Bone mineral mass and bone turnover parameters in osteoporosis

In the past decades osteoporosis has been recognized as an important public health problem. Several causes for this problem can be pointed out. The most probable cause for the development of osteoporosis is the loss of ovarian function in women and the increasing age of people, thereby increasing the incidence of osteoporosis. Other causes or risk factors for the development of osteoporosis are immobilization and dietary deficiencies. Finally, the outcome of osteoporosis is an increased risk for the development of fractures (chapter 1.3). The terminology associated with osteoporosis was developed in the nineteenth century by German pathologists to distinguish diseases of bone. Pommer stated in 1926 that in osteoporosis the formation of bone by osteoblasts was not able to replace the bone resorbed by osteoclasts. Pommer performed extensive histomorphometric analysis of bone, thereby distinguishing various forms of osteoporosis (senile, immobility), osteomalacia and osteitis fibrosa cystica

Koopmotieven de Grachten, Uitwellingerga:onderzoeksrapport

SDDM-research heeft onderzoek gedaan naar de koopmotieven van de bewoners uit project ‘De Grachten’ te Uitwellingerga. Wat waren de beweegredenen voor de bewoners om specifiek dit project te kiezen en wat maakt dit project nu zo speciaal? Door middel van gedegen onderzoek is het gelukt de koopmotieven van de bewoners duidelijk in kaart te brengen. Studentenonderzoek in het kader van het thema Werklandschappe

Puzzled by GRB 060218

We study the optical-UV/X-ray spectral energy distribution of GRB 060218 during the prompt phase and during what seems to be the afterglow phase. The results are puzzling, since if the opt-UV and the X-ray emission belong to a single backbody (BB), then its luminosity is too large, and this BB cannot be interpreted as the signature of the shock breakout of the supernova. There are also serious problems in associating the emission expected by the supernova shock breakout with either the opt-UV or the X-ray emission. In the former case we derive too small ejecta velocities; in the latter case, on the contrary, the required velocity is too large, corresponding to the large radius of a BB required to peak close to the UV band. We then present what we think is the most conservative alternative explanation, namely a synchrotron spectrum, self-absorbed in the opt-UV and extending up to the X-ray band, where we observe the emission of the most energetic electrons, which are responsible for the exponential roll-over of the spectrum. The obtained fit can explain the entire spectrum except the BB observed in the X-rays, which must be a separate component. The puzzling feature of this interpretation is that the same model is required to explain the spectrum also at later times, up to 1e5 s, because the opt-UV emission remains constant in shape and also (approximately) in normalisation. In this case the observed X-ray flux is produced by self-Compton emission. Thus the prompt emission phase should last for ~1e5 s or more. Finally, we show that the BB observed in X-rays, up to 7000 seconds, can be photospheric emission from the cocoon or stellar material, energized by the GRB jet at radii comparable to the stellar radius (i.e. 1e10-1e11 cm), not very far from where this material becomes transparent (e.g. 1e12 cm).Comment: revised version accepted for publication in MNRAS (Letters

Differences in presentation between paediatric- and adult-onset primary Sjögren's syndrome patients

OBJECTIVES: Primary Sjögren's syndrome (pSS) is a rare disease in paediatric patients. Presenting symptoms differ from those in adult patients. The aim of this study was to evaluate presenting symptoms, classification criteria and clinical assessments, including salivary gland ultrasonography (SGUS), at disease onset in paediatric and adult patients with pSS. METHODS: Data of 23 paediatric- and 33 adult-onset patients with pSS were obtained from our standardised multidisciplinary REpSULT and RESULT cohorts, respectively. Clinical, patient-reported, serological, functional, biopsy and SGUS parameters were compared. RESULTS: In paediatric-onset pSS (pedSS) patients, recurrent parotid gland swelling (91% vs. 49%, p<0.001) and fever (30% vs. 3%, p=0.006) were more often present than in adult-onset patients. In contrast, sicca symptoms of mouth (52% vs. 79%, p=0.046) and eyes (26% vs. 73%, p<0.001) were less common in pedSS patients. In paediatric patients, the entry criteria of the ACR/EULAR classification were most often met due to activity in the glandular domain of the ESSDAI. When applying the ACR/EULAR classification criteria, only 78% of pedSS fulfilled these criteria compared to 100% of adult patients. Abnormal glandular function tests had a greater contribution to fulfilling the criteria in adults, while the biopsy had a greater contribution in paediatric patients. Anti-SSA/Ro serology had similar contribution for both cohorts. SGUS Hocevar score was significantly higher in paediatric compared to adult patients (median 25 vs. 18, p=0.004). CONCLUSION: PedSS has a different presentation than adult-onset pSS. Recurrent parotid gland swelling in paediatric patients should alert clinicians to the potential presence of pSS