminimum6months follow-up. The median agewas 51 yrs (range: 17-93).Diagnosticwork-up included plain boneXray (74%of patients), scintigraphy (62%), CT-scan (65%),MRI (58%), PET (18%), and bone-marrow biopsy (84%).All patients had biopsy-proven confirmation of non-Hodgkin's lymphoma (NHL). The histopathological type was predominantly diffuse large B-cell lymphoma (78%) and follicular lymphoma (6%), according to theWHOclassification. One hundred patients had a high-grade, 7 intermediate and 9 low-gradeNHL. Ninety-three patients had anAnn-Arbor stage I, and 23 had a stage II. Seventy-seven patients underwent chemoradiotherapy (CXRT), 12 radiotherapy (RT) alone, 10 chemotherapy alone (CXT), 9 surgery followed by CXRT, 5 surgery followed by CXT, and 2 surgery followed by RT. One patient died before treatment.Median RT dosewas 40Gy (range: 4-60).Themedian number ofCXTcycleswas 6 (range, : 2-8).Median follow-upwas 41months (range: 6-242).Results: Following treatment, the overall response rate was 91% (CR 74%, PR 17%). Local recurrence was observed in 12 (10%) patients, and systemic recurrence in 17 (15%) patients. Causes of death included disease progression in 16, unrelated disease in 6, CXT-related toxicity in 1, and secondary cancer in 2 patients. The 5-yr overall survival (OS), disease-free survival (DFS), lymphoma- specific survival (LSS), and local control (LC) were 76%, 69%, 78%, and 92%, respectively. In univariate analyses (log-rank test), favorable prognostic factors for survival were: age\50 years (p = 0.008), IPI score #1 (p = 0.009), complete response (p\0.001), CXT (p = 0.008), number of CXT cycles $6 (p = 0.007), and RT dose . 40 Gy (p = 0.005). In multivariate analysis age, RT dose, complete response, and absence of B symptoms were independent factors influencing the outcome. There were 3 patients developing grade 3 or more (CTCAE.V3.0) toxicities.Conclusions: This large multicenter study, confirms the relatively good prognosis of early stage PBL, treated with combined CXRT. Local control was excellent, and systemic failure occurred infrequently. A sufficient dose of RT (. 40 Gy) and completeCXT regime (. 6 cycles) were associated with a better outcome. Combined modality appears to be the treatment of choice.Author Disclosure: L. Cai, None; M.C. Stauder, None; Y.J. Zhang, None; P. Poortmans, None; Y.X. Li, None; N. Constantinou, None; J. Thariat, None; S. Kadish, None; M. Ozsahin, None; R.O. Mirimanoff, None.

Plastic brain mechanisms for attaining auditory temporal order judgment proficiency.

Accurate perception of the order of occurrence of sensory information is critical for the building up of coherent representations of the external world from ongoing flows of sensory inputs. While some psychophysical evidence reports that performance on temporal perception can improve, the underlying neural mechanisms remain unresolved. Using electrical neuroimaging analyses of auditory evoked potentials (AEPs), we identified the brain dynamics and mechanism supporting improvements in auditory temporal order judgment (TOJ) during the course of the first vs. latter half of the experiment. Training-induced changes in brain activity were first evident 43-76 ms post stimulus onset and followed from topographic, rather than pure strength, AEP modulations. Improvements in auditory TOJ accuracy thus followed from changes in the configuration of the underlying brain networks during the initial stages of sensory processing. Source estimations revealed an increase in the lateralization of initially bilateral posterior sylvian region (PSR) responses at the beginning of the experiment to left-hemisphere dominance at its end. Further supporting the critical role of left and right PSR in auditory TOJ proficiency, as the experiment progressed, responses in the left and right PSR went from being correlated to un-correlated. These collective findings provide insights on the neurophysiologic mechanism and plasticity of temporal processing of sounds and are consistent with models based on spike timing dependent plasticity.

Distribuição temporal de imaturos de Odonata (Insecta) associados a Eichhornia azurea (Kunth) na Lagoa do Camargo, Rio Paranapanema, São Paulo

Os objetivos deste trabalho foram registrar a abundância e a riqueza de Odonata associada a Eichhornia azurea, durante o período de março de 2004 a março de 2005, na Lagoa do Camargo, lateral ao Rio Paranapanema - São Paulo, após um pulso de inundação extraordinário e também investigar os fatores ambientais determinantes na distribuição da abundância de Odonata. As maiores abundâncias e riquezas ocorreram na estação seca, sendo que Coenagrionidae foi a família mais abundante e com a maior riqueza de gêneros de todo o período estudado. Esta alta abundância possivelmente ocorreu devido a seu comportamento, como postura dos ovos dentro do tecido das macrófitas e hábito escalador. Aeshnidae e Libellulidae apresentaram baixa abundância principalmente na estação seca. Os principais fatores ambientais que afetaram a distribuição da abundância de Odonata foram a temperatura de superfície da água, a pluviosidade e a biomassa de E. azurea.

Abundance and temporal distribution of Gonioterma exquisita Duckworth (Lepidoptera, Elachistidae, Stenomatinae) on Byrsonima pachyphylla Griseb. (Malpighiaceae) in the Brazilian Cerrado

The seasonal characteristics of the Cerrado region strongly influence food resource predictability and vegetal tissue nutritional content. The aims of this work were to record the abundance and temporal distribution of Gonioterma exquisita Duckworth, 1964 (Lepidoptera, Elachistidae) and its relation with phenological, physical, and chemical traits of the host plant Byrsonima pachyphylla Griseb. (Malpighiaceae). Four nutritional quality parameters were determined for new and mature leaves: gross protein and nitrogen content, dry matter, and in vitro digestibility. We inspected 200 plants per month, searching for G. exquisita caterpillars. About 35.8% of the 2,400 plants inspected presented caterpillars, with an abundance peak in the wet season. Caterpillar abundance was positively correlated with mature leaf availability, their food resource. Although mature leaves presented lower gross protein and nitrogen contents than new leaves, this difference was small during the abundance peak of G. exquisita.

Seasonality and temporal structuration of Alticini community (Coleoptera, Chrysomelidae, Galerucinae) in the Araucaria Forest of Parana, Brazil

Seasonality was studied for Alticini trapped with malaise over a period of two years in the Vila Velha State Park, Parana, Brazil. Coleoptera, Chrysomelidae and Alticini showed seasonal distribution, with the highest abundance during spring and summer months. The abundance peaks of these groups were not synchronized. Of all environmental variables tested, photoperiod had the larger effect on the distributional patterns of Coleoptera, Chrysomelidae and Alticini. Also, Chrysomelidae and Alticini probably are related to the quality and availability of host-plants. When richness was high there was a greater similarity among seasons of different years. However, when richness was not pronounced, seasons showed more similarity within the same year than between years. The Alticini community was seasonally structured and a possible mechanism underlying this pattern is asymmetric competition. Nevertheless, it is necessary to account for indirect interactions (plant-enemy mediated) to better understand how Alticini community is structured.

PPARβ/δ governs Wnt signaling and bone turnover.

Peroxisome proliferator-activated receptors (PPARs) act as metabolic sensors and central regulators of fat and glucose homeostasis. Furthermore, PPARγ has been implicated as major catabolic regulator of bone mass in mice and humans. However, a potential involvement of other PPAR subtypes in the regulation of bone homeostasis has remained elusive. Here we report a previously unrecognized role of PPARβ/δ as a key regulator of bone turnover and the crosstalk between osteoblasts and osteoclasts. In contrast to activation of PPARγ, activation of PPARβ/δ amplified Wnt-dependent and β-catenin-dependent signaling and gene expression in osteoblasts, resulting in increased expression of osteoprotegerin (OPG) and attenuation of osteoblast-mediated osteoclastogenesis. Accordingly, PPARβ/δ-deficient mice had lower Wnt signaling activity, lower serum concentrations of OPG, higher numbers of osteoclasts and osteopenia. Pharmacological activation of PPARβ/δ in a mouse model of postmenopausal osteoporosis led to normalization of the altered ratio of tumor necrosis factor superfamily, member 11 (RANKL, also called TNFSF11) to OPG, a rebalancing of bone turnover and the restoration of normal bone density. Our findings identify PPARβ/δ as a promising target for an alternative approach in the treatment of osteoporosis and related diseases.