Could a vitamin D deficiency cause a combined long-term FEV1 and bone mineral density deterioration in female asthmatics?

OBJECTIVES: We already know that asthma is associated to osteoporosis/osteopenia and characterized by an accelerated lung function decline. Our study aimed at assessing whether lung function decline and bone mineral density (BMD) deterioration in time were associated in a group of female long-standing asthmatics. We also tried to understand whether these two aspects were related to ICS treatment and vitamin D levels. METHODS: 35 female asthmatics were retrospectively analysed. Results of methacholine challenge test at asthma onset, FEV1%, bone density scan at moment of recruitment and after at least 5years later were considered. RESULTS: A significant positive relationship between femoral-t-scores changes and FEV1 decline was found after a median follow-up time of 7 [6-9] years (r=0.43;p=0.04). Femoral-t-score variations and vitamin D values were also significantly related (r=0.669;p=0.024). Furthermore, we found that FEV1 decline was worse in subjects with lower vitamin D levels (-57.5[-80.4-35.9]ml/year), compared to those with normal vitamin D rates (12[-16-23.6]ml/year;p=0.055). Femoral/vertebral t-score changes, as well as FEV1, decline were not associated to the use of medium/high ICS doses when compared to subjects treated with low ICS dosages. CONCLUSIONS: FEV ¹ decline and BMD deterioration in time observed in a group of female asthmatics were associated; low vitamin D levels may be the link.

Well-balanced compressible cut-cell simulation of atmospheric flow.

Cut-cell meshes present an attractive alternative to terrain-following coordinates for the representation of topography within atmospheric flow simulations, particularly in regions of steep topographic gradients. In this paper, we present an explicit two-dimensional method for the numerical solution on such meshes of atmospheric flow equations including gravitational sources. This method is fully conservative and allows for time steps determined by the regular grid spacing, avoiding potential stability issues due to arbitrarily small boundary cells. We believe that the scheme is unique in that it is developed within a dimensionally split framework, in which each coordinate direction in the flow is solved independently at each time step. Other notable features of the scheme are: (i) its conceptual and practical simplicity, (ii) its flexibility with regard to the one-dimensional flux approximation scheme employed, and (iii) the well-balancing of the gravitational sources allowing for stable simulation of near-hydrostatic flows. The presented method is applied to a selection of test problems including buoyant bubble rise interacting with geometry and lee-wave generation due to topography.

Analysis of macrophage migration inhibitory factor (MIF) in patients with idiopathic pulmonary fibrosis.

By proteomic approach we previously characterised bronchoalveolar lavage (BAL) protein profiles of patients with idiopathic pulmonary fibrosis (IPF), sarcoidosis and systemic sclerosis. Among differently expressed proteins we identified macrophage migration inhibitory factor (MIF), a multi-function pleiotropic cytokine. This study was performed to validate our findings by a further proteomic approach and ELISA in a larger population of patients and controls. MIF expression in lung tissue was also evaluated by immunohistochemistry. MIF was identified in all 2-DE gels of IPF patients and it was significantly increased compared to controls (p<0.05). This result was confirmed by ELISA: MIF concentrations were significantly higher in IPF patients than controls (p<0.001) and were directly correlated with neutrophil percentages (p=0.0095). Immunohistochemical analysis revealed enhanced expression in bronchiolar epithelium, alveolar epithelium, and fibroblastic foci. In conclusion, MIF is a pleiotropic cytokine that could be involved in the pathogenesis of IPF, being particularly abundant in BAL of these patients and mainly expressed in the areas of active fibrosis.

Bone ultrasonography in glucocorticoid-induced osteoporosis.

Osteoporosis is one of the major complications of glucocorticoid (GC) therapy. Few data are available on the usefulness of quantitative ultrasound (QUS), a technique that could also theoretically provide information on bone structure, in the management of glucocorticoid-induced osteoporosis (GIO). This study aimed (1) to evaluate the ability of QUS in detecting bone impairment and in being associated with the prevalence of fragility fracture in GC patients; and (2) to assess whether QUS parameters, and particularly the graphic trace analysis of QUS signal at phalanges, show any peculiar pattern of GIO. We studied 192 patients (136 women and 56 men, mean age 56.7 +/- 14.2 years) on treatment with GCs for at least 6 months, and 192 sex- and age-matched controls. In all subjects, we measured bone mineral density (BMD) at lumbar spine and at femur by DXA, and ultrasound parameters at calcaneus and phalanges. All DXA and QUS parameters were significantly lower in GC patients than in controls and in fracture than in nonfracture GC patients. BMD at lumbar spine showed the best ability in discriminating GC patients with or without fractures. Among QUS parameters, stiffness showed a discriminatory ability significantly better than AD-SoS. BMD at lumbar spine and total femur, stiffness, and AD-SoS are able to predict the odds of fragility fracture event. QUS parameters of the postmenopausal GC patients (n = 105) and of the postmenopausal healthy controls (n = 101) were also compared with those obtained in a separate sample of 90 postmenopausal osteoporotic women (PMO). All parameters were significantly lower in GC patients and in PMO than in controls, without any significant difference between GC and PMO. Our findings show that QUS can be useful in the assessment of glucocorticoid-induced bone impairment. In addition, in this study we found no alteration in QUS parameters or in the graphic trace analysis which could differentiate between GIO and PMO. Further longitudinal studies are needed to define the role of QUS in the prediction of fracture risk and in the clinical management of GIO.