A Critical View on the Use of DNA Hydrogels in Cell-Free Protein Synthesis.

Numerous studies have reported in the past that the use of protein-encoding DNA hydrogels as templates for cell-free protein synthesis (CFPS) leads to better yields than the use of conventional templates such as plasmids or PCR fragments. Systematic investigation of different types of bulk materials from pure DNA hydrogels and DNA hydrogel composites using a commercially available CFPS kit showed no evidence of improved expression efficiency. However, protein-coding DNA hydrogels were advantageously used in microfluidic reactors as immobilized templates for repetitive protein production, suggesting that DNA-based materials offer potential for future developments in high-throughput profiling or rapid in situ characterization of proteins.

Quantitative Characterization of RCA-Based DNA Hydrogels - Towards Rational Materials Design.

DNA hydrogels hold significant promise for biomedical applications and can be synthesized through enzymatic Rolling Circle Amplification (RCA). Due to the exploratory nature of this emerging field, standardized RCA protocols specifying the impact of reaction parameters are currently lacking. This study varied template sequences and reagent concentrations, evaluating RCA synthesis efficiency and hydrogel mechanical properties through quantitative PCR (qPCR) and indentation measurements, respectively.

Chiral plasmonic metasurface assembled by DNA origami.

Chiral materials are essential to perceive photonic devices that control the helicity of light. However, the chirality of natural materials is rather weak, and relatively thick films are needed for noticeable effects. To overcome this limitation, artificial photonic materials were suggested to affect the chiral response in a much more substantial manner.

Micromechanical Indentation Platform for Rapid Analysis of Viscoelastic Biomolecular Hydrogels.

The advent of biomedical applications of soft bioinspired materials has entailed an increasing demand for streamlined and expedient characterization methods meant for both research and quality control objectives. Here, a novel measurement system for the characterization of biological hydrogels with volumes as low as 75 µL was developed. The system is based on an indentation platform equipped with micrometer drive actuators that allow the determination of both the fracture points and Young's moduli of relatively stiff polymers, including agarose, as well as the measurements of viscosity for exceptionally soft and viscous hydrogels, such as DNA hydrogels.

Activity-enhanced DNAzyme for design of label-free copper(II) biosensor.

Metal ion-driven, DNA-cleaving DNAzymes are characterised by high selectivity and specificity. However, their use for metal ion sensing remains largely unexplored due to long reaction times and poor reaction yields relative to RNA-cleaving DNAzymes and other sensing strategies. Herein we present a study demonstrating a significant rate enhancement of a copper-selective DNA cleaving DNAzyme by both polydopamine (PDA) and gold (Au) nanoparticles (NPs).

CT after interhospital transfer in acute ischemic stroke: Imaging findings and impact of prior intravenous contrast administration.

Objectives: Large vessel occlusion (LVO) stroke patients routinely undergo interhospital transfer to endovascular thrombectomy capable centers. Imaging is often repeated with residual intravenous (IV) iodine contrast at post-transfer assessment. We determined imaging findings and the impact of residual contrast on secondary imaging.

Thin-Film-Based SAW Magnetic Field Sensors.

In this work, the first surface acoustic-wave-based magnetic field sensor using thin-film AlScN as piezoelectric material deposited on a silicon substrate is presented. The fabrication is based on standard semiconductor technology. The acoustically active area consists of an AlScN layer that can be excited with interdigital transducers, a smoothing SiO layer, and a magnetostrictive FeCoSiB film.

Formulation of DNA Nanocomposites: Towards Functional Materials for Protein Expression.

DNA hydrogels are an emerging class of materials that hold great promise for numerous biotechnological applications, ranging from tissue engineering to targeted drug delivery and cell-free protein synthesis (CFPS). In addition to the molecular programmability of DNA that can be used to instruct biological systems, the formulation of DNA materials, e.g.

Hippocampus subfield volumetry after microsurgical or endovascular treatment of intracranial aneurysms-an explorative study.

Background: To study hippocampus subfield volumes in patients after microsurgical clipping (MC) and/or endovascular coiling (EC) of intracranial aneurysms.

Methods: Hippocampus subfield volumetry was performed using FreeSurfer v6.0 in 51 patients (35 females, mean age 54.

Thrombus Permeability in Admission Computed Tomographic Imaging Indicates Stroke Pathogenesis Based on Thrombus Histology.

Background and Purpose- Intracranial thrombi can be characterized according to their permeability as measured by contrast agent penetration. Thrombus composition and its associated pathogenesis are important factors affecting treatment and secondary prevention. We aimed to explore the histopathologic factors explaining the heterogeneity of thrombus permeability measures and evaluated potential correlations with stroke pathogenesis.

Epidemiologic analysis of change in eyelash characteristics with increasing age in a population of healthy women.

Background: Observations that eyelashes become thinner, shorter, and lighter, as women age has not been previously quantified.

Objective: This study was conducted to investigate associations between eyelash characteristics and age.

Materials And Methods: The upper natural eyelashes of 179 subjects were photographed and analyzed (digital image analysis); length, thickness, and darkness (intensity: 0 = white and 255 = black) were calculated.

NCCN Task Force Report: Estrogen Receptor and Progesterone Receptor Testing in Breast Cancer by Immunohistochemistry.

The NCCN Task Force on Estrogen Receptor and Progesterone Receptor Testing in Breast Cancer by Immunohistochemistry was convened to critically evaluate the extent to which the presence of the estrogen receptor (ER) and progesterone receptor (PgR) biomarkers in breast cancer serve as prognostic and predictive factors in the adjuvant and metastatic settings, and the ability of immunohistochemical (IHC) detection of ER and PgR to provide an accurate assessment of the expression of these biomarkers in breast cancer tumor tissue. The task force is a multidisciplinary panel of 13 experts in breast cancer who are affiliated with NCCN member institutions and represent the disciplines of pathology, medical oncology, radiation oncology, surgical oncology, and biostatistics. The main overall conclusions of the task force are ER is a strong predictor of response to endocrine therapy; ER status of all samples of invasive breast cancer or ductal carcinoma in situ (DCIS) should be evaluated by IHC; IHC measurements of PgR, although not as important clinically as ER, can provide useful information and should also be performed on all samples of invasive breast cancer or DCIS; IHC is the main testing strategy for evaluating ER and PgR in breast cancer and priority should be given to improve the quality of IHC testing methodologies; all laboratories performing IHC assays of ER and PgR should undertake formal validation studies to show both technical and clinical validation of the assay in use; and all laboratories performing IHC assays of hormone receptors in breast cancer should follow additional quality control and assurance measures as outlined in the upcoming guidelines from the American Society of Clinical Oncology and College of American Pathologists.

NCCN Task Force Report: breast cancer in the older woman.

Breast cancer is common in older women, and the segment of the U.S. population aged 65 years and older is growing rapidly.

HER2 testing in breast cancer: NCCN Task Force report and recommendations.

The NCCN HER2 Testing in Breast Cancer Task Force was convened to critically evaluate the ability of the level of HER2 expression or gene amplification in breast cancer tumors to serve as a prognostic and a predictive factor in the metastatic and adjuvant settings, to assess the reliability of the methods of measuring HER2 expression or gene amplification in the laboratory, and to make recommendations regarding the interpretation of test results. The Task Force is a multidisciplinary panel of 24 experts in breast cancer representing the disciplines of medical oncology, pathology, radiation oncology, surgical oncology, epidemiology, and patient advocacy. Invited members included members of the NCCN Breast Cancer Panel and other needed experts selected solely by the NCCN.

Cytochrome c peroxidase complexed with cytochrome c has an unperturbed heme moiety.

Transient resonance Raman, Raman difference, circular dichroism (CD), and optical absorption studies have been carried out on the electrostatic complexes formed by yeast cytochrome c peroxidase (CCP) with horse cytochrome c (Cytc) in low ionic strength solutions. In all the complexes examined [e.g.

A comparison of spectral and physicochemical properties of yeast iso-1 cytochrome c and Cys 102-modified derivatives of the protein.

Derivatives of yeast iso-1 cytochrome c, chemically modified at Cys-102 (Cys-102 acetamide-derivatized monomer, Cys-102 thionitrobenzoate-derivatized monomer, Cys-102 S-methylated monomer, and the disulfide dimer), exhibit different spectral and physicochemical properties relative to the native, unmodified protein, depending on the nature of the modifying group. The results of proton NMR studies on the Cys-102 acetamide-derivatized monomer of iso-1 ferricytochrome c indicate that the conformational characteristics of the heme environment in this protein derivative are intermediate between those of the unmodified monomer and disulfide dimer forms of the protein. Measurements of the pKa of the alkaline transitions of the five forms of iso-1 ferricytochrome c provided values of 8.

Fluorescence studies of the location and membrane accessibility of the palmitoylation sites of rhodopsin.

Fluorescent fatty acid labels have been incorporated into the palmitoylation sites of rhodopsin and used to probe the membrane accessibility and location of these sites. The fluorescence properties of anthroyloxy and pyrenyl fatty acids bound to rhodopsin were investigated in a reconstituted vesicle system. Collisional quenching of fluorescence by stearic acid (DSA) labeled with doxyls in the 16, 12, and 5 positions was used to determine the membrane accessibility and disposition of the modifying fatty acids.

Fluorescence labeling of the palmitoylation sites of rhodopsin.

Two tandem cysteine residues in the carboxyl-terminal region of rhodopsin have been shown to be covalently linked to palmitate via thioester bonds (Ovchinnikov, Y. A., et al.

Species-specific differences in covalently crosslinked complexes of yeast cytochrome c peroxidase with horse and yeast iso-1 ferricytochromes c.

1. The results of chemically crosslinking yeast cytochrome c peroxidase with both horse and yeast iso-1 ferricytochromes c have been studied by a combination of gel electrophoresis and proton NMR spectroscopy. 2.

Proton NMR comparison of noncovalent and covalently cross-linked complexes of cytochrome c peroxidase with horse, tuna, and yeast ferricytochromes c.

Proton NMR spectroscopy at 500 and 361 MHz has been used to characterize the noncovalent or electrostatic complexes of yeast cytochrome c peroxidase (CcP) with horse, tuna, yeast isozyme-1, and yeast isozyme-2 ferricytochromes c and the covalently cross-linked complexes of cytochrome c peroxidase with horse and yeast isozyme-1 ferricytochromes c. Under the conditions employed in this work, the stoichiometry of the predominant complex formed in solution (which totaled greater than 90% of complex formed) was found to be 1:1 in all cases. These studies have elucidated significant differences in the proton NMR absorption spectra and the one-dimensional nuclear Overhauser effect difference spectra of the complexes, depending on the specific species of ferricytochrome c incorporated.

Proton-NMR studies of the effects of ionic strength and pH on the hyperfine-shifted resonances and phenylalanine-82 environment of three species of mitochondrial ferricytochrome c.

Ferricytochromes c from three species (horse, tuna, yeast) display sensitivity to variations in solution ionic strength or pH that is manifested in significant changes in the proton NMR spectra of these proteins. Irradiation of the heme 3-CH3 resonances in the proton NMR spectra of tuna, horse and yeast iso-1 ferricytochromes c is shown to give NOE connectivities to the phenyl ring protons of Phe82 as well as to the beta-CH2 protons of this residue. This method was used to probe selectively the Phe82 spin systems of the three cytochromes c under a variety of solution conditions.

One- and two-dimensional proton NMR studies of cys-102 S-methylated yeast isozyme-1 ferricytochrome c.

The effect of S-methylating cysteine-102 (cys-102) (SH----SSCH3) of yeast isozyme-1 (iso-1) ferricytochrome c has been studied using proton NMR spectroscopy. COSY, NOESY, and one-dimensional nuclear Overhauser effect (NOE) difference spectroscopies have all been used. The NMR spectrum of this derivative is very similar to that of native yeast iso-1 ferricytochrome c.

Proton NMR comparison of the Saccharomyces cerevisiae ferricytochrome c isozyme-1 monomer and covalent disulfide dimer.

Proton NMR studies of Saccharomyces cerevisiae (bakers yeast) isozyme-1 monomer and dimer ferricytochrome c have been carried out. The dimer is formed via a disulfide bridge between the Cys-102 residues of monomer proteins. Nuclear Overhauser effect (NOE) experiments have led to resonance assignments for many of the heme and axial ligand (Met-80; His-18) protons in both protein forms.

Kinetics of intracomplex electron transfer and of reduction of the components of covalent and noncovalent complexes of cytochrome c and cytochrome c peroxidase by free flavin semiquinones.

The kinetics of reduction of free flavin semiquinones of the individual components of 1:1 covalent and electrostatic complexes of yeast ferric and ferryl cytochrome c peroxidase and ferric horse cytochrome c have been studied. Covalent cross-linking between the peroxidase and cytochrome c at low ionic strength results in a complex that has kinetic properties both similar to and different from those of the electrostatic complex. Whereas the cytochrome c heme exposure to exogenous reductants is similar in both complexes, the apparent electrostatic environment near the cytochrome c heme edge is markedly different.

Assignment of hyperfine-shifted resonances in yeast ferricytochrome c isozyme 2 using the proton pre-steady-state nuclear Overhauser effect.

Yeast cytochrome c isozyme 2 is one of two cytochrome c isozymes which are found in yeast mitochondria. Unlike isozyme 1, which can dimerize in vitro due to a free sulfhydryl group at primary sequence position 102, isozyme 2 (Ala-102) is a monomer. The hyperfine proton NMR resonance pattern of ferric isozyme 2 is somewhat different from the horse and tuna ferricytochromes c.