Dramatic increase in cortical thickness induced by femoral marrow ablation followed by a 3‐month treatment with PTH in rats

We previously reported that following mechanical ablation of the marrow from the midshaft of rat femurs, there is a rapid and abundant but transient growth of bone, and this growth is enhanced and maintained over a 3‐week period by the bone anabolic hormone parathyroid hormone (PTH). Here, we asked whether further treatment with PTH or bisphosphonates can extend the half‐life of the new bone formed in lieu of marrow. We subjected the left femur of rats to mechanical marrow ablation and treated the animals 5 days a week with PTH for 3 weeks (or with vehicle as a control) to replace the marrow by bone. Some rats were euthanized and used as positive controls or treated with vehicle, PTH, or the bisphosphonate alendronate for a further 9 weeks. We subjected both femurs from each rat to soft X‐ray, peripheral quantitative computed tomography (pQCT), micro‐computed tomography (µCT), dynamic histomorphometry analysis, and biomechanical testing. We also determined the concentrations of serum osteocalcin to confirm the efficacy of PTH. Treatment with PTH for 3 months dramatically enhanced endosteal and periosteal bone formation, leading to a 30% increase in cortical thickness. In contrast, alendronate protected the bone that had formed in the femoral marrow cavity after marrow ablation and 3 weeks of treatment with PTH but failed to promote endosteal bone growth or to improve the biomechanical properties of ablated femurs. We further asked whether calcium‐phosphate cements could potentiate the formation of bone after marrow ablation. Marrow cavities from ablated femurs were filled with one of two calcium‐phosphate cements, and rats were treated with PTH or PBS for 84 days. Both cements helped to protect the new bone formed after ablation. To some extent, they promoted the formation of bone after ablation, even in the absence of any anabolic hormone. Our data therefore expand the role of PTH in bone engineering and open new avenues of investigation to the field of regenerative medicine and tissue engineering. Local bone marrow aspiration in conjunction with an anabolic agent, a bisphosphonate, or a calcium‐phosphate cement might provide a new platform for rapid preferential site‐directed bone growth in areas of high bone loss. © 2010 American Society for Bone and Mineral Research     

Immunomonitoring of graft‐versus‐host minor histocompatibility antigen correlates with graft‐versus‐host disease and absence of relapse after graft

BACKGROUND: After HLA‐identical hematopoietic stem cell transplantation, minor histocompatibility (mH) antigen alloreactivity plays a dominant role in the development of graft‐versus‐host disease (GVHD) and graft versus leukemia (GVL). STUDY DESIGN AND METHODS: We have analyzed the mH alloreactivity (enzyme‐linked immunospot [ELISpot] for interferon‐γ[IFN‐γ] assay) from 24 donor/recipient pairs over a period of 2 years of follow‐up and correlated such alloreactivity with the development of GVHD or absence of relapse. Circulating specific T cells anti‐mH with multimer HLA‐peptides were also studied. RESULTS: We show by ELISpot IFN‐γ assay that alloreactivity during the first 3 months from donor versus recipient or donor versus mismatched identified mH antigens is associated with acute GVHD and GVL effect. In addition, we demonstrate that the donor‐versus‐recipient reactivity observed after the third month is highly associated with chronic GVHD and GVL (p = 0.0007). Finally, we show by multimer HLA‐peptide assay that mH epitope‐specific T cells present after 3 months are statistically related to the GVL effect. CONCLUSIONS: Our results provide a robust method to monitor mH antigen graft‐versus‐host reaction and suggest that current identified mH have predictive value on GVHD and GVL.     

The METEOR study of diabetes and other metabolic disorders in patients with schizophrenia treated with antipsychotic drugs. I. Methodology

Patients with schizophrenia present a two‐ to three‐fold higher prevalence of diabetes, of metabolic syndrome and of cardiovascular morbidity. The reason for this increased prevalence may involve intrinsic vulnerability, lifestyle factors and iatrogenic effects of antipsychotic drugs. The objective of this multinational, cross‐sectional, pharmacoepidemiological study was to determine the prevalence of diabetes, lipid disorders, obesity, hypertension and the metabolic syndrome in patients with schizophrenia treated with antipsychotic drugs. Particular attention was taken to acquire data on a wide a range as possible of demographic, clinical and lifestyle variables that may influence the risk of metabolic disorders, which were taken into account in the calculation of prevalence data by propensity scoring. The study included 2270 subjects from 16 European countries, predominantly from Central and Eastern Europe. The proportion of subjects presenting the pathologies of interest was relatively high, ranging from 28% for glycaemic disorders to 70% for lipid disorders. Copyright © 2010 John Wiley & Sons, Ltd.     

Relationships among cognitive function, fine motor speed and age in the rhesus monkey

Declines in fine motor skills and cognitive function are well known features of human aging. Yet, the relationship between age-related impairments in motor and cognitive function remains unclear. Rhesus monkeys, like humans, show marked decline in cognitive and fine motor function with age and are excellent models to investigate potential interactions between age-related declines in cognitive and motor functioning. We investigated the relationships among cognition, motor function and age in 30 male and female rhesus monkeys, 5–28 years of age, tested on a battery of cognitive tasks [acquisition of the delayed non-matching-to-sample (DNMS), DNMS-120s, DNMS-600s, acquisition of delayed recognition span test (DRST), spatial-DRST and object-DRST] and a fine motor task (Lifesaver test). Global cognitive ability, as assessed by the cognitive performance index (CPI), was impaired with age in both sexes, while age-related motor slowing was found only in males. After age was controlled for, half the variance in CPI was predicted by motor speed, with better cognitive ability associated with slower motor skills. Analyses at the level of each cognitive task revealed that motor speed and age predicted the rate of acquisition of the DNMS. This relationship was robust in males and absent in females. Motor speed was not a significant predictor of any other cognitive variable. We conclude that the relationship between cognition and motor function (1) may be limited to non-spatial tasks; (2) exists independently of age; (3) may reflect different contributions of the fronto-striatal system; (4) may be particularly evident in males.     

Treatment of collagen‐induced arthritis by Natura‐α via regulation of Th‐1/Th‐17 responses

Cytokines and CD4⁺ Th cells play a crucial role in the pathogenesis of rheumatoid arthritis. Among the Th populations, Th‐1 and Th‐17 have been described as pathogenic in collagen‐induced arthritis (CIA) whereas Th‐2 and Treg were found to have protective effects. The objective of this study was to examine the affect of Natura‐α, a newly developed cytokine regulator, on CIA and on Th cell development. Natura‐α treatment was administered before or during arthritis induction. Anti‐type II collagen antibodies and cytokine expression were evaluated by ELISA. Emergence of CD4⁺CD25⁺Foxp3⁺ T cells was assessed by flow cytometry. Th‐17 differentiation of naive CD4 T cells was assessed in cultures with anti‐CD3 and anti‐CD28. We showed that Natura‐α both prevented and treated CIA. We further demonstrated that in vivo treatment with Natura‐α inhibited IL‐17 production and anti‐type II collagen IgG development. We showed in vitro, using an APC‐free system, that Natura‐α acted directly on differentiating T cells and inhibiting the formation of Th‐1 and Th‐17 cells but did not affect Th‐2 cells. Since Natura‐α inhibits a large spectrum of important pathogenic factors in CIA, it may provide a new and powerful approach to the treatment of rheumatoid arthritis and other inflammatory diseases.