The finding that nonspecific supportive clinical management was superior to more specialized psychotherapies was opposite to the primary hypothesis and challenges assumptions about the effective ingredients of successful treatments for anorexia nervosa.
Bone formation in mammals requires continuous production of osteoblasts throughout life. A common molecular marker for all osteogenic mesenchymal progenitors has not been identified. Here, by lineage-tracing experiments in fetal or postnatal mice, we discover that Gli1+ cells progressively produce osteoblasts in all skeletal sites. Most notably, in postnatal growing mice, the Gli1+ cells residing immediately beneath the growth plate, termed here “metaphyseal mesenchymal progenitors” (MMPs), are essential for cancellous bone formation. Besides osteoblasts, MMPs also give rise to bone marrow adipocytes and stromal cells in vivo. RNA-seq reveals that MMPs express a number of marker genes previously assigned to mesenchymal stem/progenitor cells, including CD146/Mcam, CD44, CD106/Vcam1, Pdgfra, and Lepr. Genetic disruption of Hh signaling impairs proliferation and osteoblast differentiation of MMPs. Removal of β-catenin causes MMPs to favor adipogenesis, resulting in osteopenia coupled with increased marrow adiposity. Finally, postnatal Gli1+ cells contribute to both chondrocytes and osteoblasts during bone fracture healing. Thus Gli1 marks mesenchymal progenitors responsible for both normal bone formation and fracture repair.
People with diabetes have increased risk of fracture disproportionate to BMD, suggesting reduced material strength (quality). We quantified the skeletal effects of type 1 diabetes in the rat. Fischer 344 and Sprague-Dawley rats (12 wk of age) were injected with either vehicle (Control) or streptozotocin (Diabetic). Forelimbs were scanned at 0, 4, 8, and 12 wk using pQCT. Rats were killed after 12 wk. We observed progressive osteopenia in diabetic rats. Trabecular osteopenia was caused by bone loss: volumetric BMD decreased progressively with time in diabetic rats but was constant in controls. Cortical osteopenia was caused by premature arrest of cortical expansion: cortical area did not increase after 4-8 wk in diabetic rats but continued to increase in controls. Postmortem mCT showed a 60% reduction in proximal tibial trabecular BV/TV in diabetic versus control rats, whereas moments of inertia of the ulnar and femoral diaphysis were reduced ;30%. Monotonic bending tests indicated that ulna and femora from diabetic animals were ;25% less stiff and strong versus controls. Estimates of material properties indicated no changes in elastic modulus or ultimate stress but modest (;10%) declines in yield stress for diabetic bone. These changes were associated with a ;50% increase in the nonenzymatic collagen cross-link pentosidine. Last, cyclic testing showed diminished fatigue life in diabetic bones at the structural (force) level but not at the material (stress) level. In summary, type 1 diabetes, left untreated, causes trabecular bone loss and a reduction in diaphyseal growth. Diabetic bone has greatly increased nonenzymatic collagen cross-links but only modestly reduced material properties. The loss of whole bone strength under both monotonic and fatigue loading is attributed mainly to reduced bone size.
Objective: The first objective of this paper was to describe the pattern of remission, response and recovery in patients with major depression who were randomised for treatment with fluoxetine or nortriptyline. The second objective was to report on the demographic and diagnostic predictors of the response and recovery in these depressed patients. Method: One hundred and ninety-five patients with major depression were recruited for this outpatient study. After a detailed clinical and neurobiological evaluation patients were randomized to receive either fluoxetine or nortiptyline as an initial antidepressant treatment. Results: Of the 195 depressed patients randomised to treatment, 154 completed an adequate 6-week trial of either fluoxetine or nortriptyline as their initial antidepressant. Of the 41 patients who did not complete an adequate trial the dropout rate was higher on those randomized to nortriptyline (p = 0.02). There was also an important interaction of drug and gender in determining dropouts in that women did not complete an adequate trial with nortriptyline and men did not complete an adequate trial with fluoxetine (p = 0.002). Of the 154 patients who completed an adequate 6-week antidepressant trial there were no significant differences in 6-week measures of depression severity or of percentage improvement. However, if we use an intention to treat analysis and dichotomise outcomes into response, remission or recovery; then recovery rates were significantly higher with fluoxetine than nortriptyline (p = 0.005). Using an intention to treat analysis fluoxetine was superior to nortriptyline in women, in those less than 25-years old, and in those with atypical depression. Independent of drug, those with chronic depressions had a poorer outcome. Conclusion: In this sample of depressed patients randomized to nortriptyline or fluoxetine the change in depressive symptoms over 6 weeks were comparable between fluoxetine and nortriptyline. However, when we look at the more clinically important variable of recovery then fluoxetine was superior to nortriptyline. Predictors of a poorer response to nortriptyline were gender, young age and atypical depression. The results challenge traditional beliefs that selective serotonin re-uptake inhibitors (SSRIs) and tricyclic antidepressant have comparable efficacy.
Osteogenesis occurs by formation of woven or lamellar bone. Little is known about the molecular regulation of these two distinct processes. We stimulated periosteal bone formation at the ulnar mid-diaphysis of adult rats using a single bout of forelimb compression. We hypothesized that loading that stimulates woven bone formation induces higher over-expression of genes associated with cell proliferation, angiogenesis and osteogenesis compared to loading that stimulates lamellar bone formation. We first confirmed that a single bout of 100 cycles of loading using either a restinserted (0.1 Hz) or haversine (2 Hz) waveform (15 N peak force) was non-damaging and increased lamellar bone formation (LBF loading). Woven bone formation (WBF loading) was stimulated using a previously described, damaging fatigue loading protocol (2 Hz, 1.3 mm disp., 18 N peak force). There were dramatic differences in gene expression levels (based on qRT-PCR) between loading protocols that produced woven and lamellar bone. In contrast, gene expression levels were not different between LBF loading protocols using a rest-inserted or haversine waveform. Cell proliferation markers Hist4 and Ccnd1 were strongly upregulated (5-to 17-fold) 1 and 3 days after WBF loading, prior to woven bone formation, but not after LBF loading. The angiogenic genes Vegf and Hif1a were upregulated within 1 hr after WBF loading and were strongly up on days 1-3 (3-to 15-fold). In sharp contrast, we observed only a modest increase (< 2-fold) in Vegfa and Hif1a expression on day 3 following LBF loading. Consistent with these relative differences in gene expression, vascular perfusion 3 days after loading revealed significant increases in vessel number and volume following WBF loading, but not after LBF loading. Lastly, bone formation markers (Runx2, Osx, Bsp) were more strongly upregulated for woven (4-to 89-fold) than for lamellar bone (2-fold), consistent with the differences in new bone volume observed 10 days after loading. In summary, robust early increases both molecularly and histologically for cell proliferation and angiogenesis precede woven bone formation, whereas lamellar bone formation is associated with only a modest upregulation of molecular signals at later timepoints.
Possible effective components of SSCM are discussed.
Objective: To evaluate the long-term efficacy of three psychotherapies for anorexia nervosa.Method: Participants were women with broadly defined anorexia nervosa who had participated in a RCT comparing specialized psychotherapies (cognitive behavior therapy, CBT, and interpersonal psychotherapy, IPT) with a control condition (specialist supportive clinical management, SSCM), and attended long-term follow-up assessment (mean 6.7 years 6 1.2).Results: Forty three of the original sample of 56 women participated in longterm follow-up assessment (77%). No significant differences were found on any pre-selected primary, secondary or tertiary outcome measures among the three psychotherapies at long-term follow-up assessment. Significantly different patterns of recovery were identified for the psychotherapies across time on the primary global outcome measure. Although SSCM was associated with a more rapid response than IPT, by follow-up all three treatments were indistinguishable.Discussion: Potential implications for the timing of interventions to improve treatment response in anorexia nervosa are critically examined. V V C 2010 by Wiley Periodicals, Inc.
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