bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of the Built Environment on Mental and Sexual Health: Policy Implications and Recommendations
Authors: Satcher David , Okafor Martha , Dill LeConté J.
Published: June 2012

Research related to the intersection of the built environment and health has particularly flourished in the last decade. The authors highlight the theoretical and policy insights that have been made while also noting paucity in this literature as specifically related to mental and sexual health. Overall, the authors discuss policy implications of aspects of the built environment on both mental and sexual health behaviors and outcomes and suggest avenues for future research, program implementation, and policymaking for advancing health equity in these areas.
Large Scale Synthesis of Carbon Nanofibres on Sodium Chloride Support
Authors: Rajarao Ravindra , Bhat Badekai Ramachandra
Published: June 2012

Large scale synthesis of carbon nanofibres (CNFs) on a sodium chloride support has been achieved. CNFs have been synthesized using metal oxalate (Ni, Co and Fe) as catalyst precursors at 680 °C by chemical vapour deposition method. Upon pyrolysis, this catalyst precursors yield catalyst nanoparticles directly. The sodium chloride was used as a catalyst support, it was chosen because of its non-toxic and water soluble nature. Problems, such as the detrimental effect of CNFs, the detrimental effects on the environment and even cost, have been avoided by using a water soluble support. The structure of products was characterized by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The purity of the grown products and purified products were determined by the thermal analysis and X-ray diffraction method. Here we report the 7600, 7000 and 6500 wt% yield of CNFs synthesized over nickel, cobalt and iron oxalate. The long, curved and worm shaped CNFs were obtained on Ni, Co and Fe catalysts respectively. The lengthy process of calcination and reduction for the preparation of catalysts is avoided in this method. This synthesis route is simple and economical, hence, it can be used for CNF synthesis in industries.
Transactional sex and HIV: understanding the gendered structural drivers of HIV in fishing communities in Southern Malawi
Authors: MacPherson Eleanor E , Sadalaki John , Njoloma Macdonald , Nyongopa Victoria , Nkhwazi Lawrence , Mwapasa Victor , Lalloo David G , Desmond Nicola , Seeley Janet , Theobald Sally
Published: June 2012

Background

In Southern Malawi, the fishing industry is highly gendered, with men carrying out the fishing and women processing, drying and selling the fish. Research has shown that individuals living in fishing communities in low‐income countries are particularly vulnerable to HIV infection. One of the key drivers of HIV in fishing communities is transactional sex. In the fishing industry this takes the form of “fish‐for‐sex” networks where female fish traders exchange sex with fishermen for access to or more favourable prices of fish. By controlling the means of production, the power dynamics in these exchanges favour men and can make it more difficult for women to negotiate safe sex.

Methods

Qualitative methods were used to collect data on gendered drivers of transactional sex in the fishing community and how different groups perceive HIV risk in these transactions. Observation, focus group discussions and semi‐structured interviews were undertaken with members of the fishing communities, including men and women directly and indirectly involved in fishing.

Results

In fishing communities transactional sex was prevalent across a spectrum ranging from gift giving within relationships, to sex for fish exchanges, to sex worker encounters. Power differences between couples in transactional sexual encounters shape individual’s abilities to negotiate condom use (with women being at a particularly disadvantaged negotiating position). The context and motivations for transactional sex varied and was mediated by economic need and social position both of men and women. Female fish traders new to the industry and boat crew members who travelled for work and experienced difficult living conditions often engaged in transactional sex.

Conclusions

Transactional sex is common in Malawian fishing communities, with women particularly vulnerable in negotiations because of existing gendered power structures. Although knowledge and understanding of the HIV risk associated with transactional sex was common, this did not appear to result in the adoption of risk reduction strategies. This suggests that specially targeted strategies to increase women’s economic empowerment and tackle the structural drivers of women’s HIV risk could be important in fishing communities.
Individual and contextual factors influencing patient attrition from antiretroviral therapy care in an urban community of Lusaka, Zambia
Authors: Musheke Maurice , Bond Virginia , Merten Sonja
Published: June 2012

Introduction

Despite the relatively effective roll‐out of free life‐prolonging antiretroviral therapy (ART) in public sector clinics in Zambia since 2005, and the proven efficacy of ART, some people living with HIV (PLHIV) are abandoning the treatment. Drawing on a wider ethnographic study in a predominantly low‐income, high‐density residential area of Lusaka, this paper reports the reasons why PLHIV opted to discontinue their HIV treatment.

Methods

Opened‐ended, in‐depth interviews were held with PLHIV who had stopped ART (n = 25), ART clinic staff (n = 5), religious leaders (n = 5), herbal medicine providers (n = 5) and lay home‐based caregivers (n = 5). In addition, participant observations were conducted in the study setting for 18 months. Interview data were analysed using open coding first, and then interpreted using latent content analysis. The presentation of the results is guided by a social‐ecological framework.

Findings

Patient attrition from ART care is influenced by an interplay of personal, social, health system and structural‐level factors. While improved corporeal health, side effects and need for normalcy diminished motivation to continue with treatment, individuals also weighed the social and economic costs of continued uptake of treatment. Long waiting times for medical care and placing “defaulters” on intensive adherence counselling in the context of insecure labour conditions and livelihood constraints not only imposed opportunity costs which patients were not willing to forego, but also forced individuals to balance physical health with social integrity, which sometimes forced them to opt for faith healing and traditional medicine.

Conclusions

Complex and dynamic interplay of personal, social, health system and structural‐level factors coalesces to influence patient attrition from ART care. Consequently, while patient‐centred interventions are required, efforts should be made to improve ART care by extending and establishing flexible ART clinic hours, improving patient‐provider dialogue about treatment experiences and being mindful of the way intensive adherence counselling is being enforced. In the context of insecure labour conditions and fragile livelihoods, this would enable individuals to more easily balance time for treatment and their livelihoods. As a corollary, the perceived efficacy of alternative treatment and faith healing needs to be challenged through sensitizations targeting patients, religious leaders/faith healers and herbal medicine providers.
Synthesis of a Ni‐Containing Porous SiOC Material From Polyphenylmethylsiloxane by a Direct Foaming Technique
Authors: Idesaki Akira , Colombo Paolo
Published: June 2012

A Ni‐containing porous silicon oxycarbide (SiOC) material was produced from a blend of polyphenylmethylsiloxane (PPMS), azodicarbonamide (ADA) and nickel(II) acetylacetonate (Ni(acac)2) by a direct foaming technique. Homogeneous foaming of PPMS with well‐controlled macropore size distribution in the range of 0.1–0.5 mm was achieved, by controlling parameters such as the composition of starting mixture, the heating rate and the sample aspect ratio. A porous SiOC material with metallic Ni was obtained by pyrolysis below 900 °C in Ar. However, open porosity of the obtained porous SiOC was about only 37%. Therefore, the addition of fillers or an extraction treatment process were examined in order to obtain high levels of open, interconnected porosity. It was found that the extraction treatment of foamed PPMS by ethanol is effective in producing highly open porous SiOC ceramics. The Ni‐containing porous SiOC material synthesized by this treatment possessed an open porosity of about 70% and gas permeability constant of 4.10 × 10−10 m2 for k1 (Darcian permeability constant) and 3.17 × 10−6 m for k2 (non‐Darcian permeability constant). These values are sufficiently high for its application as a catalyst material. According to the results above, the synthesis of a Ni‐catalyst supported on a porous SiOC ceramic by a simple one‐pot process was demonstrated.
Controlling Surface Plasmon Optical Transmission with an Electrochemical Switch Using Conducting Polymer Thin Films
Authors: Baba Akira , Tada Kohji , Janmanee Rapiphun , Sriwichai Saengrawee , Shinbo Kazunari , Kato Keizo , Kaneko Futao , Phanichphant Sukon
Published: June 2012

Surface plasmon resonance (SPR)‐enhanced optical transmission is actively controlled by an electrochromism of conducting polymer thin films. Polyaniline and poly(3,4‐ethylenedioxythiophene) thin films are deposited on a thin gold grating surface. SPR‐enhanced optical transmission is demonstrated by irradiating white light on the conducting polymer thin film–gold grating surface and detecting the transmitted light from the back side. The transmission SPR system is combined with an electrochemical setup to manipulate the resonance. The wavelength of the sharp peak in the transmission light spectra is tuned by electrochemical doping/dedoping of the conducting polymer thin films. The present study of controllable SPR‐enhanced optical transmission should provide novel active plasmonic devices such as active bandpass filters or biosensors.
Probe‐Based Electro‐Oxidative Lithography of OTS SAMs Deposited onto Transparent ITO Substrates
Authors: Meroni Daniela , Ardizzone Silvia , Schubert Ulrich S. , Hoeppener Stephanie
Published: June 2012

Transparent conductive oxides like indium tin oxide (ITO) play a pivotal role in a wide range of innovative applications, such as new generations of solar cells. In many of these applications the tailoring of surface properties on the nanometer scale represents a highly desirable target. The local oxidation of self‐assembled monolayers (SAMs) using a scanning probe is a promising technique to achieve surface modifications on the nanometer scale. So far, electro‐oxidative lithography of SAMs has been reported mainly on Si wafers while there are no previous reports on transparent oxides. Here, we report the oxidative lithography of n‐octadecyltrichlorosilane (OTS) SAM deposited onto an ITO layer. A local overoxidation of the substrate is observed while the simultaneously occurring monolayer oxidation is indirectly confirmed by the site‐selective deposition of silver nanoparticles onto electro‐oxidized areas. The process of lithography is compared to that on OTS‐Si substrates and its mechanism is systematically investigated by means of scanning Kelvin probe microscopy (SKPM).
Discoidal Porous Silicon Particles: Fabrication and Biodistribution in Breast Cancer Bearing Mice
Authors: Godin Biana , Chiappini Ciro , Srinivasan Srimeenakshi , Alexander Jenolyn F. , Yokoi Kenji , Ferrari Mauro , Decuzzi Paolo , Liu Xuewu
Published: June 2012

Porous silicon (pSi) is emerging as a promising material in the development of nanovectors for the systemic delivery of therapeutic and imaging agents. The integration of photolithographic patterning, typical of the semiconductor industry, with electrochemical silicon etching provides a highly flexible strategy to fabricate monodisperse and precisely tailored nanovectors. Here, a microfabrication strategy for direct lithographic patterning of discoidal pSi particles is presented that enables precise and independent control over particle size, shape, and porous structure. Discoidal pSi nanovectors with diameters ranging from 500 to 2600 nm, heights from 200 to 700 nm, pore sizes from 5 to 150 nm, and porosities from 40 to 90% are demonstrated. The degradation in serum, interaction with immune and endothelial cells in vitro, and biodistribution in mice bearing breast tumors are assessed for two discoidal nanovectors with sizes of 600 nm × 400 nm and 1000 nm × 400 nm. It is shown that both particle types are degraded after 24 h of continuous gentle agitation in serum, do not stimulate cytokine release from macrophages or affect endothelial cell viability, and accumulate up to about 10% of the injected dose per gram tissue in orthotopic murine models of breast cancer. The accumulation of the discoidal pSi nanovectors into the breast tumor mass is found to be up to five times higher than for spherical silica beads with similar diameters.
Recent Progress in Aqueous Lithium‐Ion Batteries
Authors: Wang Yonggang , Yi Jin , Xia Yongyao
Published: June 2012

Building a low‐carbon society supported by sustainable energy is a worldwide topic. The aqueous lithium‐ion battery (LIB) has been demonstrated to be one of the most promising stationary power sources for sustainable energies such as wind and solar power. The aqueous LIB may solve both the safety problem associated with the lithium‐ion batteries which use highly toxic and flammable organic solvents, and the poor cycling life associated with commercialized aqueous rechargeable batteries including lead‐acid and nickel‐metal‐hydride systems. During the past decades, many efforts have been made to improve the performance of the aqueous lithium‐ion battery. The present work reviews the latest advances in the exploration and development of battery systems and relative materials. Also the main approaches, achievements, and challenges in this field are briefly commented on and discussed.
Carbon Nanotube‐Silicon Solar Cells
Authors: Tune Daniel D. , Flavel Benjamin S. , Krupke Ralph , Shapter Joseph G.
Published: June 2012

Due to the high cost of silicon photovoltaics there is currently great interest in finding alternative semiconductor materials for light harvesting devices. Single‐walled carbon nanotubes are an allotrope of carbon with unique electrical and optical properties and are promising as future photovoltaic materials. It is thus important to investigate the methods of exploiting their properties in photovoltaic devices. In addition to already extensive research using carbon nanotubes in organic photovoltaics and photoelectrochemical cells, another way to do this is to combine them with a relatively well understood model semiconductor such as silicon. Nanotube‐silicon heterojunction solar cells are a recent photovoltaic architecture with demonstrated power conversion efficiencies of up to ∼14% that may in part exploit the photoactivity of carbon nanotubes.
Use of pulsations to enhance the distribution of liquid injected into fluidized particles with commercial‐scale nozzles
Authors: Leach Aidan , Sabouni Rana , Berruti Franco , Briens Cedric
Published: June 2012

Gas‐atomized liquid injections into fluidized beds are commonly used in industrial processes such as fluid coking, fluid catalytic cracking (FCC), and pharmaceutical granulation, where it is important to optimize the distribution of the injected liquid to prevent the formation of unwanted liquid–solid agglomerates and maximize product yields. This injection is typically a two‐phase, gas‐atomized liquid injection. One issue with such a liquid injection is that most of the liquid is deposited at the end of the jet tip within the reactor. This study proposes introducing artificial fluctuations into the injection flow, which causes the jet penetration to vary, allowing for a more even spread of liquid throughout a fluidized bed reactor. The effect of artificial pulsations in the atomized injection, of various frequency and amplitude, was investigated in this study. Using pulsations, greatly enhanced the liquid distribution on the bed particles. © 2012 American Institute of Chemical Engineers AIChE J, 59: 719–728, 2013
A new syndrome of microtia with unilateral renal agenesis and short stature
Authors: Caglayan Ahmet Okay , Stevens Servi J.C. , Albrechts Jozefa C.M. , Dundar Munis , Engelen John
Published: June 2012

We report on a 13‐month‐old girl of first cousin parents who presented with a combination of short stature, bilateral microtia, proportionate short stature, distinctive facial features (bitemporal narrowing, long philtrum), and agenesis of the left kidney and a small right kidney. Clinical findings did not match any previously described syndromes with the anomalies seen in the patient. We performed SNP array analysis to characterize the observation as a novel syndrome and this was normal. We propose that this represents a new syndrome, likely of autosomal recessive inheritance. © 2012 Wiley Periodicals, Inc.
Heterozygous tandem duplication within the PTCH1 gene results in nevoid basal cell carcinoma syndrome
Authors: Kosaki Rika , Nagao Kazuaki , Kameyama Kohzoh , Suzuki Maiko , Fujii Katsunori , Miyashita Toshiyuki
Published: June 2012

Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by developmental defects and tumorigenesis. The gene responsible for NBCCS is PTCH1. Using multiplex ligation‐dependent probe amplification, we identified a heterozygous tandem duplication within the PTCH1 gene in a 14‐year‐old girl with typical NBCCS. We have sequenced the chromosomal breakpoint and determined the duplication as tandem in orientation and 18,814 bp in size. The fusion occurred between non‐repetitive elements with an overlap of three nucleotides. The duplicated segment began at exon 10 and ended at intron 17. Subsequent analysis of cDNA from the patient showed the expression of mutant mRNA species containing a duplicated segment spanning exons 11–17, resulting in a frameshift and premature stop codon. This is the first reported case of NBCCS due to a tandem multiexon duplication of PTCH1 representing a novel mechanism leading to the NBCCS phenotype, and highlights the importance of copy number analysis as an adjunct to exon sequencing in identifying infrequent mutational events in PTCH1. © 2012 Wiley Periodicals, Inc.
The Coffin–Siris syndrome: A proposed diagnostic approach and assessment of 15 overlapping cases
Authors: Schrier Samantha A. , Bodurtha Joann N. , Burton Barbara , Chudley Albert E. , Chiong Mary Anne D. , D'avanzo Maria Gabriella , Lynch Sally Ann , Musio Antonio , Nyazov Dmitriy M. , Sanchez‐Lara Pedro A. , Shalev Stavit A. , Deardorff Matthew A.
Published: June 2012

Coffin–Siris syndrome (CSS) is a rare, clinically heterogeneous disorder often considered in the setting of cognitive/developmental delay and 5th finger/nail hypoplasia. Due to the clinical variability of facial and other features, this diagnosis is often difficult to confirm clinically and the existence of this disorder as a specific diagnosis has been at times an issue of debate. In an effort to further delineate the spectrum and key phenotypic features, we reviewed 80 previously reported cases to define features in patients that most closely correlated with a convincing diagnosis. There appear to be two subtypes of CSS, one which displays the “classic” coarse facial features previously described; another displays “variant” facial features which are less striking. Using these features, we defined an algorithm to rank the confidence of diagnosis and applied it to 15 additional patients who had been previously characterized by chromosome microarray. This approach will also facilitate uniform categorization for whole‐exome analysis. © 2012 Wiley Periodicals, Inc.
Laryngeal malformation in Richieri‐Costa Pereira syndrome: New findings
Authors: Miguel Haline Coracine , Carneiro Christiano Giácomo , Tabith Alfredo , Zechi‐Ceide Roseli Maria , Genaro Katia Flores
Published: June 2012

Laryngeal structural anomalies were described in 13 cases of Richieri‐Costa Pereira syndrome, and four previously reported cases were reviewed. The 17 individuals examined had the typical laryngeal anomalies and vocal disorders previously described. The new findings are the laryngeal microweb observed in three cases and arytenoid anteriorization movement observed in 14 cases. © 2012 Wiley Periodicals, Inc.
Wheat flour fortification with folic acid: Changes in neural tube defects rates in Chile
Authors: Cortés Fanny , Mellado C. , Pardo R.A. , Villarroel L.A. , Hertrampf E.
Published: June 2012

In January 2000, Chilean Ministry of Health mandated the addition of folic acid (FA) to wheat flour in order to reduce the risk of neural tube defects (NTDs). This policy resulted in significant increases in serum and red cell folate in women of fertile age 1 year after fortification. To evaluate the effect of wheat flour fortification on the prevalence of NTDs in Chile we designed a prospective hospital‐based surveillance program to monitor the frequency of NTDs in all births (live and stillbirths) with birth weight ≥500 g at the nine public maternity hospitals of Santiago, Chile from 1999 to 2009. During the pre‐fortification period (1999–2000) the NTD rate was 17.1/10,000 births in a total of 120,566 newborns. During the post‐fortification period (2001–2009) the NTD rate decreased to 8.6/10,000 births in a total of 489,915 newborns, which translates into a rate reduction of 50% (RR: 0.5; 95% CI: 0.42–0.59) for all NTDs. The rate reduction by type of NTD studied was: 50% in anencephaly (RR: 0.5; 95% CI: 0.38–0.67), 42% in cephalocele (RR: 0.58; 95% CI: 0.37–0.89), and 52% in spina bifida (RR: 0.48; 95% CI: 0.38–0.6). Rates showed significant reduction both in stillbirths and live births: 510.3 to 183.6/10,000 (RR = 0.36; 95% CI: 0.25–0.53) and 13.3 to 7.5/10,000 (RR = 0.56; 95% CI: 0.47–0.68), respectively. In Chile, fortification of wheat flour with FA has proven to be an effective strategy for the primary prevention of NTDs. © 2012 Wiley Periodicals, Inc.
Antiepileptic drugs and pregnancy outcomes
Authors: Wlodarczyk Bogdan J. , Palacios Ana M. , George Timothy M. , Finnell Richard H.
Published: June 2012

The treatment of epilepsy in women of reproductive age remains a clinical challenge. While most women with epilepsy (WWE) require anticonvulsant drugs for adequate control of their seizures, the teratogenicity associated with some antiepileptic drugs (AEDs) is a risk that needs to be carefully addressed. Antiepileptic medications are also used to treat an ever broadening range of medical conditions such as bipolar disorder, migraine prophylaxis, cancer, and neuropathic pain. Despite the fact that the majority of pregnancies of WWE who are receiving pharmacological treatment are normal, studies have demonstrated that the risk of having a pregnancy complicated by a major congenital malformation is doubled when comparing the risk of untreated pregnancies. Furthermore, when AEDs are used in polytherapy regimens, the risk is tripled, especially when valproic acid (VPA) is included. However, it should be noted that the risks are specific for each anticonvulsant drug. Some investigations have suggested that the risk of teratogenicity is increased in a dose‐dependent manner. More recent studies have reported that in utero exposure to AEDs can have detrimental effects on the cognitive functions and language skills in later stages of life. In fact, the FDA just issued a safety announcement on the impact of VPA on cognition (Safety Announcement 6‐30‐2011). The purpose of this document is to review the most commonly used compounds in the treatment of WWE, and to provide information on the latest experimental and human epidemiological studies of the effects of AEDs in the exposed embryos. © 2012 Wiley Periodicals, Inc.
Clinical phenotype and candidate genes for the 5q31.3 microdeletion syndrome
Authors: Hosoki Kana , Ohta Tohru , Natsume Jun , Imai Sumiko , Okumura Akihisa , Matsui Takeshi , Harada Naoki , Bacino Carlos A. , Scaglia Fernando , Jones Jeremy Y. , Niikawa Norio , Saitoh Shinji
Published: June 2012

Array‐based technologies have led to the identification of many novel microdeletion and microduplication syndromes demonstrating multiple congenital anomalies and intellectual disability (MCA/ID). We have used chromosomal microarray analysis for the evaluation of patients with MCA/ID and/or neonatal hypotonia. Three overlapping de novo microdeletions at 5q31.3 with the shortest region of overlap (SRO) of 370 kb were detected in three unrelated patients. These patients showed similar clinical features including severe neonatal hypotonia, neonatal feeding difficulties, respiratory distress, characteristic facial features, and severe developmental delay. These features are consistent with the 5q31.3 microdeletion syndrome originally proposed by Shimojima et al., providing further evidence that this syndrome is clinically discernible. The 370 kb SRO encompasses only four RefSeq genes including neuregulin 2 (NRG2) and purine‐rich element binding protein A (PURA). NRG2 is one of the members of the neuregulin family related to neuronal and glial cell growth and differentiation, thus making NRG2 a good candidate for the observed phenotype. Moreover, PURA is also a good candidate because Pura‐deficient mice demonstrate postnatal neurological manifestations. © 2012 Wiley Periodicals, Inc.
First case of a Japanese girl with Myhre syndrome due to a heterozygous SMAD4 mutation
Authors: Asakura Yumi , Muroya Koji , Sato Takeshi , Kurosawa Kenji , Nishimura Gen , Adachi Masanori
Published: June 2012

This article reports the first case of a Japanese girl with molecularly confirmed Myhre syndrome (MS). The patient was 9 years old at her first visit, and she had been diagnosed with unknown skeletal dysplasia. Her phenotype fulfilled the clinical and radiological criteria for MS, such as typical facies with prognathism, hearing impairment, short stature, square body shape, and limited joint mobility. The thick calvarium and thick skin were clues to the clinical diagnosis of MS. A heterozygous mutation in the mothers‐against‐DPP homolog 4 (SMAD4) gene has been reported to cause MS. We sequenced SMAD4 using standard PCR‐based technique and identified a recurrent mutation (p.Ile500 Thr). She attained menarche before 11 years of age; however, she developed oligomenorrhea after a few years of 40‐day cycles, necessitating hormone replacement therapy. The luteinizing hormone‐releasing hormone (LHRH) tests suggested abnormalities related to hypothalamo‐hypophyseal malfunction. Previous reports on MS described early menarche in girls and early or delayed puberty and cryptorchidism in boys. Therefore, we recommend performing an endocrinological evaluation of the hypothalamo‐hypophyseal‐gonadal axis in patients with MS to clarify whether hormonal abnormalities are associated with the syndrome. © 2012 Wiley Periodicals, Inc.
Coherent phonon generation and detection in ultrathin SrTiO3 grown directly on silicon
Authors: Cen C. , Warusawithana M.P. , Levy J.
Published: June 2012

Time‐resolved two color pump‐probe polarization spectroscopy was performed at room temperature on SrTiO3 films grown directly on Si with film thickness varying from 2 nm to 7.8 nm. An E‐symmetry mode with a characteristic frequency of 0.2 THz is impulsively generated and measured in these coherently strained tetragonal phase SrTiO3 thin films. A superimposed exponentially decaying signal observed indicates the possible relaxational hopping of Ti ion between double potential wells. The dependence of the coherent phonon signal on pump and probe laser polarization helps to identify the symmetry of the phonon modes.
Inhibitoren für das konstitutive Proteasom und das Immunoproteasom: aktuelle und zukünftige Tendenzen in der Medikamentenentwicklung
Authors: Huber Eva Maria , Groll Michael
Published: June 2012

Proteolytischer Abbau ist ein essenzieller zellulärer Vorgang, der hauptsächlich durch das 20S‐Proteasomkernpartikel (CP), eine Protease von 720 kDa und 28 einzelnen Untereinheiten, bewerkstelligt wird. Wegen seiner zentralen Funktion ist das Proteasom ein vielversprechendes Angriffsziel für Wirkstoffe, das nach intensiven Untersuchungen im letzten Jahrzehnt mit der Zulassung von Bortezomib durch die US Food and Drug Administration (FDA) auch validiert worden ist. Gegenwärtig werden mehrere verbesserte Proteasominhibitoren der zweiten Generation in klinischen Studien als Krebswirkstoffe untersucht, und die meisten von ihnen hemmen sowohl das konstitutive Proteasom (cCP) als auch das Immunoproteasom (iCP). Allerdings scheint die selektive Inhibition des iCP, einer speziellen Proteasomklasse, die vorrangig in Immunzellen exprimiert wird, eine erfolgversprechende therapeutische Maßnahme für die Behandlung von Autoimmunerkrankungen zu sein. Auch wenn bereits wenige selektive Substanzen identifiziert worden sind, unterstützt die kürzlich bestimmte Kristallstruktur des iCP die Entwicklung und Optimierung iCP‐selektiver Verbindungen.
Effect of polymer in situ synthesized from methyl methacrylate and styrene on the morphology, thermal behavior, and durability of wood
Authors: YongFeng Li , XiaoYing Dong , ZeGuang Lu , WanDa Jia , YiXing Liu
Published: June 2012

A novel fast‐growing poplar wood, Populus ussuriensis Kom, was prepared into wood‐polymer composite by the in situ polymerization of methyl methacrylate and styrene through a vacuum/pressure and subsequent catalyst‐thermal process. scanning electron microscopy observation, FTIR, X‐ray diffraction, dynamic mechanical analysis, and thermogravimetric/derivative thermogravimetric analysis indicated that the resulted polymer well filled up wood cell lumen in an amorphous form and reinforced wood matrix, which resulted in the improvement of glass transition temperature, storage modulus, and thermal stability of wood. The decay resistance and dimensional stability of wood were also improved. Such wood‐based composite could be potentially used as reinforced material in construction fields. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Thermal storage nanocapsules by miniemulsion polymerization
Authors: de Cortazar Maider García , Rodríguez Raquel
Published: June 2012

Paraffin wax was nanoencapsulated by miniemulsion polymerization. Low solid content batch polymerizations were carried out and the influence of paraffin wax/methyl methacrylate ratio on polymeriztion kinetics, phase change properties, and thermal stability were investigated. Paraffin concentration controls the nucleation mechanism and nanocapsules particle size. The latent heat capacity increases as the content of encapsulated paraffin wax increases. The maximum amount of encapsulated paraffin wax achieved under the experimental conditions was 60 wt %, presenting a latent heat capacity of 140.3 J/g. Moreover, the encapsulated systems present in all cases better thermal stability than pure paraffin wax. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Uniform asymptotic estimates for ruin probabilities of renewal risk models with exponential Lévy process investment returns and dependent claims
Authors: Guo Fenglong , Wang Dingcheng
Published: June 2012

This paper investigates the ruin probabilities of a renewal risk model with stochastic investment returns and dependent claim sizes. The investment is described as a portfolio of one risk‐free asset and one risky asset whose price process is an exponential Lévy process. The claim sizes are assumed to follow a one‐sided linear process with independent and identically distributed step sizes. When the step‐size distribution is heavy tailed, we establish some uniform asymptotic estimates for the ruin probabilities of this renewal risk model. Copyright © 2012 John Wiley & Sons, Ltd.
Reflective writing as a tool for assessing teamwork in bioscience: Insights into student performance and understanding of teamwork
Authors: Mayne Lynne
Published: June 2012

To ensure a modern bioscience curriculum that responds to the current needs of stakeholders, there is a need to embed a range of generic capabilities that enables graduates to succeed in and contribute to a rapidly changing world, as well as building strong bioscience skills and knowledge. The curriculum must also prepare students for a rapidly evolving competitive work place and align with the needs of industry. This creates a challenge, how do we develop generic capabilities without losing discipline content. This report analyses teamwork projects embedded in an undergraduate Biotechnology degree designed to promote teamwork skills along with a deeper understanding of the underpinning biochemistry. Student reflective writing was used to capture students' understanding and experience of teamwork as well as provide insight into their metacognition. The analysis demonstrates that 73% of Year 3 and 93% of Year 4 students were capable of learning about teamwork through reflective writing. While the importance of frequent high quality communication was a common theme, evidence suggests that many students were unsophisticated in their use of communication software. The analysis also highlighted the depth of metacognition that underpins successful team function and the significant weaknesses in self‐insight some students possess. These findings challenge assumptions regarding student capacity for leadership and the ability of some students to contribute to successful team outcomes. It is essential for the design of teamwork experiences to fully understand the competencies that underlie teamwork, the metacognitive processes required, and ensure that assessments are fair and measure individual academic performance.
Athena: A hybrid management system for multi‐device educational content
Authors: Vásquez‐Ramírez Raquel , Alor‐Hernández Giner , Rodríguez‐González Alejandro
Published: June 2012

Over the past few years, a number of software applications have been proposed to tackle the administration, documentation, tracking, and reporting of training programs and contents such as CMS (Content Management System) and LMS (Learning Management System). However, CMS focuses on the administration and development of websites, while LMS is mainly focused on the management of training through the use of learning objects. CMS and LMS have features that can be used in conjunction in order to create educational environments which enhance the teaching–learning process in classrooms. This article presents a hybrid management system called Athena for multi‐device educational content providing a set of Web‐based interfaces for managing, presenting, and generating PHP‐based applications with educational content, reducing both the time and effort invested during the development process of this type of software. Athena borrows the main features of both CMS and LMS in order to manage and reuse educational content. Athena allows the user to develop platform‐independent multi‐device educational software using existing educational content. Athena aims to provide new forms of accessibility to educational content, envisioning a better future for online education. To demonstrate Athena's capabilities, we have presented a case study for generating a multi‐device physics course to emphasize our contribution.© 2012 Wiley Periodicals, Inc. Comput Appl Eng Educ 22:750–763, 2014; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21567
Achieving Regio‐ and Enantioselectivity of P450‐Catalyzed Oxidative CH Activation of Small Functionalized Molecules by Structure‐Guided Directed Evolution
Authors: Agudo Rubén , Roiban Gheorghe‐Doru , Reetz Manfred T.
Published: June 2012

Directed evolution of the monooxygenase P450‐BM3 utilizing iterative saturation mutagenesis at and near the binding site enables a high degree of both regio‐ and enantioselectivity in the oxidative hydroxylation of cyclohexene‐1‐carboxylic acid methyl ester. Wild‐type P450‐BM3 is 84 % regioselective for the allylic 3‐position with 34 % enantioselectivity in favor of the R alcohol. Mutants enabling R selectivity (>95 % ee) or S selectivity (>95 % ee) were evolved, while reducing other oxidation products and thus maximizing regioselectivity to >93 %. Control of the substrate‐to‐enzyme ratio is necessary for obtaining optimal and reproducible enantioselectivities, an observation which is important in future protein engineering of these mono‐oxygenases. An E. coli strain capable of NADPH regeneration was also engineered, simplifying directed evolution of P450 enzymes in general. These synthetic results set the stage for subsequent stereoselective and stereospecific chemical transformations to form more complex compounds, thereby illustrating the viability of combining genetically altered enzymes as catalysts in organic chemistry with traditional chemical methods.
Recurrent events after percutaneous closure of patent foramen ovale
Authors: Wallenborn Julia , Bertog Stefan C. , Franke Jennifer , Steinberg Daniel H. , Majunke Nicolas , Wilson Neil , Wunderlich Nina , Sievert Horst
Published: June 2012

Objectives

To determine the incidence of symptomatic recurrent embolic events after patent foramen ovale (PFO) closure and potential causes for these events.

Background

It is well‐known that cerebral or other embolic events may occur after PFO closure.

Methods

This is a retrospective analysis of consecutive patients who underwent PFO closure for secondary prevention of embolic events at a single institution.

Results

1,930 patients (mean age of 50 ± 13.3 years) underwent transcatheter PFO closure. Complete closure occurred in 92%. The annual recurrence rate of embolic events before PFO closure was 22.4% (785 events in 3,497 patient‐years). During follow‐up (mean 39 months), 63 recurrent events were documented: 25 strokes, 36 transient ischemic attacks (TIAs), and 2 peripheral embolic events. The overall annual recurrence rate after the procedure was 1% per year (63 events in 6,211 patient‐years). The majority of events occurred in patients without residual shunts (54/63). There was no significant association between the presence of a residual shunt and recurrent events [hazard ratio (HR) 1.7; 95% confidence interval (CI) 0.8–3.6, P = 0.16]. The most common cause for recurrent events was atherosclerosis. Nine out of 63 events were considered likely or possible paradoxical embolism due to residual shunt [stroke (2), TIA (5), and peripheral embolism (2)]. After PFO closure, the annual rate of events potentially related to paradoxical embolism was 0.14% (9 events in 6,211 patient‐years).

Conclusion

The incidence of symptomatic embolic events after PFO closure is low. Most recurrent events are related to coexistent conditions associated with thromboembolic risk rather than residual shunts. © 2012 Wiley Periodicals, Inc.
Ipsilateral arterial access for management of vascular complication in transcatheter aortic valve implantation
Authors: Frerker Christian , Schewel Dimitry , Kuck Karl‐Heinz , Schäfer Ulrich
Published: June 2012

Background

Transcatheter aortic valve implantation (TAVI) requires appropriate vascular access. Access site complications remain an important clinical issue. We report a new access site technique for management of puncture site visualization, reduction in use of contrast dye, in addition to several treatment options for management of vascular complications.

Methods

Between August 2008 and November 2011, a total of 323 high‐risk patients underwent a TAVI procedure at our institution. A new ipsilateral double‐puncture technique was used in 189 patients. In case of any vascular complication the distal puncture was intentionally used for retrograde balloon blocking or stent implantation.

Results

Overall mortality at 30 days was 8.7%. The rate of a major vascular complication was 7.1% (standard group 6.7% vs. double access group 7.4%, P = 0.59), resulting in death within 30 days in the standard group in 55.6% as compared to 21.4% in the double access group (P = 0.10), respectively. There was a numerical lower rate of surgical repair within the double access group as compared with the standard group (3.7% vs. 2.1%, P = 0.38). Occurrence of minor vascular complication was higher in the double access group (7.5% vs. 22.2%, P < 0.05). The use of contrast dye was significant lower with the new approach (200.9 ± 94.7 ml vs. 156.6 ± 79.0 ml, P < 0.05), resulting to a significant reduction of acute kidney injury (13.4% vs. 8.5%, P < 0.05). Occurrence of acute kidney injury was associated with a significantly higher 30‐day mortality (20.6% vs. 7.3%, P < 0.05) irrespective of the puncture technique used.

Conclusion

There was a significant reduction of acute kidney injury and contrast use with using the double access technique. The rate of minor vascular complication was higher within the double access group. In contrast, major vascular complication and subsequent surgical repair was numerically lower within the double access group. However, 30‐day mortality was statistically not different with using the double access technique. Performing a distal puncture to the principal access site serves as a safety net to economize the use of contrast dye and to maintain an open lumen for percutaneous treatment of a vascular complication. © 2012 Wiley Periodicals, Inc.
The Effects of Substituents and Solvents on the Ground‐State π‐Electronic Structure and Electronic Absorption Spectra of a Series of Model Merocyanine Dyes and Their Theoretical Interpretation
Authors: Mustroph Heinz , Reiner Knut , Senns Bianca , Mistol Jürgen , Ernst Steffen , Keil Dietmar , Hennig Lothar
Published: June 2012

Two series of new merocyanine dyes have been synthesised and the dependence of their electronic structure on substituents and solvents has been studied by NMR spectroscopy, by using both the NMR 13C chemical shifts between adjacent C atoms in the polymethine chain and the 3J(H,H) coupling constants for trans‐vicinal protons. The widely used valence bond (VB) model based on two contributing structures cannot account theoretically for the observed alternating π‐electron density in the polymethine chain. In addition, the prediction of zero‐π‐bond order alternation (or zero‐bond length alternation) by this model is also incorrect. However, the results are consistent with the predictions of a qualitative VB model which considers the resonance of a positive charge throughout the whole polymethine chain. Based on this model and the Franck‐Condon principle the effect of substituents and solvents on the fine structure of the electronic spectra of these dyes can be explained as vibronic transitions from the vibrational state v=0 to v′, where v is the vibrational quantum number of the totally symmetric CC valence vibration of the polymethine chain in the electronic ground state and v′ is that in the electronic excited state. In contrast, neither the effects of substituents or solvents on the electronic structure of merocyanines and their electronic spectra can be accounted for by the simple two state VB model.
Marilines A–C: Novel Phthalimidines from the Sponge‐Derived Fungus Stachylidium sp.
Authors: Almeida Celso , Hemberger Yasmin , Schmitt Sven Marcel , Bouhired Sarah , Natesan Lavanya , Kehraus Stefan , Dimas Konstantinos , Gütschow Michael , Bringmann Gerhard , König Gabriele M.
Published: June 2012

A marine‐derived fungus of the genus Stachylidium was isolated from the sponge Callyspongia cf. C. flammea. Chemical investigation of the bioactive fungal extract led to the isolation of the novel phthalimidine derivatives marilines A1 (1 a), A2 (1 b), B (2), and C (3). The absolute configurations of the enantiomeric compounds 1 a and 1 b were assigned by a combination of experimental circular dichroism (CD) investigations and quantum chemical CD calculations. The skeleton of marilines is most unusual, and its biosynthesis is suggested to require uncommon biochemical reactions in fungal secondary metabolism. Both enantiomers, marilines A1 (1 a) and A2 (1 b), inhibited human leukocyte elastase (HLE) with an IC50 value of 0.86 μM.
ZnO/Liquid Crystalline Nanohybrids: From Properties in Solution to Anisotropic Growth
Authors: Saliba Sarmenio , Coppel Yannick , Mingotaud Christophe , Marty Jean‐Daniel , Kahn Myrtil L.
Published: June 2012

Branched thermotropic liquid crystals (LCs) were successfully used as stabilizers for the synthesis of isotropic photoluminescent ZnO nanoparticles (NPs) in solution. 1H NMR spectroscopy and differential scanning calorimetry experiments demonstrate the existence of specific interactions between the LC and both the ZnO precursor and ZnO NPs. This offers the possibility for some branched molecules to act as structurally ordered hosts for the anisotropic growth of ZnO NPs.
Zeolite‐Supported Gold Nanoparticles for Selective Photooxidation of Aromatic Alcohols under Visible‐Light Irradiation
Authors: Zhang Xingguang , Ke Xuebin , Zhu Huaiyong
Published: June 2012

With new photocatalysts of gold nanoparticles supported on zeolite supports (Au/zeolite), oxidation of benzyl alcohol and its derivatives into the corresponding aldehydes can proceed well with a high selectivity (99 %) under visible‐light irradiation at ambient temperature. Au/zeolite photocatalysts were characterised by UV/Vis, X‐ray photoelectron spectroscopy (XPS), TEM, XRD, energy‐dispersive spectroscopy (EDS), Brauner–Emmet–Teller (BET) analyses, IR and Raman techniques. The surface plasmon resonance (SPR) effect of gold nanoparticles, the adsorption capability of zeolite supports and the molecular polarities of aromatic alcohols were demonstrated to have an essential correlation with the photocatalytic performances. In addition, the effects of light intensity, wavelength range and the role of molecular oxygen were investigated in detail. The kinetic study indicated that the visible‐light irradiation required much less apparent activation energy for photooxidation compared with thermal reaction. Based on the characterisation data and the photocatalytic performances, we proposed a possible photooxidation mechanism.
Chemical Components of Dendrobium chrysotoxum
Authors: Hu Jiangmiao , Fan Weiwei , Dong Fawu , Miao Zehong , Zhou Jun
Published: June 2012

Two new phenanthrenes, named chrysotoxols A and B (1, 2) and 24 known compounds were isolated from the stems of the accession species in 2010 Chinese Pharmacopoeia of "Shihu", Dendrobium chrysotoxum. All structures were elucidated by spectroscopic (NMR, MS, UV and IR) methods and the comparison with reported data in the literatures. Compound 2 and six known phenols were assessed for cytotoxic activity against two human tumor cell lines (A549 and HL‐60). The results indicated that erianin may have cytotoxic activity and the other six compounds lost activity at the concentration down to 10−5 mol·L−1.
Two New Cyclopeptides from Podocarpus nagi
Authors: Zhang Yi , Tang Chunping , Sob Sylvain Valère Tanemossu , Ke Changqiang , Ye Yang
Published: June 2012

Two new cyclopeptides, nagitides A and B, were isolated from the stem bark of Podocarpus nagi. Their structures were elucidated on the basis of NMR experiments including 1H‐1H COSY, HSQC, HMBC, ROESY, etc. This is the first report of cyclopeptides separated from this plant.
Sesquiterpenoids from Chloranthus spicatus
Authors: Yang Shengping , Chen Huadong , Yue Jianmin
Published: June 2012

Five new sesquiterpenoids (1–5), namely chlospicates A–E (1–5), along with ten known sesquiterpenoids and three known sesquiterpenoid dimers, were isolated from the whole plant of Chloranthus spicatus. Their structures were elucidated on the basis of spectroscopic data.