bluuebunny/crossref_metadata_2025 huggingface dataset:
The Prone Position During Surgery and its Complications: A Systematic Review and Evidence-Based Guidelines
Authors: Kwee Melissa M. , Ho Yik-Hong , Rozen Warren M.
Published: February 2015

Surgery in the prone position is often a necessity when access to posterior anatomic structures is required. However, many complications are known to be associated with this type of surgery, as physiologic changes occur with increased pressure to anterior structures. While several studies have discussed postoperative vision loss, much fewer studies with lower levels of evidence have addressed other complications. A systematic literature review was conducted using 2 different databases, and 53 papers were regarded as appropriate for inclusion. Qualitative and quantitative analysis was performed. Thirteen complications were identified. Postoperative vision loss and cardiovascular complications, including hypovolemia and cardiac arrest, had the most number of studies and highest level of evidence. Careful planning for optimal positioning, padding, timing, as well as increased vigilance are evidence-based recommendations where operative prone positioning is required.
Acute Cervical Epidural Hematoma, Screw Pullout, and Esophageal Perforation After Anterior Cervical Corpectomy Surgery: Report of a Case
Authors: Li Ye , Zhu Qing-San , Liu Jing-Chen , Wu Yun-Tao
Published: February 2015

To report a series of complications related to anterior cervical surgery in the same patient. There have been many reports of complications related to anterior cervical surgeries. These include cervical hematoma, instrumentation extrusion, or esophageal injury after anterior cervical decompression. However, there have been no reports of all these complications occurring in 1 patient. This is our report of a patient who experienced all 3 of these complications. The patient was a 73-year-old man suffering from cervical spondylotic myelopathy who was treated with C5 anterior cervical corpectomy and fusion with titanium mesh and bone graft. The patient successively experienced cervical hematoma, screw pullout, and esophageal perforation, and was treated accordingly. Although the patient suffered a series of complications after anterior cervical corpectomy, all the complications were treated successfully. It serves as a caution that a first complication such as hematoma in anterior cervical corpectomy with fusion should be given enough attention to prevent further complications.
Totally Laparoscopic Repair of an Ileal and Uterine Iatrogenic Perforation Secondary to Endometrial Curettage
Authors: Vecchio Rosario , Marchese Salvatore , Leanza Vito , Leanza Antonio , Intagliata Eva
Published: February 2015

Small bowel perforation is a unique, serious complication during endometrial biopsy. The authors report a case of a double uterine-ileal perforation totally managed by primary laparoscopic repair. A 63-year-old female was admitted with acute abdomen 2 days after an endometrial curettage. Abdominal X-ray shows signs of pneumoperitoneum. Emergency diagnostic laparoscopy was performed and a uterine-ileal perforation was identified. Repair was accomplished by a totally laparoscopic intracorporeally suturing of the 2 breaches. Postoperative course showed only a delayed ileus and the patient was discharged after 5 days with no complications. When acute abdomen arises following uterine biopsy, a potential iatrogenic intestinal laceration always has to be ruled out. Laparoscopic approach is a quick and safe technique in these cases. Totally laparoscopic primary closure of the iatrogenic ileal laceration may be accomplished with low morbidity.
High Expression of DARPP-32 in Colorectal Cancer Is Associated With Liver Metastases and Predicts Survival for Dukes A and B Patients: Results of a Pilot Study
Authors: Kopljar Mario , Patrlj Leonardo , Korolija-Marinic Dragan , Horzic Matija , Cupurdija Kristijan , Bakota Bore
Published: February 2015

The purpose of this study was to investigate prognostic significance of Dopamine and cAMP-Regulated neuronal Phosphoprotein 32 (DARPP-32) expression in primary colorectal cancer. The study material consisted of clinical and histopathological data of 100 patients operated for colorectal cancer between 1994 and 1997. For immunohistochemical analysis, specific rabbit antibodies for DARPP-32 were used and the percentage of stained tumor cells was calculated under gross magnification (400 times) on a sample of 500 tumor cells. DARPP-32 expression in the primary tumor was significantly greater in patients with distant metastases compared to patients with no distant metastases (p=0.002). In multivariate regression analysis, DARPP-32 expression in the primary tumor was a significant predictor of distant metastases. With a cut-off point of 76.5%, DARPP-32 expression in the primary tumor significantly influenced both overall and disease free survival, especially for Dukes A and B patients (p=0.037). The results of this study indicate that DARPP-32 may be a potential marker of worse prognosis and a valuable tool for managing further adjuvant treatment in patients with stages Dukes A and B colorectal cancer.
No Mortality or Pancreatic Fistula After Full-Thickness Suture Pancreaticogastrostomy in 39 Patients Who Underwent Pancreaticoduodenectomy
Authors: Fatih Ozdemir , Adil Baskiran , Cengiz Ara , Mustafa Ates , Sagir Kahraman Ayşegul , Maras Ozdemir Zeynep , Sezai Yilmaz
Published: February 2015

Pancreaticoduodenectomy is considered the standard operation for periampullary tumors. Despite major advances in pancreatic surgery, pancreatic fistula is still an important cause of morbidity and mortality after pancreaticoduodenectomy. Meticulous surgical technique and proper reconstruction of the pancreas are essential to prevent pancreatic fistula. Pancreaticogastrostomy is a safe method for reconstruction of the pancreas after pancreaticoduodenectomy. Regardless of pancreatic texture or duct diameter, the reconstruction is performed by passing full-thickness sutures through both the anterior and posterior sides of the pancreas. In this study, we report 39 cases of reconstruction with pancreaticogastrostomy after pancreaticoduodenectomy without mortality or pancreatic fistula.
Anatomic Study of Individualized and Improved Pedicle Screw Implantation in the Lower Cervical Spine
Authors: Liu Yuan , Zhang Bin , Dai Min , Xiong Han-chu , Gao Song , Li Bin-hua , Yao Hao-qun , Cao Kai , Liu Zhi-li
Published: February 2015

The objective of this study was to explore a safe, reliable, and effective method for pedicle screw implantation in the lower cervical spine. Recently, a number of studies have shown that cervical pedicle screw fixation is better than roadside steel plate after cervical screw internal fixation within the scope of its indications. However, the difficulty of the former surgery technology is relatively higher and it is much easier to cause many complications. Therefore, domestic and foreign scholars have been positively exploring safer, easier operations and cheaper methods of pedicle screw implantation in the lower cervical spine. The lower cervical spine areas (C3–C7) of 7 adult cadavers were carried out with computed tomography (CT) scans of 1-mm slices. The entry point, angle, and length of the screws were determined by the measurement of CT images in a picture archiving and communication system. The pedicle screws were implanted with the technique of improved Abumi pedicle screw placement in the lab. The accuracy of the screws was evaluated by the Andrew CT classification criteria of pedicle screw position and gross observation after the experiment. A total of 66 screws were implanted in the lower cervical spine, and 90.9% of the screws inserted were found to be in an optimal position. The method of individualized and improved pedicle screw implantation in the lower cervical spine is relatively safe and reliable, which can be considered to be used in the clinic.
Discrete Element Method simulations of the saturation of aeolian sand transport
Authors: Pähtz Thomas , Omeradžić Amir , Carneiro Marcus V. , Araújo Nuno A. M. , Herrmann Hans J.
Published: February 2015

The saturation length of aeolian sand transport (Ls), characterizing the distance needed by wind‐blown sand to adapt to changes in the wind shear, is essential for accurate modeling of the morphodynamics of Earth's sandy landscapes and for explaining the formation and shape of sand dunes. In the last decade, it has become a widely accepted hypothesis that Ls is proportional to the characteristic distance needed by transported particles to reach the wind speed (the “drag length”). Here we challenge this hypothesis. From extensive numerical Discrete Element Method simulations, we find that, for medium and strong winds, , where Vs is the saturated value of the average speed of sand particles traveling above the surface and g is the gravitational constant. We show that this proportionality is consistent with a recent analytical model, in which the drag length is just one of four similarly important length scales relevant for sand transport saturation.
Analysis of a coronal mass ejection and corotating interaction region as they travel from the Sun passing Venus, Earth, Mars, and Saturn
Authors: Prise A. J. , Harra L. K. , Matthews S. A. , Arridge C. S. , Achilleos N.
Published: February 2015

During June 2010 a good alignment in the solar system between Venus, STEREO‐B, Mars, and Saturn provided an excellent opportunity to study the propagation of a coronal mass ejection (CME) and closely occurring corotating interaction region (CIR) from the Sun to Saturn. The CME erupted from the Sun at 01:30 UT on 20 June 2010,with v≈ 600 km s−1, as observed by STEREO‐B, Solar Dynamics Observatory, and SOHO/Large Angle and Spectrometric Coronagraph. It arrived at Venus over 2 days later, some 3.5 days after a CIR is also detected here. The CIR was also observed at STEREO‐B and Mars, prior to the arrival of the CME. The CME is not directed earthward, but the CIR is detected here less than 2 days after its arrival at Mars. Around a month later, a strong compression of the Saturn magnetosphere is observed by Cassini, consistent with the scenario that the CME and CIR have merged into a single solar transient. The arrival times of both the CME and the CIR at different locations were predicted using the ENLIL solar wind model. The arrival time of the CME at Venus, STEREO‐B, and Mars is predicted to within 20 h of its actual detection, but the predictions for the CIR showed greater differences from observations, all over 1.5 days early. More accurate predictions for the CIR were found by extrapolating the travel time between different locations using the arrival times and speeds detected by STEREO‐B and ACE. We discuss the implications of these results for understanding the propagation of solar transients.
Characterizing the low‐altitude magnetic belt at Venus: Complementary observations from the Pioneer Venus Orbiter and Venus Express
Authors: Villarreal M. N. , Russell C. T. , Wei H. Y. , Ma Y. J. , Luhmann J. G. , Strangeway R. J. , Zhang T. L.
Published: February 2015

Using Venus Express, Zhang et al. (2012b) identified strong magnetic field enhancements at low altitudes over the north polar region of Venus as giant flux ropes. Strong fields at low altitudes were also observed during the Pioneer Venus Orbiter mission, but at low latitudes near the subsolar and midnight regions. We examine the possibility that the Venus Express observations are not giant flux ropes, but part of a low‐altitude magnetic belt that builds up in the subsolar region, passes over the terminator, and extends to the nightside. Our analysis indicates the magnetic belt is dominantly horizontal over the dayside and gains a radial component nightward. The peak magnetic field strength of the belt and the altitude at which it peaks also varies around the planet, with the lowest altitude and strongest field strength in the subsolar region, consistent with the idea of the belt forming on the dayside. Zhang et al. (2012b) also noted the fields in the polar region had a bias in the +By direction in Venus Solar Orbital coordinates. The multifluid magnetohydrodynamic simulation we present shows an asymmetry in the plasma flow from the subsolar region to the poles due to the oxygen ion and proton mass ratio. This causes the magnetic field to preferentially accumulate in the north for a +By interplanetary magnetic field direction, providing an explanation for this bias.
Nutrient supply and biological response to wind‐induced mixing, inertial motion, internal waves, and currents in the northern Chukchi Sea
Authors: Nishino Shigeto , Kawaguchi Yusuke , Inoue Jun , Hirawake Toru , Fujiwara Amane , Futsuki Ryosuke , Onodera Jonaotaro , Aoyama Michio
Published: February 2015

A fixed‐point observation station was set up in the northern Chukchi Sea during autumn 2013, and for about 2 weeks conductivity‐temperature‐depth (CTD)/water samplings (6 h) and microstructure turbulence measurements (2 to 3 times a day) were performed. This enabled us to estimate vertical nutrient fluxes and the impact of different types of turbulent mixing on biological activity. There have been no such fixed‐point observations in this region, where incoming low‐salinity water from the Pacific Ocean, river water, and sea‐ice meltwater promote a strong pycnocline (halocline) that stabilizes the water column. Previous studies have suggested that because of the strong pycnocline, wind‐induced ocean mixing could not change the stratification to impact biological activity. However, the present study indicates that a combined effect of an uplifted pycnocline accompanied by wind‐induced inertial motion and turbulent mixing caused by intense gale‐force winds (>10 m s−1) did result in increases in upward nutrient fluxes, primary productivity, and phytoplankton biomass, particularly large phytoplankton such as diatoms. Convective mixing associated with internal waves around the pycnocline also increased the upward nutrient fluxes and might have an impact on biological activity there. For diatom production at the fixed‐point observation station, it was essential that silicate was supplied from a subsurface silicate maximum, a new feature that we identified during autumn in the northern Chukchi Sea. Water mass distributions obtained from wide‐area observations suggest that the subsurface silicate maximum water was possibly derived from the ventilated halocline in the Canada Basin.
Large icebergs characteristics from altimeter waveforms analysis
Authors: Tournadre J. , Bouhier N. , Girard‐Ardhuin F. , Rémy F.
Published: February 2015

Large uncertainties exist on the volume of ice transported by the Southern Ocean large icebergs, a key parameter for climate studies, because of the paucity of information, especially on iceberg thickness. Using icebergs tracks from the National Ice Center (NIC) and Brigham Young University (BYU) databases to select altimeter data over icebergs and a method of analysis of altimeter waveforms, a database of 5366 icebergs freeboard elevation, length, and backscatter covering the 2002–2012 period has been created. The database is analyzed in terms of distributions of freeboard, length, and backscatter showing differences as a function of the iceberg's quadrant of origin. The database allows to analyze the temporal evolution of icebergs and to estimate a melt rate of 35–39 m·yr−1 (neglecting the firn compaction). The total daily volume of ice, estimated by combining the NIC and altimeter sizes and the altimeter freeboards, regularly decreases from 2.2 104km3 in 2002 to 0.9 104km3 in 2012. During this decade, the total loss of ice (
km3·yr−1) is twice as large as than the input (
km3·yr−1) showing that the system is out of equilibrium after a very large input of ice between 1997 and 2002. Breaking into small icebergs represents 80% (
km3·yr−1) of the total ice loss while basal melting is only 18% (
km3·yr−1). Small icebergs are thus the major vector of freshwater input in the Southern Ocean.
The role of ocean gateways in the dynamics and sensitivity to wind stress of the early Antarctic Circumpolar Current
Authors: Munday D. R. , Johnson H. L. , Marshall D. P.
Published: February 2015

The date of inception of the Antarctic Circumpolar Current is debated due to uncertainty in the relative opening times of Drake Passage and the Tasman Seaway. Using an idealized eddy‐resolving numerical ocean model, we investigate whether both ocean gateways have to be open to allow for a substantial circumpolar current. We find that overlapping continental barriers do not impede a circumpolar transport in excess of 50Sv, as long as a circumpolar path can be traced around the barriers. However, the presence of overlapping barriers does lead to an increased sensitivity of the current's volume transport to changes in wind stress. This change in sensitivity is interpreted in terms of the role of pressure drops across continental barriers and submerged bathymetry in balancing the momentum input by the surface wind stress. Specifically, when the pressure drop across continents is the main balancing sink of momentum, the zonal volume transport is sensitive to changes in wind stress. Changes in zonal volume transport take place via altering the depth‐independent part of the circumpolar transport rather than that arising from thermal wind shear. In such a scenario, isopycnals continue to slope steeply across the model Southern Ocean, implying a strong connection between the deep and surface oceans. This may have consequences for the meridional overturning circulation and its sensitivity to wind stress.
Nurturing Genius: Positive Psychology as a Framework for Organization and Practice
Authors: Ambler Virginia M. , Kelly Crace R. , Fisler Jodi
Published: February 2015

Virginia M. Ambler, R. Kelly Crace, and Jodi Fisler, of the College of William & Mary, describe the process of imagining and implementing a student affairs division intentionally structured to support flourishing.
Optical, Electrical, and Magnetic Studies of Organic Solar Cells Based on Low Bandgap Copolymer with Spin ½ Radical Additives
Authors: Basel Tek , Huynh Uyen , Zheng Tianyue , Xu Tao , Yu Luping , Vardeny Z. Valy
Published: February 2015

The charge photogeneration and recombination processes in organic photovoltaic solar cells based on blend of the low bandgap copolymer, PTB7 (fluorinated poly‐thienothiophene‐benzodithiophene) with C60‐PCBM using optical, electrical, and magnetic measurements in thin films and devices is studied. A variety of steady state optical and magneto‐optical techniques were employed, such as photoinduced absorption (PA), magneto‐PA, doping‐induced absorption, and PA‐detected magnetic resonance (PADMR); as well as picosecond time‐resolved PA. The charge polarons and triplet exciton dynamics in films of pristine PTB7, PTB7/fullerene donor–acceptor (D–A) blend is followed. It is found that a major loss mechanism that limits the power conversion efficiency (PCE) of PTB7‐based solar cell devices is the “back reaction” that leads to triplet exciton formation in the polymer donor from the photogenerated charge‐transfer excitons at the D–A interfaces. A method of suppressing this “back reaction” by adding spin½ radicals Galvinoxyl to the D–A blend is presented; this enhances the cell PCE by ≈30%. The same method is not effective for cells based on PTB7/C70‐PCBM blend, where high PCE is reached even without Galvinoxyl radical additives.
Carbonaceous Dye‐Sensitized Solar Cell Photoelectrodes
Authors: Batmunkh Munkhbayar , Biggs Mark J. , Shapter Joseph G.
Published: February 2015

High photovoltaic efficiency is one of the most important keys to the commercialization of dye sensitized solar cells (DSSCs) in the quickly growing renewable electricity generation market. The heart of the DSSC system is a wide bandgap semiconductor based photoelectrode film that helps to adsorb dye molecules and transport the injected electrons away into the electrical circuit. However, charge recombination, poor light harvesting efficiency and slow electron transport of the nanocrystalline oxide photoelectrode film are major issues in the DSSC's performance. Recently, semiconducting composites based on carbonaceous materials (carbon nanoparticles, carbon nanotubes (CNTs), and graphene) have been shown to be promising materials for the photoelectrode of DSSCs due to their fascinating properties and low cost. After a brief introduction to development of nanocrystalline oxide based films, this Review outlines advancements that have been achieved in the application of carbonaceous‐based materials in the photoelectrode of DSSCs and how these advancements have improved performance. In addition, several of the unsolved issues in this research area are discussed and some important future directions are also highlighted.
Copy number variations in children with brain malformations and refractory epilepsy
Authors: Wincent Josephine , Kolbjer Sintia , Martin Daniel , Luthman Aron , Åmark Per , Dahlin Maria , Anderlid Britt‐Marie
Published: February 2015

Brain malformations are a major cause of therapy‐refractory epilepsy as well as neurological and developmental disabilities in children. This study examined the frequency and the nature of copy number variations among children with structural brain malformations and refractory epilepsy. The medical records of all children born between 1990 and 2009 in the epilepsy registry at the Astrid Lindgren's Children's Hospital were reviewed and 86 patients with refractory epilepsy and various brain malformations were identified. Array‐CGH analysis was performed in 76 of the patients. Pathogenic copy number variations were detected in seven children (9.2%). In addition, rearrangements of unclear significance, but possibly pathogenic, were detected in 11 (14.5%) individuals. In 37 (48.7%) patients likely benign, but previously unreported, copy number variants were detected. Thus, a large proportion of our patients had at least one rare copy number variant. Our results suggest that array‐CGH should be considered as a first line genetic test for children with cerebral malformations and refractory epilepsy unless there is a strong evidence for a specific monogenic syndrome. © 2015 Wiley Periodicals, Inc.
Are Angelman and Prader‐Willi syndromes more similar than we thought? Food‐related behavior problems in Angelman, Cornelia de Lange, Fragile X, Prader‐Willi and 1p36 deletion syndromes
Authors: Welham Alice , Lau Johnny King L. , Moss Joanna , Cullen Jenny , Higgs Suzanne , Warren Gemma , Wilde Lucy , Marr Abby , Cook Faye , Oliver Chris
Published: February 2015

Food‐related behavior problems are well documented in Prader–Willi syndrome (PWS), with impaired satiety, preoccupation with food and negative food‐related behaviors (such as taking and storing food) frequently reported as part of the behavioral phenotype of older children and adults. Food‐related behavior problems in other genetic neurodevelopmental syndromes remain less well studied, including those seen in Angelman Syndrome (AS), the ‘sister imprinted disorder’ of PWS. Food‐related behavior problems were assessed in 152 participants each with one of five genetic neurodevelopmental syndromes – PWS, AS, 1p36 deletion, Cornelia de Lange, and fragile X. Predictably, levels of food‐related behavior problems reported in participants with PWS significantly exceeded those of at least one other groups in most areas (impaired satiety; preoccupation with food; taking and storing food; composite negative behavior). However, in some areas people with AS were reported to display food‐related problems at least as severe as those with PWS, with the AS group reported to display significantly more food‐related behavior problems than at least one comparison group on measures of taking and storing food, composite negative behaviors, impaired satiety and preoccupation with food. Over 50% of participants in the AS group scored above the median point of the distribution of PWS scores on a measure of taking and storing food. These findings indicate further investigation of eating problems in AS are warranted and have implications for current theoretical interpretations of the behavioral differences between AS and PWS. © 2015 Wiley Periodicals, Inc.
Expanding the phenotype of Timothy syndrome type 2: An adolescent with ventricular fibrillation but normal development
Authors: Hiippala Anita , Tallila Jonna , Myllykangas Samuel , Koskenvuo Juha W , Alastalo Tero‐Pekka
Published: February 2015

Timothy syndrome is a rare multiorgan disorder with prolonged QTc interval, congenital heart defects, syndactyly, typical facial features and neurodevelopmental problems. Ventricular tachyarrhythmia is the leading cause of death at early age. Classical Timothy syndrome type 1 (TS1) results from a recurrent de novo CACNA1C mutation, G406R in exon 8 A. An atypical form of Timothy syndrome type 2 (TS2) is caused by mutations in G406R and G402S in the alternatively spliced exon 8. Only one individual for each exon 8 mutations has been described. In contrast to multiorgan disease caused by the mutation in G406R either in exon 8 A or 8, the G402S carrier manifested only an isolated cardiac phenotype with LQTS and cardiac arrest. We describe a teenage patient resuscitated from ventricular fibrillation and treated with an implantable cardioverter defibrillator. She has no other organ manifestations, no syndactyly, normal neurodevelopment and her QTc has ranged between 440–480 ms. There is no family history of arrhythmias or sudden death. Targeted oligonucleotide‐selective sequencing (OS‐Seq) of channelopathy genes revealed a de novo substitution, G402S in exon 8 of CACNA1C. Direct sequencing of blood and saliva derived DNA showed an identical mutation peak suggesting ubiquitous expression in different tissues. The phenotype of our patient and the previously described patient show an isolated arrhythmia disease with no other organ manifestations of classical Timothy syndrome. © 2015 Wiley Periodicals, Inc.
Apneas observed in trisomy 18 neonates should be differentiated from epileptic apneas
Authors: Fukasawa Tatsuya , Kubota Tetsuo , Tanaka Masaharu , Asada Hideyuki , Matsusawa Kaname , Hattori Tetsuo , Kato Yuichi , Negoro Tamiko
Published: February 2015

Many children with trisomy 18 have apneas from the neonatal period. It has been reported that some children with trisomy 18 have epilepsy, including epileptic apneas. However, no previous report has described epileptic apneas in trisomy 18 neonates. We retrospectively reviewed the clinical records of neonates with trisomy 18 who were born at Anjo Kosei Hospital between July 2004 and October 2013 and investigated whether they had epileptic apneas during the neonatal period and whether antiepileptic drugs (AEDs) were effective for treating them. We identified 16 patients with trisomy 18. Nine patients who died within 3 days of birth were excluded. Five of the remaining seven patients had apneas. All five patients underwent electroencephalograms (EEGs) to assess whether they suffered epileptic apneas. Three of the five patients had EEG‐confirmed seizures. In two patients, the apneas corresponded to ictal discharges. In one patient, ictal discharges were recorded when she was under mechanical ventilation, but no ictal discharges that corresponded to apneas were recorded after she was extubated. AEDs were effective for treating the apneas and stabilizing the SpO2 in all three patients. Among neonates with trisomy 18 who lived longer than 3 days, three of seven patients had EEG‐confirmed seizures. AEDs were useful for treating their epileptic apneas and stabilizing their SpO2. Physicians should keep epileptic apneas in mind when treating apneas in neonates with trisomy 18. © 2015 Wiley Periodicals, Inc.
Control of Stem‐Cell Behavior by Fine Tuning the Supramolecular Assemblies of Low‐Molecular‐Weight Gelators
Authors: Latxague Laurent , Ramin Michael A. , Appavoo Ananda , Berto Pierre , Maisani Mathieu , Ehret Camille , Chassande Olivier , Barthélémy Philippe
Published: February 2015

Controlling the behavior of stem cells through the supramolecular architecture of the extracellular matrix remains an important challenge in the culture of stem cells. Herein, we report on a new generation of low‐molecular‐weight gelators (LMWG) for the culture of isolated stem cells. The bola‐amphiphile structures derived from nucleolipids feature unique rheological and biological properties suitable for tissue engineering applications. The bola‐amphiphile‐based hydrogel scaffold exhibits the following essential properties: it is nontoxic, easy to handle, injectable, and features a biocompatible rheology. The reported glycosyl‐nucleoside bola‐amphiphiles (GNBA) are the first examples of LMWG that allow the culture of isolated stem cells in a gel matrix. The results (TEM observations and rheology) suggest that the supramolecular organizations of the matrix play a role in the behavior of stem cells in 3D environments.
A Covalent Approach for Site‐Specific RNA Labeling in Mammalian Cells
Authors: Li Fahui , Dong Jianshu , Hu Xiaosong , Gong Weimin , Li Jiasong , Shen Jing , Tian Huifang , Wang Jiangyun
Published: February 2015

Advances in RNA research and RNA nanotechnology depend on the ability to manipulate and probe RNA with high precision through chemical approaches, both in vitro and in mammalian cells. However, covalent RNA labeling methods with scope and versatility comparable to those of current protein labeling strategies are underdeveloped. A method is reported for the site‐ and sequence‐specific covalent labeling of RNAs in mammalian cells by using tRNAIle2‐agmatidine synthetase (Tias) and click chemistry. The crystal structure of Tias in complex with an azide‐bearing agmatine analogue was solved to unravel the structural basis for Tias/substrate recognition. The unique RNA sequence specificity and plastic Tias/substrate recognition enable the site‐specific transfer of azide/alkyne groups to an RNA molecule of interest in vitro and in mammalian cells. Subsequent click chemistry reactions facilitate the versatile labeling, functionalization, and visualization of target RNA.
Cycloparaphenylene‐Based Ionic Donor–Acceptor Supramolecule: Isolation and Characterization of Li+@C60⊂[10]CPP
Authors: Ueno Hiroshi , Nishihara Taishi , Segawa Yasutomo , Itami Kenichiro
Published: February 2015

The first cycloparaphenylene (CPP)‐based ionic donor–acceptor supramolecule Li+@C60⊂[10]CPP⋅X− has been synthesized. X‐ray crystallography not only confirmed the molecular structure of Li+@C60⊂[10]CPP⋅X− but also uncovered the formation of a unique ionic crystal. The strong charge‐transfer interaction between [10]CPP and Li+@C60, which was confirmed by electrochemical measurement and spectroscopic analyses, caused significant delocalization of the positive charge across the entire complex.
Dianions as Formal Oxidants: Synthesis and Characterization of Aromatic Dilithionickeloles from 1,4‐Dilithio‐1,3‐butadienes and [Ni(cod)2]
Authors: Wei Junnian , Zhang Wen‐Xiong , Xi Zhenfeng
Published: February 2015

Organolithium compounds can behave as reductants but never as oxidants in redox reactions. Reported herein is that 1,4‐dilithio‐1,3‐butadienes reacted with [Ni(cod)2] (cod=1,5‐cyclooctadiene) to deliver dilithionickeloles. Single‐crystal X‐ray structural analysis revealed a coplanar structure of dilithionickeloles with an averaging of bond lengths. XPS data confirmed the oxidation state of Ni in dilithionickeloles was Ni2+. 7Li NMR spectra of dilithionickeloles and theoretical calculations revealed a considerable aromatic character. In this redox reaction, the dilithio dianionic compounds behaved as formal oxidants, thus oxidizing Ni0 into Ni2+. These results demonstrated that organolithium compounds with π‐conjugation could be used as oxidants and could continue to accept extra electrons.
Catalytic Asymmetric Inverse‐Electron‐Demand Oxa‐Diels–Alder Reaction of In Situ Generated ortho‐Quinone Methides with 3‐Methyl‐2‐Vinylindoles
Authors: Zhao Jia‐Jia , Sun Si‐Bing , He Sai‐Huan , Wu Qiong , Shi Feng
Published: February 2015

The first catalytic asymmetric inverse‐electron‐demand (IED) oxa‐Diels–Alder reaction of ortho‐quinone methides, generated in situ from ortho‐hydroxybenzyl alcohols, has been established. By selecting 3‐methyl‐2‐vinylindoles as a class of competent dienophiles, this approach provides an efficient strategy to construct an enantioenriched chroman framework with three adjacent stereogenic centers in high yields and excellent stereoselectivities (up to 99 % yield, >95:5 d.r., 99.5:0.5 e.r.). The utilization of ortho‐hydroxybenzyl alcohols as precursors of dienes and 3‐methyl‐2‐vinylindoles as dienophiles, as well as the hydrogen‐bonding activation mode of the substrates met the challenges of a catalytic asymmetric IED oxa‐Diels–Alder reaction.
Impact of titanium and silica/titanium fumed oxide nanofillers on the elastic properties and thermal decomposition of a polyester resin
Authors: Gorelov Borys , Gorb Alla , Korotchenkov Oleg , Nadtochiy Andriy , Polovina Oleksiy , Sigareva Nadia
Published: February 2015

The impact of nanoparticles of titanium (rutile) and silica–titanium fumed oxide (STO) on both the acoustic properties and thermal decomposition of a styrene‐crosslinked unsaturated polyester resin were studied with the methods of ultrasonic probing and thermal decomposition mass spectrometry at filler loadings ranging from 0.5 to 5.0%. It was shown that the elastic modulus, Poisson's ratio, and thermal resistivity in the titanium‐filled nanocomposites increased at small loadings of about 0.5%, whereas in the STO‐filled nanoparticles, the decreases in the parameters at loadings of up to 1.5% was replaced by some increases at higher loadings of up to 5.0%. Distinctions in the concentration dependences of the elastic parameters and the thermal decomposition intensity for both fillers could be explained by the features of the polymer–particle interactions because of the differences in both the number of active sites located on the particle's surface and the polymer structure within interface regions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42010.
Ridge to reef modelling for use within land–sea planning under data‐limited conditions
Authors: Rude Jeremy , Minks Andrew , Doheny Brandon , Tyner Marlene , Maher Katy , Huffard Christine , Hidayat Nur Ismu , Grantham Hedley
Published: February 2015

Soil erosion associated with land‐use change is considered one of the greatest human threats to coral reef ecosystems globally. To account for sediment runoff in land–sea planning, spatially and temporally dynamic models are needed that predict where soil loss is occurring, in addition to where sediments are travelling and settling in coastal marine areas. This assessment is particularly difficult given the complex three‐dimensional movement of sediment in water bodies.

This study assessed the vulnerability of key marine resources to sedimentation in Raja Ampat, Indonesia, by developing a coupled terrestrial and marine model that relied primarily on global datasets. The model predicted the quantities of sediment at river mouths, and the spatial extent over where this sediment disperses in the ocean.

In total, 1850 km2 of coral reefs, marine protected areas, dive sites, pearl farms, and other benthic habitats in Raja Ampat were found within sediment plumes with varying degrees of impact. Two hypothetical land‐use scenarios were created to illustrate the sensitivity of sedimentation on marine resources to development, and to compare future alternative management scenarios. The model provides a powerful tool for planners to understand how land management, and land‐use change might affect marine resources, particularly in data‐limited regions.

Copyright © 2015 John Wiley & Sons, Ltd.
Sociodemographic and Geographic Predictors of Quality of Care in United States Patients With End‐Stage Renal Disease Due to Lupus Nephritis
Authors: Plantinga Laura C. , Drenkard Cristina , Patzer Rachel E. , Klein Mitchel , Kramer Michael R. , Pastan Stephen , Lim S. Sam , McClellan William M.
Published: February 2015

Objective

To describe end‐stage renal disease (ESRD) quality of care (receipt of pre‐ESRD nephrology care, access to kidney transplantation, and placement of permanent vascular access for dialysis) in US patients with ESRD due to lupus nephritis (LN‐ESRD) and to examine whether quality measures differ by patient sociodemographic characteristics or US region.

Methods

National surveillance data on patients in the US in whom treatment for LN‐ESRD was initiated between July 2005 and September 2011 (n = 6,594) were analyzed. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (95% CIs) were determined for each quality measure, according to sociodemographic factors and US region.

Results

Overall, 71% of the patients received nephrology care prior to ESRD. Black and Hispanic patients were less likely than white patients to receive pre‐ESRD care (OR 0.73 [95% CI 0.63–0.85] and OR 0.73 [95% CI 0.60–0.88], respectively) and to be placed on the kidney transplant waitlist within the first year after the start of ESRD (HR 0.78 [95% CI 0.68–0.91] and HR 0.82 [95% CI 0.68–0.98], respectively). Those with Medicaid (HR 0.51 [95% CI 0.44–0.58]) or no insurance (HR 0.36 [95% CI 0.29–0.44]) were less likely than those with private insurance to be placed on the waitlist. Only 24% had a permanent vascular access, and placement was even less likely among the uninsured (OR 0.62 [95% CI 0.49–0.79]). ESRD quality‐of‐care measures varied 2–3‐fold across regions of the US, with patients in the Northeast and Northwest generally having higher probabilities of adequate care.

Conclusion

LN‐ESRD patients have suboptimal ESRD care, particularly with regard to placement of dialysis vascular access. Minority race/ethnicity and lack of private insurance are associated with inadequate ESRD care. Further studies are warranted to examine multilevel barriers to, and develop targeted interventions to improve delivery of, care among patients with LN‐ESRD.
Design and Synthesis of Biotin Analogues Reversibly Binding with Streptavidin
Authors: Yamamoto Tomohiro , Aoki Kiyoshi , Sugiyama Akira , Doi Hirofumi , Kodama Tatsuhiko , Shimizu Yohei , Kanai Motomu
Published: February 2015

Two new biotin analogues, biotin carbonate 5 and biotin carbamate 6, have been synthesized. These molecules were designed to reversibly bind with streptavidin by replacing the hydrogen‐bond donor NH group(s) of biotin’s cyclic urea moiety with oxygen. Biotin carbonate 5 was synthesized from L‐arabinose (7), which furnishes the desired stereochemistry at the 3,4‐cis‐dihydroxy groups, in 11 % overall yield (over 10 steps). Synthesis of biotin carbamate 6 was accomplished from L‐cysteine‐derived chiral aldehyde 33 in 11 % overall yield (over 7 steps). Surface plasmon resonance analysis of water‐soluble biotin carbonate analogue 46 and biotin carbamate analogue 47 revealed that KD values of these compounds for binding to streptavidin were 6.7×10−6 M and 1.7×10−10 M, respectively. These values were remarkably greater than that of biotin (KD=10−15 M), and thus indicate the importance of the nitrogen atoms for the strong binding between biotin and streptavidin.
Enveloped virus‐like particles as vaccines against pathogenic arboviruses
Authors: Pijlman Gorben P.
Published: February 2015

Arthropod‐borne arboviruses form a continuous threat to human and animal health, but few arboviral vaccines are currently available. Advances in expression technology for complex, enveloped virus‐like particles (eVLPs) create new opportunities to develop potent vaccines against pathogenic arboviruses. In this short review, I highlight the successes and challenges in eVLP production for members of the three major arbovirus families: Flaviviridae (e.g., dengue, West Nile, Japanese encephalitis); Bunyaviridae (e.g., Rift Valley fever); and Togaviridae (e.g., chikungunya). The results from pre‐clinical testing will be discussed as well as specific constraints to the large‐scale manufacture and purification of eVLPs, which are complex assemblies of membranes and viral glycoproteins. Insect cells emerge as ideal substrates for correct arboviral glycoprotein folding and posttranslational modification to yield high quality eVLPs. Furthermore, baculovirus expression in insect cell culture is scalable and has a proven safety record in industrial human and veterinary vaccine manufacturing. In conclusion, eVLPs produced in insect cells using modern biotechnology have a realistic potential to be used in novel vaccines against arboviral diseases.
Salts employed in hydrophobic interaction chromatography can change protein structure – insights from protein‐ligand interaction thermodynamics, circular dichroism spectroscopy and small angle X‐ray scattering
Authors: Komaromy Andras Z. , Kulsing Chadin , Boysen Reinhard I. , Hearn Milton T. W.
Published: February 2015

Key requirements of protein purification by hydrophobic interaction chromatography (HIC) are preservation of the tertiary/quaternary structure, maintenance of biological function, and separation of the correctly folded protein from its unfolded forms or aggregates. This study examines the relationship between the HIC retention behavior of hen egg white lysozyme (HEWL) in high concentrations of several kosmotropic salts and its conformation, assessed by circular dichroism (CD) spectroscopy. Further, the physicochemical properties of HEWL in the presence of high concentrations of ammonium sulfate, sodium chloride and magnesium chloride were investigated by small angle X‐ray scattering (SAXS) at different temperatures. Radii of gyration were extrapolated from Guinier approximations and the indirect transform program GNOM with protein‐protein interaction and contrast variation taken into account. A bead model simulation provided information on protein structural changes using ab initio reconstruction with GASBOR. These results correlated to the secondary structure content obtained from CD spectroscopy of HEWL. These changes in SAXS and CD data were consistent with heat capacity ΔCp‐values obtained from van't Hoff plot analyses of the retention data. Collectively, these insights enable informed decisions to be made on the choice of chromatographic conditions, leading to improved separation selectivity and opportunities for innovative column‐assisted protein refolding methods.
Controversies in bariatric surgery
Authors: O'Brien P E
Published: February 2015

Background

There are many controversies related to bariatric surgery. This review explores selected areas.

Methods

A combination of randomized clinical trials (RCTs), systematic reviews and expert opinion have been brought together to highlight areas of importance or conflict.

Results and Conclusion

Metabolic surgery is an increasingly preferred term rather than bariatric or obesity surgery. Reporting should be standardized to include appropriate weight measures, valid disease measures and data on loss to follow-up. There are many putative mechanisms of effect of key bariatric procedures, but satiety and early satiation appear central. Weight loss must be durable. Long-term outcome studies (more than 10-year follow-up) show that biliopancreatic diversion is most effective, with 72 per cent excess weight loss (EWL). Roux-en-Y gastric bypass and laparoscopic adjustable gastric banding (LAGB) are equally effective, with 54 per cent EWL. There are no long-term data on vertical sleeve gastrectomy. Type II diabetes is a common and serious disease, usually associated with increased weight. Multiple RCTs have shown that bariatric surgery provides clear benefits over continuing with non-surgical therapies. The earlier the treatment, the more likely and durable will be the remission. Bariatric surgery should be available to all who are obese (body mass index over 30 kg/m2). LAGB, a safe, effective, reversible outpatient procedure, is the author's preferred primary option.
Mechanosensitive Membrane Probes
Authors: Dal Molin Marta , Verolet Quentin , Soleimanpour Saeideh , Matile Stefan
Published: February 2015

This article assembles pertinent insights behind the concept of planarizable push–pull probes. As a response to the planarization of their polarized ground state, a red shift of their excitation maximum is expected to report on either the disorder, the tension, or the potential of biomembranes. The combination of chromophore planarization and polarization contributes to various, usually more complex processes in nature. Examples include the color change of crabs or lobsters during cooking or the chemistry of vision, particularly color vision. The summary of lessons from nature is followed by an overview of mechanosensitive organic materials. Although often twisted and sometimes also polarized, their change of color under pressure usually originates from changes in their crystal packing. Intriguing exceptions include the planarization of several elegantly twisted phenylethynyl oligomers and polymers. Also mechanosensitive probes in plastics usually respond to stretching by disassembly. True ground‐state planarization in response to molecular recognition is best exemplified with the binding of thoughtfully twisted cationic polythiophenes to single‐ and double‐stranded oligonucleotides. Molecular rotors, en vogue as viscosity sensors in cells, operate by deplanarization of the first excited state. Pertinent recent examples are described, focusing on λ‐ratiometry and intracellular targeting. Complementary to planarization of the ground state with twisted push–pull probes, molecular rotors report on environmental changes with quenching or shifts in emission rather than absorption. The labeling of mechanosensitive channels is discussed as a bioengineering approach to bypass the challenge to create molecular mechanosensitivity and use biological systems instead to sense membrane tension. With planarizable push–pull probes, this challenge is met not with twistome screening, but with “fluorescent flippers,” a new concept to insert large and bright monomers into oligomeric probes to really feel the environment and also shine when twisted out of conjugation.
Carbon Dots (C‐dots) from Cow Manure with Impressive Subcellular Selectivity Tuned by Simple Chemical Modification
Authors: D'Angelis do E. S. Barbosa Cintya , Corrêa José R. , Medeiros Gisele A. , Barreto Gabrielle , Magalhães Kelly G. , de Oliveira Aline L. , Spencer John , Rodrigues Marcelo O. , Neto Brenno A. D.
Published: February 2015

Improved cellular selectivity for nucleoli staining was achieved by simple chemical modification of carbon dots (C‐dots) synthesized from waste carbon sources such as cow manure (or from glucose). The C‐dots were characterized and functionalized (amine‐passivated) with ethylenediamine, affording amide bonds that resulted in bright green fluorescence. The new modified C‐dots were successfully applied as selective live‐cell fluorescence imaging probes with impressive subcellular selectivity and the ability to selectively stain nucleoli in breast cancer cell lineages (MCF‐7). The C‐dots were also tested in four other cellular models and showed the same cellular selection in live‐cell imaging experiments.
Immobilization and Continuous Recycling of Photoredox Catalysts in Ionic Liquids for Applications in Batch Reactions and Flow Systems: Catalytic Alkene Isomerization by Using Visible Light
Authors: Fabry David C. , Ronge Meria A. , Rueping Magnus
Published: February 2015

A catalytic (E)‐ to (Z)‐isomerization of olefins using a photoredox catalyst under mild reaction conditions is presented. A variety of (Z)‐alkenes can be prepared in the presence of visible light. A new reaction system allows an easy and efficient scale‐up, as well as a continuous flow process in which the photocatalyst is immobilized in an ionic liquid and continuously recycled by simple phase separation.