bluuebunny/crossref_metadata_2025_split huggingface dataset:
Single‐walled carbon nanotubes as near‐infrared optical biosensors for life sciences and biomedicine
Authors: Jain Astha , Homayoun Aida , Bannister Christopher W. , Yum Kyungsuk 
Published: February 2015

AbstractSingle‐walled carbon nanotubes that emit photostable near‐infrared fluorescence have emerged as near‐infrared optical biosensors for life sciences and biomedicine. Since the discovery of their near‐infrared fluorescence, researchers have engineered single‐walled carbon nanotubes to function as an optical biosensor that selectively modulates its fluorescence upon binding of target molecules. Here we review the recent advances in the single‐walled carbon nanotube‐based optical sensing technology for life sciences and biomedicine. We discuss the structure and optical properties of single‐walled carbon nanotubes, the mechanisms for molecular recognition and signal transduction in single‐walled carbon nanotube complexes, and the recent development of various single‐walled carbon nanotube‐based optical biosensors. We also discuss the opportunities and challenges to translate this emerging technology into biomedical research and clinical use, including the biological safety of single‐walled carbon nanotubes. The advances in single‐walled carbon nanotube‐based near‐infrared optical sensing technology open up a new avenue for in vitro and in vivo biosensing with high sensitivity and high spatial resolution, beneficial for many areas of life sciences and biomedicine.
Directed evolution of phenylacetone monooxygenase as an active catalyst for the baeyer–villiger conversion of cyclohexanone to caprolactone
Authors: Parra Loreto P. , Acevedo Juan P. , Reetz Manfred T. 
Published: February 2015

ABSTRACTPhenylacetone monooxygenase (PAMO) is an exceptionally robust Baeyer–Villiger monooxygenase, which makes it ideal for potential industrial applications. However, its substrate scope is limited, unreactive cyclohexanone being a prominent example. Such a limitation is unfortunate, because this particular transformation in an ecologically viable manner would be highly desirable, the lactone and the respective lactam being of considerable interest as monomers in polymer science. We have applied directed evolution in search of an active mutant for this valuable C‐C activating reaction. Using iterative saturation mutagenesis (ISM), several active mutants were evolved, with only a minimal trade‐off in terms of stability. The best mutants allow for quantitative conversion of 2 mM cyclohexanone within 1 h reaction time. In order to circumvent the NADP+ regeneration problem, whole E. coli resting cells were successfully applied. Molecular dynamics simulations and induced fit docking throw light on the origin of enhanced PAMO activity. The PAMO mutants constitute ideal starting points for future directed evolution optimization necessary for an industrial process. Biotechnol. Bioeng. 2015;112: 1354–1364. © 2015 Wiley Periodicals, Inc.
Entwicklung von RNA‐basierten Impfstoffen
Authors: Roos Tilmann 
Published: February 2015

AbstractTrotz substanzieller Verbesserungen in der Entwicklung von Influenzavakzinen bleiben die Herstellung und Verfügbarkeit der Impfstoffe suboptimal. mRNA‐basierte Impfstoffe bieten eine Alternative, da sie schnell, flexibel und skalierbar produziert werden können. Sogar nach thermischem Stress bleibt die Wirksamkeit des Impfstoffes voll erhalten und demonstriert so Stabilität der neuen Wirkstoffklasse. Die Fähigkeit der mRNA‐basierten Impfstoffe, eine langlebige sowohl humorale als auch zelluläre Immunität zu generieren, macht sie zu einer neuen Vakzin‐Plattform, die nicht nur in der Infektionsprophylaxe, sondern auch in der Tumortherapie zum Einsatz kommen kann.
Selbstreparatur in Natur und Technik
Authors: Speck Olga , Speck Thomas 
Published: February 2015

AbstractPflanzen haben im Laufe der Evolution mehrfach unabhängig voneinander Selbstreparaturmechanismen entwickelt. Seit Jahren wird in interdisziplinären Forschungsprojekten an der Entwicklung von bioinspirierten Materialien und Strukturen mit Selbstreparatureffekt gearbeitet. Vorbild für eine bionische selbstreparierende Schaumbeschichtung bei pneumatischen Systemen waren die parenchymatischen Reparaturzellen der Pfeifenwinde (Aristolochia macrophylla), die im Laufe des Wachstums entstehende Risse im Stängelinneren rasch versiegeln. Einen bisher nicht bekannten Selbstreparaturmechanismus zeigen die sukkulenten Blätter des Mittagblumengewächses Delosperma cooperi. Nach einer äußeren Verletzung bewegen sich die Blätter so lange, bis die Wunde ganz versiegelt ist. Mit der Beschreibung eines mathematischen Fünf‐Schalen‐Modells sind die Voraussetzungen für die Entwicklung eines selbstreparierenden technischen Schichtmaterials erfüllt.
Bakterienresistente Bananen für Ostafrika
Authors: Brennicke Axel 
Published: February 2015

AbstractIn Ostafrika sind Bananen ein Hauptnahrungsmittel, das meist von den vielen Kleinbauern produziert wird. Seit einigen Jahren breitet sich von Äthiopien her eine für Bananenstauden tödliche Infektion mit einem Bakterium aus. Die Züchtung resistenter Bananen ist äußerst schwierig, da Bananen über Stecklinge vermehrt werden. Jetzt zeigen Feldversuche mit genetisch veränderten Bananenpflanzen Erfolg. Die transgenen Pflanzen sollen den Kleinbauern kostenlos zur Verfügung gestellt werden.
Erlebniswelt Gartenteich: von Ringelnattern, Gelbrandkäfern und Libellen
Authors: Petrischak Hannes 
Published: February 2015

AbstractEin Gartenteich bietet über und unter Wasser eine Fülle von Möglichkeiten, Tiere zu beobachten. Wird er neu angelegt, finden sich meist schon nach wenigen Tagen die ersten Wasserwanzen, Käfer, Libellen und Amphibien ein. Eine ausgeprägte Zonierung mit Röhricht, Schwimm‐ und Tauchblattpflanzen sowie ein reich strukturiertes Umfeld mit Büschen und Steinen, die Versteck‐ und Sonnenplätze bieten, fördern die Artenvielfalt.
Microsphaerol and Seimatorone: Two New Compounds Isolated from the Endophytic Fungi, Microsphaeropsis sp. and Seimatosporium sp.
Authors: Hussain Hidayat , Root Natalia , Jabeen Farah , Al‐Harrasi Ahmed , Ahmad Manzoor , Mabood Fazal , Hassan Zahid , Shah Afzal , Green Ivan R. , Schulz Barbara , Krohn Karsten 
Published: February 2015

AbstractA new polychlorinated triphenyl diether named microsphaerol (1), has been isolated from the endophtic fungus Microsphaeropsis sp. An intensive phytochemical investigation of the endophytic fungus Seimatosporium sp., led to the isolation of a new naphthalene derivative named seimatorone (2) and eight known compounds, i.e., 1‐(2,6‐dihydroxyphenyl)‐3‐hydroxybutan‐1‐one (3), 1‐(2,6‐dihydroxyphenyl)butan‐1‐one (4), 1‐(2‐hydroxy‐6‐methoxyphenyl)butan‐1‐one (5), 5‐hydroxy‐2‐methyl‐4H‐chromen‐4‐one (6), 2,3‐dihydro‐5‐hydroxy‐2‐methyl‐4H‐chromen‐4‐one (7), 8‐methoxynaphthalen‐1‐ol (8), nodulisporins A and B (9 and 10, resp.), and daldinol (11). The structures of 1 and 2 were elucidated by detailed spectroscopic analysis including 1H‐ and 13C‐NMR, COSY, HMQC, HMBC, and HR‐EI‐MS, while the structures of the known compounds were deduced from comparison of their spectral data with those in the literature. Preliminary studies revealed that microsphaerol (1) showed good antibacterial activities against B. Megaterium and E. coli, and good antilagal and antifungal activities against C. fusca, M. violaceum, respectively. On the other hand, seimatorone (2) exhibited moderate antibacterial, antialgal, and antifungal activities.
Butane‐2,3‐dione: the Key Contributor to Axillary and Foot Odor Associated with an Acidic Note
Authors: Hara Takeshi , Kyuka Ayumi , Shimizu Hironori 
Published: February 2015

AbstractHuman body odor, which contains several volatile organic compounds, possesses various odor qualities. To identify key volatile compounds responsible for the common unpleasant odors derived from human axillae and feet, the odor quality and intensity of 118 human axillae and feet were directly evaluated by sniffing, and odor compounds obtained from the subjects were identified. Furthermore, the sensory differences in odor intensity and quality with and without addition of butane‐2,3‐dione were evaluated by using the visual analog scale (VAS). An acidic odor was a common unpleasant note in human axillae and feet. Butane‐2,3‐dione was identified as a key compound associated with this odor. Strong positive correlations between the amount of butane‐2,3‐dione, and the odor intensities of axillae and feet were observed, and the addition of butane‐2,3‐dione solution to blended short‐chain fatty‐acid solutions caused significantly increased VAS values of axillary‐like odor, unpleasantness, and odor intensity compared to those of each solution without added butane‐2,3‐dione.
Glucose Conjugation of Anti‐HIV‐1 Oligonucleotides Containing Unmethylated CpG Motifs Reduces Their Immunostimulatory Activity
Authors: Reyes‐Darias José A. , Sánchez‐Luque Francisco J. , Morales Juan Carlos , Pérez‐Rentero Sonia , Eritja Ramón , Berzal‐Herranz Alfredo 
Published: February 2015

AbstractAntisense oligodeoxynucleotides (ODNs) are short synthetic DNA polymers complementary to a target RNA sequence. They are commonly designed to halt a biological event, such as translation or splicing. ODNs are potentially useful therapeutic agents for the treatment of different human diseases. Carbohydrate–ODN conjugates have been reported to improve the cell‐specific delivery of ODNs through receptor mediated endocytosis. We tested the anti‐HIV activity and biochemical properties of the 5′‐end glucose‐conjugated GEM 91 ODN targeting the initiation codon of the gag gene of HIV‐1 RNA in cell‐based assays. The conjugation of a glucose residue significantly reduces the immunostimulatory effect without diminishing its potent anti‐HIV‐1 activity. No significant effects were observed in either ODN stability in serum, in vitro degradation of antisense DNA–RNA hybrids by RNase H, cell toxicity, cellular uptake and ability to interfere with genomic HIV‐1 dimerisation.
Construction of a Artificial Glutathione Peroxidase with Temperature‐Dependent Activity Based on a Supramolecular Graft Copolymer
Authors: Yin Yanzhen , Jiao Shufei , Wang Yun , Zhang Ruirui , Shi Zhongfeng , Hu Xiaoxi 
Published: February 2015

AbstractA supramolecular artificial glutathione peroxidase (PNIPAM‐CD‐g‐Te) was prepared based on a supramolecular graft copolymer. PNIPAM‐CD‐g‐Te was constructed by supramolecular host–guest self‐assembly. Significantly, PNIPAM‐CD‐g‐Te displayed noticeable temperature‐dependent catalytic activity and typical saturation kinetics behavior. It was also proved that the change in the self‐assembled structure of PNIPAM‐CD‐g‐Te during the temperature‐dependent process played a significant role in the temperature‐dependent catalytic behavior. The construction of PNIPAM‐CD‐g‐Te based on supramolecular graft copolymer endows artificial GPx with temperature‐dependent catalytic ability, enriched catalytic centers, and homogeneously distributed catalytic centers. This work bodes well for the development of other biologically related host–guest supramolecular biomaterials.
Structure‐Based Design of Potent Small‐Molecule Binders to the S‐Component of the ECF Transporter for Thiamine
Authors: Swier Lotteke J. Y. M. , Monjas Leticia , Guskov Albert , de Voogd Alrik R. , Erkens Guus B. , Slotboom Dirk J. , Hirsch Anna K. H. 
Published: February 2015

AbstractEnergy‐coupling factor (ECF) transporters are membrane‐protein complexes that mediate vitamin uptake in prokaryotes. They bind the substrate through the action of a specific integral membrane subunit (S‐component) and power transport by hydrolysis of ATP in the three‐subunit ECF module. Here, we have studied the binding of thiamine derivatives to ThiT, a thiamine‐specific S‐component. We designed and synthesized derivatives of thiamine that bind to ThiT with high affinity; this allowed us to evaluate the contribution of the functional groups to the binding affinity. We determined six crystal structures of ThiT in complex with our derivatives. The structure of the substrate‐binding site in ThiT remains almost unchanged despite substantial differences in affinity. This work indicates that the structural organization of the binding site is robust and suggests that substrate release, which is required for transport, requires additional changes in conformation in ThiT that might be imposed by the ECF module.
Higher‐Order Human Telomeric G‐Quadruplex DNA Metalloenzymes Enhance Enantioselectivity in the Diels–Alder Reaction
Authors: Li Yinghao , Jia Guoqing , Wang Changhao , Cheng Mingpan , Li Can 
Published: February 2015

AbstractShort human telomeric (HT) DNA sequences form single G‐quadruplex (G4) units and exhibit structure‐based stereocontrol for a series of reactions. However, for more biologically relevant higher‐order HT G4‐DNAs (beyond a single G4 unit), the catalytic performances are unknown. Here, we found that higher‐order HT G4‐DNA copper metalloenzymes (two or three G4 units) afford remarkably higher enantioselectivity (>90 % ee) and a five‐ to sixfold rate increase, compared to a single G4 unit, for the Diels–Alder reaction. Electron paramagnetic resonance (EPR) and enzymatic kinetic studies revealed that the distinct catalytic function between single and higher‐order G4‐DNA copper metalloenzymes can be attributed to different CuII coordination environments and substrate specificity. Our finding suggests that, like protein enzymes and ribozymes, higher‐order structural organization is crucial for G4‐DNA‐based catalysis.
Formation and Abundance of 5‐Hydroxymethylcytosine in RNA
Authors: Huber Sabrina M. , van Delft Pieter , Mendil Lee , Bachman Martin , Smollett Katherine , Werner Finn , Miska Eric A. , Balasubramanian Shankar 
Published: February 2015

AbstractRNA methylation is emerging as a regulatory RNA modification that could have important roles in the control and coordination of gene transcription and protein translation. Herein, we describe an in vivo isotope‐tracing methodology to demonstrate that the ribonucleoside 5‐methylcytidine (m5C) is subject to oxidative processing in mammals, forming 5‐hydroxymethylcytidine (hm5C) and 5‐formylcytidine (f5C). Furthermore, we have identified hm5C in total RNA from all three domains of life and in polyA‐enriched RNA fractions from mammalian cells. This suggests m5C oxidation is a conserved process that could have critical regulatory functions inside cells.
Elevated biomarkers and contrast‐induced acute kidney failure: What comes first the chicken or the egg?
Authors: Belardi Jorge A. , Albertal Mariano 
Published: February 2015

Key Points

Contrast‐induced acute kidney failure after primary angioplasty bears a poor short‐ and long‐term prognosis.
High baseline B‐type natriuretic peptide levels are associated with contrast‐induced acute kidney failure.
The risk of contrast‐induced acute kidney failure parallels mortality risk in patient presenting with acute myocardial infarction.
Can femoral access bleeding outcomes be improved?
Authors: Hillegass William B. , Brott Brigitta C. 
Published: February 2015

Key Points

In the absence of randomized trials, the role of vascular closure devices as a bleeding avoidance strategy compared to manual compression in ST‐elevation myocardial infarction (STEMI) patients undergoing percutaneous coronary intervention remains poorly defined.
Vascular closure devices in a propensity adjusted observational analysis were associated with one less major bleed for every 32 STEMI patients closed [95% CI: 20, 77].
Adjuncts to technique coupled with vascular closure devices may have the potential to improve femoral access safety to the level of radial access.
TAVI mixed with acute kidney injury: A recipe for increased mortality
Authors: Davidson Laura , Davidson Charles J. 
Published: February 2015

Key Points

Acute kidney injury (AKI) following Transcatheter Aortic Valve Implantation (TAVI) is a significant predictor and additive to the EuroSCORE as a determinant of TAVI mortality.
Baseline estimated glomerular filtration rate (eGFR), BMI, and major vascular bleeding are independent predictors of decline in eGFR following TAVI.
Preimplant identification of patients at high risk for AKI is mandatory. Utilization of preventive measures should include contrast minimization, staging the preprocedure evaluation, avoidance of hypotension, and minimizing vascular complications.
How to improve your “STAR quality”
Authors: Uretsky Barry F. , Carlino Mauro 
Published: February 2015

Key Points

The authors suggest that “bail‐out” STAR subintimal dissection/re‐entry technique may be improved by delaying of stenting after the initial procedure.
Deferring stenting for 2–3 months after the STAR procedure decreases the stent length and may decrease major adverse clinical outcomes.
Deferred stenting has similar incidence of target vessel revascularization as immediate stenting with the bailout STAR technique.
Safety and efficacy of a novel abluminal groove‐filled biodegradable polymer sirolimus‐eluting stent for the treatment of de novo coronary lesions: Two‐year results from a prospective patient‐level pooled analysis of TARGET trials
Authors: Gao Zhan , Zhang Ruiyan , Xu Bo , Yang Yuejin , Ma Changsheng , Li Hui , Chen Shaoliang , Han Yaling , Yuan Zuyi , Lansky Alexandra J. , Guan Changdong , Leon Martin B. , Gao Runlin ,   for the TARGET Investigators
Published: February 2015

ObjectivesWe aimed to evaluate the safety and effectiveness of the novel abluminal groove‐filled biodegradable polymer‐coated sirolimus‐eluting FIREHAWK stent (MicroPort Medical, Shanghai, China) in a large cohort of patients.BackgroundTrials on the FIREHAWK stent allowing targeted sirolimus release were not individually powered to reliably estimate low‐frequency safety endpoints such as stent thrombosis (ST) or to examine long‐term safety and efficacy. Additionally, the China Food and Drug Administration requires an objective performance criterion (OPC) study for new drug‐eluting stents. Methods: The primary endpoint, target lesion failure (TLF), was defined as the composite of cardiac death, target vessel myocardial infarction (MI), or clinically indicated target lesion revascularization at 12 months. Patient‐level data from 1,007 patients with de novo native coronary lesions exclusively treated with the FIREHAWK stent in the TARGET serial studies (I and II) were prospectively collected, pooled and analyzed throughout a 2‐year follow‐up.ResultsThe 12‐month rate of TLF in 1,003 patients (follow‐up rate, 99.6%) was 3.9% (upper 95% confidence interval (CI): 5.3%), which was significantly lower than the performance goal of 9.0% (P < 0.0001). The 24‐month rates of TLF, PoCE (a composite of all‐cause death, all MI, or any revascularization), and ARC definite or probable ST were 4.6%, 7.8% and 0.1%, respectively. In subgroup analysis, long lesion (≥30 mm) was an independent predictor of TLF within 2 years (hazard ratio [95%CI]: 2.44 [1.32, 4.53],P < 0.01).ConclusionsThis pooled, patient‐level analysis indicates that the FIREHAWK stent exhibits a promising 2‐year efficacy and safety profile. © 2015 Wiley Periodicals, Inc.
Multidisciplinary management of hypohydrotic ectodermal dysplasia – a case report
Authors: Joseph Suja , Cherackal George J. , Jacob Jose , Varghese Alex K. 
Published: February 2015

Key Clinical MessageHypohydrotic ectodermal dysplasia is a hereditary disorder, which affects ectodermal derivatives. It manifests several abnormalities of the teeth, and is commonly inherited through female carriers. This case report presents a patient with compromised esthetics and function. A multidisciplinary approach was planned involving an oral pathologist, endodontist, orthodontist and a prosthodontist.
Life‐threatening necrotizing myometritis, due to Group A streptococcus – still a life‐threatening condition
Authors: Boie Sidsel , Krog Jan , Tørring Sofus , Bor Isil Pinar 
Published: February 2015

Key Clinical MessagePuerperal infection with Group A streptococcus (GAS) can present with few symptoms and rapidly progress to a life‐threatening condition. Often, the infection can be treated with antibiotics. Delay in diagnosis increases risk of sepsis, multiorgan failure, and death. GAS infection is a differential diagnose for all postpartum women with unexplained symptoms.
Graphene‐Supported Substoichiometric Sodium Tantalate as a Methanol‐Tolerant, Non‐Noble‐Metal Catalyst for the Electroreduction of Oxygen
Authors: Sebastián David , Baglio Vincenzo , Sun Shuhui , Tavares Ana C. , Aricò Antonino S. 
Published: February 2015

AbstractFor the oxygen reduction reaction (ORR) in acidic medium, a good combination of an active and stable catalyst highly dispersed on a conductive and durable support is required. Moreover, for direct methanol fuel‐cell applications, a suitable tolerance to methanol poisoning is also necessary. In this communication, we report on a new graphene‐supported sodium tantalate (Na2Ta8O21−x) electrocatalyst obtained at high temperature and characterized by significant substoichiometry. The synthesis includes the precipitation of tantalum oxide on a high surface area graphene and subsequent thermal treatment at 900 °C. A novel sodium tantalate phase with oxygen vacancies is thereafter obtained. This catalyst formulation shows promising activity towards the ORR especially in the presence of a high methanol concentration, as evidenced by a high tolerance to methanol poisoning. Accelerated stress tests and chemical leaching experiments also show the remarkable stability of the catalyst. This material presents good perspectives for application in cost‐effective fuel cells.
A Study of the Electrochemical Properties of a New Graphitic Material: GUITAR
Authors: Gyan Isaiah O. , Wojcik Peter M. , Aston D. Eric , McIlroy David N. , Cheng I. Francis 
Published: February 2015

AbstractPrevious studies of graphite from the University of Idaho thermolyzed asphalt reaction (GUITAR) indicated two unique properties that distinguish this material from other sp2 hybridized carbon electrodes. In property i, the standard heterogeneous rate constant across the basal plane (BP) of GUITAR with Fe(CN)63−/4− of 0.01 cm s−1 was 2–7 orders of magnitude greater than for BP‐graphite and graphene. With property ii, the anodic potential limit exceeds other graphite forms by 500 mV. Two new properties are now described. In iii, the hydrogen overpotential in 1 M H2SO4 exceeds other graphitic materials by 500 mV. The combination of ii and iii gives a 3 V window in 1 M H2SO4, which is the largest reported for a graphitic material and competitive with diamond electrodes. In iv, effects of air oxidation on the edge planes (EPs) is reversed by mild cathodic reduction and does not allow for electrolyte intercalation. Based on these characteristics and on atomic force micrographs, we hypothesize that GUITAR may be a new allotrope of carbon. Coupled with expected low costs, GUITAR will find a myriad of applications in electrochemical sensors, water purification, as well as energy storage and conversion.