bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Surface Modification on the Dispersion Property of VGC
Authors: FU Yaqin , HAN Chunshao , NI Qingqing
Published: June 2009

In view of the easy agglomeration issue of vapor grown carbon fiber (VGCF) and the poor interfacial adhesion between VGCF and matrix resin, two‐step surface modification with hydrogen peroxide and concentrated nitric acid was performed on VGCF. The surface structure and dispersion of VGCF before and after modification were tested and analyzed by XRD, TGA, FTIR, UV‐visible spectrum and SEM. Moreover, VGCF/SMPU composites were prepared via a solution mixing method taking shape memory polyurethane (SMPU) as matrix, and the mechanical properties of the composites were also tested. The graphite crystal structure of VGCF showed very little change after modification, the concentration of oxygen‐containing functional groups on the surface of VGCF was visibly increased, and the dispersion and dispersion stability of VGCF in organic solvent were also clearly improved. In the cross section of the VGCF/SMPU composites, the dispersion of VGCF in matrix and the VGCF‐matrix interfacial adhesion observed through SEM were both enhanced to a certain extent after surface modification. The two‐step surface modified VGCF had more obvious mechanical reinforcement effects on the composites than that of the pristine VGCF.
Enhanced Binding of a Non‐hydrogen Bond Ligand to DNA by Introducing an Apurine/Apyrimidine Site
Authors: SHAO Yong , NIU Zhenjiang , CHEN Jianrong , ZHANG Liangke
Published: June 2009

Intercalators are well known for their DNA binding specificity by inserting between base pairs, whereas the binding event occurring to apurine/apyrimidine site (AP site)‐containing DNA for this type of noncovalent interaction is still not highlighted although AP site is frequently in vivo produced in living cells. Here proflavine (PF) as an example is used to investigate the binding specificity of the AP site in DNA for a non‐hydrogen bond ligand. Experimental results indicate that the AP site should be the preferential binding site for PF. The intrinsic binding constant of PF for the AP site is one order of magnitude greater than that occurring for PF intercalation. Additionally, the thermostability of the AP site‐containing DNA is significantly increased after PF binding. The PF bound to the AP site should adopt a specific binding orientation distinguishable from that by which PF intercalated into base pairs. The results obtained here should be very useful for judging biochemical and biophysical effectiveness of small molecules based on their different binding behavior to DNA.
One‐pot Three‐component Synthesis of 3,4‐Dihydroquinazolin‐4‐one Derivatives under Aqueous Medium or Solvent‐free Conditions
Authors: BANDGAR Babasaheb P. , MORE Parmeshwar. E. , KAMBLE Vinod T.
Published: June 2009

3,4‐Dihydroquinazolin‐4‐one derivatives were synthesized in moderate to high yields by one‐pot condensation of anthranilic acid, amines, and formic acid or orthoester without catalyst under aqueous medium or solvent‐free conditions.
An Efficient Microwave‐assisted Synthesis of Pyrido[2,3‐d]pyrimidine Derivatives
Authors: TU Shujiang , WU Shanshan , HAN Zhengguo , HAO Wenjuan
Published: June 2009

A series of new pyrido[2,3‐d]pyrimidine derivatives were synthesized by multi‐component reactions of equimolar amount of aromatic aldehydes with barbituric acids (barbituric acid or 1,3‐dimethylbarbituric acid) and 5‐amino‐2‐methylbenzo[d]thiazol in mixed solvent of glacial acetic acid and ethylene glycol without catalyst under microwave irradiation. This one‐pot method has the advantage of good yields (90% –93%), simple workup procedure and short reaction time (5 min).
Study of the Reactions of Fluorine‐Containing Amides with Aldehydes and the Structures of the Bisamides
Authors: ZHAO Jingwei , XIN Yong , YANG Jun , ZHU Shizheng , XU Liangzhong
Published: June 2009

The reactions of trifluoro or bromodifluoro acetamides with aromatic aldehydes in the presence of thionyl chloride and trifluoromethylsulfonic acid were investigated. Compared with the procedure reported previously, the yields were improved greatly and the reaction conditions were much milder. Both intra‐ and intermolecular weak interactions were discussed in detail based on the X‐ray diffraction analysis of 3aa and 3ab.
Synthesis, Characterization and Biological Activities of a New Fluorescent Indicator for the Intracellular Calcium Ions
Authors: HE Huaizhen , LEI Lei , LI Jianli , SHI Zhen
Published: June 2009

A novel calcium‐selective fluorescent indicator Fluo‐3M AM was synthesized by introduction of a methyl group into the Ca2+‐chelating moiety and adequately characterized by spectral methods (1H NMR, GC‐MS, IR and MALDI‐TOF MS). Meanwhile, its fluorescence spectra and some biological activities have been also studied. The results indicate that the new fluorescent indicator has relatively high affinity to calcium and a strong fluorescence signal, which should be useful for biomedical researchers to investigate the effects of calcium ions in biosystems.
Interpenetrating 2D Manganese(II) Coordination Polymer Supported by 4,4′‐Bis(dimethoxyphosphorylmethyl)‐biphenyl Ligands
Authors: ZHANG Xiangdong , GE Chunhua , YIN Jing , ZHAO Yang , HE Cui
Published: June 2009

A novel coordination polymer [Mn(bdpbp)2(NO3)2]n (1), where bdpbp=4,4′‐bis(dimethoxyphosphoryl‐ methyl)biphenyl, was prepared under mild condition. The structure has been determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses, IR spectra, luminescent property and thermogravimetric analyses. Structure of 1 exhibits infinite grid frameworks and forms two fold interpenetrating nets. Weak C–H···O hydrogen bonds ensure the formation and stability of a three dimensional supramolecular network.
Metabolic Syndrome Increases Mortality in Heart Failure
Authors: Tamariz Leonardo , Hassan Benjamin , Palacio Ana , Arcement Lee , Horswell Ron , Hebert Kathy
Published: June 2009

Background

Metabolic syndrome (MetS) is a risk factor for diabetes, cardiovascular disease, and heart failure, but little is known about the impact of MetS in patients who already have heart failure (HF).

Hypothesis

MetS increases mortality in HF.

Methods

We performed an analysis in 865 indigent HF patients enrolled in a HF disease management program at the Chabert Medical Center in Louisiana. All subjects were classified as having MetS if they met three or more of the National Cholesterol Education Program criteria. Mortality was defined using the Social Security Death Index. We calculated the relative hazard (RH) of death for those patients with and without MetS.

Results

The prevalence of MetS was 40% (95% confidence interval [CI]: 37–43). These subjects had similar ages (54.3±13.4 vs 55.7±12.8 years), more likely to be female (43% vs 33%), had similar baseline ejection fraction (31.4±9.7 vs 30.0±11.0), and New York Heart Association (NYHA) classification (2.20±0.9 vs 2.15±0.9). After 2.6±2.2 years of follow‐up 24% of the MetS group died compared to 16% in the non‐MetS group (p < 0.01). The RH of death for the MetS group was 1.5 (95% CI: 1.1–2.1) when compared to the non‐MetS group after adjustment demographics, use of angiotensin‐converting enzyme (ACE) inhibitor and β‐blocker, hematocrit, creatinine, educational level, and baseline ejection fraction.

Conclusions

The prevalence of MetS is high in indigent HF patients, and it increases the risk of death. Physicians treating patients with HF need to address the current MetS epidemic in HF. Copyright © 2009 Wiley Periodicals, Inc.
Transcatheter Aortic Valve Replacement: A Potential Option for the Nonsurgical Patient
Authors: Patel Jigar H. , Mathew Sunil T. , Hennebry Thomas A.
Published: June 2009

With improved life expectancy, the incidence of aortic stenosis is rising. However, up to one‐third of patients who require lifesaving surgical aortic valve replacement are denied surgery due to a high operative mortality rate. Such patients can only be treated with medical therapy or percutaneous aortic valvuloplasty, neither of which has been shown to improve mortality. With advances in interventional cardiology, transcatheter methods have been developed for aortic valve replacement. Clinical trials are investigating these devices in patients with severe aortic stenosis that have been denied surgery. Preliminary results from these trials suggest that transcatheter aortic valve replacement (TAVR) is not only feasible, but an effective way to improve symptoms. In this review, we describe the current technology and display available outcome data. Though technical challenges and operator learning curve limit optimal use of the current technology, continued experience and advancements in technology may one day make TAVR a viable alternative to traditional surgical aortic valve replacement. Copyright © 2009 Wiley Periodicals, Inc.
Two‐Year Outcomes of the Sirolimus‐Eluting Stent According to Unprotected Left Main Lesion
Authors: Kim Ung , Park Jong‐Seon , Seol Sang‐Hoon , Yang Tae‐Hyun , Kim Sung‐Man , Kim Dae‐Kyung , Kim Doo‐Il , Kim Dong‐Soo , Lee Won‐Jae , Lee Sang‐Hee , Hong Geu‐Ru , Shin Dong‐Gu , Kim Young‐Jo , Shim Bong‐Sup , Cho Yoon‐Kyung , Kim Hyung‐Seop , Nam Chang‐Wook , Hur Seung‐Ho , Kim Kwon‐Bae , Kim Yoon‐Nyun
Published: June 2009

Background

The data of long‐term outcomes of sirolimus‐eluting stent (SES) according to lesion location of unprotected left main coronary artery (LMCA) is scarce.

Hypothesis

The purpose of this study was to evaluate the long‐term outcomes after implantation of the SES in LMCA.

Methods

A total of 84 patients (51 males) who had undergone SES implantation for the treatment of native LMCA stenosis were enrolled. The patients were divided into 2 groups based on angiographic lesion location: those with significant stenosis in the ostium and/or body (group 1; n = 39) and those involving bifurcation (group 2; n = 45).

Results

All of the group 1 patients were treated with simple lesion coverage while different stenting techniques were used in group 2 (cross‐over: 44.8%, T: 6.7%, kissing: 37.8%, and crush techniques: 11.1%). The 8‐month quantitative angiographic findings and in‐hospital and 2 year rates of major adverse cardiac events (MACE) were compared between the 2 groups. Although angiographic success and in‐hospital MACE rates were similar in both groups with 1 cardiac death due to acute stent thrombosis in group 2, at 2‐year follow‐up, the MACE rate was significantly higher in group 2 than in group 1 at 2 years (22.2% vs 2.6%, respectively, P = 0.008). Coronary angiography revealed a significantly higher binary restenosis rate in group 2 compared with group 1 (20% vs 0%, respectively, P = 0.003).

Conclusions

Interventional treatment using SES in left main lesions showed favorable short‐term and long‐term outcomes in selected patients with lesion location being an important determinant of clinical and angiographic outcomes. Copyright © 2009 Wiley Periodicals, Inc.
Cataract Surgery — A Personal Account or “One Satisfied Patient”
Authors: Richard Conti C.
Published: June 2009

Most cataracts are related to aging. By age 80, more than half of all Americans either have a cataract or have experienced cataract surgery.

Although this editorial does not have any direct relationship to cardiovascular medicine, it may have some applicability with your patients, many of whom may be older rather than younger, and have cardiovascular disease in addition to visual problems perhaps due to cataracts. Copyright © 2009 Wiley Periodicals, Inc.
Adsorption of Selenium Using Bagasse Fly Ash
Authors: Wasewar Kailas L. , Prasad Basheshwar , Gulipalli Sekhararao
Published: June 2009

The present work involves the study of Se(IV) adsorption onto bagasse fly ash. The adsorbents were coated with a ferric chloride solution for the effective removal of selenium. The physico‐chemical characterization of the adsorbent was carried out using standard methods, e. g., proximate analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, thermo‐gravimetric analysis and differential thermal analysis. Batch experiments were carried out to determine the effect of various parameters such as adsorbent dose, initial pH, contact time, and temperature on the adsorption process. Results obtained from these studies were analyzed using various kinetic models and isotherms. Se(IV) adsorption onto adsorbent was high at low pH values, and decreased with an increase in initial pH. A temperature study showed that the uptake of Se(IV) was greatest at 293 K, within the temperature range studied. The parameters of pseudo first order, pseudo second order, and Weber‐Morris intra‐particle kinetic models were determined. Equilibrium isotherms were analyzed using Langmuir, Freundlich, and Temkin isotherms. Error analyses were also carried out using hybrid fractional error function and Marquardt's percent standard deviation.
Occurrence, Dynamics and Reactions of Organic Pollutants in the Indoor Environment
Authors: Salthammer Tunga , Bahadir Müfit
Published: June 2009

The indoor environment is a multidisciplinary scientific field involving chemistry, physics, biology, health sciences, architecture, building sciences and civil engineering. The need for reliable assessment of human exposure to indoor pollutants is attracting increasing attention. This, however, requires a detailed understanding of the relevant compounds, their sources, physical and chemical properties, dynamics, reactions, their distribution among the gas phase, airborne particles and settled dust as well as the availability of modern measurement techniques. Building products, furnishings and other indoor materials often emit volatile and semi‐volatile organic compounds. With respect to a healthy indoor environment, only low emitting products, which do not influence indoor air quality in a negative way, should be used in a building. Therefore, materials and products for indoor use need to be evaluated for their chemical emissions. This is routinely done in test cambers and cells. Many studies have shown that the types of sources in occupational and residential indoor environments, the spectrum of emitting compounds and the duration of emission cover a wide range. The demand for standardized test methods under laboratory conditions has resulted in several guidelines for determination of emission rates. Furthermore, it has now been recognized that both primary and secondary emissions may affect indoor air quality. The problem may become more dominant when components of different materials can react with each other or when catalytic materials are applied. Such products derived from indoor related reactions may have a negative impact on indoor air quality due to their low odor threshold, health related properties or the formation of ultrafine particles. Several factors can influence the emission characteristics and numerous investigations have shown that indoor chemistry is of particular importance for the indoor related characterization of building product emissions. This paper provides an overview of the current state of the art research on the mentioned topics.
Development of French Indoor Air Quality Guidelines
Authors: Mandin Corinne , Bonvallot Nathalie , Kirchner Séverine , Keirsbulck Marion , Alary René , Cabanes Pierre‐André , Dor Frédéric , Le Moullec Yvon , Mullot Jean‐Ulrich , Peel Anne‐Elisabeth , Rousselle Christophe
Published: June 2009

Indoor air quality guidelines (IAQGs) provide safe levels of indoor pollutant concentrations below which adverse health effects are not expected to occur in the general population, including susceptible subgroups. The French Agency for Environmental and Occupational Health Safety and the French Scientific and Technical Centre for Building have been leading a national working group to develop IAQGs based on health criteria. Firstly, a list of substances of concern was established for which IAQGs should be provided, and priority substances were identified. For each substance, toxicological and epidemiological data was reported and discussed. A critical effect and, if possible, a mode of action explaining the toxicity was described. Existing health based IAQGs already established and recommended by international groups or by some countries are collected, together with available toxicity reference values from the US Environmental Protection Agency, the Agency for Toxic Substances and Disease Registry, the California Office of Environmental Health Hazard Assessment, Health Canada and the Dutch Agency for Environmental Health. After an in‐depth analysis of these values, IAQGs are proposed. The production of an IAQG for a threshold pollutant (formaldehyde) and for a non‐threshold carcinogenic compound (benzene) are presented as examples.
Exposure Risk Assessment of the Emissions of Wood Preservative Chemicals in Indoor Environments
Authors: Yu Chuck , Crump Derrick , Brown Veronica
Published: June 2009

A collaborative study was undertaken to evaluate the sustainability of a new generation of biocides for the treatment of timbers in buildings and to validate the recyclability of the treated timbers. The evaluation included an assessment of the impact of emissions of the wood treatment chemicals during the service life of timbers and recycled wood based products. This involved emission testing of active substances (propiconazole, tebuconazole, permethrin and dichlofluanid) and volatile organic compounds (VOCs) from timber pretreated or coated using formulated products. The German AgBB method for evaluating VOC emissions from construction products was used to discuss the relative risk of the treated timbers. The emission rates of the active substances from the treated timbers were compared to the ADI (Acceptable Daily Intake) values given in the draft reports from the EU Biocides Directive, 98/8/EC, to determine the exposure risk to building occupants. As a part of this study, the emissions of the active substances from the stud frame of a newly built test cabin were monitored over a two year period.
Pharmacophore‐Based Discovery of Small‐Molecule Inhibitors of Protein–Protein Interactions between HIV‐1 Integrase and Cellular Cofactor LEDGF/p75
Authors: De Luca Laura , Barreca Maria Letizia , Ferro Stefania , Christ Frauke , Iraci Nunzio , Gitto Rosaria , Monforte Anna Maria , Debyser Zeger , Chimirri Alba
Published: June 2009

The cellular protein lens epithelium‐derived growth factor, or transcriptional coactivator p75 (LEDGF/p75), plays a crucial role in HIV integration. The protein–protein interactions (PPIs) between HIV‐1 integrase (IN) and its cellular cofactor LEDGF/p75 may therefore serve as targets for the development of new anti‐HIV drugs. In this work, a structure‐based pharmacophore model for potential small‐molecule inhibitors of HIV‐1 IN–LEDGF/p75 interaction was developed using the LigandScout software. The 3D model obtained was used for virtual screening of our in‐house chemical database, CHIME, leading to the identification of compound CHIBA‐3002 as an interesting hit for further optimization. The rational design, synthesis and biological evaluation of four derivatives were then carried out. Our studies resulted in the discovery of a new and more potent small molecule (7, CHIBA‐3003) that is able to interfere with the HIV‐1 IN–LEDGF/p75 interaction at micromolar concentration, representing one of the first compounds to show activity against these specific PPIs. Docking simulations were subsequently performed in order to investigate the possible binding mode of our new lead compound to HIV‐1 IN. This study is a valid starting point for the identification of anti‐HIV agents with a different mechanism of action from currently available antiviral drugs.
Anticancer Therapeutics. Edited by Sotiris Missailidis.
Authors: Foley David
Published: June 2009

Wiley–Blackwell, Chichester 2008. xix+424 pp., hardcover £ 85.00.—ISBN 978‐0‐470‐72303‐6

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Inside Cover: Silicon Analogues of the RXR‐Selective Retinoid Agonist SR11237 (BMS649): Chemistry and Biology (ChemMedChem 7/2009)
Authors: Lippert W. Peter , Burschka Christian , Götz Kathrin , Kaupp Martin , Ivanova Diana , Gaudon Claudine , Sato Yoshiteru , Antony Pierre , Rochel Natacha , Moras Dino , Gronemeyer Hinrich , Tacke Reinhold
Published: June 2009

The inside cover picture shows a carbon‐based (left) and the analogous silicon‐based (right) derivative of the highly potent pan‐RXR‐selective retinoid agonist SR11237. Switching from carbon to silicon increased the biological activity by a factor of ten. To further understand this effect, both agonists were co‐crystallized with the ligand‐binding domain of hRXRα (superposition of the two crystal structures shown). For more details, see the Full Paper by R. Tacke et al. on p. 1143 ff.

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Conditional relative survival of cancer patients and conditional probability of death
Authors: Bouvier Anne‐Marie , Remontet Laurent , Hédelin Guy , Launoy Guy , Jooste Valérie , Grosclaude Pascale , Belot Aurélien , Lacour Brigitte , Estève Jacques , Bossard Nadine , Faivre Jean
Published: June 2009

BACKGROUND:

Little information is available on the conditional probabilities of death among patients who survive for >5 years after a diagnosis with cancer. The objective of this study was to estimate the conditional probabilities of death for breast cancer, prostate cancer, colorectal cancer, and lung cancer in France.

METHODS:

The study included data from the French Network of Cancer Registries from 205,562 patients aged <75 years who were diagnosed with cancer between 1989 and 1997. The conditional probabilities of death were calculated by using a relative survival regression model in which age was included as a covariate.

RESULTS:

After the first year and until 10 years after diagnosis, the annual probability of death decreased dramatically for colorectal cancer: It was the same in all age groups after 3 years, and it was approximately 1% at 10 years. For prostate cancer, the decrease was not as great, and the conditional probability of death remained higher among younger patients at >4% at 10 years. During the 3 years after diagnosis, the probability of death was greater for older patients with breast cancer; then, it decreased less for younger patients compared with older patients, leading to a greater conditional probability of death among younger patients at 4 years and up to 10 years. The annual probability of death in patients with lung cancer decreased for both sexes but remained substantially higher for men than for women, reaching approximately 8% and 5%, respectively, at 10 years.

CONCLUSIONS:

Further studies would facilitate a better understanding of the observed differences in relative survival within European countries. Cancer 2009. © 2009 American Cancer Society.
Tamoxifen treatment and risk of deep venous thrombosis and pulmonary embolism
Authors: Hernandez Rohini K. , Sørensen Henrik Toft , Pedersen Lars , Jacobsen Jacob , Lash Timothy L.
Published: June 2009

BACKGROUND:

Tamoxifen therapy is reported to increase the risk of deep venous thrombosis and pulmonary embolism (DVT/PE). To the authors' knowledge, it is not yet known whether the risk changes with the amount of time elapsed since the initial tamoxifen prescription. This information would be valuable in identifying patients at high risk for DVT/PE.

METHODS:

The relation between timing of tamoxifen use and venous thromboembolism risk was examined. The study population of 16,289 women was identified from the clinical database of the Danish Breast Cancer Cooperative Group. It included women diagnosed with International Union Against Cancer (UICC) stage I or stage II estrogen receptor‐positive breast cancer between 1990 and 2004 at ages 45 to 69 years. Risks, risk ratios (RRs), and crude and adjusted hazards ratios were calculated for each of the first 5 years after breast cancer surgery and then cumulatively over the next 5 years.

RESULTS:

The 5‐year risk of DVT/PE was 1.2% for women receiving tamoxifen and 0.50% for women not receiving tamoxifen. Women treated with tamoxifen were at a higher risk for DVT/PE during the first 2 years after exposure (RR, 3.5; 95% confidence interval [95% CI], 2.1‐6.0). Subsequently, their risk was not found to be substantially increased (RR, 1.5; 95% CI, 0.88‐2.5). Older women taking tamoxifen appeared to be at higher risk than younger women during the first 2 years of exposure.

CONCLUSIONS:

The findings of the current study suggest that the first 2 years after the initiation of tamoxifen therapy may be the most crucial time for monitoring DVT/PE risk, particularly in older women. Cancer 2009. © 2009 American Cancer Society.
Radiotherapy planning complexity and survival after treatment of advanced stage lung cancer in the elderly
Authors: Goldsmith Benjamin , Cesaretti Jamie , Wisnivesky Juan P.
Published: June 2009

BACKGROUND:

Complex radiotherapy (RT) planning is increasingly common in the treatment of lung cancer, although it remains unclear if these treatments are associated with better outcomes. The authors evaluated the association between the complexity of RT planning simulation and survival among elderly patients with stage IIIB non‐small‐cell lung cancer (NSCLC).

METHODS:

The authors included all patients aged >65 years with histologically confirmed stage IIIB NSCLC diagnosed between 1992 and 2002 who were receiving chemotherapy and RT from the Surveillance, Epidemiology, and End Results registry linked to Medicare claims. Patients were divided into simple, intermediate, and complex RT planning groups using Medicare physician codes. Kaplan‐Meier curves and Cox regression were used to compare overall and lung cancer‐specific survival rates across groups.

RESULTS:

The authors identified 1733 patients: 148 (8%), 1138 (66%), and 447 (26%) were classified as having received simple, intermediate, and complex RT planning, respectively. Baseline characteristics were similar across groups. Increasing complexity of RT planning was significantly associated with better overall survival (P= .0002). Multivariate analyses showed that intermediate (hazards ratio [HR], 0.75; 95% confidence interval [95% CI], 0.62‐0.91) and complex planning (HR, 0.69; 95% CI, 0.55‐0.86) were associated with better overall survival compared with simple RT planning. Similar results were observed for lung cancer‐specific survival analyses. Toxicities were comparable across groups.

CONCLUSIONS:

The use of more complex RT planning and simulation methods is associated with better survival in elderly patients with stage IIIB NSCLC. Although these results should be further validated in prospective clinical trials, these data suggest that complex planning may improve the outcomes of these patients. Cancer 2009. © 2009 American Cancer Society.
Two‐soliton solutions to the three‐dimensional gravitational Hartree equation
Authors: Krieger Joachim , Raphaël Pierre , Martel Yvan
Published: June 2009

We construct nondispersive two‐soliton solutions to the three‐dimensional gravitational Hartree equation whose trajectories asymptotically reproduce the nontrapped dynamics of the gravitational two‐body problem. © 2009 Wiley Periodicals, Inc.
SERS Microscopy: Nanoparticle Probes and Biomedical Applications
Authors: Schlücker Sebastian
Published: June 2009

Microspectroscopic imaging: Surface‐enhanced Raman scattering (SERS) microscopy is a novel method of vibrational microspectroscopic imaging for the selective detection of biomolecules in targeted research. This review summarizes current designs of nanoparticle‐based SERS probes (see figure) and highlights first biomedical applications of SERS microscopy for protein localization ex and in vivo.

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Surface‐enhanced Raman scattering (SERS) microscopy is a novel method of vibrational microspectroscopic imaging for the selective detection of biomolecules in targeted research. This technique combines the advantages of biofunctionalized metal nanoparticles and Raman microspectroscopy for visualizing and quantifying the distribution of target molecules such as proteins in cells and tissues. Advantages of SERS over existing labeling approaches include the tremendous multiplexing capacity, quantification using the characteristic SERS signatures and high photostability. This review summarizes current designs of nanoparticle‐based SERS probes and highlights first biomedical applications of SERS microscopy for protein localization ex and in vivo.
Cover Picture: Structure, Dynamics and Optical Properties of Fluorescent Proteins: Perspectives for Marker Development (ChemPhysChem 9‐10/2009)
Authors: Nienhaus G. Ulrich , Wiedenmann Jörg
Published: June 2009

The cover picture displays the tentacles of the sea anemone Entacmaea quadricolor, a source of red fluorescent proteins. The 2‐imino‐5‐(4‐hydroxybenzylidene)‐imidazolinone chromophore (upper right) resides in the center of an 11‐stranded β‐barrel (lower left). The spectral properties of the fluorescent proteins depend on the conformation of the chromophore and its interactions with the surrounding protein scaffold. In the animal, the proteins form tight dimers or tetramers. Protein engineering yielded monomeric variants with optimized performance as protein tags in live cell imaging applications. On page 1369, G. U. Nienhaus and J. Wiedenmann review the structural diversity of GFP‐like proteins and discuss how structure and dynamics govern their optical properties and how they can be modified to create advanced marker proteins.

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Inside Cover: Stable, Non‐Destructive Immobilization of Native Nuclear Membranes to Micro‐Structured PDMS for Single‐Molecule Force Spectroscopy (ChemPhysChem 9‐10/2009)
Authors: Rangl Martina , Nevo Reinat , Liashkovich Ivan , Shahin Victor , Reich Ziv , Ebner Andreas , Hinterdorfer Peter
Published: June 2009

The investigation of native nuclear pore complexes (NPCs) with single‐molecule force spectroscopy requires stable and non‐destructive attachment of the nuclear envelope. Modified, micro‐structured PDMS turns out to be perfectly suited for membrane preparation as it preserves structure and function of the entire NPC, as shown on p. 1553 by A. Ebner et al.

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A Dendritic Oligothiophene Ruthenium Sensitizer for Stable Dye‐Sensitized Solar Cells
Authors: Sauvage Frédéric , Fischer Markus K. R. , Mishra Amaresh , Zakeeruddin Shaik M. , Nazeeruddin Mohammad K. , Bäuerle Peter , Grätzel Michael
Published: June 2009

We report a new type of dendritic terthiophene attached to a 2,2’‐bipyridine ligand for ruthenium‐based dye‐sensitized solar cells. As a result of the incorporation of this electron‐rich terthiophene donor unit into the heteroleptic ruthenium sensitizer [Ru(dcbpy)(3Tbpy)(NCS)2] (3T), the lowest‐energy metal‐to‐ligand charge transfer (MLCT) transition is red‐shifted and the molar extinction coefficient is increased compared to the analogous standard Z907Na sensitizer. A preliminary investigation of the 3T dye in combination with an iodine/iodide‐based electrolyte shows an interesting photovoltaic performance, with a maximum power conversion efficiency of 7.4 % measured under air mass 1.5 global sunlight irradiation. Accelerated testing of these devices at 60 °C under full sunlight soaking shows a remarkable stability over 1000 h.
The Free‐Radical Chemistry of Polyethylene Glycol: Organic Reactions in Compressed Carbon Dioxide
Authors: Wang Jin‐Quan , He Liang‐Nian , Miao Cheng‐Xia , Gao Jian
Published: June 2009

The thermal oxidative degradation of polyethylene glycol (PEG) is known to occur in an oxygen atmosphere at elevated temperatures. In this study, PEG radicals assumed to result from thermal oxidative degradation are successfully applied, in combination with compressed CO2, to initiate a range of free‐radical reactions, such as selective formylation of primary and secondary aliphatic alcohols, oxidation of benzylic alcohols, benzylic CC bond cleavage, and benzylic sp3 CH oxidation, demonstrating enormous synthetic potential in a cost‐efficient, practically useful, and environmentally friendly manner; not requiring any catalyst or additional free‐radical initiator. We find that both PEG and molecular oxygen are prerequisites in order to perform these reactions smoothly. Given that dense CO2 is immune to free‐radical chemistry; it is an ideal solvent for such reactions. As a result, compressed CO2 allows reactions initiated by PEG radicals to be tuned by subtly adjusting reaction parameters such as the CO2 pressure, thereby enhancing the product selectivity. By attaining a high selectivity towards the desired products this methodology is practical for organic syntheses.
A Design‐of‐Experiments Approach for the Optimization and Understanding of the Cross‐Metathesis Reaction of Methyl Ricinoleate with Methyl Acrylate
Authors: Ho Thao T. T. , Jacobs Tina , Meier Michael A. R.
Published: June 2009

A design‐of‐experiments approach for the investigation of the cross‐metathesis of methyl ricinoleate with methyl acrylate is described. Two second‐generation metathesis initiators were studied using different reaction conditions, revealing optimal reaction conditions for each catalyst. Interestingly, the two catalysts showed completely different temperature response profiles. As a result of these investigations, suitable reaction conditions for the sustainable production of two value‐added chemical intermediates were derived. Moreover, the design‐of‐experiments approach provided valuable information for a thorough understanding of catalytic reactions that would be more difficult to obtain by classic approaches.
FLSAC: A new scheme to defend against greedy behavior in wireless mesh networks
Authors: Djahel Soufiene , Naït‐Abdesselam Farid
Published: June 2009

The most commonly used medium access mechanism in wireless mesh networks is based on the CSMA/CA protocol. This protocol schedules properly the access to the medium among all the competing nodes. However, in a hostile environment, such as wireless mesh networks (WMNs), selfish or greedy behaving nodes may prefer to decline the proper use of the protocol rules in order to increase their bandwidth shares at the expense of the well‐behaving nodes. In this paper, we focus on such misbehavior and in particular on the adaptive greedy misbehavior of a node in the context of WMN environment. In such environment, wireless nodes compete to gain access to the medium and communicate with a mesh router (MR). In this case, a greedy node may violate the protocol rules in order to earn extra bandwidth share upon its neighbors. In order to avoid its detection, this node may adopt different techniques and switch dynamically between each of them. To counter such misbehavior, we propose to use a fuzzy logic‐based detection scheme. This scheme, dubbed FLSAC, is implemented in the MR/gateway to monitor the behavior of the attached wireless nodes and report any deviation from the proper use of the protocol. The simulation results of the proposed FLSAC scheme show robustness and its ability to detect and identify quickly any adaptive cheater. Copyright © 2009 John Wiley & Sons, Ltd.
An efficient vertical handoff scheme for microcellular and macrocellular interworking
Authors: Tansu F. , Salamah M.
Published: June 2009

The next generation wireless network environments increasingly become integrated to support anywhere, anytime connectivity for various applications like multimedia, full‐motion video and high data rates with appropriate quality of service (QoS). With these emerging needs, interworking of microcellular and macrocellular networks has been accompanied by service providers. However, these networks have different technologies, which make efficient vertical handoff a challenging issue. In this study, an efficient vertical handoff scheme (EVHS) for interworking between microcellular and macrocellular networks is proposed and analyzed. The handoff decision criteria of the proposed scheme include crucial features like user mobility, network conditions, pricing issues, and user preferences in addition to the received signal strength (RSS). EVHS ensures the selection of the most appropriate network in terms of cost and acceptable QoS according to users' preferences. The results show that EVHS scheme outperforms other proposed schemes in the literature in terms of incompletion probabilities, grade of service (GoS) and cost without causing degradation in system utilization. Besides, although EVHS scheme is mainly intended for user satisfaction, the results show that it does not cause a significant degradation in the revenue of the service provider. Copyright © 2009 John Wiley & Sons, Ltd.
Performance enhancement of mSCTP for vertical handover across heterogeneous wireless networks
Authors: Kim Dong Phil , Koh Seok Joo
Published: June 2009

In the mobile Stream Control Transmission Protocol (mSCTP) for vertical handover, a mobile user may suffer from performance degradation due to the problems of packet reordering and retransmission timeout and due to the packet loss during handover. To solve these problems, we propose a new scheme of handover retransmission for mSCTP handover, in which the correspondent node retransmits the outstanding data packets to the mobile node over the new primary path. From simulation results, it is shown that the proposed scheme can avoid the packet reordering and retransmission timeout problems during handover. Moreover, we can see that the proposed scheme can significantly improve throughput of mSCTP handover, compared with the existing schemes. Copyright © 2009 John Wiley & Sons, Ltd.
Epidemiology of diabetes in Asians of the Indian subcontinent
Authors: Ramaiya Kaushik L. , Kodali V. R. R. , Alberti K. G. M. M.
Published: June 2009

Asians from the Indian subcontinent have received greater attention in diabetes studies because of their migration in large numbers. The prevalence of non‐insulin‐dependent diabetes mellitus (NIDDM) in migrant Indians is higher than that in the population residing in the Indian subcontinent and is also usually higher than in the other racial groups in the host country. However, before drawing any conclusions with reference to the high prevalence of NIDDM in the migrant Indians, careful comparisons are required with more up‐to‐date information available from the Indian subcontinent itself. Recent data from India indeed indicate that the prevalence rates have either been underestimated in the past or are rising. The problem is compounded by the different diagnostic criteria used for defining diabetes. Some of the possible factors which cause variations in the rates of NIDDM in this population are discussed.
The scleroderma‐like syndrome of insulin‐dependent diabetes mellitus
Authors: Brik R. , Berant M. , Vardi P.
Published: June 2009

The scleroderma‐like syndrome (SLS) of diabetes consists of limited joint mobility and digital sclerosis. It is described in 8–50% of insulin‐dependent diabetes mellitus patients and is the earliest clinically apparent long‐term complication of diabetes in children and adolescents. The frequency of this finding appears to be related to the duration of diabetes and increasing age. Less clear are the relationships between this syndrome and glycaemic control or genetic factors. SLS is an easily identifiable marker for those young patients who may be at increased risk for the development of early microvascular complications. Recognition of this characterization will permit the clinician to focus, on newer and improved techniques for long‐term physiological control of the diabetes, in an attempt to prevent microvascular disease.
Synthesis and Photophysical Studies of a Pyrenylindole and a Phenalenoindole Obtained from Dehydroamino Acid Derivatives – Application as Fluorescent Probes for Biological Systems
Authors: Pereira Goreti , Abreu Ana S. , Castanheira Elisabete M. S. , Coutinho Paulo J. G. , Ferreira Paula M. T. , Queiroz Maria‐João R. P.
Published: June 2009

Two pyrenyl‐dehydroamino acid derivatives were cyclized by a metal‐assisted C–N intramolecular cyclization developed in our research group, to give a pyrenylindole and a phenalenoindole. The pyrenylindole was inserted into a peptide by solid‐phase coupling, with use of a 2‐chlorotrityl chloride resin and a Fmoc strategy. The photophysical properties of the pyrenylindole and phenalenoindole in several solvents were studied and showed that these compounds can be used as fluorescence probes. The results obtained with the peptide labelled with the pyrenylindole moiety show potential for use of this compound as a fluorescence label avoiding the aggregation propensity of pyrene compounds. Photophysical studies of the pyrenylindole and of the phenalenoindole in lipid membranes were also carried out. Steady‐state fluorescence anisotropy measurements revealed that both compounds adopt locations inside the lipid bilayers and are able to report the transition between the gel and liquid‐crystalline phases. The results point to potential use of these compounds as fluorescent probes for biological systems.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Probing the Mode of Asymmetric Induction of Biginelli Reaction Using Proline Ester Salts
Authors: Sohn Jeong‐Hun , Choi Hyun‐Moo , Lee Sunjung , Joung Seewon , Lee Hee‐Yoon
Published: June 2009

Described are the studies on the mechanism of the asymmetric Biginelli reaction using proline ester salt catalyst to explain the enantioselectivity of the 3,4‐dihydropyrimidin‐2(1H)‐one (DHPM) formation. Of the three possible activation methods by the catalyst that could provide asymmetric induction we revealed that the steric environment of the chiral enamine formed by the condensation of β‐keto ester with the catalyst is most responsible for the enantioselectivity. This assumption is supported by experiments with the N‐methylated catalyst, and the combination sets of L‐ or D‐proline ester catalyst with racemic or chiral BINOL‐derived phosphoric acid as counter acid. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Alternative Coupling Reaction with Unactivated Furan Derivatives
Authors: Giroux Marc‐André , Guérard Kimiaka C. , Beaulieu Marc‐André , Sabot Cyrille , Canesi Sylvain
Published: June 2009

Treatment of various dienimides in the presence of a Lewis acid and (trimethylsiloxy)furan leads to the corresponding aniline furan‐2(5H)‐ones. The same treatment with furan yields a triaryl product and, surprisingly, a byproduct with a pentacyclo[5.4.0.0.0.0]undecane main core. The formation of this birdcage system containing nine stereogenic centres was produced with complete diastereoselectivity.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Self‐Assembled Multilayers of Polyethylenimine and DNA: Spectrophotometric and Electrochemical Characterization and Application for the Determination of Acridine Orange Interaction
Authors: Ferreyra N. F. , Rivas G. A.
Published: June 2009

This work deals with the study of the interaction between acridine orange (AO) and calf‐thymus double stranded DNA (dsDNA) present in supramolecular architectures built on gold electrodes modified with mercapto‐1‐propanesulfonic acid (MPS) by self‐assembling of polyethylenimine and dsDNA. The optimal conditions for building the supramolecular architecture were obtained from UV‐vis spectrophotometric experiments. The electrochemical studies were performed by adsorptive transfer square wave voltammetry from the evaluation of the oxidation signal of AO accumulated within the multistructure. The effect of the number of PEI‐dsDNA bilayers (Au/MPS/(PEI‐dsDNA)n) on the accumulation and electrooxidation of AO is also discussed.
Rapid and Precise Coulometric Determination of Calcium Based on Electrolysis for Ion Transfer at the Aqueous|Organic Solution Interface
Authors: Kasuno Megumi , Kakitani Yuri , Shibafuji Yayoi , Okugaki Tomohiko , Maeda Kohji , Matsushita Takayuki , Kihara Sorin
Published: June 2009

A flow system was developed for the precise determination of Ca2+ based on the electrolytic ion transfer at the aqueous|1,2‐dichloroethane, W|DCE, interface. N,N,N′,N′‐tetraoctyl‐1,3‐oxapentanediamide was added to DCE to facilitate the transfer of Ca2+. The determination of Ca2+ could be achieved with an efficiency of 99.9±0.1% based on the coulomb number for the transfer of Ca2+. The coexistence of Mg2+, Na+, or K+ of concentration identical with that of Ca2+ did not give any interference. The interference from a large excess of Na+ was removed at another cell with DCE containing bis[(12‐crown‐4)methyl]‐2‐dodecyl‐2‐methylmalonate placed before the cell for the determination.
Feasibility of electrodialysis as a fast and selective sample preparation method for the profiling of low‐abundant peptides in biofluids
Authors: Kamphorst Jurre J. , Tjaden Ubbo R. , van der Heijden Rob , DeGroot Jeroen , van der Greef Jan , Hankemeier Thomas
Published: June 2009

Considerable interest exists in endogenous peptides as potential biomarkers, since they act as signaling molecules and are formed by degradation of proteins. A crucial step in the profiling of these peptides is the sample preparation, which aims to enrich the low‐abundant peptides, while removing interfering matrix compounds. In a feasibility study we examined the suitability of electrodialysis (ED) for this purpose. A custom‐made device was developed from the low‐binding material Kel‐F. It consisted of two compartments separated by a dialysis membrane, over which a voltage was applied. One compartment served as donor (containing the sample), while the smaller acceptor compartment collected the peptides. The procedure was optimized by investigating the effect of the applied voltage, ammonium acetate buffer concentration, and ED duration using model peptides. Optimum conditions were found at 300 V (150 V/cm), 25 mM ammonium acetate buffer (pH 3.8) containing 20% v/v DMSO, and 10 min, respectively. With these optimized parameters, recoveries for the model peptides were found to be 35–85% (average 64%). Additionally, ED was successfully applied to the challenging synovial fluid biological sample (due to its high viscosity). In a synovial fluid sample from a rheumatoid arthritis patient, 27 peptides originating from 12 proteins were identified, of which a considerable fraction was not identified before with other methods. This demonstrates the usefulness and complementary nature of combining ED with nanoLC‐MS for biomarker discovery. These results indicate that ED is promising as a fast and selective sample preparation method for the profiling of endogenous peptides.
Analysis of orange juice for total cysteine and glutathione content by CZE with UV‐absorption detection
Authors: Kubalczyk Paweł , Bald Edward
Published: June 2009

For total content of cysteine (Cys) and glutathione (GSH) a sample (500 μL) of neat orange juice or commercially available soft drinks is treated according to the procedure consisted of four essential steps: reduction of disulfide forms of the analytes to their thiol counterparts with Tris 2‐carboxyethylphosphine, derivatization of thiols to their S‐quinolinium derivatives with 2‐chloro‐1‐methylquinolinium tetrafluroborate, separation of so‐formed derivatives by capillary zone electrophoresis with ACN stacking, and detection and quantitation with the use of ultraviolet detector at 355 nm. Commercially available bare fused‐silica capillary served as the CE column. The method is linear in a wide range of concentrations covering practical application. The coefficient of correlation between analyte concentrations within the range from 2.5 to 30.0 μmol/L and the detector response was for Cys and GSH 0.998 and 0.997, respectively. The imprecision for above‐mentioned range was between 6.7 and 3.8, and 3.6 and 1.1% RSD for Cys and GSH, respectively. The method was applied to several samples of fresh juices and commercial orange beverages.