bluuebunny/crossref_metadata_2025_split huggingface dataset:
No Evidence of Genetic Mediation in the Association Between Birthweight and Academic Performance in 2,413 Danish Adolescent Twin Pairs
Authors: Petersen Inge , Jensen Vibeke Myrup , McGue Matt , Bingley Paul , Christensen Kaare 
Published: November 2009

AbstractEvidence of a positive association between birthweight and IQ has been established in several studies. Analyses of within twin pair differences in birthweight and IQ have been used to shed light on the basis of the association. The strength of this approach is the possibility of controlling for both unmeasured common childhood–environmental factors as well as genetic factors shared by the co-twins. Two twin studies suggest the existence of genetic mediation between birthweight and IQ, that is, common genetic factors influence both fetal growth and IQ in childhood, while two other twin studies find no evidence of such mediation. In the present study we use a large population-based national register study of 2,413 Danish twin-pairs from birth cohorts 1986–1990, of which we have zygosity information on 74%. We perform individual level as well as intra-pair analyses of birthweight and school achievements at age 16. For both sexes we observed a monotonic increase in academic performance with increasing percentiles of birthweight. However, we did not find that this association is due to genetic mediation.
Unrelated ART Twins / Tribute: Dr Robert Derom / Twin Research Reviews: Transfusion Syndrome; Discordant MZ-Twin Method / Matched Talents: Tennis Twins: (Mike and Bob Bryan; Sonchai and Sonchat Ratiwatana); Television Twins: (Ellen and Lynda Kahn)
Authors: Segal Nancy L. 
Published: November 2009

AbstractAunique case of artificially conceived twins is described. The infants involved are unrelated to one another, as well as to the mother who carried them. The question of whether these individuals meet scientific criteria for being twins is considered, as is the issue of whether their parents are really parents of twins. Next, the International Society for Twin Studies acknowledges the life and work of its late esteemed colleague, Dr Robert Derom. His professional accomplishments on behalf of twins and twin research will be remembered, as will his helpfulness and generosity to fellow investigators. This tribute to Dr Derom is followed by reviews of new research on the pathophysiology of the twin transfusion syndrome and the use of discordant MZ twins (co-twin control) in behavioral research. The final section provides a review of the athletic talents of two sets of MZ twin tennis players, and the creative skills of a set of MZ twin designers.
Hypogonadism in females with Prader–Willi syndrome from infancy to adulthood: variable combinations of a primary gonadal defect and hypothalamic dysfunction
Authors: Eldar-Geva Talia , Hirsch Harry J , Benarroch Fortu , Rubinstein Orit , Gross-Tsur Varda 
Published: November 2009

ObjectiveThe variable hypogonadism in Prader–Willi syndrome (PWS) has generally been attributed to hypothalamic dysfunction. Recent studies have documented primary testicular dysfunction in PWS males. Our aims were to characterize sexual development and reproductive hormones in PWS females and to investigate the etiology of hypogonadism.DesignA cross-sectional study.MethodsPhysical examination was performed on 45 PWS females (aged 6 weeks to 32 years) and blood samples were obtained for hormonal analyses.ResultsAge of onset and progression of puberty varied; most adults had incomplete sexual development. Spontaneous menarche was reported in four (aged 15–30 years) but all had subsequently developed secondary amenorrhea or oligomennorrhea. Anti-Mullerian hormone levels were within the normal range in all age groups. Inhibin B was consistently low or undetectable; only five women had levels in the low-normal range (20–54 pg/ml). LH was normal in most children, but low (<1.0 IU/l) in 9 of 15 adults. FSH was within the normal range for age in most children, but low (<0.5 IU/l) in 10 and high in four adults. Estradiol levels were normal-low and androgen levels were normal in the majority.ConclusionsPubertal development in PWS females, as in males, is characterized by normal adrenarche, pubertal arrest, and hypogonadism due to variable combinations of a unique primary gonadal defect and hypothalamic dysfunction.
Influence of tungsten sources on the synthesis and properties of ammonium dioxothiotungstate
Authors: Bi Yunfei , Zeng Shuangqin , Li Dadong , Nie Hong 
Published: November 2009

AbstractAmmonium dioxothiotungstate was synthesized using different tungsten sources and characterized in detail by powder X-ray diffraction, energy dispersive X-ray spectrometry, transmission electron microscopy, nitrogen adsorption, and temperature-programmed sulfidation. It was found that tungsten oxide nanobelts are superior to ammonium metatungstate as tungsten source for the synthesis of ammonium dioxothiotungstate due to a time-consuming aging step being excluded from the synthesis route. Moreover, detailed characteristic data reveal that, when tungsten oxide nanobelts are used, the physical and chemical properties of the resulting ammonium dioxothiotungstate including particles size, specific surface area, and sulfidation pattern were improved. Also, the hydrodesulfurization measurements showed higher catalytic activity and balanced selectivity of the resulting ammonium dioxothiotungstate.
Restoration of erect posture by deep brain stimulation of the globus pallidus in disabling dystonic spinal hyperextension
Authors: Sakas Damianos E. , Stavrinou Lampis C. , Boviatsis Efstathios J. , Stathis Pantelis , Themistocleous Marios , Gatzonis Stylianos 
Published: November 2009

Dystonia is a movement disorder notoriously difficult to treat. While primary dystonia is classically considered to respond well to deep brain stimulation (DBS), treatment of secondary dystonia yields variable results. Patient selection should be done on a case-by-case basis. Clearly, there is a need to accumulate additional information with regard to prognostic factors that may aid neurosurgeons in selecting those patients in whom the disorder is most likely to respond favorably to pallidal DBS.
The authors report the case of a 29-year-old man with secondary dystonia due to perinatal hypoxia. The most prominent symptom was what we have termed ectatocormia—that is, severe, fixed truncal hyperextension and retrocollis, exacerbated by phasic, twisting movements of the trunk and head. This made it impossible for the patient to maintain a normal upright posture or to walk. The patient underwent bilateral DBS of the globus pallidus internus (GPi), and the authors observed impressive improvement in motor abilities and function. The patient's body adopted the normal upright posture and he became able to walk again, 4 months after the commencement of GPi stimulation.
This report, along with others, emphasizes that the GPi as an ideal target for alleviating axial tonic symptoms. The presence of normal MR imaging findings, a phenotypical purity of predominantly dystonic symptoms, and a younger age seem to favor a positive outcome.
The differential effects of pathway- versus target-derived glial cell line–derived neurotrophic factor on peripheral nerve regeneration
Authors: Magill Christina K. , Moore Amy M. , Yan Ying , Tong Alice Y. , MacEwan Matthew R. , Yee Andrew , Hayashi Ayato , Hunter Daniel A. , Ray Wilson Z. , Johnson Philip J. , Parsadanian Alexander , Myckatyn Terence M. , Mackinnon Susan E. 
Published: November 2009

Object
Glial cell line–derived neurotrophic factor (GDNF) has potent survival effects on central and peripheral nerve populations. The authors examined the differential effects of GDNF following either a sciatic nerve crush injury in mice that overexpressed GDNF in the central or peripheral nervous systems (glial fibrillary acidic protein [GFAP]–GDNF) or in the muscle target (Myo-GDNF).

Methods
Adult mice (GFAP-GDNF, Myo-GDNF, or wild-type [WT] animals) underwent sciatic nerve crush and were evaluated using histomorphometry and muscle force and power testing. Uninjured WT animals served as controls.

Results
In the sciatic nerve crush, the Myo-GDNF mice demonstrated a higher number of nerve fibers, fiber density, and nerve percentage (p < 0.05) at 2 weeks. The early regenerative response did not result in superlative functional recovery. At 3 weeks, GFAP-GDNF animals exhibit fewer nerve fibers, decreased fiber width, and decreased nerve percentage compared with WT and Myo-GDNF mice (p < 0.05). By 6 weeks, there were no significant differences between groups.

Conclusions
Peripheral delivery of GDNF resulted in earlier regeneration following sciatic nerve crush injuries than that with central GDNF delivery. Treatment with neurotrophic factors such as GDNF may offer new possibilities for the treatment of peripheral nerve injury.
Negative effect of hypopituitarism following brain trauma in patients with diffuse axonal injury
Authors: Jeong Jae Hyun , Kim Young Zoon , Cho Yong Woon , Kim Joon Soo 
Published: November 2009

Object
The aim of this prospective observational study was to assess the incidence and pattern of hypopituitarism after diffuse axonal injury (DAI) and to identify its effect on these patients in terms of functional outcome.

Methods
Of 1307 patients with traumatic brain injury treated at the authors' institution between March 2005 and June 2008, 65 patients with DAI were enrolled in the present study. The authors determined basal hormone levels, initial Glasgow Coma Scale scores, the Marshall CT grades, the presence of abnormal signal intensity indicating lesions on MR images, and duration of unconsciousness. At the 6-month follow-up visits, functional outcomes were estimated using the Modified Barthel Index. Univariate and multivariate analyses were performed to identify factors that influenced functional outcomes.

Results
Twenty-one patients with hypopituitarism (Group A) had more lesions in the body of the corpus callosum, basal ganglia, thalamus, and the gray–white matter junction than those without hypopituitarism (Group B). In Group A, growth hormone deficiency (17 patients, 80.9%) was the most common, and multiple pituitary hormone deficiencies were found in 12 patients (57.1%). The mean Modified Barthel Index score at the 6-month follow-up was 64.7 in Group A and 88.5 in Group B (p = 0.027). Duration of unconsciousness (p = 0.035), the Marshall CT grade (p = 0.021), hypopituitarism (p = 0.044), and abnormal signal intensities on MR imaging in midline or deep structures of the brain (p = 0.001) were found to be associated with functional outcome.

Conclusions
The findings in this prospective observational study suggest that hypopituitarism in patients with DAI has a relationship not only with injuries in the midline or deep structures of the brain, but also with a poor outcome.
Hepatitis B virus genotype B has an earlier emergence of lamivudine resistance than genotype C
Authors: Hsieh Ting-Hui , Tseng Tai-Chung , Liu Chun-Jen , Lai Ming-Yang , Chen Pei-Jer , Hsieh Hsin-Ling , Chen Ding-Shinn , Kao Jia-Horng 
Published: November 2009

Background Hepatitis B virus (HBV) genotype B and C seem not to affect the therapeutic response to lamivudine (3TC). Whether a given genotype has an earlier emergence of 3TC resistance remains unclear. We thus conducted this study to elucidate the association of HBV genotype with the emergence of 3TC-resistant strains in Taiwanese patients. Methods Forty chronic hepatitis B patients who developed resistance after 3TC therapy were retrospectively enrolled. HBV genotype, serum alanine aminotransferase (ALT) and HBV DNA levels were determined at baseline. The presence of 3TC-resistant mutations was confirmed by direct sequencing whenever biochemical breakthrough developed. Results The distribution of HBV genotype B and C in 40 patients receiving 3TC therapy were 60% and 40%, respectively. The mean interval to detect 3TC- resistant strain was 19.6 ±1.7 months. By using multivariate analysis, HBV genotype B and higher pre-treatment HBV DNA level were independently associated with earlier detection of 3TC-resistant strains. In addition, genotype B was significantly associated with development of 3TC resistance within the first 12 months of 3TC therapy compared with genotype C (odds ratio 8.27; P=0.004). Conclusions Compared with HBV genotype C, genotype B appears to have an earlier biochemical resistance to 3TC than genotype C. Therefore, more frequent monitoring of viral load or genotypical resistance might be needed for patients with HBV genotype B infection receiving 3TC therapy, especially during the first year.
Microstructure and Compression Strength of Novel TRIP‐Steel/Mg‐PSZ Composites
Authors: Biermann Horst , Martin Ulrich , Aneziris Christos G. , Kolbe Anja , Müller Angelika , Schärfl Wolfgang , Herrmann Mathias 
Published: November 2009

AbstractNovel composites on basis of austenitic stainless TRIP‐steel as matrix with reinforcements of Mg‐PSZ are presented. Compact rods were produced by cold isostatic pressing and sintering, square honeycomb samples by the ceramic extrusion technique. The samples are characterized by optical and scanning electron microscopy before and after deformation, showing the microstructure and the deformation‐ induced martensite formation. The mechanical properties of samples with 5 vol% zirconia are superior compared to zirconia‐free samples and composites with higher zirconia contents in terms of bending and compression tests. The honeycomb samples exhibit extraordinary high specific energy absorption in compression.
Two‐ and Three‐Dimensional Micro‐ and Sub‐Micrometer Periodic Structures Using Two‐Beam Laser Interference Lithography
Authors: Lasagni A. F. , Menéndez‐Ormaza B. S. 
Published: November 2009

AbstractIn this study, we present different approaches for the fabrication of two and three dimensional structures using two‐beam interference lithography. The advantages of using more than one irradiation step for the fabrication of complex structures are theoretically demonstrated by avoiding the introduction of line effects. For the fabrication of 3D structures, two alternatives are discussed including a layer by layer approach as well as a multidimensional (non‐orthogonal) interference exposure setup. Finally, an example of biomimetic patterning is given. In all cases, numerical calculations showed a good agreement with the experimental results, being able to explain the shape of the fabricated structures.
Synthesis and Characterization of Electrospun Mullite Nanofibers
Authors: Wu Jiang , Lin Hong , Li Jianbao , Zhan Xiaobo , Li Junfeng 
Published: November 2009

AbstractIn this study, continuous mullite (3Al2O3·2SiO2) nanofibers were fabricated by sol–gel and electrospinning techniques and calcined at high temperatures to obtain pure ceramic mullite nanofibers. Detail structural characterizations suggested that the productive rate of electrospun mullite nanofibers were very high and the sintered nanofibers were made of single crystalline grains with size of ∼100 nm.
Exchangeable claim sizes in a compound Poisson‐type process
Authors: Mena Ramsés H. , Nieto‐Barajas Luis E. 
Published: November 2009

AbstractWhen dealing with risk models the typical assumption of independence among claim size distributions is not always satisfied. Here we consider the case when the claim sizes are exchangeable and study the implications when constructing aggregated claims through compound Poisson‐type processes. In particular, exchangeability is achieved through conditional independence, using parametric and nonparametric measures for the conditioning distribution. Bayes' theorem is employed to ensure an arbitrary but fixed marginal distribution for the claim sizes. A full Bayesian analysis of the proposed model is illustrated with a panel‐type data set coming from a Medical Expenditure Panel Survey (MEPS). Copyright © 2009 John Wiley & Sons, Ltd.
Stem cell separation: A bottleneck in stem cell therapy
Authors: Schriebl Kornelia , Lim Shereen , Choo Andre , Tscheliessnig Anne , Jungbauer Alois 
Published: November 2009

AbstractThe substantial progress in embryonic stem cell (ESC) research could lead to new possibilities in the treatment of various diseases. Currently, applications of ESC for cell therapy are impeded by the presence of potentially teratoma‐forming undifferentiated ESC. Thus, a selective and quantitative removal of undifferentiated ESC from a pool of differentiated and undifferentiated cells is essential before cell therapy. We evaluated the highly selective magnetic activated cell sorting (MACS) method for the quantitative removal of undifferentiated ESC. We found that the clearance rates for undifferentiated ESC decreased with decreasing amount of undifferentiated ESC in the cell pool. Using a simplified model calculation we could predict that, assuming an initial purity of 60%, an estimated 31 steps are required to achieve less than 10–1 cell per 109 cells. Thus, a log clearance rate of 10, which would be necessary for a therapeutically application, is hard to achieve. Our work clearly indicates that the current MACS technology is insufficient to meet the purification needs for cell therapy.
Glucosylglycerol and glucosylglycerate as enzyme stabilizers
Authors: Sawangwan Thornthan , Goedl Christiane , Nidetzky Bernd 
Published: November 2009

AbstractCompatible solutes constitute a diverse class of low‐molecular‐mass organic molecules that are accumulated in high intracellular concentrations in response to the external stress of hyperosmolality or high temperature. Many of these compounds like α, α‐trehalose are well known for their stabilizing effect on protein structure and could lead to development of more stable protein formulations. Negatively charged solutes like mannosylglycerate (R‐2‐O‐α‐D‐mannopyranosyl‐glycerate) are widespread among (hyper)thermophilic microorganisms and are thought to be exceptionally potent stabilizers of proteins under high‐temperature denaturation conditions. To further inquire into the role of compound charge for protective function, we have compared two naturally occurring and structurally related solutes, glucosylglycerol (2‐O‐α‐D‐glucopyranosyl‐sn‐glycerol) and glucosylglycerate (R‐2‐O‐α‐D‐glucopyranosyl‐glycerate), as stabilizers of different enzymes undergoing inactivation through elevated temperature or freeze drying, and benchmarked their effects against that of α,α‐trehalose. Glucosylglycerate in concentrations of ≥0.1 M was the most effective in preventing thermally induced loss of enzyme activity of lactate dehydrogenase, mannitol dehydrogenase, starch phosphorylase, and xylose reductase. α,α‐Trehalose could usually be replaced by glucosylglycerol without compromising enzyme stability. Glucosylglycerol and glucosylglycerate afforded substantial (eightfold) protection to mannitol dehydrogenase during freeze drying.
SUMOylation and cell signalling
Authors: Andreou Artemisia M. , Tavernarakis Nektarios 
Published: November 2009

AbstractSUMOylation is a highly transient post‐translational protein modification. Attachment of SUMO to target proteins occurs via a number of specific activating and ligating enzymes that form the SUMO‐substrate complex, and other SUMO‐specific proteases that cleave the covalent bond, thus leaving both SUMO and target protein free for the next round of modification. SUMO modification has major effects on numerous aspects of substrate function, including subcellular localisation, regulation of their target genes, and interactions with other molecules. The modified SUMO‐protein complex is a very transient state, and it thus facilitates rapid response and actions by the cell, when needed. Like phosphorylation, acetylation and ubiquitination, SUMOylation has been associated with a number of cellular processes. In addition to its nuclear role, important sides of mitochondrial activity, stress response signalling and the decision of cells to undergo senescence or apoptosis, have now been shown to involve the SUMO pathway. With ever increasing numbers of reports linking SUMO to human disease, like neurodegeneration and cancer metastasis, it is highly likely that novel and equally important functions of components of the SUMOylation process in cell signalling pathways will be elucidated in the near future.
Accomplishments in genome‐scale in silico modeling for industrial and medical biotechnology
Authors: Milne Caroline B. , Kim Pan‐Jun , Eddy James A. , Price Nathan D. 
Published: November 2009

AbstractDriven by advancements in high‐throughput biological technologies and the growing number of sequenced genomes, the construction of in silico models at the genome scale has provided powerful tools to investigate a vast array of biological systems and applications. Here, we review comprehensively the uses of such models in industrial and medical biotechnology, including biofuel generation, food production, and drug development. While the use of in silico models is still in its early stages for delivering to industry, significant initial successes have been achieved. For the cases presented here, genome‐scale models predict engineering strategies to enhance properties of interest in an organism or to inhibit harmful mechanisms of pathogens. Going forward, genome‐scale in silico models promise to extend their application and analysis scope to become a transformative tool in biotechnology.
Efficient Homogeneous Radical‐Anion Chain Reactions Initiated by Dissociative Electron Transfer to 3,3,6,6‐Tetraaryl‐1,2‐dioxanes
Authors: Stringle Donald L. B. , Magri David C. , Workentin Mark S. 
Published: November 2009

AbstractA series of 3,3,6,6‐tetraaryl‐1,2‐dioxanes (TADs) have been investigated at an inert electrode by using cyclic voltammetry, constant potential electrolysis and digital simulations. The series consists of the phenyl‐substituted TAD (1 a), p‐methoxy‐aryl TADs (1 b, 1 c) and the p‐methoxy/nitro‐bearing TAD (1 d). The heterogeneous electron‐transfer (ET) reduction is dissociative, causing rupture of the oxygen–oxygen bond, which generates a distonic radical‐anion that reacts competitively either by β‐scission fragmentation or ET. Fragmentation of the distonic radical anion yields an alkene, a substituted benzophenone, and a benzophenone radical anion. The benzophenone radical‐anion propagates an efficient homogeneous ET–fragmentation chain reaction that accounts for the potential dependence of the product ratios and the low charge consumption observed in the controlled potential electrolysis experiments. Digital simulation of the experimental cyclic voltammograms allowed for estimates of the rate constants of the heterogeneous ET to the OO bond, and for the rate constants for the β‐scission fragmentation of the distonic radical‐anions. Density functional theory calculations corroborate the differences in the heterogeneous kinetics of the initial dissociative ET. The endoperoxides 1 a–1 c react predominantly by a concerted dissociative ET mechanism, although the data suggests a stepwise dissociative pathway is also competitive. Bearing a nitro‐aryl substituent, 1 d provides a rare example of an endoperoxide that proceeds by a stepwise dissociative ET mechanism. Irrespective of the initial mechanistic details, we find a propagating radical‐anion cycle is a general mechanistic feature.
Total Synthesis of a Diarylheptanoid, Rhoiptelol B
Authors: Reddy Chada Raji , Rao Nagavaram Narsimha , Srikanth Boinapally 
Published: November 2009

AbstractA stereoselective total synthesis of rhoiptelol B has been accomplished for the first time. The four asymmetric centers were efficiently generated through Keck allylation, Jacobson epoxidation Aldol reaction and reductive etherification as the key steps.