bluuebunny/crossref_metadata_2025 huggingface dataset:
Late Sodium Current And If Inhibition: Targets of New Antianginal Drugs
Authors: Das Uzzwal Kanti , Ahsan Syed Ali , Haque KMHS Sirajul , Ahmed Md. Khurshed
Published: February 2009

Ischaemic heart disease is the common cause of mortality and morbidity in developed countries despite tremendous development in treatment in last two decades. Recently cardiac Ion Channels and other cellular components have become the target of research for new cardiovascular drugs. A number of new drugs have emerged after pre-clinical and clinical trials. Ranolazine by inhibiting late sodium current in ventricular cardiomyocytes and ibavradine by inhibiting If current in pacemaker cells have emerged as effective new antianginal drugs. Both are discussed in this review article.

Key Words: Late Sodium current (IPNa), Diastolic tension, After depolarization, If current, heart rate.

(University Heart Journal 2007; 3 : 75-78)
Obstructive sleep apnea and cardiovascular effects-a review
Authors: Hossain AKM Mosharraf , Pasha Mostofa Midhat
Published: February 2009

Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing, affecting 5-15% of the population. It is characterized by intermittent episodes of partial or complete obstruction of the upper airway during sleep that disrupts normal ventilation and sleep architecture, and is typically associated with excessive daytime sleepiness, snoring, and witnessed apneas. Patients with obstructive sleep apnea present risk to the general public safety by causing 8-fold increase in vehicle accidents, and they may themselves also suffer from the physiologic consequences of OSA; these include hypertension, coronary artery disease, stroke, congestive heart failure, pulmonary hypertension, and cardiac arrhythmias. Of these possible cardiovascular consequences, the association between OSA and hypertension has been found to be the most convincing. Although the exact mechanism has not been understood, there is some evidence that OSA is associated with frequent apneas causing mechanical effects on intrathoracic pressure, cardiac function, and intermittent hypoxemia, which may in turn cause endothelial dysfunction and increase in sympathetic drive. Therapy with continuous positive airway pressure has been demonstrated to improve cardiopulmonary hemodynamics in patients with OSA and may reverse the endothelial cell dysfunction. Limited availability of diagnostic measures and unawareness of physicians, many patients with OSA remain undiagnosed. Awareness and timely initiation of an effective treatment may prevent potential deleterious cardiovascular effects of OSA. Key words: Obstructive Sleep apnea, Hypertension, Atherosclerosis, Continuous positive airway pressure. Â  doi:10.3329/uhj.v4i2.2075 University Heart Journal Vol. 4 No. 2 July 2008 p.41-45
Primary hyperaldosteronism- a resistant endocrine hypertension- A case report
Authors: Ahsan Syed Ali , Rahman Md Rubayat , Salman Mohammad , Haque Md Ashraful , Bari Ahmed Saiful , Sultan Md Ashraf Uddin
Published: February 2009

Â A thirty years old lady presented with uncontrolled hypertension and dizziness during working for last 5 years. She had history of termination of pregnancy due to treatment-resistant hypertension. Even in the post-partum period her blood pressure remains uncontrolled with more than three antihypertensive drugs. Her serum K+ level was low and USG of KUB & adrenal glands showed slightly increased right renal cortical echotexture; CT scan of abdomen revealed right Adrenal adenoma. She underwent unilateral adrenalectomy. Now, she has no complaints and her blood pressure is normal without any antihypertensive drugs. There is no target organ damage. Key words: Primary hyperaldosteronism, unilateral adrenal adenoma, resistant endocrine hypertension Â  doi:10.3329/uhj.v4i2.2077 University Heart Journal Vol. 4 No. 2 July 2008 p.49-50
The Importance of Medical and Nursing Sub-cultures in the Implementation of Clinical Information Systems
Authors: Braithwaite J. , Westbrook J. I. , Callen J. L.
Published: February 2009

Objective: To measure doctors’ and nurses’ perceptions of organisational culture and relate this to their attitudes to, and satisfaction with, a hospital-wide mandatory computerised provider order entry (CPOE) system in order to illuminate cultural compositions in CPOE use.

Methods: A cross-sectional survey design was employed. Data were collected by administering an organisational culture survey (Organisational Culture Inventory, OCI) along with a user-satisfaction survey to a population of 103 doctors and nurses from two clinical units in an Australian metropolitan teaching hospital. Clinicians from the hospital had used the CPOE system since 1991 to order and view clinical laboratory and radiology tests electronically for all patients. The OCI provides a measure of culture in terms of three general styles which distinguish between: constructive; passive/defensive, and aggressive/defensive cultures. The cluster which best describes the overall culture is the one that has the highest percentile score when the percentile scores of the four cultural norms included in the cluster are averaged. The user satisfaction survey asked questions relating to satisfaction with, and attitudes to, the system.

Results: We found identifiable sub-cultures based on professional divisions where doctors perceived an aggressive-defensive culture (mean percentile score = 43.8) while nurses perceived a constructive culture (mean percentile score = 61.5). There were significant differences between doctors and nurses on three of the attitude variables with nurses expressing more positive views towards CPOE than doctors.

Conclusion: The manifestation of sub-cultures within hospitals and the impact this has on attitudes towards clinical information systems should be recognized and addressed when planning for system implementation. Identification and management of the cultural characteristics of different groups of health professionals may facilitate the successful implementation and use of clinical information systems.
Categorizing Communication Errors in Integrated Hospital Information Systems
Authors: Ammenwerth E. , Saboor S.
Published: February 2009

Objectives: Hospital information systems (HIS) are the hospital’s nervous system. The HIS are mostly grown over several years, dedicated to specific needs and comprise individual workarounds. Changes to such complex systems may cause a variety of different negative side-effects. In order to understand the nature of incorrect communication in integrated HIS, a concise structured categorization of common communication problems and their reasons is essential. The objective of this paper is to present such a categorization, its development and verification.

Methods: We used a combined approach for the development of the error categorization: We started with a qualitative content analysis on available literature in PubMed. In order to ensure the validity and completeness of the results, we chose the method of problem-centered expert interviews.

Results: The resulting categorization of communication problems is represented as a five-level hierarchy. It comprises 81 problems that are related to the electronic communication. Further, it contains in total 229 entries that are either the reasons of these problems or recommendation for avoiding the problems.

Conclusion: To our knowledge there is no similar summary that concisely summarizes common communication problems and also refers to their underlying reasons. Equivalent content is mostly published in experience reports that just concentrate on single aspects. We used the details of such references in order to compile our categorization – it thus can be regarded as an intersection of relevant experiences. The categorization can raise a basic awareness on potential problems and supports the understanding of the underlying reasons. An evaluation in a real environment must prove whether the content of the categorization is correct.
Evaluating the Impact of Hybrid Electronic-paper Environments Upon Novice Nurse Information Seeking
Authors: Lemieux-Charles L. , Nagle L. , Eysenbach G. , Borycki E. M.
Published: February 2009

Objective: The purpose of this study was to investigate the effects of hybrid environments (i.e. where part of the patient record is paper-based and part of it is electronic) upon aspects of novice nurse information seeking (i.e. amount of information accessed, choice of key information sources, type of information and use of information seeking tactics).

Methods: A within group, laboratory, experimental study was conducted using two simulated environments (i.e. a paper environment and a hybrid environment). Thirty-five novice nurses participated in the study.

Results: Findings revealed significant differences between the paper and hybrid environments in terms of their effects upon aspects of novice nurse information seeking. Subjects accessed: 1) less information in the hybrid environment than the paper environment, 2) more non-electronic sources of information were accessed by novice nurses in the hybrid environment, and 3) novice nurses used more passive information seeking tactics in the hybrid environment than the paper environment. Qualitative findings from the cued recall data revealed subjects experienced increased cognitive load in the hybrid environment.

Conclusions: Hybrid environments may affect aspects of novice nurse information seeking. Future research should explore the effects of hybrid environments upon the information seeking of other types of health professionals (e.g. physicians, physiotherapists) with differing levels of expertise (i.e. novice, intermediate and expert).
Analyzing Data from Nonrandomized Group Studies
Authors: Bray Jeremy , Schlenger William , Zarkin Gary , Galvin Deborah
Published: February 2009

Researchers evaluating prevention and early intervention programs must often rely on diverse study designs that assign groups to various study conditions (e.g., intervention versus control). Although the strongest designs randomly assign these groups to conditions, researchers frequently must use nonrandomized research designs in which assignments are made based on the characteristics of the groups. With nonrandomized group designs, little guidance is available on how best to analyze the data. We provide guidance on which techniques work best under different data conditions and make recommendations to researchers about how to choose among the various techniques when analyzing data from a pre-test/post-test nonrandomized study. We use data from the Center for Substance Abuse Prevention’s Workplace Managed Care initiative to compare the performance of the various methods commonly applied in quasi-experimental and group assignment designs.
Library automation: strategies for library human resource management
Authors: Arachchi Theja Kuruppu , De Silva WRG
Published: February 2009

This article examines the automation processes University libraries and the new managerial issues coming on in this technological era. A survey was used ascertain the library automation practices in University libraries and to determine important managerial functions for working with library staff. All the university libraries including faculty libraries were deemed as the study population. The results showed that library catalogue had been computerized in most of the University libraries (89.25%). Acquisition, circulation, serials controls, theses and dissertations processing, selective dissemination of information and interlibrary loans were identified as the processes that need improvements with new technology. The study further indicated that shared motivating vision, open communication, participative management, appropriate staffing and training were important strategies for working with library staff motivating them to provide efficient and effective service in the new technological environment. Keywords: Library automation, library management, change management, human resource management, university libraries   doi: 10.4038/jula.v11i0.325 Journal of the University Librarians Association of Sri Lanka (Vol. 11) 2007 p.98-110
The Effect of the Superconducting Transition on Plastic Deformation of Ultrafine‐Grained Aluminum
Authors: Estrin Yuri , Fomenko Vera , Grigorova Tatyana , Isaev Nikolai , Pustovalov Vitaliy , Shumilin Sergiy , Janecek Milos
Published: February 2009

In this paper, the mechanical behavior of ultrafine‐ and coarse‐grained Al at a record low temperature of 0.52 K is presented. It is demonstrated that grain refinement by equal channel angular pressing leads to increased flow stress and to a change in the strain hardening behavior of Al at this temperature. Special emphasis is placed on the effect of the superconducting transition on the mechanical behavior in the different microstructural conditions. It is shown that the magnitude of the stress jump associated with the transition correlates with the strain hardening behavior which, in turn, is related to the microstructure of the material.
Genetic polymorphisms in glutathione S‐transferases and cytochrome P450s, tobacco smoking, and risk of non‐Hodgkin lymphoma
Authors: Kilfoy Briseis A. , Zheng Tongzhang , Lan Qing , Han Xuesong , Qin Qin , Rothman Nathaniel , Holford Theodore , Zhang Yawei
Published: February 2009

We investigated variation in glutathione S‐transferases (GSTs) and cytochrome P450s (CYPs), and smoking in a population‐based case‐control study of NHL including 1,115 women. Although risk of NHL was not altered by variant polymorphisms in GSTs or CYPs, it was significantly changed for DLBCL when considered in conjunction with smoking behavior, though only in nonsmokers. An increased risk of DLBCL in nonsmokers was associated with the variant G allele for GSTP1 (OR = 1.6, 95% CI 1.0–2.3) and CYP1A1 (OR = 2.4; 95% CI 1.0–5.7), but a decreased risk for the variant G allele for CYP1B1 (OR = 0.6, 95% CI 0.4–1.0). Our results confer support investigation of the gene‐environment interaction in a larger study population of DLBCL. Am. J. Hematol. 2009. © 2009 Wiley‐Liss, Inc.
Spectroscopic Tracking of Molecular Transport Junctions Generated by Using Click Chemistry
Authors: Chen Xiaodong , Braunschweig Adam B. , Wiester Michael J. , Yeganeh Sina , Ratner Mark A. , Mirkin Chad A.
Published: February 2009

Mit einem Klick die Lücke gefüllt: Mithilfe der Klick‐Chemie wird ein Moleküldraht, der eine durch „On‐Wire“‐Lithographie erzeugte Nanolücke überbrückt, in situ modular aufgebaut (siehe Bild). Der Draht entsteht in hoher Ausbeute, und es können unterschiedliche Moleküle getestet werden; die Triazolgruppe bleibt auch im Moleküldraht konjugiert. Der Aufbau des Drahtes wurde Raman‐spektroskopisch verfolgt.

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High‐Resolution Structural Characterization of a Helical α/β‐Peptide Foldamer Bound to the Anti‐Apoptotic Protein Bcl‐xL
Authors: Lee Erinna F. , Sadowsky Jack D. , Smith Brian J. , Czabotar Peter E. , Peterson‐Kaufman Kimberly J. , Colman Peter M. , Gellman Samuel H. , Fairlie W. Douglas
Published: February 2009

Get into the groove: The first high‐resolution structure of a foldamer bound to a protein target is described (see picture; foldamer in sticks). The foldamer consists of α‐ and β‐amino acid residues and is bound to the anti‐apoptotic protein Bcl‐xL. The overall binding mode and key interactions observed in the foldamer/Bcl‐xL complex mimic those seen in complexes of Bcl‐xL with natural α‐peptide ligands. Additional contacts in the foldamer/Bcl‐xL complex involving β‐amino acid residues appear to contribute to binding affinity.

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Spectroscopic Tracking of Molecular Transport Junctions Generated by Using Click Chemistry
Authors: Chen Xiaodong , Braunschweig Adam B. , Wiester Michael J. , Yeganeh Sina , Ratner Mark A. , Mirkin Chad A.
Published: February 2009

Click to fill the gap: The in situ modular fabrication of molecular transport junctions in nanogaps generated by on‐wire lithography is achieved by using click chemistry (see picture). The formation of molecular junctions proceeds in high yields and can be used to test different molecules; the triazole group also maintains conjugation in the molecular wires. Raman spectroscopy is used to characterize the molecular assembly processes.

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Pharmacokinetics of pyrrole‐imidazole polyamides after intravenous administration in rat
Authors: Fukasawa Akiko , Aoyama Takahiko , Nagashima Takashi , Fukuda Noboru , Ueno Takahiro , Sugiyama Hiroshi , Nagase Hiroki , Matsumoto Yoshiaki
Published: February 2009

The pharmacokinetics of pyrrole (Py)‐imidazole (Im) polyamides was studied in rats after the intravenous administration of these compounds. Py‐Im polyamide (A) was composed of Ac‐ImPyPy‐ImPyPy‐β‐Dp (β: β‐alanine, Dp: N,N‐dimethylaminopropylamide). Py‐Im polyamide (B) was composed of Ac‐PyIm‐β‐ImIm‐PyPy‐β‐PyPy‐β‐Dp. Py‐Im polyamide (C) was composed of Ac‐PyPy‐β‐PyImPy‐PyPyPy‐β‐ImPy‐β‐Dp. The molecular weight of Py‐Im polyamide (A) was 1035.12, that of Py‐Im polyamide (B) was 1422.51 and that of Py‐Im polyamide (C) was 1665.78. After the intravenous injection of Py‐Im polyamide (A) at 1.3, 2.0, 7.5 and 15.0 mg/kg, Py‐Im polyamides (B) and (C) at 1.0, 2.0, 3.0 and 5.0 mg/kg, the average systemic clearance and the volume of distribution at the steady state obtained by a non‐compartmental method were in the ranges of 4.6–6.4 ml/min/kg and 244–412 ml/kg, 8.9–10.3 ml/min/kg and 1990–4567 ml/kg, and 7.3–11.9 ml/min/kg and 407–667 ml/kg, respectively. Dose linearity of Py‐Im polyamides was observed. The plasma concentration‐time profiles after the intravenous administration of Py‐Im polyamides (A) and (B) were fitted well by a two‐compartment model. Py‐Im polyamide (C) was observed at high concentrations in the lungs. The plasma concentration‐time profiles after the intravenous administration of Py‐Im polyamide (C) were described using a catenary two‐compartment model. This model is useful for describing the time course after the administration of high‐molecular‐weight Py‐Im polyamides. Copyright © 2009 John Wiley & Sons, Ltd.
Biotin
Authors: Zempleni Janos , Wijeratne Subhashinee S.K. , Hassan Yousef I.
Published: February 2009

Biotin is a water‐soluble vitamin and serves as a coenzyme for five carboxylases in humans. Biotin is also covalently attached to distinct lysine residues in histones, affecting chromatin structure and mediating gene regulation. This review describes mammalian biotin metabolism, biotin analysis, markers of biotin status, and biological functions of biotin. Proteins such as holocarboxylase synthetase, biotinidase, and the biotin transporters SMVT and MCT1 play crucial roles in biotin homeostasis, and these roles are reviewed here. Possible effects of inadequate biotin intake, drug interactions, and inborn errors of metabolism are discussed, including putative effects on birth defects. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
Fluorescence‐based analysis of enzymes at the single‐molecule level
Authors: Blank Kerstin , De Cremer Gert , Hofkens Johan
Published: February 2009

Enzymes, and proteins in general, consist of a dynamic ensemble of different conformations, which fluctuate around an average structure. Single‐molecule experiments are a powerful tool to obtain information about these conformations and their contributions to the catalytic reaction. In contrast to classical ensemble measurements, which average over the whole population, singlemolecule experiments are able to detect conformational heterogeneities, to identify transient or rare conformations, to follow the time series of conformational changes and to reveal parallel reaction pathways. A number of single‐molecule studies with enzymes have proven this potential showing that the activity of individual enzymes varies between different molecules and that the catalytic rate constants fluctuate over time. From a practical point of view this review focuses on fluorescence‐based methods that have been used to study enzymes at the single‐molecule level. Since the first proof‐of‐principle experiments a wide range of different methods have been developed over the last 10 years and the methodology now needs to be applied to answer questions of biological relevance, for example about conformational changes induced by allosteric effectors or mutations.
Research regarding the implementation of an interactive application for educational improvement of engineering drawing
Authors: Pando Cerra Pablo , Alvarez Peñin Pedro , Perez Morales Maximo , Higuera Garrido Alberto
Published: February 2009

In the current European university reform teacher‐based education is replaced by another form of teaching, which is more focused on the students. To facilitate this task, a self‐learning‐oriented application called AIMEC‐DT was developed. This article discusses, by means of an educational experience, the advantages of using these types of interactive tools adapted to achieve that goal. The results obtained allow us to conclude that their use can be a significant improvement in teaching in engineering. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 183–192, 2011
Gating Characteristics of Thermo‐Responsive Membranes with Grafted Linear and Crosslinked Poly(N‐isopropylacrylamide) Gates
Authors: Chen Y.‐C. , Xie R. , Yang M. , Li P.‐F. , Zhu X.‐L. , Chu L.‐Y.
Published: February 2009

Thermo‐responsive porous membranes with grafted linear and crosslinked poly(N‐isopropylacrylamide) (PNIPAM) gates are successfully prepared at temperatures above and below the lower critical solution temperature (LCST) of PNIPAM by using a plasma‐induced grafting polymerization method, and the effects of operation pressure and grafting temperature on the thermo‐responsive gating characteristics of the prepared membranes are investigated systematically. The fluxes of water through the grafted membranes increase simply with increasing the operation pressure no matter whether the environmental temperature is 40 °C or 25 °C. Under high operation pressure (e.g., higher than 0.14 MPa), the grafted linear PNIPAM gates deform to a certain extent, whereas the grafted crosslinked PNIPAM gates do not deform. For both membranes with grafted linear and crosslinked PNIPAM gates, the membranes prepared at 25 °C (below the LCST of PNIPAM) show larger thermo‐responsive gating coefficients than those prepared at 40 °C (above the LCST of PNIPAM), which results from different distributions of grafted PNIPAM gates in the membrane pores. When the PNIPAM gates are grafted at 25 °C, the grafted layer near the membrane surface is much thicker than that inside the membrane pores; on the other hand, when the PNIPAM gates are grafted at 40 °C, the grafted layer is homogeneously formed throughout the whole pore length. Both linear and crosslinked grafted PNIPAM gates in the membrane pores exhibit stable and repeatable thermo‐responsive “open‐close” switch performances under the operation pressure of 0.26 MPa. The results in this study provide valuable guidance for designing, fabricating, and operating thermo‐responsive gating membranes with desirable performances.
On‐line Statistical Process Monitoring and Fault Diagnosis in Batch Baker's Yeast Fermentation
Authors: Berber R. , Atasoy I. , Yuceer M. , Deniz G.
Published: February 2009

This study involves real‐time monitoring and fault diagnosis in batch baker's yeast fermentation. A specific Real Time Statistical Process Analysis and Control (RT‐SPAC) program was developed to monitor instantaneous reaction conditions. The air flow rate fed to the reactor, temperature, pH, and dissolved oxygen concentration in a laboratory‐size fermenter were monitored and recorded by means of on‐line sensors. Under control of the RT‐SPAC program, 22 batch baker's yeast fermentation operations were carried out. In the first 20 operations, an ordinary process was followed under previously defined nominal operating conditions. Historical data collected from these batches were then used for on‐line Dynamic Principal Component Analysis (DPCA) in the course of the following two batches. The last two batches were implemented such that some deliberate faults (in temperature and pH) were introduced during the operation. The results indicated that the software was capable of capturing the process faults, and furthermore the possible causes of these faults were identified by contribution plots.
Reactivities of the Prism‐Shaped Diamondoids [1(2)3]Tetramantane and [12312]Hexamantane (Cyclohexamantane)
Authors: Fokin Andrey A. , Tkachenko Boryslav A. , Fokina Natalie A. , Hausmann Heike , Serafin Michael , Dahl Jeremy E. P. , Carlson Robert M. K. , Schreiner Peter R.
Published: February 2009

Functionalized nanodiamonds: Various functional groups have been incorporated into the structures of the naturally occurring diamondoids [1(2)3]tetramantane and [12312]hexamantane (cyclohexamantane), which represent hydrogen‐terminated prism‐shaped nanodiamonds (see picture). The attachment points define the use of these diamond‐like molecules as geometric building blocks for a variety of applications.

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Various functional groups have been incorporated into the structures of the naturally occurring diamondoids [1(2)3]tetramantane and [12312]hexamantane (cyclohexamantane), which represent hydrogen‐terminated prism‐shaped nanodiamonds. The selectivities of the CH substitutions in [1(2)3]tetramantane depend on the reagent employed and give products substituted at either central (through bromination) or peripheral (through nitroxylation and photo‐oxidation) positions. The hydrogen‐coupled electron‐transfer mechanism of CH nitroxylation with the model electrophile NO2+⋅⋅⋅HNO3 was verified computationally at the B3PW91 and MP2 levels of theory by utilizing the 6‐31G(d) and cc‐pVDZ basis sets. The thermodynamically controlled nitroxylation/isomerization of [1(2)3]tetramantane allows the preparation of peripherally trisubstituted derivatives, which were transformed into tripod‐like nanodiamond building blocks. The bromination of cyclohexamantane selectively gives the 2‐bromo derivative, reproducing the chemical behavior of the {111} surface of the hydrogen‐terminated diamond.
Palladium‐Catalyzed Heck Reaction of Polyoxometalate‐Functionalised Aryl Iodides and Bromides with Olefins
Authors: Zhu Yulin , Wang Longsheng , Hao Jian , Yin Panchao , Zhang Jin , Li Qiang , Zhu Li , Wei Yongge
Published: February 2009

Organically derivatised polyoxometalate (POM) clusters containing bromo or iodo groups can undergo ligand‐free, Pd‐catalysed Heck carbon–carbon coupling reactions with alkenes, with bromomagnesium phenylamide as a base (see scheme). This protocol offers a new route to organic–inorganic hybrid molecular materials in which POM clusters are covalently bonded with organic conjugated segments.

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Synthesis and Resolution of Planar–Chiral Ruthenium–Palladium Complexes with ECE′ Pincer Ligands
Authors: Bonnet Sylvestre , Li Jie , Siegler Maxime A. , von Chrzanowski Lars S. , Spek Anthony L. , van Koten Gerard , Klein Gebbink Robertus J. M.
Published: February 2009

Feel the pinch! Planar–chiral, cationic, ruthenium–palladium complexes based on η6,η1‐coordinated ECE′ pincer ligands are synthesized as racemic mixtures by reacting ECE′–palladium complexes and [Ru(C5R5)(MeCN)3]+ arenophiles (R=H or Me). Chiral resolution of the cationic complexes was achieved by using the chiral counterion [Δ‐TRISPHAT]−, and solving the X‐ray crystal structure of one diastereoisomer (shown here).

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A N,N′‐Dioxide–Copper(II) Complex as an Efficient Catalyst for the Enantioselective and Diastereoselective Mannich‐Type Reaction of Glycine Schiff Bases with Aldimines
Authors: Shang Deju , Liu Yanling , Zhou Xin , Liu Xiaohua , Feng Xiaoming
Published: February 2009

Mild mannered! A highly diastereo‐ and enantioselective Mannich‐type reaction of glycine Schiff base 1 has been developed by using the N,N′‐dioxide L‐CuII complex as a catalyst. Various optically active anti‐α,β‐diamino acid esters were obtained in good yields with up to 96:4 d.r. and 97 % ee. This straightforward method features a low catalyst loading and mild reaction conditions.

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ChemInform Abstract: Efficient Copper‐Catalyzed Coupling of 2‐Haloacetanilides with Phosphine Oxides and Phosphites under Mild Conditions.
Authors: Jiang Deshou , Jiang Qun , Fu Hua , Jiang Yuyang , Zhao Yufen
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Isolation, Structure Determination, and Synthesis of Galaxamide, a Rare Cytotoxic Cyclic Pentapeptide from a Marine Algae Galaxaura filamentosa.
Authors: Xu Wen‐Jie , Liao Xiao‐Jian , Xu Shi‐Hai , Diao Jian‐Zhong , Du Bin , Zhou Xu‐Long , Pan Shan‐Shan
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cebulactams A1 and A2, New Macrolactams Isolated from Saccharopolyspora cebuensis, the First Obligate Marine Strain of the Genus Saccharopolyspora.
Authors: Pimentel‐Elardo Sheila Marie , Gulder Tobias A. M. , Hentschel Ute , Bringmann Gerhard
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Lanthanide (III) salt complexes: Arrayed acid‐base networks for enantioselective catalysis. The nitroaldol reaction upon aldehydes and trifluoromethylketones
Authors: Saá José M. , Tur Fernando , González José
Published: February 2009

Shelf stable, chiral‐at‐metal, D3 symmetric, 3:1 complexes of lanthanide (III) triflate salts are easily available by complexation with binolam (3,3′‐diethylaminomethyl‐2,2′‐dihydroxy‐1,1′‐dinaphthalene) 1 or binolamo (3,3′‐diethylaminooxymethyl‐2,2′‐dihydroxy‐1,1′‐dinaphthalene) 2 ligands. The resulting compounds 3Ln and 4Ln are isostructural, as demonstrated by their spectroscopic data, and possess an arrayed acid‐base LABABB network. Complexes are kinetically labile, and in solution undergo hydrolysis by water. The lanthanum complex derived from binolam, i.e., (Δ,S,S,S)‐ (binolam)3.la(OTf)33La was found to be the most active catalyst in promoting direct nitroaldol reactions upon aldehydes and trifluoromethyl ketones, thereby giving rise to secondary nitroalcohols and tertiary α‐trifluoromethyl‐β‐nitroalcohols, respectively, with high ee in both cases. Enantiomerically enriched tertiary nitroalcohols were easily reduced to the corresponding aminoalcohols having a quaternary asymmetric carbon without loss of enantiomeric purity. Chirality 2009. © 2009 Wiley‐Liss, Inc.
Enantiopure cyclic O‐substituted phenylphosphonothioic acid: Synthesis and chirality‐recognition ability
Authors: Ribeiro Nigel , Kobayashi Yuka , Maeda Jin , Saigo Kazuhiko
Published: February 2009

As a new acidic selector (resolving agent), we synthesized an enantiopure O‐alkyl phenylphosphonothioic acid with a seven‐membered ring ((R)‐5), which was designed on the basis of the results for the enantioseparation of 1‐arylethylamine derivatives with acyclic O‐ethyl phenylphosphonothioic acid (I). The phosphonothioic acid (R)‐5 showed unique chirality‐recognition ability in the enantioseparation of 1‐naphthylethylamine derivatives, aliphatic secondary amines, and amino alcohols; the ability was complementary to that of I. The X‐ray crystallographic analyses of the less‐ and more‐soluble diastereomeric salts showed that hydrogen‐bonding networks in the salt crystals are 21‐column‐type with a single exception which is cluster‐type. In the cases of the 21‐column‐type crystals, stability of the crystals is firstly governed by hydrogen bonds to form a 21‐column and secondly determined by intra‐columnar T‐shaped CH/π interaction(s), intra‐columnar hydrogen bond(s), inter‐columnar van der Waals interaction and/or inter‐columnar T‐shaped CH/π interaction(s). In contrast, the cluster‐type salt crystal is stabilized by the assistance of inter‐cluster T‐shaped CH/π and van der Waals interactions. To realize still more numbers of intra‐ and inter‐columnar and ‐cluster T‐shaped CH/π interactions, the seven‐membered ring of (R)‐5 plays a considerable role. Chirality 23:438–448, 2011. © 2009 Wiley‐Liss, Inc.
Effects of solvent on chiral and enantiomeric separation of Koga bases using derivatized amylose chiral stationary phase
Authors: Guo Hong‐Xun , Wu Steven , Nadeau Kelly , Moniz George A. , Caille Sebastian
Published: February 2009

The separation of R,R‐, S,S‐, and meso‐Koga bases on derivatized amylose chiral stationary phases (CSP) has been studied using different alcohol and alcohol‐hexane mixtures as eluant. Straight‐chain and branched alcohols with carbon numbers from one to four were investigated. The carbon number and geometry of the alcohol impacts the separation of Koga bases. The optimal separations were obtained using a mixture of methanol with linear or branched alcohol. Also, the elution order of meso‐ and R,R‐Koga base was switched as content of branched alcohol increases in cosolvent. The study of acidic and basic additive effects demonstrated that maintaining analytes in the free base state is crucial in order to achieve retention and separation. TEA alone or TEA and TFA mixture were used in the studies. Chirality 2010. © 2009 Wiley‐Liss, Inc.
A reformulation of the Lesaint–Raviart discontinuous Galerkin method for advection equations
Authors: Fortin M. , Fortin A. , Benmoussa K. , Tibirna C.
Published: February 2009

The Lesaint–Raviart method was introduced in 1974 for the numerical solution of the neutron transport equation. It is probably the first discontinuous Galerkin (DG) method ever introduced. In this paper, we propose an equivalent formulation of this DG‐type method for advection problems that can be easily implemented into existing finite element codes. The proposed formulation also presents some advantages in domains where there is no inflow boundary such as those encountered in the tire industry. Copyright © 2009 John Wiley & Sons, Ltd.
ONIOM Study of Isomerization Reactions of Aromatic Hydrocarbons in Acidic Mordenite Zeolite
Authors: Yang Jing
Published: February 2009

Two different mechanisms: Shift 1,2‐isomerization and isomerization via the disproportionation reaction are investigated for aromatic hydrocarbons over acidic mordenite zeolite by using our own n‐layered integrated molecular orbital and molecular mechanics (ONIOM) scheme. The picture shows a schematic energy profile for the isomerization of toluene catalyzed by acidic mordenite.

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The geometrical structures and energies of isomerization reactions of aromatic hydrocarbons catalyzed by the 128T cluster model of acidic mordenite zeolite are studied by using our own n‐layered integrated molecular orbital and molecular mechanics (ONIOM) scheme. The aromatic hydrocarbons investigated are toluene, xylenes, and trimethylbenzenes. Two proposed intramolecular reaction mechanisms, that is, shift 1,2‐isomerization and isomerization via the disproportionation reaction, are studied and discussed in detail. Both of the mechanisms firstly proceed by protonation of aromatic hydrocarbons to form the aromatic‐based carbenium ions. Attempts to determine the prevailing reaction mechanism of the isomerization are evaluated. In most cases, the isomerization reactivity sequence is: trimethylbenzenes>xylenes>toluene. The conclusions obtained using the ONIOM scheme agree with the available periodic DFT and experimental results on acidic mordenite zeolite.
Biosurfactants from Urban Green Waste
Authors: Montoneri Enzo , Boffa Vittorio , Savarino Piero , Perrone Daniele G. , Musso Giorgia , Mendichi Raniero , Chierotti Michele R. , Gobetto Roberto
Published: February 2009

From waste came forth surfactants: Humic acid like substances isolated from 0–60 day‐old compost display excellent surface activity and solvent properties. These biosurfactants were used to solubilize a dye in water below and above their critical micellar concentration. The biosurfactant unimers appear to have higher dye‐solubilizing power than the corresponding micelles.

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Humic acid like substances isolated from compost show potential as chemical auxiliaries. In the present study, three surfactant samples were obtained from green waste composted for 0–60 days to assess aging effects of the source on the properties of the products. The surface activity, dye solubility enhancement, and chemical nature of these substances were compared. No differences in performance were established among the samples. They lower water surface tension and enhance the dye solubility upon increasing their concentration. However, the ratio of soluble dye to added surfactant is higher in the premicellar than in the postmicellar concentration region. Structural investigations indicated the humic acid like substances to be amphiphiles with molecular weights in the range of 1–3×105 g mol−1. The surfactant samples were also compared to sodium dodecylbenzenesulfonate, polyacrylic acid, and soil and water humic substances. The results encourage the application of compost as a source of low‐cost biosurfactant.
Plasma‐Enhanced Atomic Layer Deposition of Semiconductor Grade ZnO Using Dimethyl Zinc
Authors: Rowlette Pieter C. , Allen Cary G. , Bromley Olivia B. , Dubetz Amy E. , Wolden Colin A.
Published: February 2009

Zinc oxide films are deposited over the temperature range 25–120 °C by plasma‐enhanced atomic layer deposition (PEALD) using dimethyl zinc (DMZ, Zn(CH3)2) as the metal precursor. DMZ is unreactive with molecular oxygen under process conditions, facilitating its utility for PEALD. The deposition rate is independent of plasma exposure (1–5 s) and saturates for DMZ exposures ≥75 mTorr s. The saturated growth per cycle increases from 1.6 to 2.9 Å per cycle as the temperature is increased from 25 to 85 °C, and remains constant in the range 85–120 °C. Over the narrow range explored, substrate temperature has a dramatic impact on film structure and properties. Polycrystalline films with a (100) texture are obtained at room temperature, with the preferred orientation evolving to the (002) direction as the temperature increases. The electrical resistivity decreases exponentially from 270 at room temperature to values of ∼5 Ω cm within the ALD window. Compositional analysis shows that films at low temperature are contaminated by carbon and hydroxyl impurities, however these defects are attenuated with temperature and not detected in films deposited within the ALD window. Room temperature photoluminescence is dominated by strong emission from ZnO defects in most films, however these signals are attenuated and strong band edge emission is observed for films deposited at 120 °C.
Imprint cytology of pancreatoblastoma: A case report and review of the literature
Authors: Sahu Kausalya Kumari , Rau Aarathi R. , Bhat Narayana , Kini Jyoti R. , Mathai Alka Mary
Published: February 2009

Pancreatoblastoma is a rare tumor with ∼60 cases described in the English literature and only five case reports illustrating the cytologic findings, four by fine‐needle aspiration cytology and one by imprint cytology. We herein report the sixth case diagnosed by imprint cytology. Both the cytologic and histopathologic literatures are reviewed, and the pathologic variations observed in our case are also documented. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Synthesis, Characterization, Thermodynamic and Kinetic Properties of a New Series of Dinuclear PtII Complexes
Authors: Ertürk Hakan , Puchta Ralph , van Eldik Rudi
Published: February 2009

The dinuclear PtII complexes bis{[(1R,2R)‐(–)‐1,2‐diaminocyclohexane]chloroplatinum(II)}(μ‐1,8‐octanediamine), bis{[(1R,2R)‐(–)‐1,2‐diaminocyclohexane]chloroplatinum(II)}(μ‐1,10‐decanediamine) and bis{[(1R,2R)‐(–)‐1,2‐diaminocyclohexane]chloroplatin(II)}[μ‐1,4‐bis(3‐pyridyl)buta‐1,3‐diyne] were synthesized. Acid‐base titrations and concentration and temperature dependent measurements of the reactions with chloride and thiourea were performed to study the influence of the nature of the bridging ligand on the thermodynamic and kinetic properties of the complexes. The reactions with chloride and thiourea were followed under pseudo‐first‐order conditions by stopped‐flow and UV/Vis spectrophotometry. The results indicate that the bridging ligand has an influence on the reactivity and stability of the complexes towards nucleophiles as well as on possible electronic interactions between the two PtII centres. The experimental results are discussed in reference to structures obtained by DFT (BP86/LACVP*) calculations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Species identification in mammals from mixed biological samples based on mitochondrial DNA control region length polymorphism
Authors: Pun Ka‐Man , Albrecht Catherine , Castella Vincent , Fumagalli Luca
Published: February 2009

The ability to identify the species origin of an unknown biological sample is relevant in the fields of human and wildlife forensics. However, the detection of several species mixed in the same sample still remains a challenge. We developed and tested a new approach for mammal DNA identification in mixtures of two or three species, based on the analysis of mitochondrial DNA control region interspecific length polymorphism followed by direct sequencing. Contrary to other published methods dealing with species mixtures, our protocol requires a single universal primer pair and is not based on a pre‐defined panel of species. Amplicons can be separated either on agarose gels or using CE. The advantages and limitations of the assay are discussed under different conditions, such as variable template concentration, amplicon sizes and size difference among the amplicons present in the mixture. For the first time, this protocol provides a simple, reliable and flexible method for simultaneous identification of multiple mammalian species from mixtures, without any prior knowledge of the species involved.
Characterization of the interaction of cefadroxil with different metal ions using CE
Authors: Auda Sayed H. , Mrestani Yahya , Ahmed Ahmed M. S. , Neubert Reinhard H. H.
Published: February 2009

The present study describes the application of CE to investigate the interaction between a cephalosporin, cefadroxil and different metal ions. This study aims at quantifying the interaction of cefadroxil with Zn2+, Al3+, Fe3+, Cu2+ and Co2+ ions using the effective electrophoretic mobility as a parameter for calculation of the reaction association constant (K). For this purpose, the electrophoretic mobilities of cefadroxil at different metal ion concentrations in citrate buffer pH 3.6 were determined. A mathematical model to calculate the association constant between cefadroxil and metal ions was used. The results showed that a strong change in the cefadroxil electrophoretic mobility was observed by increasing the metal ion concentrations. The results revealed that by increasing the concentration of metal ions in the running buffer the degree of complexation increases too. On the basis of the results, the strength of the interaction of cefadroxil with the investigated metal ions follows the order Zn2+>Cu2+>Co2+>Fe3+>Al3+. The association constant of the investigated reactions ranged from 451.57 to 1546.52 L/mmol. The results indicate that it is possible to characterize the interaction between cefadroxil and metal ions quantitatively using CE.
The Use of Fluorocarbon Surfactants to Improve the Manufacture of PEM Fuel Cell Electrodes
Authors: Wills R. G. A. , Watt‐Smith M. J. , Walsh F. C.
Published: February 2009

Fluorocarbon surfactants are used to improve surface wetting during the screen printing of carbon black inks onto PEM fuel cell electrodes. The fluorosurfactants were tested in inks that comprised a Nafion® ionomer solution with platinum‐loaded carbon black. Four commercially available fluorosurfactants (Zonyl FSO, Zonyl 1033D, Forafac 1098 and Novec FC 4430) were screened and assessed for electrochemical activity (via cyclic voltammetry), leaching and the ability to form ink layers. Good wetting characteristics were observed and the inks showed a similar specific electrochemical active area (200–430 cm2 mg–1Pt) to a standard reference ink (370 cm2 mg–1Pt), indicating that the surfactants did not adversely adsorb on the platinum catalyst surface or block the adsorption/desorption of hydrogen. Additionally, the fluorosurfactants in the cured inks were shown to be electrochemically inactive in the potential region relevant to fuel cell operation.
Intracerebral granulocyte‐macrophage colony‐stimulating factor induces functionally competent dendritic cells in the mouse brain
Authors: Mausberg Anne Kathrin , Jander Sebastian , Reichmann Gaby
Published: February 2009

Granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) is a hematopoietic growth factor and a proinflammatory cytokine. While GM‐CSF is lacking in normal brain tissue, it is expressed under pathological conditions and correlates with the presence of dendritic cells (DC). However, the role of GM‐CSF for the onset of immune responses in the brain is still unclear. To analyze the role of GM‐CSF for the induction and functional activity of immune cells in the brain, we performed chronic intracerebroventricular administration of GM‐CSF to the brains of adult mice. After GM‐CSF administration, intracerebral leukocytes (ICL) were characterized by means of flow cytometry, immunohistochemistry, and an ex vivo functional assay. GM‐CSF treatment significantly increased the number of leukocytes expressing high levels of CD45, indicative of peripheral, blood‐derived cells. The infiltrating cells were preferentially DC of the myeloid lineage (CD45high CD11c+ CD11b+) with an activated phenotype characterized by upregulated expression of MHCII and the costimulatory ligand CD80. Furthermore, DC from GM‐CSF treated mice were fully competent to activate naive allogeneic T cells in a mixed leukocyte reaction. In contrast, intracerebroventricular IFN‐γ administration stimulated MHCII expression on cells resembling resident microglia, but did not induce comparable presence of DC. Taken together, intracerebroventricular GM‐CSF treatment results in high numbers of DC in the brain. Moreover, these GM‐CSF‐induced DC display an activated phenotype and exhibit the capacity to act as fully competent DC even without a further inflammatory stimulus. © 2009 Wiley‐Liss, Inc.