bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fully Enzymatic N→C‐Directed Peptide Synthesis Using C‐Terminal Peptide α‐Carboxamide to Ester Interconversion
Authors: Nuijens Timo , Piva Elena , Kruijtzer John A. W. , Rijkers Dirk T. S. , Liskamp Rob M. J. , Quaedflieg Peter J. L. M. 
Published: April 2011

AbstractChemoenzymatic peptide synthesis is potentially the most cost‐efficient technology for the synthesis of short and medium‐sized peptides with some important advantages. For instance, stoichiometric amounts of expensive coupling reagents are not required and racemisation does not occur rendering purification easier compared to chemical peptide synthesis. In this paper, a novel interconversion reaction of peptide C‐terminal α‐carboxamides into primary alkyl esters with alcalase was used to develop a fully enzymatic peptide synthesis strategy. For each elongation step a cost‐efficient amino acid carboxamide building block was used followed by the interconversion of the elongated peptide carboxamide to the corresponding primary alkyl ester. These peptide esters are the starting materials for the next enzymatic peptide elongation step.
Stereo‐Controlled Asymmetric Bioreduction of α,β‐Dehydroamino Acid Derivatives
Authors: Stueckler Clemens , Winkler Christoph K. , Hall Mélanie , Hauer Bernhard , Bonnekessel Melanie , Zangger Klaus , Faber Kurt 
Published: April 2011

Abstractα,β‐Dehydroamino acid derivatives proved to be a novel substrate class for ene‐reductases from the ‘old yellow enzyme’ (OYE) family. Whereas N‐acylamino substituents were tolerated in the α‐position, β‐analogues were generally unreactive. For aspartic acid derivatives, the stereochemical outcome of the bioreduction using OYE3 could be controlled by variation of the N‐acyl protective group to furnish the corresponding (S)‐ or (R)‐amino acid derivatives. This switch of stereopreference was explained by a change in the substrate binding, by exchange of the activating ester group, which was proven by 2H‐labelling experiments.
ASTRO‐FOLD 2.0: An enhanced framework for protein structure prediction
Authors: Subramani A. , Wei Y. , Floudas C. A. 
Published: April 2011

AbstractThe three‐dimensional (3‐D) structure prediction of proteins, given their amino acid sequence, is addressed using the first principles–based approach ASTRO‐FOLD 2.0. The key features presented are: (1) Secondary structure prediction using a novel optimization‐based consensus approach, (2) β‐sheet topology prediction using mixed‐integer linear optimization (MILP), (3) Residue‐to‐residue contact prediction using a high‐resolution distance‐dependent force field and MILP formulation, (4) Tight dihedral angle and distance bound generation for loop residues using dihedral angle clustering and non‐linear optimization (NLP), (5) 3‐D structure prediction using deterministic global optimization, stochastic conformational space annealing, and the full‐atomistic ECEPP/3 potential, (6) Near‐native structure selection using a traveling salesman problem‐based clustering approach, ICON, and (7) Improved bound generation using chemical shifts of subsets of heavy atoms, generated by SPARTA and CS23D. Computational results of ASTRO‐FOLD 2.0 on 47 blind targets of the recently concluded CASP9 experiment are presented. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Process intensification of catalytic hydrogenation of ethylanthraquinone with gas‐liquid microdispersion
Authors: Tan J. , Zhang J. S. , Lu Y. C. , Xu J. H. , Luo G. S. 
Published: April 2011

AbstractIn this article, to miniaturize the hydrogenation reactor and make the H2O2 production with more safety a gas‐liquid microdispersion system was generated to intensify the process of catalytic hydrogenation of ethylanthraquinone by passing the gas‐liquid microdispersion system through a generally packed bed reactor. A microdispersion device with a 5 μm pore size microfiltration membrane as the dispersion medium has been developed and microbubbles in the size of 10–100 μm were successfully generated. The reaction and mass transfer performance was evaluated. The conversion of ethylanthraquinone as much as 35% was realized in less than 3.5 s. The overall volume mass transfer coefficient in the microdispersion reaction system reached in the range of 1–21 s−1, more than two orders of magnitude larger than the values in normal gas‐liquid trickle‐bed reactors. A mathematical model in the form of Sh = 2.0 + 54.7Sc1/3We1/2ϕ1/10 has been firstly suggested, which can well predict the overall mass transfer coefficient. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Improved function of prototype 4.3‐mm Medtronic Quadcut microdebrider blade over standard 4.0‐mm Medtronic Tricut microdebrider blade
Authors: Boone John L. , Feldt Brent A. , McMains Kevin C. , Weitzel Erik K. 
Published: April 2011

AbstractObjectiveTest performance of a new prototype microdebrider blade. The commercially‐available, standard 4.0‐mm Medtronic straight Tricut blade was tested against the new, prototype 4.3‐mm Medtronic straight Quadcut blade in experimental surgical conditions utilizing both a nasal polyp (NP) analog (raw oysters) and an allergic fungal sinusitis (AFS) analog (minced beef cat food).MethodsBoth sides of 5 thawed, fresh‐frozen cadaver heads were utilized for NP analog removal. AFS analog was removed out of specimen containers. A total of 10 paired data points were collected for time of surgical removal and number of clogs comparing the 2 blades.ResultsFor simulated AFS debris, the prototype clogged less than the standard blade (0 vs 4.5, p < 0.0001). There were no clogs noted for either blade with the NP analog. Time for debris eradication was significantly improved for both AFS analog (147.4 vs 262.0 seconds, p < 0.0001) and NP analog (43.7 vs 112.1 seconds, p < 0.0001).ConclusionThe prototype blade offers faster debris and polyp removal and clogs less in the setting of allergic fungal debris. As the new blade is faster and more aggressive, introduction into a surgical setting should be guarded with an appropriate degree of caution. © 2011 ARS‐AAOA, LLC.
Comparative analysis of cost of endoscopic endonasal minimally invasive and sublabial‐transseptal approaches to the pituitary
Authors: Oosmanally Nadine , Paul John E. , Zanation Adam M. , Ewend Matthew G. , Senior Brent  A. , Ebert Charles S. 
Published: April 2011

AbstractBackgroundTwo surgical approaches to the pituitary are commonly used: the sublabial‐transseptal (SLTS) approach using microscopy and the endonasal endoscopic minimally invasive (MIPS) approach. Although outcomes are similar for both procedures, MIPS has become increasingly prevalent over the last 15 years. Limited cost analysis data comparing the 2 alternatives are available.MethodsA retrospective analysis of cost and volume data was performed using data from the published literature and University of North Carolina at Chapel Hill (UNC) Hospitals. A sensitivity analysis of the parameters was used to evaluate the uncertainty in parameter estimates.ResultsThe total cost in real dollars ranges from $11,438 to $12,513 and $18,095 to $21,005 per patient per procedure for MIPS and SLTS, respectively, with a cost difference ranging between $5582 and $9567 per patient per procedure. The sensitivity analysis indicates that the total cost for MIPS is most sensitive to: (1) average length of stay, (2) nursing costs, and (3) number of total complications, whereas the total cost for SLTS is most sensitive to: (1) average length of stay, (2) nursing cost, and (3) operating time. MIPS is less costly than SLTS between 94% and 98% of the time.ConclusionThe results indicate that MIPS is less costly than SLTS at a large academic center. Future research should compare the outcomes and quality of life (QoL) associated with the 2 surgeries to improve the data used to determine the cost‐effectiveness of MIPS compared to SLTS. © 2011 ARS‐AAOA, LLC.
Variability of radiation exposure with in‐office sinus computed tomography examinations
Authors: Stewart Alexander E. , Stalp John T. , Futerman Cheryl , Vaughan Winston C. 
Published: April 2011

AbstractBackgroundAn increasing number of patients seeking care by an otolaryngologist are undergoing computed tomography (CT) examinations via in‐office CT scanners. Many otolaryngologists and patients are not fully aware of the radiation dosages and the associated risks. A recent study of common CT examinations demonstrated significant variability in radiation dosages for similar studies. Despite the relatively low doses associated with sinus scans, widely publicized studies and events have generated a renewal of physician, public, and regulatory agency awareness and concern regarding medical radiation exposure.MethodsPhantom measurements and/or radiation dosage reports from CT scanners utilized by a large otolaryngology group in California were reviewed and compared. Different types of CT scanners from multiple manufacturers were included.ResultsThere was nearly a 10‐fold difference (0.15–1.45 mSv) in radiation between scans obtained from in‐office, hospital‐based, and outpatient imaging facility CT scanners.ConclusionSignificant relative variability can exist in radiation dosages associated with routine sinus CT scans obtained in different locations. There is a need for increased awareness and understanding among otolaryngologists and their patients regarding medical radiation exposure. All otolaryngologists should constantly consider the principle of “as low as reasonably achievable” (ALARA). Shielding, pediatric protocols, and other dosage reduction measures should be utilized whenever possible. © 2011 ARS‐AAOA, LLC.
Office‐based sclerotherapy for recurrent epistaxis due to hereditary hemorrhagic telangiectasia: a pilot study
Authors: Boyer Holly , Fernandes Patricia , Duran Olga , Hunter David , Goding George 
Published: April 2011

AbstractBackgroundThe aim of this pilot study is to evaluate office‐based sclerotherapy using sodium tetradecyl sulfate (STS) for epistaxis due to hereditary hemorrhagic telangiectasias (HHT). Patients with HHT suffer from unpredictable, recurrent, severe nasal bleeding necessitating emergency care, nasal packing, blood transfusions, and invasive procedures.MethodsIn this retrospective study 7 patients with a history of treatment for recurrent epistaxis due to HHT were treated in an office‐based setting with intralesional injection of STS. Treatment results were evaluated using a questionnaire. All patients had undergone multiple prior procedures attempting to control epistaxis.ResultsPatients had an average of 5 sclerotherapy treatments for HHT. Patients were treated using topical and/or local anesthesia with no reports of discomfort. Bleeding requiring intervention did not occur during the procedures. After the procedure all patients (100%) reported significantly less frequent and less severe nasal bleeding. A total of 83% reported that their need for nasal packing was reduced. All patients were willing to undergo the same treatment again. No complications such as perforation, crusting, or foul smell were reported.ConclusionThis is the first clinical experience demonstrating that office‐based sclerotherapy with STS is a safe, tolerable, and useful alternative for the treatment of epistaxis due to HHT. © 2011 ARS‐AAOA, LLC.
Sites of attachment of Schneiderian papilloma: a retrospective analysis
Authors: Schneyer Mark S. , Milam Ben M. , Payne Spencer C. 
Published: April 2011

AbstractBackgroundInverted papilloma is a benign sinonasal tumor that arises from a localized attachment site. These attachment sites, however, have not been fully characterized in the literature. The objective of this research was to determine the specific distribution of attachment sites in patients with sinonasal papilloma.MethodsRetrospective analysis of adult patients with sinonasal papilloma presenting to the University of Virginia between 1999 and 2010. These patients were reviewed and compared to historical controls with regard to histologic subtype and pedicle attachment site.ResultsA total of 83 patients were identified with 90 sites of attachment. For inverted/cylindrical papilloma, sites of attachment included the maxillary sinus (42%), ethmoid sinus (18%), nasal cavity (15%), middle/superior turbinate (12%), frontal sinus (10%), sphenoid sinus (1.5%), and cribriform plate (1.5%). Specific attachment sites within each group were identified, including 5 at the infraorbital nerve. The distribution of attachment sites differed significantly from historical controls resected via an open approach (p = 0.001), but did not differ significantly from historical controls endoscopically resected (p = 0.696). A comparison of more specific sites of attachments could not be performed due to the lack of this information in the literature.ConclusionThe distribution of attachment sites in patients with sinonasal papilloma has changed as the endoscope has enabled more detailed identification of pedicle attachment, which has implications for management. © 2011 ARS‐AAOA, LLC.
Aromatic Rings in Chemical and Biological Recognition: Energetics and Structures
Authors: Salonen Laura M. , Ellermann Manuel , Diederich François 
Published: April 2011

AbstractThis review describes a multidimensional treatment of molecular recognition phenomena involving aromatic rings in chemical and biological systems. It summarizes new results reported since the appearance of an earlier review in 2003 in host–guest chemistry, biological affinity assays and biostructural analysis, data base mining in the Cambridge Structural Database (CSD) and the Protein Data Bank (PDB), and advanced computational studies. Topics addressed are arene–arene, perfluoroarene–arene, S⋅⋅⋅aromatic, cation–π, and anion–π interactions, as well as hydrogen bonding to π systems. The generated knowledge benefits, in particular, structure‐based hit‐to‐lead development and lead optimization both in the pharmaceutical and in the crop protection industry. It equally facilitates the development of new advanced materials and supramolecular systems, and should inspire further utilization of interactions with aromatic rings to control the stereochemical outcome of synthetic transformations.
Three‐Dimensional Structure of the Nasal Passageway of a Hagfish and its Implications for Olfaction
Authors: Holmes William M. , Cotton Ross , Xuan Viet Bui , Rygg Alex D. , Craven Brent A. , Abel Richard L. , Slack Robert , Cox Jonathan P.L. 
Published: April 2011

AbstractFrom high‐resolution (65 μm) data acquired by magnetic resonance imaging, we have reconstructed the nasal passageway of a single adult hagfish specimen (probablyEptatretus stoutii). We have used this reconstruction to investigate how the anatomy and morphometry of the nasal passageway influence the olfactory ability of the hagfish. We found that the long, broad section of the passageway preceding the nasal chamber will delay the response to an odor by 1–2 s. Diffusion of odorant to the olfactory epithelium, on which the olfactory sensitivity of an animal depends, will be favored by the relatively large surface area of the olfactory epithelium (∼140 mm2) and a modest expansion in the nasal chamber. Oscillating flow (0.3–0.4 Hz) within the narrow (65–130 μm) sensory channels of the nasal chamber is laminar (Reynolds number ∼ 5) and quasi‐steady (Womersley number generally less than one). Distribution of flow over the olfactory epithelium may be aided by: (a) a narrowing before the nasal chamber; (b) partial blockage of the nasal passageway by a protrusion on the central olfactory lamella; and (c) the inward inclination of the olfactory lamellae. Anat Rec,, 2011. © 2011 Wiley‐Liss, Inc.
5‐Nitro‐2‐(3‐Phenylpropylamino) Benzoic Acid Induced Drug Resistance to Cisplatin in Human Erythroleukemia Cell Lines
Authors: Xu Ye , Zheng Hua , Kang Jin‐Song , Zhang Lei , Su Jing , Li Hong‐Yan , Sun Lian‐Kun 
Published: April 2011

AbstractMechanisms of cisplatin resistance in cancer cells are not fully understood. Here, we showed a critical role for the chloride channel‐3 (ClC‐3) in cisplatin resistance in human erythroleukemia K562 and RK562 cells. We found that a chloride channel blocker 5‐nitro‐2‐(3‐phenylpropylamino) benzoic acid (NPPB) could protect cells from cisplatin‐induced apoptosis. NPPB treatment decreased the mRNA and the protein expression of Bax/Bcl‐2, decreased the protein expressions of cytochrome C and caspase‐3, and increased the mRNA expressions of cyclin D1 and ClC‐3 in cells treated with cisplatin. The caspase‐3 activity was decreased significantly and the rate of cell apoptosis was decreased. NPPB treatment increased CIC‐3 expression, which could increase acidification of intracellular compartments, and increased sequestration of cisplatin, inducing decreased effective drug concentrations, and subsequently cell death. Collectively, our data indicate that NPPB can induce drug resistance to cisplatin by upregulating the expression of CIC‐3. NPPB‐induced CIC‐3 expression facilitates acidification of sequestrated cisplatin, and plays an important role in preventing cisplatin‐induced apoptosis in human erythroleukemia K562 and RK562 cells. Anat Rec,, 2011. © 2011 Wiley‐Liss, Inc.
Monosodium urate monohydrate crystal–recruited noninflammatory monocytes differentiate into M1‐like proinflammatory macrophages in a peritoneal murine model of gout
Authors: Martin William John , Shaw Odette , Liu Xiao , Steiger Stefanie , Harper Jacquie L. 
Published: April 2011

AbstractObjectiveTo profile monosodium urate monohydrate (MSU) crystal–recruited monocyte inflammatory function during the course of in vivo differentiation, in a murine model of peritoneal MSU crystal–induced inflammation.MethodsC57BL/6J mice were injected intraperitoneally with MSU crystals, and the peritoneal cells were harvested at different time points. The MSU crystal–recruited monocyte/macrophage population was analyzed for the expression of differentiation and activation markers, cytokine production following MSU crystal restimulation ex vivo and in vivo, expression of NLRP3‐associated proteins (ASC, caspase 1) and pro–interleukin‐1β (proIL‐1β), and phagocytic capacity.ResultsMonocytes recruited 8 hours after MSU crystal stimulation (F4/80lowGr‐1int7/4+) exhibited poor phagocytic capacity, expressed low levels of proIL‐1β, and failed to produce proinflammatory cytokines in response to MSU crystal restimulation. In the absence of MSU crystal restimulation, differentiating monocytes produced low levels of transforming growth factor β1 ex vivo, and this was abrogated following MSU crystal restimulation. Over time these cells developed a proinflammatory phenotype in vivo, characterized by the production of IL‐1β, tumor necrosis factor α, IL‐6, CCL2 (monocyte chemotactic protein 1), and CXCL1 (cytokine‐induced neutrophil chemoattractant) following ex vivo MSU crystal restimulation, and leading to IL‐1β production and cell infiltration following MSU crystal rechallenge in vivo. Proinflammatory function was associated with differentiation toward a macrophage phenotype (F4/80highGr‐1–7/4–), an increase in phagocytic capacity, and an increase in the expression of proIL‐1β.ConclusionMSU crystal–recruited monocytes differentiate into proinflammatory M1‐like macrophages in vivo. This proinflammatory macrophage phenotype is likely to play a key role in perpetuating inflammation in gouty arthritis in the presence of ongoing deposition of fresh MSU crystals.
Systemic sclerosis is an independent risk factor for increased coronary artery calcium deposition
Authors: Mok Mo Yin , Lau Chak Sing , Chiu Sonny Sau Hin , Tso Annette Wai Kwan , Lo Yi , Law Lawrence Siu Chun , Mak Ka Fung , Wong Woon Sing , Khong Peh Lan , Lam Karen Siu Ling 
Published: April 2011

AbstractObjectiveEndothelial dysfunction and inflammation are pathogenic mechanisms common to systemic sclerosis (SSc) and atherosclerosis. This study was undertaken to examine the relationship between coronary atherosclerosis, as assessed by the coronary artery calcium score (CACS), and conventional cardiovascular and disease‐specific risk factors in SSc patients.MethodsThe CACS was measured by computed tomography, and cardiovascular risk factors were examined in SSc patients and compared with controls matched for age, sex, and glycemic status. Disease activity score, antiphospholipid antibodies, high‐sensitivity C‐reactive protein level, and erythrocyte sedimentation rate were measured in SSc patients. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined.ResultsWe recruited 53 SSc patients (50 women and 3 men) and 106 controls. The patients had a mean ± SD age of 53.1 ± 12.9 years and a median disease duration of 9 years. Compared to controls, SSc patients had significantly lower low‐density lipoprotein (LDL) cholesterol levels (P = 0.001), high‐density lipoprotein cholesterol levels (P = 0.01), diastolic blood pressure, waist circumference, and body mass index and were more likely to be receiving vasodilators (all P < 0.001). There was a significantly higher proportion of SSc patients among subjects with more severe coronary calcification (CACS ≥101) compared to those with lesser severity (CACS <100) (56.5% versus 29.4%; P = 0.01). Multiple logistic regression analysis revealed SSc to be an independent determinant for a CACS ≥101 (OR 10.89 [95% CI 2.21–53.75], P = 0.003) together with age and LDL cholesterol level after adjustment for other cardiovascular risk factors. Among disease‐specific factors, only disease duration (OR 1.14 [95% CI 1.02–1.27], P = 0.02) was independently associated with more severe coronary calcification (CACS ≥101).ConclusionOur findings indicate that SSc is an independent risk factor for coronary calcification, in addition to the conventional risk factors for coronary atherosclerosis, such as age and hypertension.
Increased inflammatory cytokine expression in the vastus lateralis of patients with knee osteoarthritis
Authors: Levinger Itamar , Levinger Pazit , Trenerry Marissa K. , Feller Julian A. , Bartlett John R. , Bergman Neil , McKenna Michael J. , Cameron‐Smith David 
Published: April 2011

AbstractObjectiveIncreased inflammation and pain are inseparable parts of knee osteoarthritis (OA) that may lead to disuse of the affected limb. The aim of this study was to examine the effects of knee OA on inflammation‐ and atrophy‐related genes and proteins in the vastus lateralis muscle of patients with knee OA.MethodsNineteen patients with knee OA and 14 asymptomatic control subjects matched for age and body mass index underwent strength measurements and a muscle biopsy. Muscle was analyzed for the total cellular protein of inflammatory kinases (p65 NF‐κB, JNK1/2, STAT‐3, and suppressor of cytokine signaling 3 [SOCS‐3]) and inflammatory intracellular molecules (interleukin‐6 [IL‐6], IL‐8, monocyte chemoattractant protein 1 [MCP‐1], tumor necrosis factor α [TNFα], IL‐1β, and atrogin‐1).ResultsKnee OA resulted in greater levels of IL‐6 protein (34%; P = 0.002). The levels of inflammatory kinases, including STAT‐3 (187%; P = 0.002), p65 NF‐κB (156%; P = 0.002), and JNK1 (179%; P = 0.027), were also elevated. Furthermore, elevated expression of gene transcripts encoding MCP‐1 (28%; P = 0.023), TNFα (85%; P < 0.001), and SOCS‐3 (38%; P = 0.055) was observed in patients with knee OA compared with control subjects. Patients with knee OA had reduced muscle strength compared with control subjects (mean ± SEM 84.7 ± 8.7 versus 143.1 ± 20.8 Nm; P = 0.005). Negative correlations were observed between muscle strength and MCP‐1 protein abundance (r = −0.37 [P = 0.042]) and the gene expression of TNFα and atrogin‐1 messenger RNA (r = −0.46 [P = 0.012] and r = −0.36 [P = 0.040], respectively).ConclusionGene expression and the protein abundance of numerous muscle markers of inflammation and atrophy were elevated in patients with knee OA, and the increase in muscle inflammation was associated with a reduction in muscle strength. Given the role inflammation markers may play in muscle strength and atrophy, further studies are needed to investigate the effect of exercise intervention on skeletal muscle inflammation.