Background: Low bone mineral density (BMD) is recognised in individuals with cystic fibrosis (CF) although the pathogenesis remains unclear. The aims of this study were to compare BMD over a broad ...continuum of Australian individuals with CF with healthy controls and to examine the relationship between BMD and clinical parameters including physical activity, nutrition, and vitamin D levels. Methods: BMD of the lumbar spine (LS), total body (TB), femoral neck (FN), cortical wrist (R33%), and distal wrist (RUD) was examined in 153 individuals with CF aged 5.3–55.8 years (84 males) and in 149 local controls aged 5.6–48.3 years (66 males) using dual energy x ray absorptiometry. Anthropometric variables, body cell mass, markers of disease severity, corticosteroid usage, measures of physical activity, dietary calcium and caloric intake and serum vitamin D were assessed and related to BMD. Results: Compared with controls, mean BMD was not significantly different in children aged 5–10 years with CF. Adolescents (females 11–18 years, males 11–20 years) had reduced TB and R33% BMD when adjusted for age, sex, and height (difference in BMD (g/cm2) adjusted means between control and CF: TB = 0.04 (95% CI 0.01 to 0.07); R33% = 0.03 (95% CI 0.01 to 0.06)). BMD was reduced at all sites except R33% in adults (difference in BMD (g/cm2) adjusted means between control and CF: TB = 0.05 (95% CI 0.02 to 0.09); LS = 0.08 (95% CI 0.03 to 0.14); FN = 0.09 (95% CI 0.03 to 0.15); RUD = 0.03 (95% CI 0.01 to 0.05)). In children/adolescents BMD was weakly associated with nutritional status and disease severity. Conclusions: BMD was normal in a well nourished group of prepubertal children with CF. A BMD deficit appears to evolve during adolescence and becomes more marked in adults. Individuals with CF should optimise nutrition, partake in physical activity, and maximise lung health in order to optimise BMD. Further longitudinal studies are required to understand the evolution of reduced BMD in young people and adults with CF.
Abnormalities in the growth plate may lead to short stature and skeletal deformity including Leri Weil syndrome, which has been shown to result from deletions or mutations in the SHOX gene, a ...homeobox gene located at the pseudoautosomal region of the X and Y chromosome. We studied the expression of SHOX protein, by immunohistochemistry, in human fetal and childhood growth plates and mRNA by in situ hybridization in childhood normal and Leri Weil growth plate. SHOX protein was found in reserve, proliferative, and hypertrophic zones of fetal growth plate from 12 wk to term and childhood control and Leri Weil growth plates. The pattern of immunostaining in the proliferative zone of childhood growth plate was patchy, with more intense uniform immunostaining in the hypertrophic zone. In situ hybridization studies of childhood growth plate demonstrated SHOX mRNA expression throughout the growth plate. No difference in the pattern of SHOX protein or mRNA expression was seen between the control and Leri Weil growth plate. These findings suggest that SHOX plays a role in chondrocyte function in the growth plate.
Searches are under way in Advanced LIGO and Virgo data for persistent gravitational waves from continuous sources, e.g. rapidly rotating galactic neutron stars, and stochastic sources, e.g. relic ...gravitational waves from the Big Bang or superposition of distant astrophysical events such as mergers of black holes or neutron stars. These searches can be degraded by the presence of narrow spectral artifacts (lines) due to instrumental or environmental disturbances. We describe a variety of methods used for finding, identifying and mitigating these artifacts, illustrated with particular examples. Results are provided in the form of lists of line artifacts that can safely be treated as non-astrophysical. Such lists are used to improve the efficiencies and sensitivities of continuous and stochastic gravitational wave searches by allowing vetoes of false outliers and permitting data cleaning.
Background: A study was undertaken to observe the gains in bone mass in children and adolescents with cystic fibrosis (CF) over 24 months and to examine the relationship between areal bone mineral ...density (aBMD) and associated clinical parameters including physical activity, nutrition, and 25-hydroxyvitamin D (25OHD). Methods: Areal BMD of the total body (TB), lumbar spine (LS), and total femoral neck (FNt) were repeatedly measured in 85 subjects aged 5–18 years with CF and 100 age and sex matched controls over 2 years. At each visit anthropometric variables, nutritional parameters, pubertal status, disease severity, physical activity, dietary calcium, caloric intake, and serum 25OHD were assessed and related to aBMD. Results: After adjusting for age, sex, and height Z-score, gains in LS aBMD in children (5–10 years) and TB and FNt aBMD in adolescents (11–18 years) with CF were significantly less than in controls. Lean tissue mass was significantly associated with TB and LS aBMD gains in children and adolescents and explained a significant proportion of the aBMD deficit observed. Lung function parameters were significantly associated with aBMD gains in adolescents with CF. Conclusions: Inadequate bone mass accrual during childhood and adolescence contributes to the low bone mass observed in adults with CF. Accounting for the height discrepancy which is frequently observed in those with CF, in addition to age and sex, is important when assessing low bone mass in children and adolescents with CF. To optimise an individual’s potential to acquire maximal bone mass, it is necessary to maximise nutritional status and limit the progression of chronic suppurative lung disease.
Hardware injections are simulated gravitational-wave signals added to the Laser Interferometer Gravitational-wave Observatory (LIGO). The detectors’ test masses are physically displaced by an ...actuator in order to simulate the effects of a gravitational wave. The simulated signal initiates a control-system response which mimics that of a true gravitational wave. This provides an end-to-end test of LIGO’s ability to observe gravitational waves. The gravitational-wave analyses used to detect and characterize signals are exercised with hardware injections. By looking for discrepancies between the injected and recovered signals, we are able to characterize the performance of analyses and the coupling of instrumental subsystems to the detectors’ output channels. This paper describes the hardware injection system and the recovery of injected signals representing binary black hole mergers, a stochastic gravitational wave background, spinning neutron stars, and sine-Gaussians.
...adequate carbohydrate should be provided (oral and intravenous), followed by oral agents such as diazoxide, chlorothiazide, and nifedipine. ...pancreatic surgery may be required if maximum medical ...treatment fails to control the hypoglycaemia.
Abnormalities of calcium and vitamin D metabolism in cystic fibrosis (CF) are well documented. We tested the hypothesis that alterations in calcium metabolism are related to vitamin D deficiency, and ...that bone resorption is increased relative to accretion in patients with CF. Calcitropic hormones, electrolytes, osteocalcin (OC) and bone alkaline phosphatase (BAP), (markers of bone mineralisation), urinary deoxypyridinoline total (t) Dpd, a marker of bone resorption and lumbar spine bone mineral density (LS BMD), expressed as a z-score, were measured in 149 (81 M) CF and 141 (61 M) control children aged 5.3-10.99 years, adolescents aged 11-17.99 years and adults aged 18-55.9 years. Data were analysed by multiple regression to adjust for age. In patients, FEV(1)% predicted and CRP (as disease severity markers), genotype and pancreatic status (PS) were recorded. The distribution of PTH differed between groups ( P<0.0001), with CF levels both below and above the control range. 25OH vitamin D (25OHD) was not different in control and CF subjects ( P=0.06). Active hormonal vitamin D (1,25(OH)(2)D) was lower in the CF group ( P<0.0001), not explained by 25OHD or disease severity, as was serum magnesium ( P<0.0001). OC was decreased in CF adults ( P=0.004), and tDpd increased in CF adolescents ( P=0.003) and adults ( P=0.03). The ratio of OC to tDpd (a measure of bone coupling) was similar in CF and control children, but decreased in CF adolescents ( P=0.04) and adults ( P=0.02), suggesting decreased overall bone accrual in CF adolescents and uncoupling of bone balance in adults. 1,25(OH)2D was weakly correlated with OC in CF children ( r=0.43, P=0.01), and with tDpd in CF and control adolescents ( r=0.33, P=0.05 and r=0.36, P=0.02, respectively); thus there was limited evidence of association of calcitropic hormones, which had an abnormal pattern in all age groups, with bone turnover. There was no association between calcitropic hormones or bone turnover markers and LS BMD z-score. Despite vitamin D sufficiency, abnormalities of calcium metabolism and bone turnover markers were still apparent and bone accretion was decreased relative to resorption in the CF adolescent and adult groups. These changes were not fully explained by disease severity or genotype, but are consistent with reports of decreased BMD and unique bone histomorphometry in older subjects with CF.
Objective: To describe the aetiology, clinical features and appropriate treatment for hepatic glycogenosis in poorly controlled type 1 diabetes.
Methods: A review of three adolescents with poor ...diabetes control, hepatomegaly and elevated serum liver transaminase concentrations.
Results: Symptoms included abdominal pain, anorexia, nausea and vomiting. All had tender hepatomegaly; two had splenomegaly. Liver biopsy was performed on two patients. Histology revealed hepatic glycogenosis in both; one also demonstrated macrovesicular steatosis. With improved glycaemic control, all three showed resolution of their symptoms, organomegaly and elevated serum liver transaminase concentrations.
Conclusions: Insulin‐reversible hepatic glycogenosis is the most common cause of hepatomegaly and raised serum liver transaminase concentrations in children and adolescents with type 1 diabetes. Having excluded other causes of hepatic dysfunction, a 4 week therapeutic trial of improved glycaemic control is recommended prior to more invasive investigations.
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