bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnesium Complexes Containing η1‐ and η3‐Pyrrolyl or Ketiminato Ligands: Synthesis, Structural Investigation and ϵ‐Caprolactone Ring‐Opening Polymerisation
Authors: Hsueh Li‐Feng , Chuang Nien‐Tsu , Lee Cheng‐Yuan , Datta Amitabha , Huang Jui‐Hsien , Lee Ting‐Yu 
Published: November 2011

AbstractA series of dimeric magnesium derivatives containing substituted pyrrolyl or ketiminato ligands was synthesised and the application of these derivatives for the ring opening polymerisation of ϵ‐caprolactone has been carried out. Reactions of [Mg{N(SiMe3)2}]2 (1) with one equiv. of 2‐dimethylaminomethyl pyrrole and 2‐diethylaminomethyl pyrrole in toluene generates [Mg{C4H3N(2‐CH2NMe2)}{N(SiMe3)2}]2 (2) and [Mg{C4H3N(2‐CH2NEt2)}{N(SiMe3)2}]2 (3), respectively, in high yield. Similarly, the reaction of 1 with one equiv. of 2‐tert‐butylaminomethyl pyrrole in toluene at room temperature affords [Mg{C4H3N(2‐CH2NHtBu)}{N(SiMe3)2}]2 (4). Furthermore, reactions of 1 with one equiv. of HOCMeCHCMeN(C6H3‐2,6‐iPr2) or HOCMeCHCMeN(C6H4‐2‐OMe) in toluene yielded the dimeric magnesium complexes, [Mg{OCMeCHCMeN(C6H3‐2,6‐iPr2)}{N(SiMe3)2}]2 (5) and [Mg{OCMeCHCMeN(C6H4‐2‐OMe)}{N(SiMe3)2}]2 (6), respectively, in satisfactory yields by means of deamination. All the complexes were characterised by NMR spectroscopy and X‐ray diffraction analysis in the solid state. They show moderate reactivity towards the ring opening polymerisation of ϵ‐caprolactone in dichloromethane or tetrahydrofuran.
Rapid and direct quantitative analysis of positional fatty acids in triacylglycerols using 13C NMR
Authors: Gouk Shiou Wah , Cheng Sit Foon , Ong Augustine Soon Hock , Chuah Cheng Hock 
Published: November 2011

AbstractThere is increasing evidence that the positional fatty acid composition (FAC) of TAG is more important than total FAC with regard to nutrition values of edible oils and fats. A rapid and direct regiospecific analysis of positional fatty acids in TAG using 13C NMR was developed to overcome the tedious conventional methods which involve enzymatic hydrolysis, Grignard chemical degradation, and chromatography analysis. A set of NMR data acquisition parameters and processing methods had proven their excellent versatility and applicability on various types of oils and fats, with systematic error of 1.0 mol%. It was found that there are discrepancies between the regiospecific analysis results obtained by the current method and by conventional methods. Probable acyl migration occurring in the hydrolysis process in conventional methods is a noted problem. As the current 13C NMR method is a direct measurement and no hydrolysis of the sample is needed, acyl migration during the analysis is eliminated. As a result, the saturation level is always higher at sn‐1, 3 positions and lower at sn‐2 position in TAG structure of oils in the regiospecific data obtained from the current 13C NMR than that from conventional methods. In the absence of laborious chemical derivatization, this method is simple, accurate, and user‐friendly for researchers, especially for nutritionists to support their nutritional studies from the perspective of positional FAC of edible oils and fats.
Mimicking Nature to Make Unnatural Amino Acids and Chiral Diamines
Authors: So Soon Mog , Kim Hyunwoo , Mui Leo , Chin Jik 
Published: November 2011

AbstractBiomimetic studies of pyridoxal and pyridoxamine models are of both fundamental and practical interest. This review examines (i) deracemization of α‐amino acids with a chiral pyridoxal model, (ii) sensing of chirality of small molecules including α‐, β‐, and γ‐amino acids, peptides, amino alcohols and diamines with an achiral pyridoxal model and (iii) stereospecific synthesis of chiral diamines with a chiral pyridoxamine model. A binol‐based aldehyde is useful as a chiral pyridoxal model to deracemize a variety of α‐amino acids to make D‐amino acids. 2,2′‐Dihydroxybenzophenone is useful as an achiral pyridoxal model for sensing the chirality of the above‐mentioned small molecules in a unified way. Bis(2‐hydroxyphenyl)‐ethylenediamine (hpen) is useful as a chiral pyridoxamine model for making chiral diamines. Weak forces (H‐bonding, steric and electronic effects) involved in transamination reactions with pyridoxamine for the synthesis of amino acids are compared with those for the diaza‐Cope rearrangement reaction with hpen for the synthesis of chiral diamines. Both experimental and computational methods are used to analyze the biomimetic systems.
Albumin infusion in patients undergoing large-volume paracentesis: A meta-analysis of randomized trials
Authors: Bernardi Mauro , Caraceni Paolo , Navickis Roberta J. , Wilkes Mahlon M. 
Published: November 2011

Abstract

Albumin infusion reduces the incidence of postparacentesis circulatory dysfunction among patients with cirrhosis and tense ascites, as compared with no treatment. Treatment alternatives to albumin, such as artificial colloids and vasoconstrictors, have been widely investigated. The aim of this meta-analysis was to determine whether morbidity and mortality differ between patients receiving albumin versus alternative treatments. The meta-analysis included randomized trials evaluating albumin infusion in patients with tense ascites. Primary endpoints were postparacentesis circulatory dysfunction, hyponatremia, and mortality. Eligible trials were sought by multiple methods, including computer searches of bibliographic and abstract databases and the Cochrane Library. Results were quantitatively combined under a fixed-effects model. Seventeen trials with 1,225 total patients were included. There was no evidence of heterogeneity or publication bias. Compared with alternative treatments, albumin reduced the incidence of postparacentesis circulatory dysfunction (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.27–0.55). Significant reductions in that complication by albumin were also shown in subgroup analyses versus each of the other volume expanders tested (e.g., dextran, gelatin, hydroxyethyl starch, and hypertonic saline). The occurrence of hyponatremia was also decreased by albumin, compared with alternative treatments (OR, 0.58; 95% CI, 0.39–0.87). In addition, mortality was lower in patients receiving albumin than alternative treatments (OR, 0.64; 95% CI, 0.41–0.98). Conclusions: This meta-analysis provides evidence that albumin reduces morbidity and mortality among patients with tense ascites undergoing large-volume paracentesis, as compared with alternative treatments investigated thus far. (Hepatology 2012)
The association between fracture and obesity is site-dependent: A population-based study in postmenopausal women
Authors: Prieto-Alhambra Daniel , Premaor Melissa O , Fina Avilés Francesc , Hermosilla Eduard , Martinez-Laguna Daniel , Carbonell-Abella Cristina , Nogués Xavier , Compston Juliet E , Díez-Pérez Adolfo 
Published: November 2011

Abstract
The association between obesity and fracture is controversial. We investigated the relationship between body mass index (BMI) and fracture at different skeletal sites in women aged ≥50 years using data from the Sistema d' Informació per al Desenvolupament de la Investigació en Atenció Primària (SIDIAP) database. SIDIAP contains the computerized medical records of &gt;3400 general practitioners in Catalonia (northeastern Spain), with information on a representative 80% of the population (&gt;5 million people). In 2009, 1,039,878 women aged ≥50 years were eligible, of whom 832,775 (80.1%) had a BMI measurement. These were categorized into underweight/normal (302,414 women), overweight (266,798), and obese (263,563). Fractures were ascertained using the International Classification of Diseases, 10th revision (ICD-10) codes. Multivariate Poisson regression models were fitted to adjust for age, smoking, high alcohol intake, type 2 diabetes, and oral corticosteroid use. Hip fractures were significantly less common in overweight and obese women than in normal/underweight women (rate ratio [RR] 0.77 [95% confidence interval (CI) 0.68 to 0.88], RR 0.63 [95% CI 0.64 to 0.79], p &lt; 0.001, respectively). Pelvis fracture rates were lower in the overweight (RR 0.78 [95% CI 0.63 to 0.96], p = 0.017) and obese (RR 0.58 [95% CI 0.47 to 0.73], p &lt; 0.001) groups. Conversely, obese women were at significantly higher risk of proximal humerus fracture than the normal/underweight group (RR 1.28 [95% CI 1.04 to 1.58], p = 0.018). Clinical spine, wrist, tibial, and multiple rib fracture rates were not significantly different between groups. An age-related increase in incidence was seen for all BMI groups at all fracture sites; obese women with hip, clinical spine, and pelvis fracture were significantly younger at the time of fracture than normal/underweight women, whereas those with wrist fracture were significantly older. The association between obesity and fracture in postmenopausal women is site-dependent, obesity being protective against hip and pelvis fractures but associated with an almost 30% increase in risk for proximal humerus fractures when compared with normal/underweight women. The reasons for these site-specific variations are unknown but may be related to different patterns of falls and attenuation of their impact by adipose tissue. © 2012 American Society for Bone and Mineral Research
Relationship of age to bone microstructure independent of areal bone mineral density
Authors: Nicks Kristy M , Amin Shreyasee , Atkinson Elizabeth J , Riggs B Lawrence , Melton L Joseph , Khosla Sundeep 
Published: November 2011

Abstract
Previous studies using dual-energy X-ray absorptiometry (DXA) have demonstrated that age is a major predictor of bone fragility and fracture risk independent of areal bone mineral density (aBMD). Although this aBMD-independent effect of age has been attributed to poor bone “quality,” the structural basis for this remains unclear. Because high-resolution peripheral quantitative computed tomography (HRpQCT) can assess bone microarchitecture, we matched younger and older subjects for aBMD at the ultradistal radius and assessed for possible differences in trabecular or cortical microstructure by HRpQCT. From an age-stratified, random sample of community adults, 44 women aged &lt;50 years (mean age 41.0 years) were matched to 44 women aged ≥50 years (mean age 62.7 years) by ultradistal radius aBMD (mean ± SEM, younger and older aBMD 0.475 ± 0.011 and 0.472 ± 0.011 g/cm2, respectively), and 57 men aged &lt;50 years (mean age 41.3 years) were matched to 57 men aged ≥50 years (mean age 68.1 years; younger and older aBMD both 0.571 ± 0.008 g/cm2). In these matched subjects, there were no sex-specific differences in trabecular microstructural parameters. However, significant differences were noted in cortical microstructure (all p &lt; 0.05): Older women and men had increased cortical porosity (by 91% and 56%, respectively), total cortical pore volume (by 77% and 61%, respectively), and mean cortical pore diameter (by 9% and 8%, respectively) compared with younger subjects. These findings indicate that younger and older women and men matched for DXA aBMD have similar trabecular microarchitecture but clearly different cortical microstructure, at least at an appendicular site represented by the radius. Further studies are needed to define the extent to which this deterioration in cortical microstructure contributes to the aBMD-independent effect of age on bone fragility and fracture risk at the distal radius and other sites of osteoporotic fractures. © 2012 American Society for Bone and Mineral Research
Relationship between bone mineral density changes with denosumab treatment and risk reduction for vertebral and nonvertebral fractures
Authors: Austin Matthew , Yang Yu-Ching , Vittinghoff Eric , Adami Silvano , Boonen Steven , Bauer Douglas C , Bianchi Gerolamo , Bolognese Michael A , Christiansen Claus , Eastell Richard , Grauer Andreas , Hawkins Federico , Kendler David L , Oliveri Beatriz , McClung Michael R , Reid Ian R , Siris Ethel S , Zanchetta Jose , Zerbini Cristiano AF , Libanati Cesar , Cummings Steven R ,   for the FREEDOM Trial
Published: November 2011

Abstract
Dual-energy X-ray absorptiometric bone mineral density (DXA BMD) is a strong predictor of fracture risk in untreated patients. However, previous patient-level studies suggest that BMD changes explain little of the fracture risk reduction observed with osteoporosis treatment. We investigated the relevance of DXA BMD changes as a predictor for fracture risk reduction using data from the FREEDOM trial, which randomly assigned placebo or denosumab 60 mg every 6 months to 7808 women aged 60 to 90 years with a spine or total hip BMD T-score &lt; −2.5 and not &lt; −4.0. We took a standard approach to estimate the percent of treatment effect explained using percent changes in BMD at a single visit (months 12, 24, or 36). We also applied a novel approach using estimated percent changes in BMD from baseline at the time of fracture occurrence (time-dependent models). Denosumab significantly increased total hip BMD by 3.2%, 4.4%, and 5.0% at 12, 24, and 36 months, respectively. Denosumab decreased the risk of new vertebral fractures by 68% (p &lt; 0.0001) and nonvertebral fracture by 20% (p = 0.01) over 36 months. Regardless of the method used, the change in total hip BMD explained a considerable proportion of the effect of denosumab in reducing new or worsening vertebral fracture risk (35% [95% confidence interval (CI): 20%–61%] and 51% [95% CI: 39%–66%] accounted for by percent change at month 36 and change in time-dependent BMD, respectively) and explained a considerable amount of the reduction in nonvertebral fracture risk (87% [95% CI: 35% – &gt;100%] and 72% [95% CI: 24% – &gt;100%], respectively). Previous patient-level studies may have underestimated the strength of the relationship between BMD change and the effect of treatment on fracture risk or this relationship may be unique to denosumab. © 2012 American Society for Bone and Mineral Research
Real‐time gene delivery vector tracking in the endo‐lysosomal pathway of live cells
Authors: Suh Junghae , An Yoojin , Tang Benjamin C. , Dempsey Christopher , Huang Feiran , Hanes Justin 
Published: November 2011

AbstractUsing live‐cell confocal microscopy and particle tracking technology, the simultaneous transport of intracellular vesicles of the endo‐lysosomal pathway and nonviral polyethylenimine (PEI)/DNA nanocomplexes was investigated. Due to potential problems associated with the use of acid‐sensitive probes in combination with a gene vector that is hypothesized to buffer the pH of intracellular vesicles, the biological location of PEI/DNA gene vectors was revealed by probing their trafficking in cells expressing fluorescent versions of either early endosome antigen 1, a protein that localizes to early endosomes, or Niemann Pick C1, a protein that localizes to late endosomes and lysosomes. Studies directly show that PEI/DNA nanoparticles are actively transported within both early and late endosomes, and display similar overall transport rates in each. Additionally, gene vector transfer between endosomes is observed. Over time post‐transfection, gene vectors accumulate in late endosomes/lysosomes; however, real‐time escape of vectors from membrane‐bound vesicles is not observed. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
Color tuning by local sputtering metal nanolayer on microstructured porous alumina
Authors: Wang Xulongqi , Zhang Haijun , Zhang Dongxian , Ma Yi , Fecht H.‐J. , Jiang J. Z. 
Published: November 2011

AbstractThis article reports a novel color tuning method by local sputtering nanolayers on microstructured porous alumina (PA) templates with different pore depths. With the aid of scanning electron microscopy observation, physical models of the original and sputtered PA templates are set up, and the details of the color tuning method are further proposed. Two series of colors covering the whole visible range are first obtained by respectively sputtering Cr and Ag nanolayers on two groups of PA templates with pore‐depths ranging from 230 to 490 nm. A vivid colorful pattern of “Butterfly wings” is then prepared by local sputtering such Cr and Ag nanolayers on the surface of a PA with 310 nm pore‐depth. The scanning electron microscopy images of Cr and Ag sputtered PA surfaces show different microstructures, which is in agreement with different color exhibiting. This method is expected to have a potential of being widely applied in the fields of micro‐optics, microstructures, advanced materials, and micro/nanotechnology. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
High‐capacity adenoviral vectors circumvent the limitations of ΔE1 and ΔE1/ΔE3 adenovirus vectors to induce multispecific transgene product‐directed CD8 T‐cell responses
Authors: Kron Matthias W. , Engler Tatjana , Schmidt Erika , Schirmbeck Reinhold , Kochanek Stefan , Kreppel Florian 
Published: November 2011

AbstractBackgroundThe ability to induce cytotoxic T lymphocyte (CTL) responses that are multispecific is considered to comprise an essential feature for an efficacious genetic vaccine against many pathogens including HIV and hepatitis C virus. ΔE1Ad vectors are promising vectored vaccines but have been shown to induce antigen‐specific CTLs with only limited multispecificity. In the present study, we investigated the applicability of gene‐deleted high‐capacity adenovirus (HC‐Ad) vectors and focused on the induction of multispecific CTL responses.MethodsWe generated ΔE1 and HC‐Ad vectors expressing hepatitis B virus small surface antigen (HBsAg). We comparatively analyzed the CTL profiles against various transgene product‐ and vector‐derived epitopes in several mouse strains and HBsAg‐ and vector‐directed antibody responses.ResultsHC‐Ad vectors efficiently induced multispecific HBsAg‐directed CTLs. By contrast, ΔE1Ad vectors mainly primed CTLs against one immunodominant epitope of HBsAg. This absence of multispecific CTL responses correlated with the induction of CTLs against viral epitopes generated by de novo expression of Ad genes from the ΔE1Ad vector. However, Ad‐specific CTLs induced in trans did not impair HC‐AdS‐induced multispecific CTL responses against HBsAg. Finally, HC‐Ad vectors also induced higher HBsAg antibody titers compared to ΔE1Ad vectors.ConclusionsDe novo expression of viral genes from ΔE1Ad vector genomes restricts the multispecificity of transgene product‐specific CTLs by immunodominance effects. HC‐Ad vectors devoid of Ad genes are favorable for the induction of both multispecific CD8 T‐cell responses and high antibody responses. Our results suggest the deletion of Ad genes as an important means for developing potent Ad‐based vectored vaccines. Copyright © 2011 John Wiley & Sons, Ltd.
Use of UpToDate and outcomes in US hospitals
Authors: Isaac Thomas , Zheng Jie , Jha Ashish 
Published: November 2011

AbstractBACKGROUND:Computerized clinical knowledge mana‐gement systems hold enormous potential for improving quality and efficiency. However, their impact on clinical practice is not well known.OBJECTIVE:To examine the impact of UpToDate on outcomes of care.DESIGN:Retrospective study.SETTING:National sample of US inpatient hospitals.PATIENTS:Fee‐for‐service Medicare beneficiaries.INTERVENTION:Adoption of UpToDate in US hospitals.MEASUREMENT:Risk‐adjusted lengths of stay, mortality rates, and quality performance.RESULTS:We found that patients admitted to hospitals using UpToDate had shorter lengths of stay than patients admitted to non‐UpToDate hospitals overall (5.6 days vs 5.7 days; P < 0.001) and among 6 prespecified conditions (range, −0.1 to −0.3 days; P < 0.001 for each). Further, patients admitted to UpToDate hospitals had lower risk‐adjusted mortality rate for 3 of the 6 conditions (range, −0.1% to −0.6% mortality reduction; P < 0.05). Finally, hospitals with UpToDate had better quality performance for every condition on the Hospital Quality Alliance metrics. In subgroup analyses, we found that it was the smaller hospitals and the non‐teaching hospitals where the benefits of the UpToDate seemed most pronounced, compared to the larger, teaching institutions where the benefits of UpToDate seemed small or nonexistent.CONCLUSIONS:We found a very small but consistent association between use of UpToDate and reduced length of stay, lower risk‐adjusted mortality rates, and better quality performance, at least in the smaller, non‐teaching institutions. These findings may suggest that computerized tools such as UpToDate could be helpful in improving care. Journal of Hospital Medicine 2012. © 2011 Society of Hospital Medicine.
High resolution three‐dimensional cine phase contrast MRI of small intracranial aneurysms using a stack of stars k‐space trajectory
Authors: Kecskemeti Steven , Johnson Kevin , Wu Yijing , Mistretta Charles , Turski Patrick , Wieben Oliver 
Published: November 2011

AbstractPurpose:To develop a method for targeted volumetric, three directional cine phase contrast (PC) imaging with high spatial resolution in clinically feasible scan times.Materials and Methods:A hybrid radial‐Cartesian k‐space trajectory is used for cardiac gated, volumetric imaging with three directional velocity encoding. Imaging times are reduced by radial undersampling and temporal viewsharing. Phase contrast angiograms are displayed in a new approach that addresses the concern of signal drop out in regions of slow flow. The feasibility of the PC stack of stars (SOS) trajectory was demonstrated with an in vivo study capturing 14 small intracranial aneurysms (2–10 mm). Aneurysm measures from six aneurysms also imaged with digital subtraction angiography (DSA) were compared with linear regression with those from the PC SOS images.Results:All aneurysms were identified on the phase contrast angiograms. The geometric measures from PC SOS and DSA were in good agreement (linear regression: slope = 0.89, intercept = 0.35, R∧2 = 0.88).Conclusion:PC SOS is a promising method for obtaining volumetric angiograms and cine phase contrast velocity measurements in three dimensions. Acquired spatial resolutions of 0.4 × 0.4 × (0.7–1.0) mm make this method especially promising for studying flow in small intracranial aneurysms. J. Magn. Reson. Imaging 2012;35:518‐527. © 2011 Wiley Periodicals, Inc.
Inversion‐recovery‐prepared dixon bSSFP: Initial clinical experience with a novel pulse sequence for renal MRA within a breathhold
Authors: Worters Pauline W. , Saranathan Manojkumar , Xu Alan , Vasanawala Shreyas S. 
Published: November 2011

AbstractPurpose:To evaluate the capability of a new breathhold non–contrast‐enhanced MRA method (Non‐contrast Outer Radial Inner Square k‐space Scheme, NORISKS) to visualize renal arteries by comparing the method with a routine clinical but significantly longer non–contrast‐enhanced (non‐CE) MRA technique.Materials and Methods:Eighteen subjects referred for abdominal MRI were examined with NORISKS and a routine non–contrast‐enhanced MRA technique. Two versions of NORISKS were evaluated: with and without ECG gating. The images were then scored independently and in blinded manner by two radiologists on 5‐point scales for visualization of the proximal and distal renal arteries and quality of fat suppression.Results:No statistically significant difference was detected between NORISKS and routine clinical non‐CE MRA in all categories except for visualization of the distal renal arteries where ungated NORISKS performed poorer than the routine non‐CE MRA (P < 10−4).Conclusion:We have demonstrated a promising non‐CE MRA method for acquiring renal angiograms within a breathhold without any compromise in spatial resolution or coverage. ECG‐gated NORISKS is able to acquire renal angiograms that are comparable to a routine clinical non‐CE MRA method (Inhance IFIR, GE Healthcare), which requires approximately seven times the scan time of NORISKS. J. Magn. Reson. Imaging 2012;35:875–881. © 2011 Wiley Periodicals, Inc.