29 research outputs found
Monitoring serum insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), IGF-I/IGFBP-3 molar ratio and leptin during growth hormone treatment for disordered growth
OBJECTIVE: Serum IGF-I levels are monitored during
GH replacement treatment in adults with GH defi-
ciency (GHD) to guide GH dose adjustment and to
minimize occurrence of GH-related side-effects. This
is not routine practice in children treated with GH. The
aim of this study was to evaluate changes in (1) serum
IGF-I, IGFBP-3 and IGF-I/IGFBP-3 molar ratio, and (2)
serum leptin, an indirect marker of GH response,
during the first year of GH treatment in children with
disordered growth.
DESIGN: An observational prospective longitudinal
study with serial measurements at five time points
during the first year of GH treatment was carried out.
Each patient served as his/her own control.
PATIENTS The study included 31 patients, grouped
as (1) GHD (n=20) and (2) non-GHD (Turner syndrome
n=7; Noonan syndrome n=4), who had not previously
received GH treatment.
MEASUREMENTS: Serum IGF-I, IGFBP-3 and leptin
levels were measured before treatment and after
6 weeks, 3 months, 6 months and 12 months of GH
treatment, with a mean dose of 0.5 IU/kg/wk in GHD
and 0.7 IU/kg/wk in non-GHD groups. IGF-I, IGFBP-3
and the calculated IGF-I/IGFBP-3 molar ratio were
expressed as SD scores using reference values from
the local population.
RESULTS: In the GHD group, IGF-I SDS before treatment was lower compared with the non-GHD (-5.4 ± 2.5 vs. -1.8 ± 1.0; P < 0.001). IGF-I (-1.8 SDS ± 2.2) and IGFBP-3 (-1.1 SDS ± 0.6) levels and their molar ratios were highest at 6 weeks and remained relatively constant thereafter. In the non-GHD group, IGF-I levels increased throughout the year and were maximum at 12 months (0.3 SDS ± 1.4) while IGFBP-3 (1.1 SDS ± 0.9) and IGF-I/IGFBP-3 molar ratio peaked at 6 months. In both groups, IGF-I SDS and IGF-I/IGFBP-3 during treatment correlated with the dose of GH expressed as IU/m2/week (r-values 0.77 to 0.89; P = 0.005) but not as IU/kg/week. Serum leptin levels decreased significantly during GH treatment in the GHD (median before treatment 4.0 g/l; median after 12 months treatment 2.4 g/l; P = 0.02) but not the non-GHD (median before treatment 3.0 g/l; median after 12 months treatment 2.6 g/l). In the GHD group, serum leptin before treatment correlated with 12 month change in height SDS (r = 0.70, P = 0.02).
CONCLUSIONS: The pattern of IGF-I, IGFBP-3 and
their molar ratio during the first year of GH treatment
differed between the GHD and non-GHD groups. Calculation
of GH dose by surface area may be preferable
to calculating by body weight. As a GH dose-dependent
increase in serum IGF-I and IGF-I/IGFBP-3 may
be associated with adverse effects, serum IGF-I and
IGFBP-3 should be monitored routinely during longterm
GH treatment. Serum leptin was the only variable
that correlated with first year growth response in
GHD
Field Measurements of Terrestrial and Martian Dust Devils
Surface-based measurements of terrestrial and martian dust devils/convective vortices provided from mobile and stationary platforms are discussed. Imaging of terrestrial dust devils has quantified their rotational and vertical wind speeds, translation speeds, dimensions, dust load, and frequency of occurrence. Imaging of martian dust devils has provided translation speeds and constraints on dimensions, but only limited constraints on vertical motion within a vortex. The longer mission durations on Mars afforded by long operating robotic landers and rovers have provided statistical quantification of vortex occurrence (time-of-sol, and recently seasonal) that has until recently not been a primary outcome of more temporally limited terrestrial dust devil measurement campaigns. Terrestrial measurement campaigns have included a more extensive range of measured vortex parameters (pressure, wind, morphology, etc.) than have martian opportunities, with electric field and direct measure of dust abundance not yet obtained on Mars. No martian robotic mission has yet provided contemporaneous high frequency wind and pressure measurements. Comparison of measured terrestrial and martian dust devil characteristics suggests that martian dust devils are larger and possess faster maximum rotational wind speeds, that the absolute magnitude of the pressure deficit within a terrestrial dust devil is an order of magnitude greater than a martian dust devil, and that the time-of-day variation in vortex frequency is similar. Recent terrestrial investigations have demonstrated the presence of diagnostic dust devil signals within seismic and infrasound measurements; an upcoming Mars robotic mission will obtain similar measurement types
Design and construction of the MicroBooNE detector
This paper describes the design and construction of the MicroBooNE liquid
argon time projection chamber and associated systems. MicroBooNE is the first
phase of the Short Baseline Neutrino program, located at Fermilab, and will
utilize the capabilities of liquid argon detectors to examine a rich assortment
of physics topics. In this document details of design specifications, assembly
procedures, and acceptance tests are reported