bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgical Site Infection Complicating Breast Cancer Surgery in Kuwait
Authors: Omar Abeer A. , Al-Mousa Haifaa H.
Published: December 2012

Background and Objectives. Surgical site infection (SSI) is the most common postoperative complication associated with breast cancer surgery. The present investigation aimed to determine the SSI rate after breast cancer surgeries and the causative microorganisms. Patients and Methods. All patients who underwent breast surgery in Kuwait Cancer Control Center as a treatment for breast cancer from January 2009–December 2010 were prospectively followed for the development of SSI. Indirect detection was used to identify SSIs through medical record to review and discussion with the treating surgeons. Results. The number of operations was 438. Females represented 434 (99.1%) cases while males constituted only 4 (0.9%) cases. SSIs were diagnosed after 10 operations, all for female cases. Most of the SSIs (8 cases; 80%) were detected after patients were discharged, during outpatient followup. Out of those 5/8; (62.5%) were readmitted for management of SSI. Nine patients (90%) received systemic antibiotic therapy for management of their wound infection. The SSI rate was 2.3%. The main causative organism was Staphylococcus aureus (S. aureus) which was responsible for 40% of infections. Gram negative bacteria were isolated from 40% of the cases. Conclusion. SSI is an important complication following breast cancer surgery. Microbiological diagnosis is an essential tool for proper management of such patients.
Prevalence of Treatment Failure among Pulmonary Tuberculosis Patients in Federal Medical Centre, Gombe, Northeastern Nigeria
Authors: Jibrin Y. B. , Ali A. B. , Saad S. T. , Kolo P. M.
Published: December 2012

Treatment failure in patients with pulmonary tuberculosis poses a great danger to the global effort in control of tuberculosis. This study evaluated prevalence of treatment failure among pulmonary tuberculosis patients at Federal Medical Centre (FMC) Gombe, Nigeria. Consecutive patients managed between August 2008 and August 2009 at the Directly Observed Therapy (Tuberculosis) Unit of our hospital were enrolled for the study. Sputum specimens were collected from each patient at entry for Acid Fast Bacilli and repeated at the end of 2nd, 5th and 7th month of treatment. Of the 247 patients recruited, 200 patients consisting of 118 (59%) males and 82 (41%) females aged 15–78 years with a mean of 36.8 ± 12.4 years completed the study. One hundred and fifteen (57.5%) of the patients were sputum smear positive at entry while 85 (42%) were negative. Among 115 smear positive patients at baseline, 80 patients (69.6%), 26 (22.6%) and 24 (20.9%) remained positive after 2nd, 5th and 7th month of treatment respectively. In conclusion, there is a high treatment failure rate (22.6%) among our TB patients; and this poses a great danger to healthcare personnel and close contacts in the community.
Detection of Fetal Aneuploidies by QF-PCR in Transcervical Cell Samples
Authors: Cioni Riccardo , Bussani Cecilia , Di Tommaso Mariarosaria
Published: December 2012

Objective. To evaluate the accuracy in the diagnosis of aneuploidies of a quantitative fluorescent polymerase chain reaction (QF-PCR) assay on trophoblastic cells recovered from transcervical cells samples (TCCs) collected by intrauterine lavage (IUL). Study Design. DNA analysis was performed on cells of seemingly trophoblastic origin isolated from IUL samples collected prior to first trimester termination of pregnancy. The analysis was performed by multiplex QF-PCR, using a panel of 29 polymorphic short tandem repeats (STRs) for the chromosomes X, Y, 21, 13, and 18. Results. The QF-PCR analysis on placental samples revealed that among the three cases studied there were two cases of trisomy 21 and one case of monosomy X; the comparison of peak profiles obtained from IUL, placental, and maternal samples confirmed the diagnosis of aneuploidy in all three cases. Conclusion. This study suggests that the detection of chromosomal aneuploidies in micromanipulated TCC samples can be achieved by QF-PCR amplification of selected highly polymorphic and chromosome specific markers. With respect to standard karyotype, QF-PCR analysis has the limitation that only numerical abnormalities of selected chromosomes can be detected but retains the advantages of being quicker, less expensive, and less lab demanding.
The Role of Sulfhydryl Reactivity of Small Molecules for the Activation of the KEAP1/NRF2 Pathway and the Heat Shock Response
Authors: Dinkova-Kostova Albena T.
Published: December 2012

The KEAP1/NRF2 pathway and the heat shock response are two essential cytoprotective mechanisms that allow adaptation and survival under conditions of oxidative, electrophilic, and thermal stress by regulating the expression of elaborate networks of genes with versatile protective functions. The two pathways are independently regulated by the transcription factor nuclear factor-erythroid 2 p45-related factor 2 (NRF2) and heat shock factor 1 (HSF1), respectively. The activity of these transcriptional master regulators increases during conditions of stress and also upon encounter of small molecules (inducers), both naturally occurring as well as synthetically produced. Inducers have a common chemical property: the ability to react with sulfhydryl groups. The protein targets of such sulfhydryl-reactive compounds are equipped with highly reactive cysteine residues, which serve as sensors for inducers. The initial cysteine-sensed signal is further relayed to affect the expression of large networks of genes, which in turn can ultimately influence complex cell fate decisions such as life and death. The paper summarizes the multiple lines of experimental evidence demonstrating that the reactivity with sulfhydryl groups is a major determinant of the mechanism of action of small molecule dual activators of the KEAP1/NRF2 pathway and the heat shock response.
Endoplasmic Reticulum Stress: Its Role in Disease and Novel Prospects for Therapy
Authors: Schönthal Axel H.
Published: December 2012

The endoplasmic reticulum (ER) is a multifunctional organelle required for lipid biosynthesis, calcium storage, and protein folding and processing. A number of physiological and pathological conditions, as well as a variety of pharmacological agents, are able to disturb proper ER function and thereby cause ER stress, which severely impairs protein folding and therefore poses the risk of proteotoxicity. Specific triggers for ER stress include, for example, particular intracellular alterations (e.g., calcium or redox imbalances), certain microenvironmental conditions (e.g., hypoglycemia, hypoxia, and acidosis), high-fat and high-sugar diet, a variety of natural compounds (e.g., thapsigargin, tunicamycin, and geldanamycin), and several prescription drugs (e.g., bortezomib/Velcade, celecoxib/Celebrex, and nelfinavir/Viracept). The cell reacts to ER stress by initiating a defensive process, called the unfolded protein response (UPR), which is comprised of cellular mechanisms aimed at adaptation and safeguarding cellular survival or, in cases of excessively severe stress, at initiation of apoptosis and elimination of the faulty cell. In recent years, this dichotomic stress response system has been linked to several human diseases, and efforts are underway to develop approaches to exploit ER stress mechanisms for therapy. For example, obesity and type 2 diabetes have been linked to ER stress-induced failure of insulin-producing pancreatic beta cells, and current research efforts are aimed at developing drugs that ameliorate cellular stress and thereby protect beta cell function. Other studies seek to pharmacologically aggravate chronic ER stress in cancer cells in order to enhance apoptosis and achieve tumor cell death. In the following, these principles will be presented and discussed.
Lesotho's Minimum PMTCT Package: lessons learned for combating vertical HIV transmission using co‐packaged medicines
Authors: McDougal Lotus , Moteetee Mpolai M , Mohai Florence , Mphale Malisebo , Mahanty Binod , Motaung Blandinah , Ankrah Victor , Reynolds Makaria , Legins Kenneth , Tiam Appolinaire , Luo Chewe , McClure Craig , Binkin Nancy
Published: December 2012

Introduction

Mother‐to‐child transmission of HIV can be reduced to<5% with appropriate antiretroviral medications. Such reductions depend on multiple health system encounters during antenatal care (ANC), delivery and breastfeeding; in countries with limited access to care, transmission remains high. In Lesotho, where 28% of women attending ANC are HIV positive but where geographic and other factors limit access to ANC and facility deliveries, a Minimum PMTCT Package was launched in 2007 as an alternative to the existing facility‐based approach. Distributed at the first ANC visit, it packaged together all necessary pregnancy, delivery and early postnatal antiretroviral medications for mother and infant.

Methods

To examine the availability, feasibility, acceptability and possible negative consequences of the Minimum PMTCT Package, data from a 2009 qualitative and quantitative study and a 2010 facility assessment were used. To examine the effects on ANC and facility‐based delivery rates, a difference‐in‐differences analytic approach was applied to 2009 Demographic and Health Survey data for HIV‐tested women who gave birth before and after Minimum PMTCT Package implementation.

Results

The Minimum PMTCT Package was feasible and acceptable to providers and clients. Problems with test kit and medicine stock‐outs occurred, and 46% of women did not receive the Minimum PMTCT Package until at least their second ANC visit. Providing adequate instruction on the use of multiple medications represented a challenge. The proportion of HIV‐positive women delivering in facilities declined after Minimum PMTCT Package implementation, although it increased among HIV‐negative women (difference‐in‐differences=14.5%, p=0.05). The mean number of ANC visits declined more among HIV‐positive women than among HIV‐negative women after implementation, though the difference was not statistically significant (p=0.09). Changes in the percentage of women receiving≥4 ANC visits did not differ between the two groups.

Conclusions

If supply issues can be resolved and adequate client educational materials provided, take‐away co‐packages have the potential to increase access to PMTCT commodities in countries where women have limited access to health services. However, efforts must be made to carefully monitor potential changes in ANC visits and facility deliveries, and further evaluation of adherence, safety and effectiveness are needed.
A new command governor architecture for transient response shaping
Authors: Yucelen Tansel , Johnson Eric
Published: December 2012

In this paper, we develop a control framework for stabilization and command following of nonlinear uncertain dynamical systems. The proposed methodology consists of a new command governor architecture and an adaptive controller. The command governor is a dynamical system that adjusts the trajectory of a given command to follow an ideal reference system capturing a desired closed‐loop dynamical system behavior in transient time. Specifically, we show that the controlled nonlinear uncertain dynamical system can approach the ideal reference system by choosing the design parameter of the command governor. In addition, an adaptive element is used to asymptotically assure that the error between the controlled nonlinear uncertain dynamical system and the ideal reference system is reduced in long term. Therefore, the proposed methodology not only has closed‐loop transient and steady‐state performance guarantees but can also shape the transient response by adjusting the trajectory of the given command with the command governor. We highlight that there exists a trade‐off between the adaptive controller's learning rate and the command governor's design parameter. This key feature of our framework allows rapid suppression of system uncertainties without resorting to a high learning rate in the adaptive controller. Furthermore, we discuss the robustness properties of the proposed approach with respect to high‐frequency dynamical system content such as measurement noise and ∕ or unmodeled dynamics. A numerical example is provided to demonstrate the efficacy of the proposed architecture. Copyright © 2012 John Wiley & Sons, Ltd.
Spin of a Nanotech Spin‐Off
Authors: Ozin Geoffrey A.
Published: December 2012

Innovation in advanced technology often springs from ideas birthed in universities yet the attitudes of professors and their students towards entrepreneurship and their stance on the collision between fundamental research in the pursuit of knowledge and applied research directed to the creation of intellectual property, inventions, companies, jobs, products, and wealth, is not that well appreciated either inside or outside our universities. In this article I will explore this interesting issue and try to gain some insight into the challenges faced by professors confronted by the challenge of transforming basic science and engineering knowledge into products in the market place, using nanotechnology as a case study. While the specific focus of this article is on nanotechnology, more generic issues are also raised that relate to transformational business development and entrepreneurship in society and universities in a larger sense.
Core/Shell PbSe/PbS QDs TiO2 Heterojunction Solar Cell
Authors: Etgar Lioz , Yanover Diana , Čapek Richard Karel , Vaxenburg Roman , Xue Zhaosheng , Liu Bin , Nazeeruddin Mohammad Khaja , Lifshitz Efrat , Grätzel Michael
Published: December 2012

Quasi type‐II PbSe/PbS quantum dots (QDs) are employed in a solid state high efficiency QD/TiO2 heterojunction solar cell. The QDs are deposited using layer‐by‐layer deposition on a half‐micrometer‐thick anatase TiO2 nanosheet film with (001) exposed facets. Theoretical calculations show that the carriers in PbSe/PbS quasi type‐II QDs are delocalized over the entire core/shell structure, which results in better QD film conductivity compared to PbSe QDs. Moreover, PbS shell permits better stability and facile electron injection from the QDs to the TiO2 nanosheets. To complete the electrical circuit of the solar cell, a Au film is evaporated as a back contact on top of the QDs. This PbSe/PbS QD/TiO2 heterojunction solar cell produces a light to electric power conversion efficiency (η) of 4% with short circuit photocurrent (Jsc) of 17.3 mA/cm2. This report demonstrates highly efficient core/shell near infrared QDs in a QD/TiO2 heterojunction solar cell.
Dendron‐Stabilized Liquid Crystalline Blue Phases with an Enlarged Controllable Range of the Photonic Band for Tunable Photonic Devices
Authors: Shibayama Seishi , Higuchi Hiroki , Okumura Yasushi , Kikuchi Hirotsugu
Published: December 2012

Liquid crystalline blue phases (BPs) show excellent potential for application in tunable photonic devices because they possess the unique optical property that the selective 3D Bragg diffraction in a visible wavelength region can be continuously shifted using an electric field. A new approach to simultaneously extend the wavelength range of field‐induced Bragg diffraction shift and the temperature range of thermodynamically stable BPs is critically needed. Here, a new BP material system is shown using a dendron molecule to extend simultaneously the two BP ranges. One is the temperature range of thermodynamically stable BPs, which is expanded from 2.1 to 4.6 °C. The other is the reversible maximum shift range of Bragg wavelength on the electric field, which is extended from 85 to 109 nm. The physical mechanism of the dendron‐stabilizing effect in BPs is discussed in terms of elastic property and orientational order of liquid crystal molecules.
Components Simulation of Viral Envelope via Amino Acid Modified Chitosans for Efficient Nucleic Acid Delivery: In Vitro and In Vivo Study
Authors: Chang Jing , Xu Xianghui , Li Haiping , Jian Yeting , Wang Gang , He Bin , Gu Zhongwei
Published: December 2012

Novel nonviral gene vectors of alkaline amino acids such as arginine‐ (Arg), histidine‐ (His), and lysine‐ (Lys) modified chitosans (AAA‐CSs) are developed to simulate the components of viral envelopes to enhance transfection efficiency. The structures of the modified chitosans are characterized using 1H NMR spectroscopy. Acid‐base titration results indicate that the modified chitosans exhibit strong buffering capacity. The morphology of the AAA‐CSs/pDNA complexes is observed by use of transmission electron microscopy and atomic force microscopy. The complexes are spherical nanoparticles with a mean size around 100 nm. Zeta potential tests reveal that the complexes are positively charged and their zeta potentials vary from +0.1 to +19.5 mV. The MTT assay and agarose gel electrophoresis demonstrate that the AAA‐CSs are non‐cytotoxic and have excellent DNA condensation and protection abilities. Cellular uptake investigation of the AAA‐CSs/pDNA complexes demonstrates that Arg‐CS and His‐CS have better cellular internalization property than the unmodified chitosan. The in vitro gene transfection is evaluated in HEK293 and NIH3T3 cell lines and in vivo transfection is carried out in tibialis anterior muscles. The results reveal that the arginine‐modified chitosan could significantly enhance gene‐transfection efficiency both in vitro and in vivo.
Synthesis of Hierarchically Porous Hydrogen Silsesquioxane Monoliths and Embedding of Metal Nanoparticles by On‐Site Reduction
Authors: Moitra Nirmalya , Kanamori Kazuyoshi , Shimada Toyoshi , Takeda Kazuyuki , Ikuhara Yumi H. , Gao Xiang , Nakanishi Kazuki
Published: December 2012

A facile synthesis of a new class of reactive porous materials is reported: hierarchically porous hydrogen silsesquioxane (HSiO1.5, HSQ) monoliths with well‐defined macropores and mesopores. The HSQ monoliths are prepared via sol‐gel accompanied by phase separation in a mild condition, and contain micrometer‐sized co‐continuous macropores and high specific surface area reaching up to 800 m2 g−1 because of the small mesopores. A total preservation of Si–H, which is always an issue of HSQ materials, is confirmed by 29Si solid‐state NMR. The HSQ monolith has then been subjected to reduction of noble metal ions to their corresponding metal nanoparticles in simple aqueous solutions under an ambient condition. The nanoparticles produced in this manner are immobilized on the HSQ monolith and are characterized by X‐ray diffraction (XRD) and high angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM). Both the bare HSQ and nanoparticles‐embedded HSQ are promising as heterogeneous catalysts, exhibiting reusability and recyclability.
Migrant and seasonal crop worker injury and illness across the northeast
Authors: Scribani Melissa , Wyckoff Sherry , Jenkins Paul , Bauer Henry , Earle‐Richardson Giulia
Published: December 2012

Background

Northeast farmworkers are a small, widely dispersed, and isolated population. Little is known about their occupational injury and illness risk.

Methods

Researchers conducted chart reviews in migrant health centers across the Northeast, and calculated incidence‐density for agricultural morbidity based on a new method for estimating total worker hours at risk, and adjusting for cases seen at other sources of care.

Results

An estimated annual average of 1,260 cases translated to an incidence of 30.27 per 10,000 worker weeks, (12.7 per 100 FTEs). Straining/spraining events (56% cases) was the most common occurrence (16.8 per 10,000 worker weeks), and lifting (21.5% cases) was the leading contributing factor. Incidence by crop category ranged from 12.95 (ground crop) to 29.69 (bush crop) per 10,000 weeks. Only 2.8% filed for Workers' Compensation.

Conclusion

The predominance of straining/spraining events affecting the back, and their association with lifting suggests that Northeastern farmworker occupational health programs should focus on ergonomics, and specifically on safe lifting. Am. J. Ind. Med. 56:845–855, 2013. © 2012 Wiley Periodicals, Inc.
Functional links between canine height and jaw gape in catarrhines with special reference to early hominins
Authors: Hylander William L.
Published: December 2012

This study tests the hypothesis that decreased canine crown height in catarrhines is linked to (and arguably caused by) decreased jaw gape. Associations are characterized within and between variables such as upper and lower canine height beyond the occlusal plane (canine overlap), maximum jaw gape, and jaw length for 27 adult catarrhine species, including 539 living subjects and 316 museum specimens. The data demonstrate that most adult male catarrhines have relatively larger canine overlap dimensions and gapes than do conspecific females. For example, whereas male baboons open their jaws maximally more than 110% of jaw length, females open about 90%. Humans and hylobatids are the exceptions in that canine overlap is nearly the same in both the sexes and so is relative gape (ca. 65% for humans and 110% for hylobatids). A correlation analysis demonstrates that a large portion of relative gape (maximum gape/projected jaw length) is predicted by relative canine overlap (canine overlap/jaw length). Relative gape is mainly a function of jaw muscle position and/or jaw muscle‐fiber length. All things equal, more rostrally positioned jaw muscles and/or shorter muscle fibers decrease gape and increase bite force during the power stroke of mastication, and the net benefit is to increase the mechanical efficiency during chewing. Similarly, more caudally positioned muscles and/or longer muscle fibers increase the amount of gape and decrease bite force. Overall, the data support the hypothesis that canine reduction in early hominins is functionally linked to decreased gape and increased mechanical efficiency of the jaws. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.
Generation of EUV radiation by plasmonic field enhancement using nano‐structured bowties and funnel‐waveguides
Authors: Park In‐Yong , Choi Joonhee , Lee Dong‐Hyub , Han Seunghwoi , Kim Seungchul , Kim Seung‐Woo
Published: December 2012

Recent experimental data of high‐order harmonic generation (HHG), obtained by use of the plasmonic field enhancement of nanostructure bowties and funnel‐waveguides, are presented. Emphasis is laid on reproduction of previous experimental results and also elucidation of the fundamental limitations associated with the nanostructure thermal damage, small laser‐gas interaction volume, and atomic line emission in the plasmon‐driven HHG process. In addition, the dominance of coherent harmonics is quantitatively verified by implementing a two‐beam interference experiment using a pair of funnel‐waveguides. This study proves that funnel‐waveguides are a superior plasmonic device capable of providing not only high thermal immunity but also sufficient atom emitters to produce practically usable extreme‐ultraviolet (EUV) radiation in a reproducible manner.
Observers in spacetime and nonlocality
Authors: Mashhoon Bahram
Published: December 2012

Characteristics of observers in relativity theory are critically examined. For field measurements in Minkowski spacetime, the Bohr‐Rosenfeld principle implies that the connection between actual (i.e., noninertial) and inertial observers must be nonlocal. Nonlocal electrodynamics of non‐uniformly rotating observers is discussed and the consequences of this theory for the phenomenon of spin‐rotation coupling are briefly explored.
Synthetic polymers and their potential as genetic materials
Authors: Pinheiro Vitor B. , Loakes David , Holliger Philipp
Published: December 2012

DNA and RNA are the only known natural genetic materials. Systematic modification of each of their chemical building blocks (nucleobase, sugar, and phosphate) has enabled the study of the key properties that make those nucleic acids genetic materials. All three moieties contribute to replication and, significantly, all three moieties can be replaced by synthetic analogs without loss of function. Synthetic nucleic acid polymers capable of storing and propagating information not only expand the central dogma, but also highlight that DNA and RNA are not unique chemical solutions for genetic information storage. By considering replication as a question of information transfer, we propose that any polymer that can be replicated could serve as a genetic material.

Editor's suggested further reading in BioEssays Xenobiology: A new form of life as the ultimate biosafety tool Abstract
Mitochondria, maternal inheritance, and asymmetric fitness: Why males die younger
Authors: Wolff Jonci N. , Gemmell Neil J.
Published: December 2012

Mitochondrial function is achieved through the cooperative interaction of two genomes: one nuclear (nuDNA) and the other mitochondrial (mtDNA). The unusual transmission of mtDNA, predominantly maternal without recombination is predicted to affect the fitness of male offspring. Recent research suggests the strong sexual dimorphism in aging is one such fitness consequence. The uniparental inheritance of mtDNA results in a selection asymmetry; mutations that affect only males will not respond to natural selection, imposing a male‐specific mitochondrial mutation load. Prior work has implicated this male‐specific mutation load in disease and infertility, but new data from fruit flies suggests a prominent role for mtDNA in aging; across many taxa males almost invariably live shorter lives than females. Here we discuss this new work and identify some areas of future research that might now be encouraged to explore what may be the underpinning cause of the strong sexual dimorphism in aging.

Editor's suggested further reading in BioEssays: Mitonuclear match: Optimizing fitness and fertility over generations drives ageing within generations Abstract

Mitochondrial manoeuvres: Latest insights and hypotheses on mitochondrial partitioning during mitosis in Saccharomyces cerevisiae Abstract

Mitochondria and the culture of the Borg Abstract
Bacterial cooperation in the wild and in the clinic: Are pathogen social behaviours relevant outside the laboratory?
Authors: Harrison Freya
Published: December 2012

Individual bacterial cells can communicate via quorum sensing, cooperate to harvest nutrients from their environment, form multicellular biofilms, compete over resources and even kill one another. When the environment that bacteria inhabit is an animal host, these social behaviours mediate virulence. Over the last decade, much attention has focussed on the ecology, evolution and pathology of bacterial cooperation, and the possibility that it could be exploited or destabilised to treat infections. But how far can we really extrapolate from theoretical predictions and laboratory experiments to make inferences about ‘cooperative’ behaviours in hosts and reservoirs? To determine the likely importance and evolution of cooperation ‘in the wild’, several questions must be addressed. A recent paper that reports the dynamics of bacterial cooperation and virulence in a field experiment provides an excellent nucleus for bringing together key empirical and theoretical results which help us to frame – if not completely to answer – these questions.
Modeling and optimization of granulation process of activated sludge in sequencing batch reactors
Authors: Su Kui‐Zu , Ni Bing‐Jie , Yu Han‐Qing
Published: December 2012

Aerobic granulation is a promising process for wastewater treatment, but this granulation process is very complicated and is affected by many factors. Thus, a mathematical model to quantitatively describe such a granulation process is highly desired. In this work, by taking into account all of key steps including biomass growth, increase in particle size and density, detachment, breakage and sedimentation, an one‐dimensional mathematic model was developed to simulate the granulation process of activated sludge in a sequencing batch reactor (SBR). Discretization methodology was applied by dividing operational time, sedimentation process, size fractions and slices into discretized calculation elements. Model verification and prediction for aerobic granulation process were conducted under four different conditions. Four parameters indicative of granulation progression, including mean radius, biomass discharge ratio, total number, and bioparticle size distribution, were predicted well with the model. An optimum controlling strategy, automatically adjusted of settling time, was also proposed based on this model. Moreover, aerobic granules with a density higher than 120 g VSS/L and radius in a range of 0.4–1.0 mm were predicted to have both high settling velocity and substrate utilization rate, and the corresponding optimum operating conditions were be determined. Experimental results demonstrate that the developed model is appropriate for simulating the formation of aerobic granules in SBRs. These results are useful for designing and optimizing the cultivation and operation of aerobic granule process. Biotechnol. Bioeng. 2013; 110: 1312–1322. © 2012 Wiley Periodicals, Inc.
Construction of an inducible cell‐communication system that amplifies Salmonella gene expression in tumor tissue
Authors: Dai Yumei , Toley Bhushan J. , Swofford Charles A. , Forbes Neil S.
Published: December 2012

Bacterial therapies have the potential to overcome resistances that cause chemotherapies to fail. When using bacteria to produce anticancer agents in tumors, triggering gene expression is necessary to prevent systemic toxicity. The use of chemical triggers, however, is hampered by poor delivery of inducing molecules, which reduces the number of activated bacteria. To solve this problem, we created a cell‐communication system that enables activated bacteria to induce inactive neighbors. We hypothesized that introducing cell communication into Salmonella would improve direct triggering strategies by increasing protein production, increasing sensitivity to inducer molecules, and enabling expression in tumor tissue. To test these hypotheses we integrated the PBAD promoter into the quorum‐sensing machinery from Vibrio fischeri. The expression of a fluorescent reporter gene was compared to expression from non‐communicating controls. Function in three‐dimensional tissue was tested in a tumor‐on‐a‐chip device. Bacterial communication increased fluorescence 40‐fold and increased sensitivity to inducer molecules more than 10,000‐fold. The system enabled bacteria to activate neighbors and increased the time‐scale of protein production. Gene expression was controllable and tightly regulated. At the optimal inducing signal, communicating bacteria produced 350 times more protein than non‐communicating bacteria. The cell‐communication system created in this study has uses beyond cancer therapy, including protein manufacturing, bioremediation and biosensing. It would enable amplified induction of gene expression in any environment that limits availability of inducer molecules. Ultimately, because inducible cellular communication enables gene expression in tissue, it will be a critical component of bacterial anticancer therapies. Biotechnol. Bioeng. 2013; 110: 1769–1781. © 2012 Wiley Periodicals, Inc.
Comparative characterization of novel ene‐reductases from cyanobacteria
Authors: Fu Yilei , Castiglione Kathrin , Weuster‐Botz Dirk
Published: December 2012

The growing importance of biocatalysis in the syntheses of enantiopure molecules results from the benefits of enzymes regarding selectivity and specificity of the reaction and ecological issues of the process. Ene‐reductases (ERs) from the old yellow enzyme family have received much attention in the last years. These flavo‐enzymes catalyze the trans‐specific reduction of activated CC bonds, which is an important reaction in asymmetric synthesis, because up to two stereogenic centers can be created in one reaction. However, limitations of ERs described in the literature such as their moderate catalytic activity and their strong preference for NADPH promote the search for novel ERs with improved properties. In this study, we characterized nine novel ERs from cyanobacterial strains belonging to different taxonomic orders and habitats. ERs were identified with activities towards a broad spectrum of alkenes. The reduction of maleimide was catalyzed with activities of up to 35.5 U mg−1 using NADPH. Ketoisophorone and (R)‐carvone, which were converted to the highly valuable compounds (R)‐levodione and (2R,5R)‐dihydrocarvone, were reduced with reaction rates of up to 2.2 U mg−1 with NADPH. In contrast to other homologous ERs from the literature, NADH was accepted at moderate to high rates as well: Enzyme activities of up to 16.7 U mg−1 were obtained for maleimide and up to 1.3 U mg−1 for ketoisophorone and (R)‐carvone. Additionally, excellent stereoselectivities were achieved in the reduction of (R)‐carvone (97–99% de). In particular, AnabaenaER3 from Anabaena variabilis ATCC 29413 and AcaryoER1 from Acaryochloris marina MBIC 11017 were identified as useful biocatalysts. Therefore, novel ERs from cyanobacteria with high catalytic efficiency were added to the toolbox for the asymmetric reduction of alkenes. Biotechnol. Bioeng. 2013; 110: 1293–1301. © 2012 Wiley Periodicals, Inc.
Pathways of reductive 2,4‐dinitroanisole (DNAN) biotransformation in sludge
Authors: Olivares Christopher , Liang Jidong , Abrell Leif , Sierra‐Alvarez Reyes , Field Jim A.
Published: December 2012

As the use of the insensitive munition compound 2,4‐dinitroanisole (DNAN) increases, releases to the environment may pose a threat to local ecosystems. Little is known about the environmental fate of DNAN and the conversions caused by microbial activity. We studied DNAN biotransformation rates in sludge under aerobic, microaerophilic, and anaerobic conditions, detected biotransformation products, and elucidated their chemical structures. The biotransformation of DNAN was most rapid under anaerobic conditions with H2 as a cosubstrate. The results showed that the ortho nitro group in DNAN is regioselectively reduced to yield 2‐methoxy‐5‐nitroaniline (MENA), and then the para nitro group is reduced to give 2,4‐diaminoanisole (DAAN). Both MENA and DAAN were identified as important metabolites in all redox conditions. Azo and hydrazine dimer derivatives formed from the coupling of DNAN reduction products in anaerobic conditions. Secondary pathways included acetylation and methylation of amine moieties, as well as the stepwise O‐demethylation and dehydroxylation of methoxy groups. Seven unique metabolites were identified which enabled elucidation of biotransformation pathways. The results taken as a whole suggest that reductive biotransformation is an important fate of DNAN leading to the formation of aromatic amines as well as azo and hydrazine dimeric metabolites. Biotechnol. Bioeng. 2013; 110: 1595–1604. © 2012 Wiley Periodicals, Inc.
Introduction to spin label electron paramagnetic resonance spectroscopy of proteins
Authors: Melanson Michelle , Sood Abha , Török Fanni , Török* Marianna
Published: December 2012

An undergraduate laboratory exercise is described to demonstrate the biochemical applications of electron paramagnetic resonance (EPR) spectroscopy. The β93 cysteine residue of hemoglobin is labeled by the covalent binding of 3‐maleimido‐proxyl (5‐MSL) and 2,2,5,5‐tetramethyl‐1‐oxyl‐3‐methyl methanethiosulfonate (MTSL), respectively. The excess spin label is removed by gel‐exclusion chromatography. Changes in the mobility of the reporter groups attached to the protein are monitored by EPR spectroscopy. While the spectral parameters of the rigidly attached 5‐MSL provide information on the rotation of the whole spin labeled protein, MTSL bound by a more flexible linkage describes the local environment of the cysteine residue in the interior of the protein structure. Students can study the known crystal structure of hemoglobin in comparison to the results they obtain by analyzing the EPR spectra. Overall, the exercise introduces them to laboratory techniques such as protein labeling, gel filtration, EPR spectroscopy, as well as familiarizes them with the online Protein Data Bank as a research resource and PyMOL software as a structure visualization tool. © 2013 by The International Union of Biochemistry and Molecular Biology, 41(3):156–162, 2013
Asymmetric Hydrogenation Using Rhodium Complexes Generated from Mixtures of Monodentate Neutral and Anionic Phosphorus Ligands
Authors: Frank Dominik J. , Franzke Axel , Pfaltz Andreas
Published: December 2012

A series of monodentate neutral and anionic phosphorus ligands was synthesized and evaluated in the asymmetric rhodium‐catalyzed hydrogenation of functionalized olefins by using either catalysts containing identical ligands or catalysts generated from mixtures of two different ligands. We expected that the combination of an anionic ligand with a neutral ligand would favor the formation of hetero over homo bis‐ligand complexes due to charge repulsion. NMR spectroscopic studies confirmed that charge effects can indeed shift the equilibrium toward the hetero bis‐ligand complexes. In several cases, the combination of a neutral phosphane with an anionic phosphane, one chiral and the other achiral, furnished significantly higher enantioselectivities than analogous mixtures of two neutral ligands. The best results were obtained with a mixture of an anionic phosphoramidite and a neutral phosphoric acid diester. It is supposed that in this case a hydrogen bond between the two ligands additionally stabilizes the hetero ligand combination.
Hierarchical Self‐Assembly of a Biomimetic Light‐Harvesting Antenna Based on DNA G‐Quadruplexes
Authors: Sancho Oltra Núria , Browne Wesley R. , Roelfes Gerard
Published: December 2012

A new modular approach to an artificial light‐harvesting antenna system is presented. The approach involves the hierarchical self‐assembly of porphyrin acceptor molecules to G‐quadruplexes tethered to coumarin donor moieties.
Boronate Ligands in Materials: Determining Their Local Environment by Using a Combination of IR/Solid‐State NMR Spectroscopies and DFT Calculations
Authors: Sene Saad , Reinholdt Marc , Renaudin Guillaume , Berthomieu Dorothée , Zicovich‐Wilson Claudio M. , Gervais Christel , Gaveau Philippe , Bonhomme Christian , Filinchuk Yaroslav , Smith Mark E. , Nedelec Jean‐Marie , Bégu Sylvie , Mutin P. Hubert , Laurencin Danielle
Published: December 2012

Boronic acids (R‐B(OH)2) are a family of molecules that have found a large number of applications in materials science. In contrast, boronate anions (R‐B(OH)3−) have hardly been used so far for the preparation of novel materials. Here, a new crystalline phase involving a boronate ligand is described, Ca[C4H9‐B(OH)3]2, which is then used as a basis for the establishment of the spectroscopic signatures of boronates in the solid state. The phase was characterized by IR and multinuclear solid‐state NMR spectroscopy (1H, 13C, 11B and 43Ca), and then modeled by periodic DFT calculations. Anharmonic OH vibration frequencies were calculated as well as NMR parameters (by using the Gauge Including Projector Augmented Wave—GIPAW—method). These data allow relationships between the geometry around the OH groups in boronates and the IR and 1H NMR spectroscopic data to be established, which will be key to the future interpretation of the spectra of more complex organic–inorganic materials containing boronate building blocks.
Enantioselective Ring Opening of meso‐Epoxides with Aromatic Amines Catalyzed by Dinuclear Magnesium Complexes
Authors: Bao Hongli , Wang Zheng , You Tianpa , Ding Kuiling
Published: December 2012

The dinuclear magnesium complexes generated in situ from the reaction of chiral multidentate semi‐azacrown ether ligands with n‐Bu2Mg were found to be efficient catalysts for enantioselective ring‐opening of meso‐epoxides with aniline derivatives, affording the corresponding chiral β‐amino alcohols in good yields with up to 90% ee.
Stereoselective Synthesis of (−)‐Chloramphenicol, (+)‐Thiamphenicol and (+)‐Sphinganine via Chiral Tricyclic Iminolactone
Authors: Li Qiong , Zhang Hongbo , Li Chenguang , Xu Pengfei
Published: December 2012

The stereoselective syntheses of (−)‐chloramphenicol, (+)‐thiamphenicol and (+)‐sphinganine are described. The two continuous chiral centers within three target molecules were constructed through aldol reaction of chiral tricyclic iminolactone and aldehyde.
Field Evaluation of Arid Soils Wetting Pattern in Subsurface Drip Irrigation Scheme
Authors: Al‐Mefleh Naji K. , Abu‐Zreig Majed
Published: December 2012

A field study evaluating wetted radius (Wr), downward depth (Dd), and upward movement (Um) under different emitter discharges and lateral depths was conducted. Four emitter discharges (2, 4, 8, and 16 L/h) and four lateral depths (0, 10, 20, and 30 cm) were tested in a clay loam soil. Relationships were found between the emitter discharge and lateral depth versus Wr, Dd, and Um. Wetting area at the surface occurs under different emitter discharges and lateral depths except at 30 cm lateral depth. At lateral depth of 0 and 10 cm, Wr and emitter discharge were positively correlated. The Dd was not affected by emitter discharge except for laterals installed at 20 cm depth. At 30 cm lateral depth, the correlations between each of Wr, Um, and Dd with emitter discharge were poor. The ratios of Wr/Dd and Um/Dd, with respect to emitter position, were less than unity over different emitter discharges and lateral depths. These results shed some light on the design of subsurface drip irrigation scheme so that the spacing between emitters should be determined based on the lateral depths and discharge of emitters. Evaporation losses were negligible for the 30‐cm‐lateral depth since the upward moisture movement has not reached the soil surface area at all discharge rates tested in the study.
Multifocal breast cancer documented in large‐format histology sections
Authors: Pekar Gyula , Hofmeyer Syster , Tabár László , Tarján Miklós , Chen Tony Hsiu‐Hsi , Yen Amy Ming‐Fang , Chiu Sherry Yueh‐Hsia , Hellberg Dan , Gere Mária , Tot Tibor
Published: December 2012

BACKGROUND:

The prognostic significance of molecular phenotype in breast cancer is well established in the literature. Recent studies have demonstrated that subgross lesion distribution (unifocal, multifocal, and diffuse) and disease extent also carry prognostic significance in this disease. However, the correlation of molecular phenotypes with subgross parameters has not yet been investigated in detail.

METHODS:

In total, 444 consecutive invasive breast cancers that were documented in large‐format histology slides and worked up with detailed radiologic‐pathologic correlation were sampled into tissue microarray blocks and stained immunohistochemically to delineate the molecular subtypes.

RESULTS:

Diffuse or multifocal distribution of the invasive component of breast carcinomas in this series was associated with a 4.14‐fold respectively 2.75‐fold risk of cancer‐related death compared with unifocal tumors irrespective of molecular phenotype. Patients who had human epidermal growth factor receptor 2 (HER2)‐positive cancers; estrogen receptor‐negative, progesterone receptor‐negative, and HER2‐negative (triple‐negative) cancers; or basal‐like cancers had a 2.18‐fold, 2.33‐fold, and 4.07‐fold risk of dying of disease, respectively, compared with patients who had luminal A carcinomas. Unifocal luminal A, HER2‐positive, and basal‐like cancers were associated with significantly better long‐term survival outcomes than their multifocal or diffuse counterparts; luminal B and triple‐negative tumors also had the same tendency. In multivariate analysis, patient age, tumor size category, lymph node status, lesion distribution, and molecular phenotypes remained significant.

CONCLUSIONS:

Multifocality and diffuse distribution of the invasive component were associated with significantly poorer survival in women with breast carcinomas compared with unifocal disease in patients with luminal A, HER2 type, and basal‐like cancers. Molecular classification of breast cancer is a powerful tool but gains in power when combined with conventional and subgross morphologic parameters. Cancer 2013. © 2013 American Cancer Society.
Radiation therapy target volume reduction in pediatric rhabdomyosarcoma
Authors: Eaton Bree R. , McDonald Mark W. , Kim Sungjin , Marcus Robert B. , Sutter Anna L. , Chen Zhengjia , Esiashvili Natia
Published: December 2012

BACKGROUND:

The use of radiation therapy (RT) “cone‐down” boost to reduce high‐dose treatment volumes according to tumor response to induction chemotherapy in patients with pediatric rhabdomyosarcoma (RMS) may reduce treatment morbidity, yet the impact on tumor control is unknown.

METHODS:

Fifty‐five children, including 18 (33%) with parameningeal (PM) RMS and 37 (67%) with non‐PM RMS, who received definitive treatment with chemotherapy and RT from April 2000 through January 2010 were retrospectively reviewed.

RESULTS:

In total, 28 patients (51%) received a cone‐down boost. The high‐dose boost volume was reduced by a median of 56% of the initial target volume (range, 5%‐91%). The median time to initiating RT was 3 weeks for patients with PM RMS and 16 weeks for patients with non‐PM RMS (P < .001). After a median follow‐up of 41 months, local failure occurred in 5 patients (9%), including 2 patients who received a cone‐down boost, and there were no marginal failures. Twelve patients (67%) with PM RMS had intracranial tumor extension. In this subgroup, 4 patients (30%) who received a cone‐down boost and had ≥ 3 weeks between chemotherapy and RT initiation experienced leptomeningeal failure as their first site of disease progression, and a delayed time to RT initiation was associated with decreased survival (P = .055)

CONCLUSIONS:

A cone‐down boost allowed for significant reductions in high‐dose RT treatment volume while maintaining excellent tumor control in most patients. However, in the subset of patients with PM RMS and intracranial tumor extension, early RT initiation and wider margin RT to cover adjacent areas at high risk for meningeal extension may be more important for adequate disease control. Cancer 2013. © 2012 American Cancer Society.
Density Functional Theory and Optimal Transportation with Coulomb Cost
Authors: Cotar Codina , Friesecke Gero , Klüppelberg Claudia
Published: December 2012

We present here novel insight into exchange‐correlation functionals in density functional theory, based on the viewpoint of optimal transport. We show that in the case of two electrons and in the semiclassical limit, the exact exchange‐correlation functional reduces to a very interesting functional that depends on an optimal transport map T associated with a given density ρ. The limit problem has been suggested, on grounds of formal arguments, in the physics literature, but it appears that it has not hitherto been interpreted as an optimal transport problem. Since the above limit is strongly correlated, the limit functional yields insight into electron correlations. We prove the existence and uniqueness of such an optimal map for any number of electrons and each ρ and determine the map explicitly in the case when ρ is radially symmetric. © 2012 Wiley Periodicals, Inc.