Publications by authors named "Heyer F"

High-resolution peripheral quantitative CT (HR-pQCT) enables quantitative assessment of distal radius fracture healing. In previous studies, lower-mineralized tissue formation was observed on HR-pQCT scans, starting early during healing, but the contribution of this tissue to the stiffness of distal radius fractures is unknown. Therefore, the aim of this study was to investigate the contribution of lower-mineralized tissue to the stiffness of fractured distal radii during the first twelve weeks of healing.

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Vitamin D is an important factor in bone metabolism. Animal studies have shown a positive effect of vitamin D supplementation on fracture healing, but evidence from clinical trials is inconclusive. A randomized controlled trial was performed to assess the effects of vitamin D supplementation on fracture healing using HR-pQCT-based outcome parameters.

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Introduction: Cortical bone thinning and a rarefaction of the trabecular architecture represent possible causes of increased femoral neck (FN) fracture risk. Due to X-ray exposure limits, the bone microstructure is rarely measurable in the FN of subjects but can be assessed at the tibia. Here, we studied whether changes of the tibial cortical microstructure, which were previously reported to be associated with femur strength, are also associated with structural deteriorations of the femoral neck.

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In the human femoral neck, the contribution of the cortical and trabecular architecture to mechanical strength is known to depend on the load direction. In this work, we investigate if QCT-derived homogenized voxel finite element (hvFE) simulations of varying hip loading conditions can be used to study the architecture of the femoral neck. The strength of 19 pairs of human femora was measured ex vivo using nonlinear hvFE models derived from high-resolution peripheral QCT scans (voxel size: 30.

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Purpose: Concomitant chest injury is known to negatively affect bone metabolism and fracture healing, whereas traumatic brain injury (TBI) appears to have positive effects on bone metabolism. Osteogenesis can also be influenced by the timing of fracture stabilization. We aimed to identify how chest injuries, TBI and fracture stabilization strategy influences the incidence of non-union.

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Identifying determinants of long-term functional outcome after a distal radius fracture is challenging. Previously, we reported on the association between early HR-pQCT measurements and clinical outcome 12 weeks after a conservatively treated distal radius fracture. We extended the follow-up and assessed functional outcome after two years in relation to early HR-pQCT derived bone parameters.

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Alterations of structure and density of cortical bone are associated with fragility fractures and can be assessed in vivo in humans at the tibia. Bone remodeling deficits in aging women have been recently linked to an increase in size of cortical pores. In this ex vivo study, we characterized the cortical microarchitecture of 19 tibiae from human donors (aged 69 to 94 years) to address, whether this can reflect impairments of the mechanical competence of the proximal femur, i.

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Cortical pores are determinants of the elastic properties and of the ultimate strength of bone tissue. An increase of the overall cortical porosity (Ct.Po) as well as the local coalescence of large pores cause an impairment of the mechanical competence of bone.

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Fracture healing is characterized by an intense increase in modeling and remodeling of bone, which allows removal of the cast after a stable distal radius fracture within 3 to 5 weeks. However, at that time, bone strength has not recovered yet. We studied the changes in bone mineral density (BMD), microarchitecture, and bone stiffness after a distal radius fracture during a 2-year follow-up in comparison to the contralateral side and the association between the 2-year stiffness and baseline BMD, microarchitecture, and early changes in these parameters.

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Background: Between 5% and 10% of all fractures fail to heal adequately resulting in nonunion of the fracture fragments. This can significantly decrease a patient's quality of life and create associated psychosocial and socio-economic problems. Nitric oxide (NO) and nitric oxide synthases (NOS) have been found to be involved in fracture healing, but until now it is not known if disturbances in these mechanisms play a role in nonunion and delayed union development.

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Histoplasma capsulatum histoplasmosis occurs frequently in endemic areas and with the AIDS outbreak, it appears as an opportunistic fungus involved in disseminated disease. We report the clinical, biological and treatment features of seven cases diagnosed in the CISIH of the Eastern part of Paris. Clinically, four patients were suffering from pulmonary symptoms, in three cases digestive disorders and in three cutaneous lesions.

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This study extends a previous study and confirms that the detection of anti-P30 IgA antibodies is very helpful in the diagnosis of acute acquired or congenital toxoplasmosis. Moreover, we demonstrate that an anti-P30 IgA response can be mounted in the fetuses infected by Toxoplasma gondii during their intra-uterine life as early as week 23 of gestation. A double-sandwich ELISA described in our previous work was used to detect anti-P30 IgA antibodies in 1378 human serum samples collected from 551 patients, including 162 fetuses whose mothers had been infected by T.

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The present study on the focus of schistosomiasis mansoni of Kara (Northern Togo) complements a report already published in the Bulletin de la Société de Pathologie Exotique in 1988 (9). The following results were obtained through different experiments carried out with snails collected in Kara. According to the season, 3 to 15% of the Biomphalaria pfeifferi studied, were infected.

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The purpose of this study was to evaluate the diagnostic value of search for intrathecally synthesized specific antibodies in cerebral toxoplasmosis. Intrathecal synthesis of antibodies was measured by calculating the immunity load coefficient (ILC) in both serum and cerebrospinal fluid. In this retrospective study the records of 42 AIDS patients with clinically on the basis of computerized tomography and therapeutic results, and was excluded in 31 patients (control group).

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In 1985, 374 children of primary schools in North and South Togo were examined and sample of hair were collected on all children with small sterile squares of carpet. 11% of the children in the North (dry and urban area) and 20% in the South (wet and rural area) had obvious clinical lesions. Two species of dermatophytes were isolated: Microsporum langeronii and Trichophyton soudanense; this second dermatophyte being uncommon in the South.

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In 1985 and 1986, an epidemiological survey was carried out in a focus of Schistosoma mansoni located in Kara (Togo). 412 children, 6 months to 15 years old, were examined. The prevalence of schistosomiasis mansoni, evaluated on parasitological and serological data, was of 51.

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