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Bariatric surgery in an obese patient with Albright hereditary osteodystrophy: a case report
INTRODUCTION: We report for the first time the case of a patient with Albright hereditary osteodystrophy and pseudopseudohypoparathyroidism who underwent a Roux-en-Y gastric bypass.
CASE PRESENTATION: A 26-year-old obese Caucasian woman with Albright hereditary osteodystrophy with pseudopseudohypoparathyroidism (heterozygous mutation (L272F) in GNAS1 exon 10 on molecular analysis) was treated with gastric bypass. She had the classical features of Albright hereditary osteodystrophy: short stature (138cm), obesity (body mass index 49.5kg/m2), bilateral shortening of the fourth and fifth metacarpals, short neck, round and wide face with bombed front and small eyes. Before the gastric bypass was performed, biochemical determination revealed a slightly low serum calcium level (2.09mmol/L; normal range 2.1 to 2.5mmol/l), and an elevated parathyroid hormone level (87ng/L; normal range 10 to 70ng/L) associated with low vitamin D level (19μg/L; normal range 30 to 50μg/L). Vitamin D supplementation was prescribed before surgery. After the Roux-en-Y gastric bypass, she achieved a progressive substantial weight loss, from 94kg (body mass index 49.5kg/m2) to 49kg (body mass index 25.9kg/m2) in one year. Her weight then stabilized at 50kg (body mass index 26kg/m2) during our three years of follow-up. Before the operation and every three months after it, she was screened for nutritional deficiencies, and serum markers of bone turnover and renal function were monitored. Considering the deficiencies in zinc, magnesium, calcium, vitamin D and vitamin B12, appropriate supplementation was prescribed. Before and two years after the Roux-en-Y gastric bypass, a dual-energy X-ray absorptiometry assessment of bone density was performed that showed no changes on her lumbar column (0.882g/cm2 and both T-score and Z-score of -1.5 standard deviation). In addition, bone microarchitecture with a measurement of her trabecular bone score was found to be normal.
CONCLUSION: This is the first case of Roux-en-Y gastric bypass described in a patient with pseudopseudohypoparathyroidism showing that such a procedure seems to be safe in obese patients with Albright hereditary osteodystrophy and pseudopseudohypoparathyroidism if appropriately followed up. As obesity is a prominent feature of Albright hereditary osteodystrophy, such patients might seek bariatric surgery. After a Roux-en-Y gastric bypass, patients with Albright hereditary osteodystrophy associated with pseudopseudohypoparathyroidism need long-term follow-up on nutritional and metabolic issues
Measurement of the Cotton Mouton effect of water vapour
In this paper we report on a measurement of the Cotton Mouton effect of water
vapour. Measurement performed at room temperature ( K) with a wavelength
of 1064 nm gave the value for the
unit magnetic birefringence (1 T magnetic field and atmospheric pressure)
New PVLAS model independent limit for the axion coupling to for axion masses above 1meV
During 2014 the PVLAS experiment has started data taking with a new apparatus
installed at the INFN Section of Ferrara, Italy. The main target of the
experiment is the observation of magnetic birefringence of vacuum. According to
QED, the ellipticity generated by the magnetic birefringence of vacuum in the
experimental apparatus is expected to be . No ellipticity signal is present so far with a noise floor
after 210 hours of data taking.
The resulting ellipticity limit provides the best model independent upper limit
on the coupling of axions to for axion masses above eV
Measurements of vacuum magnetic birefringence using permanent dipole magnets: the PVLAS experiment
The PVLAS collaboration is presently assembling a new apparatus (at the INFN
section of Ferrara, Italy) to detect vacuum magnetic birefringence (VMB). VMB
is related to the structure of the QED vacuum and is predicted by the
Euler-Heisenberg-Weisskopf effective Lagrangian. It can be detected by
measuring the ellipticity acquired by a linearly polarised light beam
propagating through a strong magnetic field. Using the very same optical
technique it is also possible to search for hypothetical low-mass particles
interacting with two photons, such as axion-like (ALP) or millicharged
particles (MCP). Here we report results of a scaled-down test setup and
describe the new PVLAS apparatus. This latter one is in construction and is
based on a high-sensitivity ellipsometer with a high-finesse Fabry-Perot cavity
() and two 0.8 m long 2.5 T rotating permanent dipole magnets.
Measurements with the test setup have improved by a factor 2 the previous upper
bound on the parameter , which determines the strength of the nonlinear
terms in the QED Lagrangian: T
95% c.l. Furthermore, new laboratory limits have been put on the inverse
coupling constant of ALPs to two photons and confirmation of previous limits on
the fractional charge of millicharged particles is given
First results from the new PVLAS apparatus: a new limit on vacuum magnetic birefringence
Several groups are carrying out experiments to observe and measure vacuum
magnetic birefringence, predicted by Quantum Electrodynamics (QED). We have
started running the new PVLAS apparatus installed in Ferrara, Italy, and have
measured a noise floor value for the unitary field magnetic birefringence of
vacuum T (the error
represents a 1 deviation). This measurement is compatible with zero and
hence represents a new limit on vacuum magnetic birefringence deriving from non
linear electrodynamics. This result reduces to a factor 50 the gap to be
overcome to measure for the first time the value of predicted by QED:
~T. These birefringence measurements also yield improved
model-independent bounds on the coupling constant of axion-like particles to
two photons, for masses greater than 1 meV, along with a factor two improvement
of the fractional charge limit on millicharged particles (fermions and
scalars), including neutrinos
Impaired GH Secretion in Patients with SHOX Deficiency and Efficacy of Recombinant Human GH Therapy.
Background/Aims: Mutations of the short stature homeobox-containing (SHOX) gene on the pseudoautosomal region of the sex chromosomes cause short stature. GH treatment has been recently proposed to improve height in short patients with SHOX deficiency. The aim of this study was to evaluate GH secretion and analyze growth and safety of recombinant human GH (rhGH) therapy in short children and adolescents with SHOX deficiency. Patients and Design: We studied 16 patients (10 females; 9.7 ± 2.9 years old; height -2.46 ± 0.82 standard deviation score, SDS) with SHOX deficiency. All subjects underwent auxological evaluations, biochemical investigations, and were treated with rhGH (0.273 ± 0.053 mg/kg/week). Results: Impaired GH secretion was present in 37.5% of the studied subjects. Comparing baseline data with those at the last visit, we found that rhGH treatment improved growth velocity SDS (from -1.03 ± 1.44 to 2.77 ± 1.95; p = 0.001), height SDS (from -2.41 ± 0.71 to -1.81 ± 0.87; p < 0.001), and IGF-1 values (from -0.57 ± 1.23 to 0.63 ± 1.63 SDS, p = 0.010) without affecting body mass index SDS. Height SDS measured at the last visit was significantly correlated with chronological age (r = -0.618, p = 0.032), bone age (r = -0.582, p = 0.047) and height SDS (r = 0.938, p < 0.001) at the beginning of treatment. No adverse events were reported on rhGH therapy which was never discontinued. Conclusion: These data showed that impaired GH secretion is not uncommon in SHOX deficiency subjects, and that rhGH therapy may be effective in increasing height in most of these patients independent of their GH secretory status, without causing any adverse events of concern
Probing the dynamics of quasicrystal growth using synchrotron live imaging
The dynamics of quasicrystal growth remains an unsolved problem in condensed
matter. By means of synchrotron live imaging, facetted growth proceeding by the
tangential motion of ledges at the solid-melt interface is clearly evidenced
all along the solidification of icosahedral AlPdMn quasicrystals. The effect of
interface kinetics is significant so that nucleation and free growth of new
facetted grains occur in the melt when the solidification rate is increased.
The evolution of these grains is explained in details, which reveals the
crucial role of aluminum rejection, both in the poisoning of grain growth and
driving fluid flow
Metric gravity theories and cosmology:II. Stability of a ground state in f(R) theories
A fundamental criterion of viability of any gravity theory is existence of a
stable ground-state solution being either Minkowski, dS or AdS space. Stability
of the ground state is independent of which frame is physical. In general, a
given theory has multiple ground states and splits into independent physical
sectors. All metric gravity theories with the Lagrangian being a function of
Ricci tensor are dynamically equivalent to Einstein gravity with a source and
this allows us to study the stability problem using methods developed in GR. We
apply these methods to f(R) theories. As is shown in 13 cases of Lagrangians
the stability criterion works simply and effectively whenever the curvature of
the ground state is determined. An infinite number of gravity theories have a
stable ground state and further viability criteria are necessary.Comment: A modified and expanded version of a second part of the paper which
previously appeared as gr-qc/0702097v1. The first, modified part is now
published as gr-qc/0702097v2 and as a separate paper in Class. Qu. Grav. The
present paper matches the published versio
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