bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical Synthesis of Syndecan‐3 Glycopeptides Bearing Two Heparan Sulfate Glycan Chains
Authors: Yoshida Keisuke , Yang Bo , Yang Weizhun , Zhang Zeren , Zhang Jicheng , Huang Xuefei
Published: August 2014

Despite the ubiquitous presence of proteoglycans in mammalian systems, methodologies to synthesize this class of glycopeptides with homogeneous glycans are not well developed. Herein, we report the first synthesis of a glycosaminoglycan family glycopeptide containing two different heparan sulfate chains, namely the extracellular domain of syndecan‐3. With the large size and tremendous structural complexity of these molecules, multiple unexpected obstacles were encountered during the synthesis, including high sensitivity to base treatment and the instability of glycopeptides with two glycan chains towards catalytic hydrogenation conditions. A successful strategy was established by constructing the partially deprotected single glycan chain containing glycopeptides first, followed by union of the glycan‐bearing fragments and cleavage of the ester‐type protecting groups. This work lays the foundation for preparing other members of this important class of molecules.
One‐Pot Enzymatic Synthesis of Merochlorin A and B
Authors: Teufel Robin , Kaysser Leonard , Villaume Matthew T. , Diethelm Stefan , Carbullido Mary K. , Baran Phil S. , Moore Bradley S.
Published: August 2014

The polycycles merochlorin A and B are complex halogenated meroterpenoid natural products with significant antibacterial activities and are produced by the marine bacterium Streptomyces sp. strain CNH‐189. Heterologously produced enzymes and chemical synthesis are employed herein to fully reconstitute the merochlorin biosynthesis in vitro. The interplay of a dedicated type III polyketide synthase, a prenyl diphosphate synthase, and an aromatic prenyltransferase allow formation of a highly unusual aromatic polyketide‐terpene hybrid intermediate which features an unprecedented branched sesquiterpene moiety from isosesquilavandulyl diphosphate. As supported by in vivo experiments, this precursor is furthermore chlorinated and cyclized to merochlorin A and isomeric merochlorin B by a single vanadium‐dependent haloperoxidase, thus completing the remarkably efficient pathway.
Study of the effect of processing conditions on the co‐injection of PBS/PBAT and PTT/PBT blends for parts with increased bio‐content
Authors: Zaverl Matthew , Valerio Oscar , Misra Manjusri , Mohanty Amar
Published: August 2014

This work studies the effect of processing parameters on mechanical properties and material distribution of co‐injected polymer blends within a complex mold shape. A partially bio‐sourced blend of poly(butylene terephthalate) and poly(trimethylene terephthalate) PTT/PBT was used for the core, with a tough biodegradable blend of poly (butylene succinate) and poly (butylene adipate‐co‐terephthalate) PBS/PBAT for the skin. A ½ factorial design of experiments is used to identify significant processing parameters from skin and core melt temperatures, injection speed and pressure, and mold temperature. Interactions between the processing effects are considered, and the resulting statistical data produced accurate linear models indicating that the co‐injection of the two blends can be controlled. Impact strength of the normally brittle PTT/PBT blend is shown to increase significantly with co‐injection and variations in core to skin volume ratios to have a determining role in the overall impact strength. Scanning electron microscope images were taken of co‐injected tensile samples with the PBS/PBAT skin dissolved displaying variations of mechanical interlocking occurring between the two blends. © 2014 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41278.
Bio‐based polymeric resin from agricultural waste, neem (Azadirachta indica) seed cake, for green composites
Authors: Rahman Muhammad M. , Ho Kelly , Netravali Anil N.
Published: August 2014

Protein‐based polymeric resin has been developed from nonconventional and nonedible “neem seed cake (NSC)” that has very limited low‐value applications. Neem protein (NP), after extraction from defatted NSC, was used to prepare resin with two common plasticizers (glycerol and sorbitol). Properties of the NP resin sheets were evaluated as a function of plasticizer content. Increase of plasticizer content in NP sheets from 15 to 30% (w/w) enhanced fracture strain with a reduction in tensile strength, modulus, and thermal properties. Sorbitol‐plasticized NP sheets showed better mechanical and thermal properties in comparison to glycerol‐plasticized sheets. Effect of cross‐linking with glyoxal on the mechanical and thermal properties of sorbitol‐plasticized NP sheets was also investigated. Properties improved significantly at 10% (w/w) glyoxal content. Overall, with the enhanced properties of NP sheets, NP can be a viable alternative for edible protein‐based resin for making green composites. NP resin can also be used to replace some synthetic resins. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 10.1002/app.41291.
Polymeric PEGylated nanoparticles as drug carriers: How preparation and loading procedures influence functional properties
Authors: Gagliardi Mariacristina
Published: August 2014

The application of emerging nanotechnologies in medicine showed in the last years a significant potential in the improvement of therapies. In particular, polymeric nanocarriers are currently tested to evaluate their capability to reduce side effects, to increase the residence time in the body and also to obtain a controlled release over time. In the present work a novel polymeric nanocarrier was developed and optimized to obtain, with the same chemical formulation, three different typologies of nanocarriers: dense nanospheres loaded with an active molecule (1) during nanoparticle formation and (2) after the preparation and (3) hollow nanocapsules to increase the starting drug payload. Synthetic materials considered were PEGylated acrylic copolymers, folic acid was used as model of a hydrophobic drug. The main aim is to develop an optimized nanocarrier for the transport and the enhanced release of poorly water‐soluble drugs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41310.
Effect of dimethyl sulfoxide on synthesis of thermoplastic cellulose‐Graft‐poly(l‐lactide) copolymer using ionic liquid as reaction media
Authors: Lee Sung Jun , Lee Hae Sung , Jeong Sang Won , Kim Hyun‐Chul , Lee Se Geun , Oh Tae Hwan
Published: August 2014

In this study, ring‐opening graft polymerization of l‐lactide onto cellulose was carried out homogeneously in ionic liquid (IL)/dimethyl sulfoxide (DMSO) co‐solvent as a reaction media. Through the effective control of high viscosity and steric hindrance caused by the interaction between the IL and the hydroxyl group of cellulose by adding DMSO as a co‐solvent, cellulose‐graft‐poly(l‐lactide) (Cell‐g‐PLLA) copolymer with higher substitution efficiency was successfully prepared, at relatively low concentration of l‐lactide. The maximum values of molar substitution, degree of lactyl substitution, and degree of polymerization of poly(l‐lactide) in the copolymer were 3.76, 1.74, and 2.16, respectively, determined by 1H‐NMR. The prepared cell‐g‐PLLA copolymers showed thermal plasticization with a glass transition temperature of 155°C. In addition, the thermal processibility could be improved as the amount of grafted PLLA in the copolymer increased. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41331.
Total Syntheses of Lycoposerramine‐V and 5‐epi‐Lycoposerramine‐V
Authors: Zhang Lan‐De , Zhou Ting‐Ting , Qi Sen‐Xing , Xi Jie , Yang Xiao‐Liang , Yao Zhu‐Jun
Published: August 2014

Enantioselective total syntheses of lycopodium alkaloids lycoposerramine‐V and 5‐epi‐lycoposerramine‐V have been accomplished. Features of the newly established total synthesis include: 1) introduction of the first chiral center with a scalable desymmetrization reaction of an meso‐anhydride; 2) chemoselective functionalization of a bis‐Weinreb‐amide with Grignard addition; and 3) construction of the multifunctionalized cyclohexanone with a stereoselective intramolecular Michael addition.
The impact of price skimming on supply and exit decisions
Authors: Toptal Ayşegül , Çetinkaya Sıla
Published: August 2014

Stochastic inventory control theory has focused on the order and/or pricing policy when the length of the selling period is known. In contrast to this focus, we examine the optimal length of the selling period—which we refer to as market exit time—in the context of a novel inventory replenishment problem faced by a supplier of a new, trendy, and relatively expensive product with a short life cycle. An important characteristic of the problem is that the supplier applies a price skimming strategy over time and the demand is modeled as a nonhomogeneous Poisson process with an intensity that is dependent on time. The supplier's problems of finding the optimal order quantity and market exit time, with the objective of maximizing expected profit, is studied. Procedures are proposed for joint optimization of the objective function with respect to the order quantity and the market exit time. Then, the effects of the order quantity and market exit time on the supplier's profitability are explored on the basis of a quantitative investigation. Copyright © 2014 John Wiley & Sons, Ltd.
Untargeted metabolite profiling of murine embryos to reveal metabolic perturbations associated with neural tube closure defects
Authors: Hansler Alex , Chen Qiuying , Gray Jason D. , Ross M. Elizabeth , Finnell Richard H. , Gross Steven S.
Published: August 2014

Background

Neural tube closure defects (NTDs) are among the most common congenital malformation in human, typically presenting in liveborns as spina bifida. At least 240 gene mutations in mouse are known to increase the risk of NTD. There is a growing appreciation that environmental factors significantly contribute to NTD expression, and that NTDs likely arise from complex gene‐environment interactions. Because maternal folic acid supplementation reduces human NTD risk in some populations by 60 to 70%, it is likely that NTD predisposition is often associated with a defect in folate‐dependent one‐carbon metabolism. A comprehensive, untargeted metabolic survey of NTD‐associated changes in embryo metabolism would provide a valuable test of this assumption. We sought to establish a metabolic profiling platform that is capable of broadly assessing metabolic aberrations associated with NTD‐promoting gene mutations in early‐stage mouse embryos.

Methods

A liquid chromatography/mass spectrometry‐based untargeted metabolite profiling platform was used to broadly identify significant differences in small molecule levels (50–1000 Da) in NTD‐affected embryonic day (E) 9.5 mouse embryos (Lrp6−/−) versus unaffected (Lrp6+/+) control embryos.

Results

Results provide proof‐of‐principal feasibility for the broad survey of the metabolome of individual E9.5 mouse embryos and identification of metabolic changes associated with NTDs and gene mutations. Levels of 30 different metabolites were altered in association with Lrp6 gene deletion. Some metabolites link to folate‐dependent one‐carbon transfer reactions, as anticipated, while others await structure elucidation and pathway integration.

Conclusion

Whole‐embryo metabolomics offers the potential to identify metabolic changes in genetically determined NTD‐prone embryos. Birth Defects Research (Part A) 100:623–632, 2014. © 2014 Wiley Periodicals, Inc.
Sensitive determination of carbidopa through the electrochemiluminescence of luminol at graphene‐modified electrodes
Authors: Hosseini Morteza , Mirzanasiri Nooshin , Rezapour Morteza , Sheikhha Mohammad Hasan , Faridbod Farnoush , Norouzi Parviz , Ganjali Mohammad Reza
Published: August 2014

Using the concept of electrogenerated chemiluminescence (ECL), a sensitive analytical method for the determination of carbidopa is described. Electro‐oxidation of carbidopa on the surface of a graphene oxide (GO)‐modified gold electrode (GE) leads to enhancement of the weak emission of oxidized luminol. Under optimum experimental conditions, the ECL signal increases linearly with increasing carbidopa concentrations over a range of 1.0 × 10‐9–1.7 × 10‐7 M, with a detection limit of 7.4 × 10‐10 M. The proposed ECL method was successfully used for the determination of carbidopa in urine samples. Copyright © 2014 John Wiley & Sons, Ltd.
Synergistic effect of Aspergillus niger and Trichoderma reesei enzyme sets on the saccharification of wheat straw and sugarcane bagasse
Authors: van den Brink Joost , Maitan‐Alfenas Gabriela Piccolo , Zou Gen , Wang Chengshu , Zhou Zhihua , Guimarães Valéria Monteze , de Vries Ronald P.
Published: August 2014

Plant‐degrading enzymes can be produced by fungi on abundantly available low‐cost plant biomass. However, enzymes sets after growth on complex substrates need to be better understood, especially with emphasis on differences between fungal species and the influence of inhibitory compounds in plant substrates, such as monosaccharides. In this study, Aspergillus niger and Trichoderma reesei were evaluated for the production of enzyme sets after growth on two “second generation” substrates: wheat straw (WS) and sugarcane bagasse (SCB). A. niger and T. reesei produced different sets of (hemi‐)cellulolytic enzymes after growth on WS and SCB. This was reflected in an overall strong synergistic effect in releasing sugars during saccharification using A. niger and T. reesei enzyme sets. T. reesei produced less hydrolytic enzymes after growth on non‐washed SCB. The sensitivity to non‐washed plant substrates was not reduced by using CreA/Cre1 mutants of T. reesei and A. niger with a defective carbon catabolite repression. The importance of removing monosaccharides for producing enzymes was further underlined by the decrease in hydrolytic activities with increased glucose concentrations in WS media. This study showed the importance of removing monosaccharides from the enzyme production media and combining T. reesei and A. niger enzyme sets to improve plant biomass saccharification.
Biocatalytic coatings for air pollution control: A proof of concept study on VOC biodegradation
Authors: Estrada José M. , Bernal Oscar I. , Flickinger Michael C. , Muñoz Raúl , Deshusses Marc A.
Published: August 2014

Although biofilm‐based biotechnologies exhibit a large potential as solutions for off‐gas treatment, the high water content of biofilms often causes pollutant mass transfer limitations, which ultimately limit their widespread application. The present study reports on the proof of concept of the applicability of bioactive latex coatings for air pollution control. Toluene vapors served as a model volatile organic compound (VOC). The results showed that Pseudomonas putida F1 cells could be successfully entrapped in nanoporous latex coatings while preserving their toluene degradation activity. Bioactive latex coatings exhibited toluene specific biodegradation rates 10 times higher than agarose‐based biofilms, because the thin coatings were less subject to diffusional mass transfer limitations. Drying and pollutant starvation were identified as key factors inducing a gradual deterioration of the biodegradation capacity in these innovative coatings. This study constitutes the first application of bioactive latex coatings for VOC abatement. These coatings could become promising means for air pollution control. Biotechnol. Bioeng. 2015;112: 263–271. © 2014 Wiley Periodicals, Inc.
Multiple approaches to predicting oxygen and glucose consumptions by HepG2 cells on porous scaffolds in an axial‐flow bioreactor
Authors: Podichetty Jagdeep T. , Bhaskar Prasana R. , Singarapu Kumar , Madihally Sundararajan V.
Published: August 2014

In this study, the distribution of oxygen and glucose was evaluated along with consumption by hepatocytes using three different approaches. The methods include (i) Computational Fluid Dynamics (CFD) simulation, (ii) residence time distribution (RTD) analysis using a step‐input coupled with segregation model or dispersion model, and (iii) experimentally determined consumption by HepG2 cells in an open‐loop. Chitosan‐gelatin (CG) scaffolds prepared by freeze‐drying and polycaprolactone (PCL) scaffolds prepared by salt leaching technique were utilized for RTD analyses. The scaffold characteristics were used in CFD simulations i.e. Brinkman's equation for flow through porous medium, structural mechanics for fluid induced scaffold deformation, and advection‐diffusion equation coupled with Michaelis–Menten rate equations for nutrient consumption. With the assumption that each hepatocyte behaves like a micro‐batch reactor within the scaffold, segregation model was combined with RTD to determine exit concentration. A flow rate of 1 mL/min was used in the bioreactor seeded with 0.6 × 106 HepG2 cells/cm3 on CG scaffolds and oxygen consumption was measured using two flow‐through electrodes located at the inlet and outlet. Glucose in the spent growth medium was also analyzed. RTD results showed distribution of nutrients to depend on the surface characteristics of scaffolds. Comparisons of outlet oxygen concentrations between the simulation results, and experimental results showed good agreement with the dispersion model. Outlet oxygen concentrations from segregation model predictions were lower. Doubling the cell density showed a need for increasing the flow rate in CFD simulations. This integrated approach provide a useful strategy in designing bioreactors and monitoring tissue regeneration. Biotechnol. Bioeng. 2015;112: 393–404. © 2014 Wiley Periodicals, Inc.
Enhanced production of fatty alcohols by engineering the TAGs synthesis pathway in Saccharomyces cerevisiae
Authors: Tang Xiaoling , Chen Wei Ning
Published: August 2014

The production of fatty acid‐derived chemicals has received a great deal of attention in recent years. In yeast cells, the main storage forms of fatty acids are TAGs. However, the conversion of TAGs into fatty acid derivatives suffers from a practical standpoint. Herein, a more direct strategy was applied to accumulate cellular fatty acyl‐CoAs in Saccharomyces cerevisiae, which are the activated forms of fatty acids and used as important precursors for various converting enzymes. The dga1 gene was deleted to block the fatty acyl‐CoAs dependent pathway of TAGs synthesis and a significant decrease in lipid content was observed. The FAR gene was cloned and overexpressed in the wild type strain and gene disrupted strain, to convert the fatty acyl‐CoAs to the corresponding fatty acid derivatives. The metabolic engineered pathway resulted in enhanced production of fatty alcohols. Compared with the wild type strain with overexpressed FAR gene, the yield of fatty alcohols in the Δdga1 strain with FAR was dramatically increased: the intracellular fatty alcohols increased from 26 mg/L to 45 mg/L, while the extracellular fatty alcohols increased from 2.2 mg/L to 4.3 mg/L. By optimizing the culture medium with increased carbon concentration and limited nitrogen concentration, the fatty alcohols yield in the Δdga1 strain with FAR was further increased to 84 mg/L in cells and 14 mg/L secreted in broth. The results in this study demonstrated the feasibility of using the designed strategy to solve the bottleneck in utilizing TAGs for fatty acid derivatives production. Biotechnol. Bioeng. 2015;112: 386–392. © 2014 Wiley Periodicals, Inc.
Production of recombinant proteins in microalgae at pilot greenhouse scale
Authors: Gimpel Javier A. , Hyun James S. , Schoepp Nathan G. , Mayfield Stephen P.
Published: August 2014

Recombinant protein production in microalgae chloroplasts can provide correctly folded proteins in significant quantities and potentially inexpensive costs compared to other heterologous protein production platforms. The best results have been achieved by using the psbA promoter and 5′ untranslated region (UTR) to drive the expression of heterologous genes in a psbA‐deficient, non‐photosynthetic, algal host. Unfortunately, using such a strategy makes the system unviable for large scale cultivation using natural sunlight for photosynthetic growth. In this study we characterized eight different combinations of 5′ regulatory regions and psbA coding sequences for their ability to restore photosynthesis in a psbA‐deficient Chlamydomonas reinhardtii, while maintaining robust accumulation of a commercially viable recombinant protein driven by the psbA promoter/5′UTR. The recombinant protein corresponded to bovine Milk Amyloid A (MAA), which is present in milk colostrum and could be used to prevent infectious diarrhea in mammals. This approach allowed us to identify photosynthetic strains that achieved constitutive production of MAA when grown photosynthetically in 100 L bags in a greenhouse. Under these conditions, the maximum MAA expression achieved was 1.86% of total protein, which corresponded to 3.28 mg/L of culture medium. Within our knowledge, this is the first report of a recombinant protein being produced this way in microalgae. Biotechnol. Bioeng. 2015;112: 339–345. © 2014 Wiley Periodicals, Inc.
Factors Associated with Recommitment of NGRI Acquittees to a Forensic Hospital
Authors: Green Debbie , Belfi Brian , Griswold Hali , Schreiber Jeremy M. , Prentky Robert , Kunz Michal
Published: August 2014

The current archival study assesses risk factors associated with recommitment of 142 individuals adjudicated Not Guilty by Reason of Insanity (NGRI) from civil settings to a forensic hospital in New York State. Within 10 years of transfer from a forensic hospital, 40 (28.2%) were recommitted. Using survival analyses to account for the wide range in opportunity for recommitment, period of transfer (i.e., pre versus post the 1995 case of George L, which clarified factors related to assessments of dangerousness) and the Historical scale and specific items of the HCR‐20 emerged as important risk factors for recommitment. Specifically, hazard of recommitment was 2.9 times higher for those with high Historical scores as compared to those with low scores. However, few individual risk factors were associated with recommitment. Prior supervision failure, negative attitude, problems with substance use, and absent or less serious major mental illness and relationship problems were informative in predicting recommitment over 10 and 3 year follow‐up periods. Copyright © 2014 John Wiley & Sons, Ltd.
One‐year outcome from an all‐comers population of patients with ST‐segment elevation myocardial infarction treated with biolimus‐eluting stent with biodegradable polymer
Authors: Tomai Fabrizio , De Luca Leonardo , Altamura Luca , Versaci Francesco , Pennacchi Mauro , Proietti Igino , Ghini Anna S. , Corvo Pierfrancesco , De Persio Giovanni , Petrolini Alessandro , Tommasino Antonella , Sardella Gennaro
Published: August 2014

Objectives

To evaluate the performance of biolimus‐eluting stent (BES) in patients with ST‐elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) in a real world clinical scenario.

Background

Randomized studies suggest that the BES with biodegradable polymer is more effective and safe than early generation coronary stents in patients with STEMI.

Methods

We included all consecutive STEMI patients undergoing PCI in this prospective, multicenter registry. The primary endpoint of the study was the rate of major adverse cardiac events (MACE), a composite of cardiac death, recurrent myocardial infarction and ischemia‐driven target vessel revascularization at 1‐year follow‐up.

Results

Between June and December 2012 we enrolled 311 STEMI patients. The primary endpoint occurred in 3.2% (95% confidence interval: 1.6–5.8) of patients: cardiac death, re‐infarction, and ischemia‐driven TVR occurred in 2.3%, 1.3%, and 0.6% of patients, respectively. One‐year MACE‐free survival was 96.8% ± 1.0%.

Conclusions

In a real‐world cohort of STEMI patients undergoing PCI, the use of BES is associated with good 1‐year clinical outcome. These results confirm and expand previous findings showing the efficacy and safety of BES in the setting of randomized trials. © 2014 Wiley Periodicals, Inc.
Serial intravascular ultrasound analysis of complex bifurcation coronary lesions treated with the tryton bifurcation stent in conjunction with an everolimus‐eluting stent: IUVANT (Intravascular ultrasound evaluation of tryton stent) study
Authors: Bartorelli Antonio L. , Trabattoni Daniela , Almonacid Alexandra , Fabbiocchi Franco , Montorsi Piero , Galli Stefano , Grancini Luca , Ravagnani Paolo , Mintz Gary S. , Kaplan Aaron V. , Popma Jeffrey J. , Maehara Akiko
Published: August 2014

Objectives

To characterize the treatment of complex bifurcation lesions (BL) with the Tryton Bifurcation Stent (TBS) paired with an everolimus‐eluting stent (EES).

Background

Complex BL are associated with higher procedural complications and poorer long‐term outcomes. The TBS is a dedicated side‐branch (SB) stent designed to be used in conjunction with a standard drug‐eluting stent.

Methods

Prospectively identified, consecutive patients underwent TBS+EES stenting of BL using a protocol which included TBS postdilation and simultaneous final kissing balloon inflations (FKBI). All lesions were systematically evaluated with coronary angiography and IVUS, obtained at procedure completion and at 9 months, and were assessed by independent core laboratories.

Results

Thirty‐three BL were treated in 32 patients presenting primarily (87.5%) with stable angina and complex BL with angiographic apparent disease in the main vessel (MV) and SB in 87.9% and 75% by site and core evaluation, respectively. Procedural success was 100% and high postprocedure percent stent expansion (MV 96 [93, 109]%, SB 88 [77, 100]%, carina MV 135 [99, 166]%, carina SB 116 [91, 130]%) was demonstrated by IVUS. At 9‐month angiographic follow‐up (n = 28 patients), one MV in‐segment restenosis and one SB in‐stent restenosis were observed. SB in‐stent late lumen loss was 0.41 ± 0.27 mm. IVUS assessment revealed the absence of stent recoil; percent carinal neointimal hyperplasia (NIH) was 1.8 [0.0,11.2]% in MV and 15.0 [6.7,23.5]% in SB, with NIH volume obstruction of 2.0 [0.7,4.3]% in MV and 14.2 [7.5,29.6]% in SB.

Conclusions

Stenting of complex BL with the TBS+EES provides high acute success with sustained clinical, angiographic, and IVUS results at 9 months. These excellent results are likely due to the extent of stent expansion at the carina. © 2014 Wiley Periodicals, Inc.
Sex‐based differences in bleeding and long term adverse events after percutaneous coronary intervention for acute myocardial infarction: Three year results from the HORIZONS‐AMI trial
Authors: Yu Jennifer , Mehran Roxana , Grinfeld Liliana , Xu Ke , Nikolsky Eugenia , Brodie Bruce R. , Witzenbichler Bernhard , Kornowski Ran , Dangas George D. , Lansky Alexandra J. , Stone Gregg W.
Published: August 2014

Background

Studies have shown sex‐based disparities in ST‐segment elevation myocardial infarction (STEMI) management and prognosis. We sought to compare women and men undergoing primary percutaneous coronary intervention (PCI) for STEMI in a large, prospective, contemporary context.

Methods

The Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS‐AMI) trial randomized 3,602 patients (23.4% women and 76.6% men) with STEMI presenting within 12 hr of onset of symptoms to bivalirudin or heparin plus glycoprotein IIb/IIIa inhibitors and to PCI with drug‐eluting or bare metal stents.

Results

Compared with men, women presented later after symptom onset and were more often treated with medical management alone (6.9% vs. 4.7%; P = 0.01). Women had significantly higher rates of 3‐year major adverse cardiac events (MACE) and major bleeding. After adjusting for baseline differences, female sex remained an independent predictor of major bleeding (hazard ratio [HR] 1.81, 95% confidence interval [CI] 1.41–2.33; P < 0.0001) but not of MACE (HR 1.09; 95% CI 0.91–1.32; P = 0.35).

Conclusions

This study found that women with STEMI are at increased risk of bleeding as compared to men. While female sex may not directly contribute to increased risk of MACE, it is, however, associated with the presence of comorbidities that increase the risk of ischemic events long‐term. Further dedicated studies are needed to confirm these findings and to assess strategies to optimize both the initial emergent treatment and long‐term management in this high‐risk subset. © 2014 Wiley Periodicals, Inc.
Pushing with the pigtail: A novel approach to placing the MitraClip in a patient with a severely restricted posterior mitral leaflet
Authors: Jones Brandon M. , Tuzcu E. Murat , Kapadia Samir R.
Published: August 2014

The MitraClip is an US Food and Drug Administration‐approved device for inoperable patients with severe degenerative mitral regurgitation (MR) and is under investigation for use in patients with severe functional MR. Simultaneously grasping both leaflets of the mitral valve can be technically challenging, however, in patients with a restricted posterior leaflet. We present one such case in which a pigtail catheter, placed retrograde into the left ventricle, was able to push the ventricular surface of the posterior leaflet into closer approximation with the anterior leaflet, and facilitate successful clip placement. We provide this report in hopes that it will provide a useful strategy for interventionalists faced with this challenging situation. © 2014 Wiley Periodicals, Inc.
Commentary on highlighted late breaking trials in interventional cardiology at ESC, VIVA, TCT, and AHA 2013
Authors: Tremmel Jennifer A. , Patel Rajan A.G. , Bhatt Deepak L. , Cilingiroglu Mehmet , Pinto Duane S. , Dean Larry S. , Grines Cindy L.
Published: August 2014

With the plethora of clinical trials, it is difficult for busy interventional cardiologists to stay up to date. Therefore, the SCAI publications committee concisely summarizes and provides editorial commentary on the most important trials from recent, large international meetings. The intent is to provide this summary every six months to allow quick assimilation of trial results into interventional practice. © 2014 Wiley Periodicals, Inc.
Liquid‐Solid Mass Transfer Behavior of a Stirred‐Tank Reactor with a Fixed Bed at Its Bottom
Authors: El‐Naggar Mohamed A. , Abdel‐Aziz Mohamed H. , Zatout Ahmed A. , Sedahmed Gomaa H.
Published: August 2014

The mass transfer behavior of a new batch stirred tank with a fixed bed of Raschig rings at the bottom was studied using diffusion‐controlled dissolution of copper in acidified dichromate. Variables studied, amongst others, were the impeller rotation speed, Raschig ring diameter, fixed‐bed height, and impeller geometry. The rate of mass transfer from the fixed bed to the solution increased with increasing impeller rotation speed, decreasing particle size, and decreasing bed height. The axial‐flow turbine is more efficient in increasing the rate of mass transfer than the radial‐flow turbine. The presented reactor is especially useful for conducting diffusion‐controlled liquid‐solid catalytic reactions involving reactants that need to be dispersed first, such as sparingly soluble solid particles.
Design and Control of an Integrated 1,4‐Butanediol Dehydrogenation and Furfural Hydrogenation Plant
Authors: Javaid Ahtesham , Bildea Costin S.
Published: August 2014

The design and plantwide control of an integrated plant, where the endothermic dehydrogenation of 1,4‐butanediol leading to γ‐butyrolactone and the exothermic hydrogenation of furfural leading to furfural alcohol and 2‐methyl furan are simultaneously performed in a single reactor, is presented. Analysis of the reactor‐separation‐recycle system shows that the reactions can be carried out using small hydrogen excess, in an adiabatic reactor, with reduced parameter sensitivity. The plant is flexible, allowing different production rates and a wide range of ratios between the furfural alcohol and 2‐methyl furan products. The additional separation of γ‐butyrolactone from the reaction mixture is easy. The conclusions are supported by rigorous steady‐state and dynamic simulations performed in AspenPlus and AspenDynamics.
Estimation of rotation ambiguity in multivariate curve resolution with charged particle swarm optimization (cPSO‐MCR)
Authors: Skvortsov Alexey N.
Published: August 2014

Rotation ambiguity (RA) in multivariate curve resolution (MCR) is an undesirable case, when the physicochemical constraints are not sufficiently strong to provide a unique resolution of the data matrix of the mixtures into spectra and concentration profiles of individual chemical components. RA is often met in MCR of overlapped chromatographic peaks, kinetic and equilibrium data, and fluorescence two‐dimensional spectra. In case of RA, a single candidate solution has little practical value. So, the whole set of feasible solutions should be characterized somehow. It is a quite intricate task in a general case.

In the present paper, a method was proposed to estimate RA with charged particle swarm optimization (cPSO), a population‐based algorithm. The criteria for updating the particles were modified, so that the swarm converged to the steady state, which spanned the set of feasible solutions. The performance of cPSO‐MCR was demonstrated on test functions, simulated datasets, and real‐world data. Good accordance of the cPSO‐MCR results with the analytical solutions (Borgen plots) was observed. cPSO‐MCR was also shown to be capable of estimating the strength of the constraints and of revealing RA in noisy data.

As compared with analytical methods, cPSO‐MCR is simpler to implement, expands to more than three chemical compounds, is immune to noise, and can be easily adapted to virtually all types of constraints and objective functions (constraint based or residue based). cPSO‐MCR also provides natural visual information about the level of RA in spectra and concentration profiles, similar to the methods of two extreme solutions (e.g., MCR‐BANDS). Copyright © 2014 John Wiley & Sons, Ltd.
Conformational and H‐Bonding Preferences for Facile Racemate Crystallization of Ribose
Authors: Patyk Ewa , Katrusiak Andrzej
Published: August 2014

Recalcitrant crystallization and syrup formation are frequent features of natural sugars. This is the case of d‐ribose, yielding low‐quality crystals of mixed α‐ and β‐pyranose anomers. However, large crystals of dl‐ribose can be grown easily. The crystal structures of stable d‐ribose forms I and II as well as dl‐form II have been analyzed in terms of their compatibility with the molecular aggregation. The comparison of the potential energy of all conformers and their OH···O hydrogen‐bonding patterns is consistent with the preferential racemate crystallization in terms of departures from the optimized isolated ribose molecule and its directional interactions. This analysis is aimed at rationalizing the interplay between the molecular structure and spontaneous crystallization of chiral compounds. Chirality 26: 806–810, 2014. © 2014 Wiley Periodicals, Inc.
Magnetic Circular Dichroism of Porphyrin Lanthanide M3+ Complexes
Authors: Andrushchenko Valery , Padula Daniele , Zhivotova Elena , Yamamoto Shigeki , Bouř Petr
Published: August 2014

Lanthanide complexes exhibit interesting spectroscopic properties yielding many applications as imaging probes, natural chirality amplifiers, and therapeutic agents. However, many properties are not fully understood yet. Therefore, we applied magnetic circular dichroism (MCD) spectroscopy, which provides enhanced information about the underlying electronic structure to a series of lanthanide compounds. The metals in the M3+ state included Y, La, Eu, Tb, Dy, Ho, Er, Tm, Yb, and Lu; the spectra were collected for selected tetraphenylporphin (TPP) and octaethylporphin (OEP) complexes in chloroform. While the MCD and UV‐VIS absorption spectra were dominated by the porphyrin signal, metal binding significantly modulated them. MCD spectroscopy was found to be better suited to discriminate between various species than absorption spectroscopy alone. The main features and trends in the lanthanide series observed in MCD and absorption spectra of the complexes could be interpreted at the Density Functional Theory (DFT) level, with effective core potentials on metal nuclei. The sum over state (SOS) method was used for simulation of the MCD intensities. The combination of the spectroscopy and quantum‐chemical computations is important for understanding the interactions of the metals with the organic compounds. Chirality 26:655–662, 2014. © 2014 Wiley Periodicals, Inc.
Modelling and simulation of raw material blending process in cement raw mix milling installations
Authors: Tsamatsoulis Dimitris
Published: August 2014

A series of multivariable models composed from linear differential equations, integrals, and delays has been developed to describe the dynamics of mixing of the raw materials during the cement raw meal milling. The dynamics between the main oxides and chemical modules of raw mix in mill outlet and the materials proportions in mill entrance is investigated. The distributions of model parameters (gains, time constants, delays, steady state values) are determined. In this way, the structure of the parameters' uncertainty is clearly expressed, explained by the raw materials composition uncertainty and can be used in process simulation. A successful attempt is made to simulate the mill operation by including the main components of the process concerning mixing and dynamics. The simulator calculates the chemical analyses and modules of raw meal in the mill outlet, and also the dynamics of the main module characterizing raw meal and cement i.e., the lime saturation factor (LSF). Thus, the effect of the raw materials compositions and their uncertainty on LSF dynamics is studied. The dynamical models analyzed can be used to build robust controllers, while the simulator constitutes a tool to evaluate the efficiency of the control strategies.
On the analysis of ionic mass transfer in the electrolytic bath of an aluminum reduction cell
Authors: Ariana Mohsen , Désilets Martin , Proulx Pierre
Published: August 2014

An electrolyte typically used in an aluminum electrolysis cell is composed of different ions moving in the electromagnetic field generated by the high intensity current needed for the industrial application. The flux of these ions has an important impact on the functional parameters of the cell, like current efficiency. In this study, the transient behaviour of these ions in the NaF‐AlF3‐Al2O3 mixture is modelled using a numerical finite element method. The electric potential field equation governed by electrochemical reaction kinetics at electrodes is solved to obtain the electric potential field, current density, and consequently heat generation in the cell. Subsequently, the concentration field is solved for ionic species in the bath. The results indicate formation of a high concentration gradient of electroactive ions like Al2OF62− and AlF4− at the corresponding reacting electrodes with time and diffusion as the main mechanism for these ions transfer. It is found that from the early stages of the 3 minute simulation of the electrochemical process, the difference between bulk concentration and surface concentration of electroactive ions remains constant. Moreover, the results indicate that although the flux of electroactive species is dominated by diffusion, especially for larger times, migration is the controlling mechanism of transport for the electroinactive ions.
Viscosities and densities of systems containing fatty compounds and alcoholic solvents
Authors: Granero Maira G. , Rocha Bruna B. , Chaves Matheus A. , Brasil Fernanda C. G. , Aracava Keila K. , Rodrigues Christianne E. C. , Ceriani Roberta , Gonçalves Cintia B.
Published: August 2014

This work presents viscosities and densities of systems composed of vegetable oils (or animal fat), commercial fatty acids, ethanol, and water at several temperatures. These systems are of great importance for oil/fat deacidification by liquid‐liquid extraction (LLE) using aqueous ethanol as solvent, as well as for ethylic biodiesel production. Experimental data and accurate predictive models of physical properties, such as viscosity and density, are essential for process designers mainly because they affect fluid dynamics, coefficients of heat and mass transfer, and consequently column efficiency. Experimental data for viscosities were also estimated using well‐known methods, such as Kay's mixing rules (simple and modified form) and GC‐UNIMOD. Despite the non‐ideality inherent to the mixtures studied in this work, approximately 71 % of the systems showed an acceptable estimation of their viscosities using at least one of these three models, with average relative deviations (ARD) up to 10 %. A simple mixing rule, based on densities of pure compounds and their mass fractions in the mixture, was used for estimating densities with ARD values not higher than 0.54 %.
Lessons from early clinical experience with the Afirma gene expression classifier
Authors: Krane Jeffrey F.
Published: August 2014

Early clinical experience with the Afirma gene expression classifier indicates potential limitations of the test in everyday practice. The Afirma test may have diminished utility for Hurthle cell lesions. Additional challenges include high test cost relative to repeat fine needle aspiration and the dependence of test performance on highly variable diagnostic thresholds in cytology and surgical pathology specimens.
Thyroid nodules with KRAS mutations are different from nodules with NRAS and HRAS mutations with regard to cytopathologic and histopathologic outcome characteristics
Authors: Radkay Lisa A. , Chiosea Simion I. , Seethala Raja R. , Hodak Steven P. , LeBeau Shane O. , Yip Linwah , McCoy Kelly L. , Carty Sally E. , Schoedel Karen E. , Nikiforova Marina N. , Nikiforov Yuri E. , Ohori N. Paul
Published: August 2014

BACKGROUND

Mutations in the RAS gene in the thyroid gland result in the activation of signaling pathways and are associated with a follicular growth pattern and the probability of a carcinoma outcome ranging from 74% to 87%. In the current study, the authors investigated the cytopathologic and histopathologic features of common RAS mutation subtypes.

METHODS

Malignant, indeterminate, and selected benign thyroid cytology cases were tested prospectively for the presence of NRAS61, HRAS61, and KRAS12/13 mutations. For each case, the Bethesda System for thyroid cytopathology diagnosis, additional cytologic descriptors, and surgical pathology outcomes were documented. The Fisher exact test and Wilcoxon 2‐sample test were used for statistical comparison between the groups.

RESULTS

A total of 204 thyroid fine‐needle aspiration cases with RAS mutations (93.6% of which were associated with indeterminate cytopathology diagnoses) and corresponding surgical pathology resection specimens were identified. The KRAS12/13 mutation was associated with a significantly lower carcinoma outcome (41.7%) when compared with HRAS61 (95.5%) and NRAS61 (86.8%) mutations (P<.0001). Furthermore, oncocytic change was observed in a significantly higher percentage of cytology and resection specimens with KRAS12/13 mutations (66.7% and 75.0%, respectively) in comparison with those with HRAS61 (4.5% and 4.5%, respectively) and NRAS61 (15.4% and 14.7%, respectively) mutations (P<.0001). RAS mutations also were identified in cases of poorly differentiated carcinoma (NRAS61), anaplastic carcinoma (HRAS61), and medullary thyroid carcinoma (HRAS61 and KRAS12/13).

CONCLUSIONS

Subclassification of RAS mutations in conjunction with cytopathologic evaluation improves presurgical risk stratification, provides better insight into lesional characteristics, and may influence patient management. In particular, KRAS12/13‐mutated thyroid nodules were found to be different from HRAS61‐mutated and NRAS61‐mutated nodules with regard to cytopathologic and surgical outcome characteristics. Cancer (Cancer Cytopathol) 2014;122:873–882. © 2014 American Cancer Society.
Recycling of Carbon Dioxide and Acetate as Lactic Acid by the Hydrogen‐Producing Bacterium Thermotoga neapolitana
Authors: d'Ippolito Giuliana , Dipasquale Laura , Fontana Angelo
Published: August 2014

The heterotrophic bacterium Thermotoga neapolitana produces hydrogen by fermentation of sugars. Under capnophilic (carbon dioxide requiring) conditions, the process is preferentially associated with the production of lactic acid, which, as shown herein, is synthesized by reductive carboxylation of acetyl coenzyme A. The enzymatic coupling is dependent on the carbon dioxide stimulated activity of heterotetrameric pyruvate:ferredoxin oxidoreductase. Under the same culture conditions, T. neapolitana also operates the unfavorable synthesis of lactic acid from an exogenous acetate supply. This process, which requires carbon dioxide (or carbonate) and an unknown electron donor, allows for the conversion of carbon dioxide into added‐value chemicals without biomass deconstruction.
Maximum likelihood estimation of FRET efficiency and its implications for distortions in pixelwise calculation of FRET in microscopy
Authors: Nagy Peter , Szabó Ágnes , Váradi Tímea , Kovács Tamás , Batta Gyula , Szöllősi János
Published: August 2014

Ratiometric determination of the efficiency of fluorescence or Förster resonance energy transfer (FRET) is one of the most widespread methods for the characterization of protein clustering and conformation. Low photon numbers, often present in pixel‐by‐pixel determination of FRET efficiency in digital microscopy, result in large uncertainties in the derived FRET parameter. Here, we propose a method based on maximum likelihood estimation (MLE) of FRET efficiency using photon counting detectors to overcome this limitation. Intensities measured in the donor, FRET, and acceptor channels were all assumed to follow Poisson statistics as a result of detector shot noise. The joint probability of photon numbers detected in the donor, FRET, and acceptor channels was derived using an equation describing the relationship between the three measured intensities. The FRET efficiency generating the measured photon numbers with the largest likelihood was determined iteratively providing a single FRET value for all pixels in the calculation. Since as few as 100 pixels are sufficient to provide a maximum likelihood estimate for FRET, biological variability in FRET values can be revealed by performing the analysis for regions of interests in an image. Since the algorithm provides the probability of a combination of donor, FRET, and acceptor intensities observed in each individual pixel given a certain FRET efficiency, outlier pixels with low probabilities could be excluded from the analysis. Simulations carried out with low photon numbers in the presence and absence of outlier pixels revealed that the proposed approach can reliably and reproducibly estimate FRET efficiency. In addition, systematic evaluation of the simulation results showed that the distribution of pixel‐by‐pixel FRET efficiencies is skewed, and the mean of these FRET values is a biased and unreliable estimate of the FRET efficiency. In the absence of outlier pixels, FRET calculated from summed donor, FRET, and acceptor intensities proved to be as reliable as MLE. We conclude that MLE of FRET outperforms calculations using summed and pixel‐by‐pixel intensities in biologically relevant situations involving low photon numbers and outlier pixels. © 2014 International Society for Advancement of Cytometry