2,006 research outputs found
Functional consequences of seven novel mutations in the CYP11B1 Gene: four mutations associated with nonclassic and three mutations causing classic 11 -Hydroxylase Deficiency
Context: Steroid 11β-hydroxylase (CYP11B1) deficiency (11OHD) is the second most common form of congenital adrenal hyperplasia (CAH). Cases of nonclassic 11OHD are rare compared with the incidence of nonclassic 21-hydroxylase deficiency.
Objective: The aim of the study was to analyze the functional consequences of seven novel CYP11B1 mutations (p.M88I, p.W116G, p.P159L, p.A165D, p.K254_A259del, p.R366C, p.T401A) found in three patients with classic 11OHD, two patients with nonclassic 11OHD, and three heterozygous carriers for CYP11B1 mutations.
Methods: We conducted functional studies employing a COS7 cell in vitro expression system comparing wild-type (WT) and mutant CYP11B1 activity. Mutants were examined in a computational three-dimensional model of the CYP11B1 protein.
Results: All mutations (p.W116G, p.A165D, p.K254_A259del) found in patients with classic 11OHD have absent or very little 11β-hydroxylase activity relative to WT. The mutations detected in patients with nonclassic 11OHD showed partial functional impairment, with one patient being homozygous (p.P159L; 25% of WT) and the other patient compound heterozygous for a novel mild p.M88I (40% of WT) and the known severe p.R383Q mutation. The two mutations detected in heterozygous carriers (p.R366C, p.T401A) also reduced CYP11B1 activity by 23 to 37%, respectively.
Conclusion: Functional analysis results allow for the classification of novel CYP11B1 mutations as causative for classic and nonclassic 11OHD, respectively. Four partially inactivating mutations are predicted to result in nonclassic 11OHD. These findings double the number of mild CYP11B1 mutations previously described as associated with mild 11OHD. Our data are important to predict phenotypic expression and provide important information for clinical and genetic counseling i
Misuse and Artifact in Factor Analytic Research
The theory of factor analysis has been developed for incorporating mathematical statistical theories such as the maximum likelihood method and asymptotic methods. However, there have been several instances of misuse while employing procedures for factor analysis studies. In several studies, factor analysis has been performed by deleting items exhibiting the ceiling effect or floor effect. The number of samples required for factor analysis is not well known. Kaiser-Guttman criterion cannot be applied for determining the number of factors. Furthermore, various studies have employed Scree Graphs and Parallel Analysis for the said purpose, but no definitive method exists for the same. Orthogonal rotation methods such as Varimax cannot be considered as a conclusive solution. However, Geomin has been considered as a better rotation method not only for simple structure but also for more complex factor configuration. Simple structure and bifactor structure are discussed in connection to factor rotation problem. Although there are various artifacts associated with the usage of factor analysis, this issue can be addressed by verifying factorial invariance through multi-group simultaneous analysis incorporated by SEM programs such as Mplus and R Package.因子分析の理論は、最尤法と漸近的方法のような数理統計学的理論を組み込んだ形で発展してきた。しかしながら、因子分析研究の手順にはまだ誤用がみられる。いくつかの研究において、天井効果や床効果を示す項目を削除して因子分析が行われている。因子分析に必要なサンプル数は明確ではない。因子の数を決定するためにKaiser-Guttman 基準は使うことはできない。そして、この目的でScree Graph とParallel Analysis を使用している研究は数多くあるが、そのための決定的な方法はない。Varimax のような直交回転は最終的な解と考えることはできない。しかしながら、Geomin は単純構造だけでなくより複雑な因子の布置に対しても優れた回転方法と考えられている。因子回転問題を考慮した単純構造とbifactor 構造について議論した。因子分析の使い方には多くのartifacts があるが、この問題は、Mplus やR Package などのSEMプログラムによって組み込まれた複数集団の同時分析によって因子的不変性を検証することによって対処することができる
Measurement of the ground-state flux diagram of three coupled qubits as a first step towards the demonstration of adiabatic quantum computation
The ground state susceptibility of a system consisting of three flux-qubits
was measured in the complete three dimensional flux space around the common
degeneracy point of the qubits. The system's Hamiltonian could be completely
reconstructed from measurements made far away from the common degeneracy point.
The subsequent measurements made around this point show complete agreement with
the theoretical predictions which follow from this Hamiltonian. The ground
state anti-crossings of the system could be read-out directly from these
measurements. This allows one to determine the ground-state flux diagram, which
provides the solution for the non-polynomial optimization problem MAXCUT
encoded in the Hamiltonian of the three-flux-qubit system. Our results show
that adiabatic quantum computation can be demonstrated with this system
provided that the energy gap and/or the speed of the read-out is increased.Comment: accepted for publication by Europhysics Letter
Challenging Perceptions of Disability through Performance Poetry Methods: The "Seen but Seldom Heard" Project.
This paper considers performance poetry as a method to explore lived experiences
of disability. We discuss how poetic inquiry used within a participatory arts-based
research framework can enable young people to collectively question society’s
attitudes and actions towards disability. Poetry will be considered as a means to
develop a more accessible and effective arena in which young people with direct
experience of disability can be empowered to develop new skills that enable them
to tell their own stories. Discussion of how this can challenge audiences to critically reflect upon their own perceptions of disability will also be developed
Sources of pro-cyclicality in east Asian financial systems
Procyclicality is a normal feature of economic systems, but financial sector
weaknesses can exacerbate it sufficiently to pose a threat to macroeconomic and financial
stability. These include shortcomings in bank risk management and governance, in
supervision and in terms of dependence on volatile sources of funds. The paper tests
econometrically for the importance of such features leading to pro-cyclicality in the financial
systems of 11 East Asian countries. This analysis makes it possible to identify specific policy
measures for East Asian countries that could limit the extent to which financial systems
exacerbate pro-cyclicality
Pseudogap behavior of nuclear spin relaxation in high Tc superconductors in terms of phase separation
We analyze anew experiments on the NMR in cuprates and find an important
information on their phase separation and its stripe character hidden in the
dependence of on degree of doping. In a broad class of materials
is the sum of two terms: the temperature independent one
attributed to ``incommensurate'' stripes that occur at external doping, and an
``universal'' temperature dependent term ascribed to moving metallic and AF
sub-phases. We argue that the frustrated first order phase transition in a
broad temperature interval bears a dynamical character.Comment: 5 pages, 3 figures; some comments and references added; accepted for
publication in JETP Letter
Differences in efficacy of monepantel, derquantel and abamectin against multi-resistant nematodes of sheep
Drug resistance has become a global phenomenon in gastrointestinal nematodes of sheep, particularly resistance to macrocyclic lactones. New anthelmintics are urgently needed for both the control of infections with multi-resistant nematodes in areas where classical anthelmintics are no longer effective, and the prevention of the spread of resistance in areas where the problem is not as severe. Recently, two new active ingredients became commercially available for the treatment of nematode infections in sheep, monepantel (Zolvix®) and derquantel, the latter used only in a formulated combination with the macrocyclic lactone, abamectin (Startect®). In order to assess the potential of the new actives for the control and prevention of spread of anthelmintic resistance, two characterized multi-resistant field isolates from Australia were used in a GLP (good laboratory practice) conducted efficacy study in sheep. Eight infected sheep in each group were treated orally according to the product labels with 2.5 mg/kg body weight monepantel, 0.2 mg/kg abamectin, or with the combination of 2.0 mg/kg derquantel and 0.2 mg/kg abamectin. The results demonstrate that monepantel was fully effective against multi-resistant species, Trichostrongylus colubriformis and Haemonchus contortus (99.9%). In contrast, the combination of derquantel and abamectin was effective against T. colubriformis (99.9%), but was not effective against larval stages of the barber's pole worm H. contortus (18.3%)
Effective Lorentz Force due to Small-angle Impurity Scattering: Magnetotransport in High-Tc Superconductors
We show that a scattering rate which varies with angle around the Fermi
surface has the same effect as a periodic Lorentz force on magnetotransport
coefficients. This effect, together with the marginal Fermi liquid inelastic
scattering rate gives a quantitative explanation of the temperature dependence
and the magnitude of the observed Hall effect and magnetoresistance with just
the measured zero-field resistivity as input.Comment: 4 pages, latex, one epsf figure included in text. Several revisions
and corrections are included. Major conclusions are the sam
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