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Background: Aspergillus niger is well-known for its high protein secretion capacity and therefore an important cell factory for homologous and heterologous protein production. The use of a strong promoter and multiple gene copies are commonly used strategies to increase the gene expression and protein production of the gene of interest (GOI). We recently presented a two-step CRISPR/Cas9-mediated approach in which glucoamylase (glaA) landing sites (GLSs) are introduced at predetermined sites in the genome (step 1), which are subsequently filled with copies of the GOI (step 2) to achieve high expression of the GOI., Results: Here we show that in a ku70 defective A. niger strain (Δku70), thereby excluding non-homologous end joining (NHEJ) as a mechanism to repair double-stranded DNA breaks (DSBs), the chromosomal glaA locus or homologous GLSs can be used to repair Cas9-induced DSBs, thereby competing with the integration of the donor DNA containing the GOI. In the absence of exogenously added donor DNA, the DSBs are repaired with homologous chromosomal DNA located on other chromosomes (inter-chromosomal repair) or, with higher efficiency, by a homologous DNA fragment located on the same chromosome (intra-chromosomal repair). Single copy inter-chromosomal homology-based DNA repair was found to occur in 13-20% of the transformants while 80-87% of the transformants were repaired by exogenously added donor DNA. The efficiency of chromosomal repair was dependent on the copy number of the potential donor DNA sequences in the genome. The presence of five homologous DNA sequences, resulted in an increased number (35-61%) of the transformants repaired by chromosomal DNA. The efficiency of intra-chromosomal homology based DSB repair in the absence of donor DNA was found to be highly preferred (85-90%) over inter-chromosomal repair. Intra-chromosomal repair was also found to be the preferred way of DNA repair in the presence of donor DNA and was found to be locus-dependent., Conclusion: The awareness that homologous chromosomal DNA repair can compete with donor DNA to repair DSB and thereby affecting the efficiency of multicopy strain construction using CRISPR/Cas9-mediated genome editing is an important consideration to take into account in industrial strain design., (© 2024. The Author(s).)

Background: Compared with conventional unimodal analysis, understanding how brain function and structure relate to one another opens a new biologically relevant assessment of neural mechanisms. However, how function-structure dependencies (FSDs) evolve throughout typical and abnormal neurodevelopment remains elusive. The 22q11.2 deletion syndrome (22q11.2DS) offers an important opportunity to study the development of FSDs and their specific association with the pathophysiology of psychosis., Methods: Previously, we used graph signal processing to combine brain activity and structural connectivity measures in adults, quantifying FSD. Here, we combined FSD with longitudinal multivariate partial least squares correlation to evaluate FSD alterations across groups and among patients with and without mild to moderate positive psychotic symptoms. We assessed 391 longitudinally repeated resting-state functional and diffusion-weighted magnetic resonance images from 194 healthy control participants and 197 deletion carriers (ages 7-34 years, data collected over a span of 12 years)., Results: Compared with control participants, patients with 22q11.2DS showed a persistent developmental offset from childhood, with regions of hyper- and hypocoupling across the brain. Additionally, a second deviating developmental pattern showed an exacerbation during adolescence, presenting hypocoupling in the frontal and cingulate cortices and hypercoupling in temporal regions for patients with 22q11.2DS. Interestingly, the observed aggravation during adolescence was strongly driven by the group with positive psychotic symptoms., Conclusions: These results confirm a central role of altered FSD maturation in the emergence of psychotic symptoms in 22q11.2DS during adolescence. The FSD deviations precede the onset of psychotic episodes and thus offer a potential early indication for behavioral interventions in individuals at risk., (Copyright © 2024 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Quantum cascade lasers (QCLs) have emerged as promising candidates for generating chip-scale frequency combs in mid-infrared and terahertz wavelengths. In this work, we demonstrate frequency comb formation in ring terahertz QCLs using the injection of light from a distributed feedback (DFB) laser. The DFB design frequency is chosen to match the modes of the ring cavity (near 3.3 THz), and light from the DFB is injected into the ring QCL via a bus waveguide. By controlling the power and frequency of the optical injection, we show that combs can be selectively formed and controlled in the ring cavity. Numerical modeling suggests that this comb is primarily frequency-modulated in character, with the injection serving to trigger comb formation. We also show that the ring can be used as a filter to control the output of the DFB QCL, potentially being of interest in terahertz photonic integrated circuits. Our work demonstrates that waveguide couplers are a compelling approach for injecting and extracting radiation from ring terahertz combs and offer exciting possibilities for the generation of new comb states in terahertz, such as frequency-modulated waves, solitons, and more. [ABSTRACT FROM AUTHOR]

We study bin-packing and lot-sizing decisions in an integrated way. Such a problem appears in several manufacturing settings where items first need to be cut and next assembled into final products. One of the main novelties of this research is the modeling of the complex setup operations in the cutting process, which is modeled using a bin-packing formulation. More specifically, we consider the operation regarding the insertion or removal of the knives in the cutting process. Since this operation depends on the number of items cut in the current cutting process and in the previous one, the number of insertions and removals is sequence-dependent. The setups in the lot-sizing problem related to the production of the final products are also sequence-dependent. To deal with such a problem, two compact formulations are proposed. The sequence-dependent setups in the bin-packing problem are modeled in two different ways: based on known constraints from the literature, and based on the idea of micro-periods and a phantom cutting process. Due to the dependency in the setups decisions, the resulting formulations are mixed-integer nonlinear mathematical models. In order to deal with the sequence-dependent cutting and production setups, different polynomial-sized sets of subtour elimination constraints are employed to the coupled problem. A computational study is conducted in order to analyze the impact of the proposed approaches to model sequence-dependent setups, as well as the different subtour elimination strategies to solve the coupled bin-packing and lot-sizing problem, via an automatic-Benders decomposition algorithm. [ABSTRACT FROM AUTHOR]

THz quantum cascade lasers (QCLs) based on double metal waveguides feature broadband and high-temperature devices for their use in spectroscopy and sensing. However, their extreme field confinement produces poor output coupling efficiencies and divergent far-fields. Here, we present a planarized THz QCL with an inverse-designed end facet reflector coupled to a surface-emitting patch array antenna. All the components have been optimized for octave-spanning spectral bandwidths between 2 and 4 THz and monolithically integrated on the same photonic chip. We demonstrate this experimentally on broadband THz QCL frequency combs, with measured devices showing a seven-fold improvement in slope efficiency compared to devices with a cleaved facet. They feature a peak power of up to 13.5 mW with surface emission into a narrow beam with a divergence of (17.0° × 18.5°), while broadband fundamental and harmonic comb states spanning up to 800 GHz are observed. [ABSTRACT FROM AUTHOR]

Photonic integrated circuits have benefited many fields in the natural sciences. Their nanoscale patterning has led to the discovery of novel sources and detectors from ultraviolet to microwaves. Yet terahertz technologies have so far leveraged surprisingly little of the design and material freedom provided by photonic integrated circuits. Despite photoconduction—the process in which light is absorbed above the bandgap of a semiconductor to generate free carriers—and nonlinear up- and down-conversion being by far the two most widespread approaches to generate and detect terahertz waves, so far, terahertz technologies have been mostly employed in bulk. In this perspective, we discuss the current state-of-the-art, challenges, and perspectives for hybrid optical-terahertz photonic chips. We focus, in particular, on χ(2) and χ(3) nonlinear waveguides and waveguide-integrated photoconductive devices. We highlight opportunities in the micro- and macroscale design of waveguide geometries and printed antennas for the optimization of emission and detection efficiencies of terahertz waves. Realizing complex functionalities for terahertz photonics on a single chip may come into reach by integration and miniaturization compatible with telecom and fiber technologies. [ABSTRACT FROM AUTHOR]

In this paper, we study the label printing problem (LPP) which has applications in the printing industry. In LPP, the demand for a set of labels is satisfied by printing the labels using templates with multiple slots. Given a fixed number of templates, the decisions in LPP are determining (i) the assignment of labels to the slots of the templates (which we call template designs), and (ii) the number of prints made using each template design. The objective is to satisfy the demand with minimum waste. We consider two variants of LPP where (i) each label can be assigned to the slot(s) of a single template, and (ii) each label can be assigned to the slot(s) of multiple templates. To address LPP, we propose a novel sampling-based construct-improve heuristic where we first generate "good" template designs and then choose the ones to be used and determine the number of prints made through a set covering-type mathematical model. Then, we improve the solution using some improvement ideas that utilize a strengthened linear integer model for the problem. Using the instances from the literature, we show that the proposed heuristic provides better results compared to the benchmark algorithm. We also find optimal solutions for some of the instances from the literature using the strengthened linear integer model. With the help of the optimal solutions found we identify some problems in the previously reported results in a related study. Finally, we observe that the proposed heuristic approach not only provides better solutions but also runs in less amount of time compared to the benchmark algorithm on the large instances. [ABSTRACT FROM AUTHOR]

Controlling the growth of thin phthalocyanine films is a long-term challenge for the science of applied nanomaterials. So, this contribution deals with films of unsubstituted zinc phthalocyanine (ZnPc) and seeks to acquire structural information that is unavailable via physical experiments, thus, finding out how the film morphology can be seriously improved. A model of the vapor-deposited film has been created using the molecular dynamics method. Specifically, the ZnPc molecules are dosed into the simulation box under normal conditions, reproducing key features of the real film, such as the trimolecular wetting layer and the island-like three-dimensional (3D) phase that is structured like the α-polymorph; then all film fragments are characterized via their radial distribution functions and mean-squared displacements. The simulation model indicates that the 3D phase starts to develop smoothly through multimolecular cofacial stacking but finally becomes fragmental because the wetting layer is too meager to be a good platform for regular film growth. Accordingly, the film morphology may be improved if the wetting layer is thickened via restraining the vertical development of the 3D phase. Following this idea, uniform ZnPc films impaired by neither grain boundaries nor coarser defects were deposited from solutions and visualized at the nanometer scale. [ABSTRACT FROM AUTHOR]

A real-world planning problem of a printing company is presented where different sorts of a consumer goods' label are printed on a roll of paper with sufficient length. The printer utilizes a printing plate to always print several labels of same size and shape (but possibly different imprint) in parallel on adjacent lanes of the paper. It can be decided which sort is printed on which (lane of a) plate and how long the printer runs using a single plate. A sort can be assigned to several lanes of the same plate, but not to several plates. Designing a plate and installing it on the printer incurs fixed setup costs. If more labels are produced than actually needed, each surplus label is assumed to be "scrap". Since demand for the different sorts may be heterogeneous and since the number of sorts is usually much higher than the number of lanes, the problem is to build "printing blocks", i.e., to decide how many and which plates to design and how long to run the printer with a certain plate so that customer demand is satisfied with minimum costs for setups and scrap. This industrial application is modeled as an extension of a so-called job splitting problem which is solved exactly and by various decomposition heuristics, partly basing on dynamic programming. Numerical tests compare both approaches with further straightforward heuristics and demonstrate the benefits of decomposition and dynamic programming for large problem instances. [ABSTRACT FROM AUTHOR]

mRNA display is a powerful biological display platform for the directed evolution of proteins and peptides. mRNA display libraries covalently link the displayed peptide or protein (phenotype) with the encoding genetic information (genotype) through the biochemical activity of the small molecule puromycin. Selection for peptide/protein function is followed by amplification of the linked genetic material and generation of a library enriched in functional sequences. Iterative selection cycles are then performed until the desired level of function is achieved, at which time the identity of candidate peptides can be obtained by sequencing the genetic material. The purpose of this review is to discuss the development of mRNA display technology since its inception in 1997 and to comprehensively review its use in the selection of novel peptides and proteins. We begin with an overview of the biochemical mechanism of mRNA display and its variants with a particular focus on its advantages and disadvantages relative to other biological display technologies. We then discuss the importance of scaffold choice in mRNA display selections and review the results of selection experiments with biological (e.g., fibronectin) and linear peptide library architectures. We then explore recent progress in the development of "drug-like" peptides by mRNA display through the post-translational covalent macrocyclization and incorporation of non-proteogenic functionalities. We conclude with an examination of enabling technologies that increase the speed of selection experiments, enhance the information obtained in post-selection sequence analysis, and facilitate high-throughput characterization of lead compounds. We hope to provide the reader with a comprehensive view of current state and future trajectory of mRNA display and its broad utility as a peptide and protein design tool. [ABSTRACT FROM AUTHOR]

We describe multimodal imaging probes for gastrin‐releasing peptide receptor (GRPR)‐specific targeting suited for positron emission tomography and optical imaging (PET/OI), consisting of PESIN (PEG3‐BBN7‐14) dimers connected to multimodal imaging subunits. These multimodal agents comprise a fluorescent dye for OI and the chelator ((1,4,7‐triazacyclononane‐4,7‐diyl)diacetic acid‐1‐glutaric acid) (NODA‐GA) for PET radiometal isotope labelling. Special focus was put on the influence of the used dyes on the properties of the whole bioconjugates. For this, several compounds with different fluorescent dyes and non‐dye carrying subunits were synthesized and investigated. As fluorescent dyes, dansyl, NBD, derivatives of fluorescein, coumarin and rhodamine as well as three pyrilium‐based dyes were employed. Considerable influence of the charge of the colored unit on hydrophilicity as well as in vitro target receptor binding was observed and classified. High radiochemical yields and purities were found during radiolabeling of the multimodal imaging subunits as well as their GRPR‐specific bioconjugates with 68Ga. Examinations of the photophysical properties of both molecule species displayed no loss or alteration of fluorescence characteristics. [ABSTRACT FROM AUTHOR]

Coordination materials based on multitopic carboxylate and/or nitrogen‐containing ligands have been one of the major research interests in chemistry academia, while the ones constructed of ligands containing combined oxygen, nitrogen and sulfur donors have been relatively neglected. The present review overviews the recent progress in synthesis, structures, properties and/or applications of coordination polymers and clusters based on a group of mercaptonicotinate ligands with mixed and versatile donors. The initial discussion focuses on the in situ ligand reactions for the construction of coordination polymers, which are classified into six categories. Also, comments on the topologies of some selected coordination polymers with intriguing architectures are given. Furthermore, the properties and/or applications of the reported coordination polymers and clusters, such as luminescence, gas adsorption, magnetism, biology, and medicine are addressed in detail. The last section summarizes the achievements and outlook for future research in this realm. [ABSTRACT FROM AUTHOR]

Three-pulse radio-frequency (rf) driven electron spin echo envelope modulation (ESEEM) is introduced as a method to measure hyperfine couplings of electron–nuclear spin systems in liquids. It is distinguished from the corresponding two-pulse experiment by narrower lines. Numerical simulations of rf-driven ESEEM based on Floquet theory are given and compared with average Hamiltonian theory. Artifacts which appear in rf-driven ESEEM spectra are discussed, and approaches for the removal of these artifacts such as time-proportional phase incrementation (TPPI) of the rf phase and an rf phase cycle (0, π) are presented. The validity of the analytical description of the rf-driven ESEEM experiment is shown by comparison with experimental results. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

It is demonstrated by theory and experiment that time-domain broadband electron nuclear double resonance (ENDOR) spectroscopy can be performed by using radio frequency chirp pulses. The chirp ENDOR experiment is shown to have a sensitivity comparable to that of established pulsed ENDOR experiments while featuring at the same time a higher resolution. Two pulsed schemes are proposed for chirp ENDOR that are related to the Davies- and Mims-ENDOR experiments. A simple two-step phase cycle can remove the contributions from unwanted coherence transfer pathways and, unlike in time-domain ENDOR with pulses of fixed radio frequency, no quadrature readout is needed. The basic chirp ENDOR experiment can easily be extended by applying concepts from electron spin echo envelope modulation and nuclear magnetic resonance spectroscopy. A novel hyperfine sublevel correlation (HYSCORE) experiment based on chirp ENDOR is proposed. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most malignant form of brain tumors with dismal prognosis despite treatment by surgery combined with radiotherapy and chemotherapy. The neuropeptide Substance P (SP) is the physiological ligand of the neurokinin‐1 receptor, which is highly expressed in glioblastoma cells. Thus, SP represents a potential ligand for targeted alpha therapy. In this study, a protocol for the synthesis of SP labeled with the alpha emitter 225Ac was developed and binding affinity properties were determined. The effects of 225Ac‐DOTA‐SP were investigated on human glioblastoma cell lines (T98G, U87MG, U138MG) as well as GBM stem cells. A significant dose‐dependent reduction in cell viability was detected up to 6 days after treatment. Also, colony‐forming capacity was inhibited at the lower doses tested. In comparison, treatment with the conventional agent temozolomide showed higher cell viability and colony‐forming capacity. 225Ac‐DOTA‐SP treatment caused induction of late apoptosis pathways. Cells were arrested to G2/M‐phase upon treatment. Increasing doses and treatment time caused additional S‐phase arrest. Similar results were obtained using human glioblastoma stem cells, known to show radioresistance. Our data suggest that 225Ac‐DOTA‐SP is a promising compound for treatment of GBM. [ABSTRACT FROM AUTHOR]

Peptide sciences developed dramatically as a result of routine use of solid-phase peptide synthesis and nowadays offer a rich set of well-established strategies to design and identify functional peptide sequences for advanced applications in materials sciences. Appropriate sequences for a wide range of interesting material targets, ranging from molecules to materials surfaces and internal interfaces, can be selected via combinatorial means, and sequence specificities within the resulting peptide-target interactions can be routinely investigated. Based on this understanding, macromolecular sciences can define new polymer structures that meet required functionalities or functional sequences with fully synthetic, nonpeptidic precision polymers to endeavor toward information-based design of next-generation, purpose-adapted macromolecules. [ABSTRACT FROM AUTHOR]

We have considered the system investigated by Steinmann et al. by means of the image charge model originally proposed in Iori and Corni, J. Comput. Chem. 2008, 29, 1656. Qualitatively correct results are obtained, that compare favorably with the relevant analytical benchmarks. We show that the effect of the asymmetry of the rod model can be controlled, when needed, as originally suggested, that is, by shorter rods. This strategy does not increase neither the complexity of the model nor its computational cost. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

This review provides an overview of recent developments in “chemical virology.” Viruses, as materials, provide unique nanoscale scaffolds that have relevance in chemical biology and nanotechnology, with diverse areas of applications. Some fundamental advantages of viruses, compared to synthetically programmed materials, include the highly precise spatial arrangement of their subunits into a diverse array of shapes and sizes and many available avenues for easy and reproducible modification. Here, we will first survey the broad distribution of viruses and various methods for producing virus-based nanoparticles, as well as engineering principles used to impart new functionalities. We will then examine the broad range of applications and implications of virus-based materials, focusing on the medical, biotechnology, and energy sectors. We anticipate that this field will continue to evolve and grow, with exciting new possibilities stemming from advancements in the rational design of virus-based nanomaterials. [ABSTRACT FROM AUTHOR]

Covering: up to the end of 2015. Peptides are naturally occurring compounds that play an important role in all living systems and are responsible for a range of essential functions. Peptide receptors have been implicated in disease states such as oncology, metabolic disorders and cardiovascular disease. Therefore, natural peptides have been exploited as diagnostic and therapeutic agents due to the unique target specificity for their endogenous receptors. This review discusses a variety of natural peptides highlighting their discovery, endogenous receptors, as well as their derivatization to create molecular imaging agents, with an emphasis on the design of radiolabelled peptides. This review also highlights methods for discovering new and novel peptides when knowledge of specific targets and endogenous ligands are not available. [ABSTRACT FROM AUTHOR]

We explore a photochemical approach to achieve an ordered polymeric structure at the sub-monolayer level on a metal substrate. In particular, a tetraphenylporphyrin derivative carrying para-amino-phenyl functional groups is used to obtain extended and highly ordered molecular wires on Ag(110). Scanning tunneling microscopy and density functional theory calculations reveal that porphyrin building blocks are joined through azo bridges, mainly as cis isomers. The observed highly stereoselective growth is the result of adsorbate/surface interactions, as indicated by X-ray photoelectron spectroscopy. At variance with previous studies, we tailor the formation of long-range ordered structures by the separate control of the surface molecular diffusion through sample heating, and of the reaction initiation through light absorption. This previously unreported approach shows that the photo-induced covalent stabilization of self-assembled molecular monolayers to obtain highly ordered surface covalent organic frameworks is viable by a careful choice of the precursors and reaction conditions. [ABSTRACT FROM AUTHOR]

A density functional theory study of a cobalt(ii) octaethylporphyrin (CoOEP) monolayer on Au(111) and HOPG(0001) surfaces was performed under periodic boundary conditions. Calculations with and without dispersion corrections are performed and the effect of van der Waals forces on the interface properties is analyzed. Calculations have determined that the CoOEP molecule tends to bind at the 3-fold and the 6-fold center sites on Au(111) and HOPG(0001), respectively. Geometric optimizations at the center binding sites have indicated that the porphyrin molecules (in the monolayer) lie flat on both substrates. Calculations also reveal that the CoOEP monolayer binds slightly more strongly to Au(111) than to HOPG(0001). Charge density difference plots disclose that charge is redistributed mostly around the porphyrin plane and the first layer of the substrates. Dispersion interactions cause a larger substrate to molecule charge pushback on Au(111) than on HOPG. CoOEP adsorption tends to lower the work functions of either substrate, qualitatively agreeing with the experimental photoelectron spectroscopic data. Comparison of the density of states (DOS) of the isolated CoOEP molecule with that on gold and HOPG substrates showed significant band shifts around the Fermi energy due to intermolecular orbital hybridization. Simulated STM images were plotted with the Tersoff–Hamann approach using the local density of states, which also agree with the experimental results. This study elucidates the role of dispersion for better describing porphyrin–substrate interactions. A DFT based overview of geometric, adsorption and electronic properties of a porphyrin monolayer on conductive surfaces is presented. [ABSTRACT FROM AUTHOR]

The replacement of amide bonds in the backbone of peptides by proteolytically stable 1,2,3-triazole isosteres can provide novel peptidomimetics with promising properties for the development of tumor-targeting radiopeptides. On the basis of our previous work with radiolabeled agonistic bombesin (BBN) derivatives of the sequence [Nle14]BBN(7-14), we substituted selected amide bonds of the structurally closely related antagonistic peptide analog JMV594. With the exception of the C-terminal modification, amide-to-triazole substitutions tolerated by [Nle14]BBN(7-14) without loss of biological function led to abolished receptor affinity in the case of JMV594. These findings provide an additional piece of evidence for the currently disputed differences in the modes of action of agonistic and antagonistic gastrin-releasing peptide receptor (GRPR)-targeting radiopeptides. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel 3D bismuth–organic framework with helical channels, {[Bi(mna)2]−·(HDMA)+}n (1, H2mna = 2-mercaptonicotinic acid, DMA = dimethylamine) based on homo-chiral Bi–mna helices was hydrothermally synthesized and characterized. The optical diffuse reflectance spectrum and the theoretical calculations indicate that compound 1 is a potentially semiconductive material. [ABSTRACT FROM AUTHOR]

The formation of 2D surface-confined supramolecular porous networks is scientifically and technologically appealing, notably for hosting guest species and confinement phenomena. In this study, we report a scanning tunneling microscopy (STM) study of the self-assembly of a tripod molecule specifically equipped with pyridyl functional groups to steer a simultaneous expression of lateral pyridyl-pyridyl interactions and Cu-pyridyl coordination bonds. The assembly protocols yield a new class of porous open assemblies, the formation of which is driven by multiple interactions. The tripod forms a purely porous organic network on Ag(111), phase α, in which the presence of the pyridyl groups is crucial for porosity, as confirmed by molecular dynamics and Monte Carlo simulations. Additional deposition of Cu dramatically alters this scenario. For submonolayer coverage, three different porous phases coexist (i.e., β, γ, and δ). Phases β and γ are chiral and exhibit a simultaneous expression of lateral pyridyl-pyridyl interactions and twofold Cu-pyridyl linkages, whereas phase δ is just stabilized by twofold Cu-pyridyl bonds. An increase in the lateral molecular coverage results in a rise in molecular pressure, which leads to the formation of a new porous phase (ε), only coexisting with phase α and stabilized by a simultaneous expression of lateral pyridyl-pyridyl interactions and threefold Cu-pyridyl bonds. Our results will open new avenues to create complex porous networks on surfaces by exploiting components specifically designed for molecular recognition through multiple interactions. [ABSTRACT FROM AUTHOR]

Often referred to as the "building blocks of proteins", the 20 canonical proteinogenic amino acids are ubiquitous in biological systems as the functional units in proteins. Sometimes overlooked are their varying additional roles that include serving as metabolic intermediaries, playing structural roles in bioactive natural products, acting as cosubstrates in enzymatic transformations, and as key regulators of cellular physiology. Amino acids can also serve as biological sources of both carbon and nitrogen and are found in the rhizosphere as a result of lysis or cellular efflux from plants and microbes and proteolysis of existing peptides. While both plants and microbes apparently prefer to take up nitrogen in its inorganic form, their ability to take up and use amino acids may confer a selective advantage in certain environments where organic nitrogen is abundant. Further, certain amino acids (e.g., glutamate and proline) and their betaines (e.g., glycine betaine) serve as compatible solutes necessary for osmoregulation in plants and microbes and can undergo rapid cellular flux. This ability is of particular importance in an ecological niche such as the rhizosphere, which is prone to significant variations in solute concentrations. Amino acids are also shown to alter key phenotypes related to plant root growth and microbial colonization, symbiotic interactions, and pathogenesis in the rhizosphere. This review will focus on the sources, transport mechanisms, and potential roles of the 20 canonical proteinogenic amino acids in the rhizosphere. [ABSTRACT FROM AUTHOR]

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Doped M:ZnO nanoparticles (Zn/M = 50:1 or 20:1; M = AgI, CoII, CuII, EuIII, MgII, MnII) have been produced by an easy, reproducible, and fast inverse miniemulsion approach, enabling the co-precipitation of the nanocrystalline oxide in a confined space. Unexpectedly, the formation of crystalline materials took place at room temperature. Suspensions were characterized by dynamic light scattering and UV/Vis spectroscopy, whereas precipitated powders were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, inductively coupled plasma atomic emission spectrometry, and thermogravimetric analysis. The particles obtained showed preferential growth along the [0002] direction with a size of 70 nm, whereas along the other directions average sizes of between 26 and 33 nm were determined. The analyses confirmed successful doping in all cases but one: In fact, the Ag-doped sample is a nanocomposite consisting of metallic silver clusters dispersed in the ZnO matrix. Red emission from the ZnO:Eu sample was evidenced upon excitation at around 465 nm. [ABSTRACT FROM AUTHOR]

Two new cadmium thiolato-carboxylate complexes, [Cd(mba)(2,2′-bpy)] ( 1), [Cd(dtba)(2,2′-bpy)]·4HO ( 2) (Hmba = 2-mercaptobenzoic acid, Hdtba = 2,2′-dithiodibenzoic acid, 2,2′-bpy = 2,2′-bipyridine) were obtained by reacting Cd(II) salts and the ligands of Hmba and 2,2′-bpy, and were characterized by the single-crystal X-ray diffraction, IR, 2D-COS IR, solid UV, TG and XRD. In complex 2, the Hdtba ligand came from the in situ S-S function reaction of Hmba under the hydrothermal conditions. Complexes 1 and 2 are both 1D chains, but the difference lies in the linkage of the ligands. The 3D super-molecular frameworks of 1 and 2 are produced by π- π stacking interaction between the 2,2′-bpy ligands and the hydrogen bonds of O-H...O with ths-type and dia-type topology, respectively. The fluorescent emissions are observed in 1 and 2 with λ = 533 nm and λ = 436 nm, due to the ligand-to-metal charge transfer (LMCT) and π* → π transitions, respectively. [ABSTRACT FROM AUTHOR]

A prerequisite for starting a clinical trial is evidence of a positive impact of the technique or drug in animals. The choice of the animal model is thus very important and should mimic as closely as possible the human situation. A variety of animal models have been validated for pharmaceutical trials. The situation in phototheranostics however is not fully clear. This is due to the very complex interplay of various elements such as vascularization, oxygenation, drug availability and biodistribution, light absorption, and scattering. The present paper will give general information on aspects of animal models that have to be considered in phototheranostics, as well as highlight some typical animal models that are useful for the investigation of light-tissue interactions. [ABSTRACT FROM AUTHOR]

Fusarium is a widespread genus of filamentous fungi and a member of the soil microbial community. Certain subspecies are health threatening because of their mycotoxin production that affects the human and animal food chain. Thus, for early and effective pest control, species identification is of particular interest; however, differentiation on the subspecies level is challenging and time-consuming for this fungus. In the present study, we show the possibilities of intact cell mass spectrometry for spore analysis of 22 different Fusarium strains belonging to six Fusarium subspecies. We found that species differentiation is possible if mass spectrometric analyses are performed under well-defined conditions with fixed parameters. A critical point for analysis is a proper sample preparation of spores, which increases the quality of mass spectra with respect to signal intensity and m/z value variations. It was concluded that data acquisition has to be performed automatically; otherwise, user-specific variations are introduced generating data which cannot fit the existing datasets. Data that show clearly that matrix-assisted laser desorption ionization-based intact cell/intact spore mass spectrometry (IC/ISMS) can be applied to differentiate closely related Fusarium spp. are presented. Results show a potential to build a database on Fusarium species for accurate species identification, for fast response in the case of infections in the cornfield. We furthermore demonstrate the high precision of our approach in classification of intact Fusarium species according to the location of their collection. [ABSTRACT FROM AUTHOR]

A DOTA derivative that contains an anhydride group was readily synthesized by reacting DOTAGA with acetic anhydride and its reactivity was investigated. Opening the anhydride with propylamine led to the selective formation of one of two possible regioisomers. The structure of the obtained isomer was unambiguously determined by 1D and 2D NMR experiments, including COSY, HMBC, and NOESY techniques. This bifunctional chelating agent offers a convenient and attractive approach for labeling biomolecules and, more generally, for the synthesis of a large range of DOTA derivatives. The scope of the reaction was extended to prepare DOTA-like compounds that contained various functional groups, such as isothiocyanate, thiol, ester, and amino acid moieties. This versatile building block was also used for the synthesis of a bimodal tag for SPECT or PET/optical imaging. [ABSTRACT FROM AUTHOR]

Mycotoxins are known to affect the health of humans and husbandry animals. In contrast to wheat grains used for food and feed, whole wheat plants are rarely analysed for mycotoxins, although contaminated straw could additionally expose animals to these toxic compounds. Since the entire wheat plant may also act as source of mycotoxins emitted into the environment, an analytical method was developed, optimised and validated for the analysis of 28 different mycotoxins in above-ground material from whole wheat plants. The method comprises solid-liquid extraction and a clean-up step using a Varian Bond Elut Mycotoxin cartridge, followed by liquid chromatography with electrospray ionisation and triple quadrupole mass spectrometry. Total method recoveries for 26 out of 28 compounds were between 69 and 122% and showed limits of detection from 1 to 26 ng/g. The overall repeatability for all validated compounds was on average 7%, and their mean ion suppression 65%. Those rather high matrix effects made it necessary to use matrix-matched calibrations to quantify mycotoxins within whole wheat plants. The applicability of this method is illustrated with data from a winter wheat test field to examine the risks of environmental contamination by toxins following artificial inoculation separately with four different Fusarium species. The selected data originate from samples of a part of the field which was inoculated with Fusarium crookwellense. In the wheat samples, various trichothecenes (3-acetyl-deoxynivalenol, deoxynivalenol, diacetoxyscirpenol, fusarenone-X, nivalenol, HT-2 toxin, and T-2 toxin) as well as beauvericin and zearalenone were identified with concentrations ranging from 32 ng/g to 12 × 10 ng/g. [ABSTRACT FROM AUTHOR]

With 2 tables Abstract Ear rots caused by different Fusarium spp. are one of the most dangerous food and feed safety challenges in maize production. At present, the majority of the inbreds and hybrids are susceptible. Gibberella and Fusarium ear rots (caused by Fusarium graminearum and Fusarium verticillioides, respectively) are the two main diseases, but more than 10 further Fusarium spp. cause ear rots. Natural infection is initiated by a mixture of the local Fusarium spp., but usually one species predominates. Many maize breeders rely on natural infection to create sufficient levels of disease severity for selection-resistant genotypes; however, there are few locations where the natural infection is sufficiently uniform to make this selection efficient and successful. Thus, an artificial inoculation method normally performed with one fungal species is now used by more breeders. Most published papers on breeding for ear rot resistance are focused on either F. graminearum or F. verticillioides, and reports involving both or more Fusarium spp. are rare. Several reports support the hypothesis that resistance to multiple species especially F. graminearum, F. culmorum and F. verticillioides may be common. Significant differences in genotypic resistance after inoculation exist. Resistance to the two major modes of fungal entry into the ear, via the silk or through kernel wounds, is not correlated in all genotypes. The reason is not clear. When silk channel resistance was assessed, the data from natural and artificial inoculation trials correlated well. Analogous data relating to kernel resistance have not been published. Both native and exotic sources of resistance are important, but surprisingly little information is available. Few papers report on the use of artificial inoculation during inbred development. Most of the publications on inoculation are concerned with testing at later stages when combining ability is tested. Inbreds differ in general and specific combining ability for ear rot resistance. The expression of resistance to disease severity and resistance to toxins is often used as synonyms, but in fact they are not. Higher resistance to visual disease severities mostly results in lower toxin contamination, and the resistance level seems to be the most important factor regulating the toxin content. The mode of inheritance of resistance appears to differ: additive, possibly non-additive effects, digenic (dominant) and polygenic patterns have been identified. Improved phenotyping methods that take into account the influence of stalk rot and the use of several independent isolates are available. The QTLs mostly exhibit small effects and some are validated; however, marker-assisted selection in breeding cannot yet be foreseen. As the severity of natural infections tends to correlate with the artificial inoculation results, the incorporation of artificial inoculation methods in breeding programmes is now the most important task. As genotypic resistance differences between hybrids are high, the registration of hybrids should consider the use of the inoculation tests to choose most resistant hybrids for commercial production. This is the most rapid way to increase feed safety. [ABSTRACT FROM AUTHOR]

To date, generation of single-chain fragment variable (scFv) has become an established technique used to produce a completely functional antigen-binding fragment in bacterial systems. The advances in antibody engineering have now facilitated a more efficient and generally applicable method to produce Fv fragments. Basically, scFv antibodies produced from phage display can be genetically fused to the marker proteins, such as fluorescent proteins or alkaline phosphatase. These bifunctional proteins having both antigen-binding capacity and marker activity can be obtained from transformed bacteria and used for one-step immunodetection of biological agents. Alternatively, antibody fragments could also be applied in the construction of immunotoxins, therapeutic gene delivery, and anticancer intrabodies for therapeutic purposes. This paper provides an overview of the current studies on the principle, generation, and application of scFv. The potential of scFv in breast cancer research is also discussed in this paper. [ABSTRACT FROM AUTHOR]

In the present contribution, a series of four metal dithiocarbamates, namely 1-pyrrolidinecarbodithioate methyl ester (PyDTM) of Pd(II) and Pt(II), PtCl2(PyDTM), PtBr2(PyDTM), PdBr2(PyDTM), PdCl2(PyDTM), were analysed by x-ray Photoelectron Spectroscopy (XPS). Besides the wide scan spectra, detailed spectra for the C 1s, O 1s, N 1s, S 2s, S 2p, Pt 4f (for Pt-based compounds), Pd 3d (for Pd-based compounds), Cl 2p (for Cl containing compounds), Br 3p (for Br containing compounds) regions were acquired and the related data are presented and discussed. [ABSTRACT FROM AUTHOR]

This review traces the development and study of the second-generation photosensitizer 5,10,15,20-tetra( m-hydroxyphenyl)chlorin through to its acceptance and clinical use in modern photodynamic (cancer) therapy. The literature has been covered up to early 2011. [ABSTRACT FROM AUTHOR]