bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alternative antiretroviral monitoring strategies for HIV‐infected patients in east Africa: opportunities to save more lives?
Authors: Braithwaite R Scott , Nucifora Kimberly A , Yiannoutsos Constantin T , Musick Beverly , Kimaiyo Sylvester , Diero Lameck , Bacon Melanie C , Wools‐Kaloustian Kara 
Published: August 2011

BackgroundUpdated World Health Organization guidelines have amplified debate about how resource constraints should impact monitoring strategies for HIV‐infected persons on combination antiretroviral therapy (cART). We estimated the incremental benefit and cost effectiveness of alternative monitoring strategies for east Africans with known HIV infection.MethodsUsing a validated HIV computer simulation based on resource‐limited data (USAID and AMPATH) and circumstances (east Africa), we compared alternative monitoring strategies for HIV‐infected persons newly started on cART. We evaluated clinical, immunologic and virologic monitoring strategies, including combinations and conditional logic (e.g., only perform virologic testing if immunologic testing is positive). We calculated incremental cost‐effectiveness ratios (ICER) in units of cost per quality‐adjusted life year (QALY), using a societal perspective and a lifetime horizon. Costs were measured in 2008 US dollars, and costs and benefits were discounted at 3%. We compared the ICER of monitoring strategies with those of other resource‐constrained decisions, in particular earlier cART initiation (at CD4 counts of 350 cells/mm3rather than 200 cells/mm3).ResultsMonitoring strategies employing routine CD4 testing without virologic testing never maximized health benefits, regardless of budget or societal willingness to pay for additional health benefits. Monitoring strategies employing virologic testing conditional upon particular CD4 results delivered the most benefit at willingness‐to‐pay levels similar to the cost of earlier cART initiation (approximately $2600/QALY). Monitoring strategies employing routine virologic testing alone only maximized health benefits at willingness‐to‐pay levels (> $4400/QALY) that greatly exceeded the ICER of earlier cART initiation.ConclusionsCD4 testing alone never maximized health benefits regardless of resource limitations. Programmes routinely performing virologic testing but deferring cART initiation may increase health benefits by reallocating monitoring resources towards earlier cART initiation.
Soluble amyloid precursor protein: a novel proliferation factor of adult progenitor cells of ectodermal and mesodermal origin
Authors: Demars Michael P , Bartholomew Amelia , Strakova Zuzana , Lazarov Orly 
Published: August 2011

Abstract
Introduction
Soluble amyloid precursor protein α (sAPPα) is a proteolyte of APP cleavage by α-secretase. The significance of the cleavage and the physiological role of sAPPα are unknown. A crystal structure of a region of the amino terminal of sAPPα reveals a domain that is similar to cysteine-rich growth factors. While a previous study implicates sAPPα in the regulation of neural progenitor cell proliferation in the subventricular zone of adult mice, the ubiquitous expression of APP suggests that its role as a growth factor might be broader.

Methods
sAPPα and α-secretase activities were determined in neural progenitor cells (NPCs), mesenchymal stem cells (MSC) and human decidua parietalis placenta stem cells (hdPSC). Inhibition of α-secretase was achieved by treatment with the matrixmetalloproteinase inhibitor GM6001, and proliferation was determined using clonogenic and immunocytochemical analysis of cell-lineage markers. Recovery of proliferation was achieved by supplementing GM6001-treated cells with recombinant soluble APPα. Expression of APP and its cellular localization in the subventricular zone was determined by Western blot and immunohistochemical analyses of APP wild type and knockout tissue. Alterations in pERK and pAKT expression as a function of soluble APPα production and activity in NPCs were determined by Western blot analysis.

Results
Here we show that sAPPα is a proliferation factor of adult NPCs, MSCs and hdpPSC. Inhibition of α-secretase activity reduces proliferation of these stem cell populations in a dose-dependent manner. Stem cell proliferation can be recovered by the addition of sAPPα in a dose-dependent manner, but not of media depleted of sAPPα. Importantly, sAPPα operates independently of the prominent proliferation factors epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF), but in association with ERK signaling and MAP-kinase signaling pathways. Levels of sAPPα and putative α-secretase, ADAM10, are particularly high in the subventricular zone of adult mice, suggesting a role for sAPPα in regulation of NPCs in this microenvironment.

Conclusions
These results determine a physiological function for sAPPα and identify a new proliferation factor of progenitor cells of ectodermal and mesodermal origin. Further, our studies elucidate a potential pathway for sAPPα signaling through MAP kinase activation.
Association Between Vitamin D and Risk of Colorectal Cancer: A Systematic Review of Prospective Studies
Authors: Ma Yanlei , Zhang Peng , Wang Feng , Yang Jianjun , Liu Zhihua , Qin Huanlong 
Published: August 2011

PurposeTo conduct a systematic review of prospective studies assessing the association of vitamin D intake or blood levels of 25-hydroxyvitamin D [25(OH)D] with the risk of colorectal cancer using meta-analysis.MethodsRelevant studies were identified by a search of MEDLINE and EMBASE databases before October 2010 with no restrictions. We included prospective studies that reported relative risk (RR) estimates with 95% CIs for the association between vitamin D intake or blood 25(OH)D levels and the risk of colorectal, colon, or rectal cancer. Approximately 1,000,000 participants from several countries were included in this analysis.ResultsNine studies on vitamin D intake and nine studies on blood 25(OH)D levels were included in the meta-analysis. The pooled RRs of colorectal cancer for the highest versus lowest categories of vitamin D intake and blood 25(OH)D levels were 0.88 (95% CI, 0.80 to 0.96) and 0.67 (95% CI, 0.54 to 0.80), respectively. There was no heterogeneity among studies of vitamin D intake (P = .19) or among studies of blood 25(OH)D levels (P = .96). A 10 ng/mL increment in blood 25(OH)D level conferred an RR of 0.74 (95% CI, 0.63 to 0.89).ConclusionVitamin D intake and blood 25(OH)D levels were inversely associated with the risk of colorectal cancer in this meta-analysis.
Long-Term Risk of Colorectal Cancer After Negative Colonoscopy
Authors: Brenner Hermann , Chang-Claude Jenny , Seiler Christoph M. , Hoffmeister Michael 
Published: August 2011

Purpose Colonoscopy is thought to be a powerful and cost-effective tool to reduce colorectal cancer (CRC) incidence and mortality. Empirical evidence for overall and risk group–specific definition of screening intervals is sparse. We aimed to assess the risk of CRC according to time since negative colonoscopy, overall, and by sex, smoking, and family history of CRC, in a large population-based case-control study. Patients and Methods In all, 1,945 patients with CRC and 2,399 population controls were recruited in 22 hospitals and through population registers in the Rhine-Neckar region of Germany from 2003 to 2007. Data on history of colonoscopy and important covariates were obtained by personal interviews and from medical records. Results Compared with people who had never undergone colonoscopy, people with a previous negative colonoscopy had a strongly reduced risk of CRC. Adjusted odds ratios for time windows of 1 to 2, 3 to 4, 5 to 9, 10 to 19, and 20+ years after negative colonoscopy were 0.14 (95% CI, 0.10 to 0.20), 0.12 (95% CI, 0.08 to 0.19), 0.26 (95% CI, 0.18 to 0.39), 0.28 (95% CI, 0.17 to 0.45), and 0.40 (95% CI, 0.24 to 0.66), respectively. Low risks even beyond 10 years after negative colonoscopy were observed for both left- and right-sided CRC and in all risk groups assessed except current smokers, who had a risk similar to that of never smokers with no previous colonoscopy 10 or more years after a negative colonoscopy. Conclusion These results support suggestions that screening intervals for CRC screening by colonoscopy could be longer than the commonly recommended 10 years in most cases, perhaps even among men and people with a family history of CRC, but probably not among current smokers.
The antiepileptic drug valproic acid and other medium-chain fatty acids acutely reduce phosphoinositide levels independently of inositol in Dictyostelium
Authors: Chang Pishan , Orabi Benoit , Deranieh Rania M. , Dham Manik , Hoeller Oliver , Shimshoni Jakob A. , Yagen Boris , Bialer Meir , Greenberg Miriam L. , Walker Matthew C. , Williams Robin S. B. 
Published: August 2011

SUMMARY
Valproic acid (VPA) is the most widely prescribed epilepsy treatment worldwide, but its mechanism of action remains unclear. Our previous work identified a previously unknown effect of VPA in reducing phosphoinositide production in the simple model Dictyostelium followed by the transfer of data to a mammalian synaptic release model. In our current study, we show that the reduction in phosphoinositide [PtdInsP (also known as PIP) and PtdInsP2 (also known as PIP2)] production caused by VPA is acute and dose dependent, and that this effect occurs independently of phosphatidylinositol 3-kinase (PI3K) activity, inositol recycling and inositol synthesis. In characterising the structural requirements for this effect, we also identify a family of medium-chain fatty acids that show increased efficacy compared with VPA. Within the group of active compounds is a little-studied group previously associated with seizure control, and analysis of two of these compounds (nonanoic acid and 4-methyloctanoic acid) shows around a threefold enhanced potency compared with VPA for protection in an in vitro acute rat seizure model. Together, our data show that VPA and a newly identified group of medium-chain fatty acids reduce phosphoinositide levels independently of inositol regulation, and suggest the reinvestigation of these compounds as treatments for epilepsy.
Regulation of in vitro diagnostics (IVDs) for use in clinical diagnostic laboratories: towards the light or dark in clinical laboratory testing?
Authors: Favaloro Emmanuel J. , Plebani Mario , Lippi Giuseppe 
Published: August 2011

AbstractA revised framework for the regulation of in vitro diagnostic devices (IVDs) came into force in Australia on July 1, 2010 that aims to ‘ensure that public and personal health are adequately protected’, but which instead may lead to adverse outcomes in clinical diagnosis and management. The regulatory process aims to regulate all IVDs, including those used by clinical diagnostic laboratories, which are already subject to scrutiny as part of the current laboratory accreditation process. The IVD regulatory process initiated in Australia is similar to that used in Canada, but different to that currently operating in the USA and Europe. However, it is feasible that other countries will in time adopt a similar regulatory framework, given that many countries are involved in the development process. In this opinion paper, the regulatory process for IVDs across several geographies are outlined, as are some benefits and weaknesses of the new regulatory process now applied to Australia, as potentially planned for other regions of the world.
Synthesis of a 19-(O-carboxymethyl)oxime hapten of 7β-hydroxy-epiandrosterone
Authors: Ferroud Clotilde , Revial Gilbert , Ricco Christophe , Hennebert Olivier , Morfin Robert 
Published: August 2011

Abstract
In order to develop an immunoassay of 7β-hydroxy-epiandrosterone, a stereoselective synthesis of a specific hapten, 7β-hydroxy-19-oxo-androstan 19-(O-carboxymethyl)oxime (17), was performed. This synthesis was achieved in 16% overall yield starting from the well-known 3β-acetoxy-19-hydroxy-5-androsten-17-one (1). After coupling of the alkyl oxime moiety, an allylic oxidation of the C-7 carbon under mild conditions followed by two selective reductions established all the functionalities of the final compound 17.
Quadratic properties in group amalgams
Authors: Fine Benjamin , Rosenberger Aila , Rosenberger Gerhard 
Published: August 2011

Abstract
Lyndon in [Combinatorial Group Theory, Springer-Verlag, 1977] proved that in a free group F each solution set {x, y, z} of the quadratic equation x
2
y
2
z
2 = 1 generates a cyclic group. This theorem launched the whole theory of equations over free groups which led eventually to the solution of the Tarski conjectures. Since Lyndon's theorem can be phrased as a universal sentence, it is true in all fully residually free groups, if we replace cyclic by abelian. In the present paper we consider amalgams of groups which satisfy Lyndon's theorem. We prove that this property and several other related properties involving quadratic and quadratic-type equations are preserved under free products with malnormal amalgamated subgroups. The situation in HNN groups is more complicated.
Stabilizers of ℝ-trees with free isometric actions of FN
Authors: Kapovich Ilya , Lustig Martin 
Published: August 2011

Abstract
We prove that if T is an ℝ-tree with a minimal free isometric action of FN
, then the Out(FN
)-stabilizer of the projective class [T] is virtually cyclic.
For the special case where T = T
+(ϕ) is the forward limit tree of an atoroidal iwip element ϕ ∈ Out(FN
) this is a consequence of the results of Bestvina, Feighn and Handel [Geom. Funct. Anal. 7: 215–244, 1997], via very different methods.
We also derive a new proof of the Tits alternative for subgroups of Out(FN
) containing an iwip (not necessarily atoroidal): we prove that every such subgroup G ⩽ Out(FN
) is either virtually cyclic or contains a free subgroup of rank two. The general case of the Tits alternative for subgroups of Out(FN
) is due to Bestvina, Feighn and Handel.
On factorizations of finite groups with ℱ-hypercentral intersections of the factors
Authors: Guo Wenbin , Skiba Alexander N. 
Published: August 2011

Abstract
A chief factor H/K of a group G is called ℱ-central if [H/K](G/CG
(H/K)) ∈ ℱ. The product of all such normal subgroups of G, whose G-chief factors are ℱ-central in G, is called the ℱ-hypercentre of G and denoted by . The finite groups G with factorizations G = AB, where for some class of groups ℱ, are studied. Some known results about factorizations of groups are generalized.
A note on element centralizers in finite Coxeter groups
Authors: Konvalinka Matjaž , Pfeiffer Götz , Röver Claas E. 
Published: August 2011

Abstract
The normalizer NW
(WJ
) of a standard parabolic subgroup WJ
of a finite Coxeter group W splits over the parabolic subgroup with complement NJ
consisting of certain minimal length coset representatives of WJ
in W. In this note we show that (with the exception of a small number of cases arising from a situation in Coxeter groups of type Dn
) the centralizer CW
(w) of an element w ∈ W is in a similar way a semidirect product of the centralizer of w in a suitable small parabolic subgroup WJ
with complement isomorphic to the normalizer complement NJ
. Then we use this result to give a new short proof of Solomon's Character Formula and discuss its connection to MacMahon's master theorem.
Lattice-defined classes of finite groups with modular Sylow subgroups
Authors: Andreeva Siyka , Schmidt Roland , Toborg Imke 
Published: August 2011

Abstract
If L is a lattice, a group is called L-free if its subgroup lattice has no sublattice isomorphic to L. It is easy to see that for every sublattice L of L
10, the subgroup lattice of the dihedral group of order 8, the finite L-free groups form a lattice-defined class of groups with modular Sylow subgroups. In this paper we determine the structure of these groups for the two non-modular 8-element sublattices of L
10.
A case-free characterization of hyperbolic Coxeter systems
Authors: Edgar Tom 
Published: August 2011

Abstract
We provide a case-free characterization of hyperbolic Coxeter systems depending only on the Coxeter graph. Consequently, we uncover a case-free proof of the fact that every infinite, non-affine Coxeter system contains a standard parabolic subsystem that is a hyperbolic Coxeter system.
On the q-tensor square of a group
Authors: Bueno Ticianne P. , Rocco Noraí R. 
Published: August 2011

Abstract
We study the non-abelian tensor square modulo q of a group, where q is a non-negative integer, via an operator ν

q
in the class of groups. Structural properties and finiteness conditions of νq
(G) are investigated. We compute the non-abelian tensor square modulo q of cyclic groups and develop a theory for computing νq
(G) and some of its relevant sections for polycyclic groups G. This extends the existing theory from the case q = 0 to all non-negative integers q. Additionally, a table of examples is produced with the help of the GAP system.
Sulfate complexation of element 104, Rf, in H2SO4/HNO3mixed solution
Authors: Li Z. J. , Toyoshima A. , Asai M. , Tsukada K. , Sato T. K. , Sato N. , Kikuchi T. , Nagame Y. , Schädel M. , Pershina Valeria , Liang X. H. , et al.  
Published: August 2011

AbstractThe cation-exchange behavior of261Rf (T1/2= 78 s) produced in the248Cm(18O, 5n) reaction was studied on a “one-atom-at-a-time” scale in 0.15–0.69 M H2SO4/HNO3mixed solutions ([H+]=1.0 M) using an automated ion-exchange separation apparatus coupled with the detection system for alpha-spectroscopy (AIDA). It was found that adsorption probabilities ( decrease with an increase of [HSO4−], showing a successive formation of Rf sulfate complexes. Rf exhibits a weaker complex formation tendency compared to the lighter homologues Zr and Hf. This is in good agreement with theoretical predictions including relativistic effects.
Le taux de change réel d'équilibre : une introduction
Authors: Joly Hervé , Prigent Céline , Sobczak Nicolas 
Published: August 2011

Le taux de change réel d'équilibre : une introduction par Hervé Joly, Céline Prigent, Nicolas Sobczak
Cet article présente les deux principales théories du taux de change réel d'équilibre. La première approche repose sur un modèle d'équilibre général intertemporel à deux secteurs; elle définit le taux de change réel comme le prix relatif des biens échangeables par rapport aux biens non-échangeables. Elle est la plus achevée d'un point de vue théorique mais est complexe à mettre en oeuvre empiriquement. La seconde approche est plus "macro-économique". Le change réel y est défini comme un indicateur de compétitivité; son niveau d'équilibre permet d'atteindre l'équilibre externe tout en étant compatible avec l'équilibre interne. Le calcul empirique est plus aisé et s'appuie les mécanismes les plus robustes inscrits dans les modèles macro-économétriques. Ces deux approches présentent des points communs, en particulier une définition intertemporelle de l'équilibre extérieur. Elles paraissent par ailleurs largement complémentaires dans la mesure où elles se réfèrent implicitement à des horizons temporels différents.
Les modèles monétaires de taux de change : un examen empirique
Authors: Jondeau Éric 
Published: August 2011

Monetary Exchange Rate Models: A New Empirical Study by Éric Jondeau
This paper makes an empirical study of the two main monetary exchange rate models, which assume perfectly flexible or short-run prices. In view of the non-stationarity of exchange rates and their determinants, the testable specifications normally from these models should be interpreted as long-run relations and the tests carried out using a multivariate error correction The monetary models are therefore estimated for the yen-dollar and the deutschemark-dollar over the 1973-1994 period. The induce a virtually systematic rejection of the flexible-prices model and appear considerably more favourable to the rigid-prices model.
Dette publique et taux de change dans les pays du G7 sur les deux dernières décennies
Authors: Paraponaris Alain 
Published: August 2011

Dette publique et taux de change dans les pays du G7 sur les deux dernières décennies
par Alain Paraponaris
Les travaux empiriques sur le taux de change se divisent grossièrement en modèles univariés et modèles macro-économiques en économie ouverte. Les premiers n'ont aucun fondement particulier de théorie macro-économique mais présentent les meilleures performances prédictives dans le court terme. Les seconds donnent des prévisions de court terme moins bonnes, mais aident à la compréhension de l'évolution des taux de change à long terme. Ce papier présente rapidement quelques faits stylisés pour les pays du G7 en essayant de relier l'évolution récente des taux de change avec celle de la dette publique. L'étude empirique s'appuie sur des tests de cointégration, des tests de causalité au sein de modèles à correction d'erreur, des simulations de chocs sur variables et la décomposition de la variance d'erreurs de prévision. Elle permet de distinguer les pays où la relation causale va de la dette publique au taux de change (Canada, États-Unis) de ceux où la relation est inversée (Allemagne, France). La relation est bidirectionnelle pour la Grande-Bretagne et l'Italie, tandis que les résultats obtenus pour le Japon ne permettent pas de conclure.
La cohérence temporelle des anticipations de change : une étude sur données d'enquêtes
Authors: Benassy-Quéré Agnès , Raymond Hélène 
Published: August 2011

The Temporal Consistency of Exchange Rate Expectations: A Study Using Survey Data by Agnès Bénassy-Quéré and Hélène Raymond
The consistency of forecasts concerning different dates is a less stringent assumption than that of rational expectations, frequently rejected by survey data. However, temporal consistency tests are conditional on the forecast modeling adopted. The temporal consistency assumption is tested here for expectations relating to four exchange rates conditional on four forecast models. Three different surveys are processed and several models estimated to guarantee reasonably general results. Nevertheless, these results need to be made relative to the explanatory capacity of each model. The three-month exchange rate forecasts appear to comply with a naive model, while the longer run forecasts are more in line with a mixed extrapolative-adjustive-regressive model in which the regressive component is often preponderant. This variety of models used depending on the future time periods explains why the temporal consistency assumption is often rejected and, consequently, strengthens the assumption of irrational expectations.
Fragilité des systèmes de change fixe et contrôle des capitaux
Authors: Bensaïd Bernard , Jeanne Olivier 
Published: August 2011

Fragilité des systèmes de change fixe et contrôle des capitaux par Bernard Bensaïd et Olivier Jeanne
Nous étudions dans cet article la dynamique des crises de change sous les deux hypothèses suivantes. Premièrement, augmenter le taux d'intérêt nominal pour défendre la monnaie est coûteux, au delà d'un certain niveau, pour le gouvernement. Deuxièmement, le niveau de taux d'intérêt que le gouvernement est prêt à supporter avant de renoncer à défendre la monnaie n'est pas parfaitement connu par les acteurs du marché des changes. Nous montrons que sous ces conditions, des crises de change autoréalisatrices peuvent apparaître indépendamment des fondamentaux, et forcer le gouvernement à quitter le système de change fixe. Nous caractérisons ensuite les conditions sous lesquelles des contrôles des capitaux peuvent faire disparaître ce type d'instabilité.