HER2 as a potential therapeutic target on quiescent prostate cancer cells.

Quiescent prostate cancer (PCa) cells are common in tumors but are often resistant to chemotherapy. Quiescent PCa cells are also enriched for a stem-like tumor initiating population, and can lead to recurrence after dormancy. Unfortunately, quiescent PCa cells are difficult to identify and / or target with treatment in part because the relevant markers are intracellular and regulated by protein stability.

Obesity-induced follicular phase endometrial proteome dysregulation in a well-phenotyped population.

Objective: Despite obesity's significant impact on reproduction, its influence on the physiology of the human endometrium is largely understudied. We hypothesized that endometrial proteomic differences exist between obese (OW; body mass index [BMI] ≥30 kg/m) and normal-weight women (NWW; BMI, 18.5-24.

A hybridoma-derived monoclonal antibody with high homology to the aberrant myeloma light chain.

The identification of antibody variable regions in the heavy (VH) and light (VL) chains from hybridomas is necessary for the production of recombinant, sequence-defined monoclonal antibodies (mAbs) and antibody derivatives. This process has received renewed attention in light of recent reports of hybridomas having unintended specificities due to the production of non-antigen specific heavy and/or light chains for the intended antigen. Here we report a surprising finding and potential pitfall in variable domain sequencing of an anti-human CD63 hybridoma.

Assessment of the Cytoprotective Effects of High-Dose Valproic Acid Compared to a Clinically Used Lower Dose.

Objective: Valproic acid (VPA) treatment improves survival in animal models of injuries on doses higher than those allowed by Food and Drug Administration (FDA). We investigated the proteomic alterations induced by a single high-dose (140mg/kg) of VPA (VPA140) compared to the FDA-approved dose of 30mg/kg (VPA30) in healthy humans. We also describe the proteomic and transcriptomic changes induced by VPA140 in an injured patient.

Valproic acid treatment rescues injured tissues after traumatic brain injury.

Background: No agents that are specifically neuroprotective are currently approved to emergently treat patients with traumatic brain injury (TBI). The histone deacetylase inhibitor, high-dose valproic acid (VPA) has been shown to have cytoprotective potential in models of combined TBI and hemorrhagic shock, but it has not been tested in an isolated TBI model. We hypothesized that VPA, administered after isolated TBI, will penetrate the injured brain, attenuate the lesion size, and activate prosurvival pathways.

Scale-dependent particle diffusivity and apparent viscosity in polymer solutions as probed by dynamic magnetic nanorheology.

In several upcoming rheological approaches, including methods of micro- and nanorheology, the measurement geometry is of critical impact on the interpretation of the results. The relative size of the probe objects employed (as compared to the intrinsic length scales of the sample to be investigated) becomes of crucial importance, and there is increasing interest to investigate the dynamic processes and mobility in nanostructured materials. A combination of different rheological approaches based on the rotation of magnetically blocked nanoprobes is used to systematically investigate the size-dependent diffusion behavior in aqueous poly(ethylene glycol) (PEG) solutions with special attention paid to the relation of probe size to characteristic length scales within the polymer solutions.

Citrullinated Inhibitor of DNA Binding 1 Is a Novel Autoantigen in Rheumatoid Arthritis.

Objective: To explore the intrinsic role of inhibitor of DNA binding 1 (ID-1) in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) and to investigate whether ID-1 is citrullinated and autoantigenic in RA.

Methods: RA patient serum ID-1 levels were measured before and after infliximab treatment. RA FLS were transfected with a clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 construct targeting ID-1 to examine the effects of ID-1 deletion.

In-Field Orientation and Dynamics of Ferrofluids Studied by Mössbauer Spectroscopy.

By studying the response behavior of ferrofluids of 6-22 nm maghemite nanoparticles in glycerol solution exposed to external magnetic fields, we demonstrate the ability of Mössbauer spectroscopy to access a variety of particle dynamics and static magnetic particle characteristics at the same time, offering an extensive characterization of ferrofluids for in-field applications; field-dependent particle alignment and particle mobility in terms of Brownian motion have been extracted simultaneously from a series of Mössbauer spectra for single-core particles as well as for particle agglomerates. Additionally, information on Néel superspin relaxation and surface spin frustration could be directly inferred from this analysis. Parameters regarding Brownian particle dynamics, as well as Néel-type relaxation behavior, obtained via Mössbauer spectroscopy, have been verified by complementary AC-susceptometry experiments, modulating the AC-field amplitude, and using an extended frequency range of 10 to 10 Hz, while field-dependent particle alignment has been cross-checked via magnetometry.

C-terminal processing of GlyGly-CTERM containing proteins by rhombosortase in Vibrio cholerae.

Vibrio cholerae and a subset of other Gram-negative bacteria, including Acinetobacter baumannii, express proteins with a C-terminal tripartite domain called GlyGly-CTERM, which consists of a motif rich in glycines and serines, followed by a hydrophobic region and positively charged residues. Here we show that VesB, a V. cholerae serine protease, requires the GlyGly-CTERM domain, the intramembrane rhomboid-like protease rhombosortase, and the type II secretion system (T2SS) for localization at the cell surface.

Fe Deficiencies, FeO Subdomains, and Structural Defects Favor Magnetic Hyperthermia Performance of Iron Oxide Nanocubes into Intracellular Environment.

Herein, by studying a stepwise phase transformation of 23 nm FeO-FeO core-shell nanocubes into FeO, we identify a composition at which the magnetic heating performance of the nanocubes is not affected by the medium viscosity and aggregation. Structural and magnetic characterizations reveal the transformation of the FeO-FeO nanocubes from having stoichiometric phase compositions into Fe-deficient FeO phases. The resultant nanocubes contain tiny compressed and randomly distributed FeO subdomains as well as structural defects.

Rapid valproic acid-induced modulation of the traumatic proteome in a porcine model of traumatic brain injury and hemorrhagic shock.

Background: Histone deacetylase inhibitors such as valproic acid (VPA) improve survival in lethal models of hemorrhagic shock and polytrauma. Although VPA is known to modulate transcription, its ability to reduce mortality within minutes of administration suggests involvement of a rapid, posttranslational mechanism. We hypothesized that VPA treatment would cause proteomic changes within minutes of treatment including quantitative and/or posttranslational differences in structural and/or effector proteins.

Alterations in the human proteome following administration of valproic acid.

Background: High doses of the histone deacetylase inhibitor valproic acid (VPA, 150-400 mg/kg) improve outcomes in animal models of lethal insults. We are conducting a US Food and Drug Administration-approved Phase I, double-blind, placebo-controlled trial to evaluate the safety and tolerability of ascending doses of VPA in human volunteers. We hypothesized that VPA would induce significant changes in the proteome of healthy humans when given at doses lower than those used in prior animal studies.

Simultaneous Study of Brownian and Néel Relaxation Phenomena in Ferrofluids by Mössbauer Spectroscopy.

We demonstrate the ability of Mössbauer spectroscopy to simultaneously investigate Brownian motion and Néel relaxation in ferrofluidic samples. For this purpose, Mössbauer spectra of coated iron oxide nanoparticles with core diameters of 6.0-26.

Proteogenomic analysis of psoriasis reveals discordant and concordant changes in mRNA and protein abundance.

Background: Psoriasis is a chronic disease characterized by the development of scaly red skin lesions and possible co-morbid conditions. The psoriasis lesional skin transcriptome has been extensively investigated, but mRNA levels do not necessarily reflect protein abundance. The purpose of this study was therefore to compare differential expression patterns of mRNA and protein in psoriasis lesions.

Preparation of Core-Shell Hybrid Materials by Producing a Protein Corona Around Magnetic Nanoparticles.

Nanoparticles experience increasing interest for a variety of medical and pharmaceutical applications. When exposing nanomaterials, e.g.

Self-consistent magnetic properties of magnetite tracers optimized for magnetic particle imaging measured by ac susceptometry, magnetorelaxometry and magnetic particle spectroscopy.

Sensitivity and spatial resolution in Magnetic Particle Imaging are affected by magnetic properties of the nanoparticle tracers used during imaging. Here, we have carried out a comprehensive magnetic characterization of single-core iron oxide nanoparticles that were designed for MPI. We used ac susceptometry, fluxgate magnetorelaxometry, and magnetic particle spectroscopy to evaluate the tracer's magnetic core size, hydrodynamic size, and magnetic anisotropy.

1,3-dinitrobenzene induces age- and region-specific oxidation to mitochondria-related proteins in brain.

Regions of the brain with high energy requirements are especially sensitive to perturbations in mitochondrial function. Hence, neurotoxicant exposures that target mitochondria in regions of high energy demand have the potential to accelerate mitochondrial damage inherently occurring during the aging process. 1,3-Dinitrobenzene (DNB) is a model neurotoxicant that selectively targets mitochondria in brainstem nuclei innervated by the eighth cranial nerve.

Solar ultraviolet irradiation induces decorin degradation in human skin likely via neutrophil elastase.

Exposure of human skin to solar ultraviolet (UV) irradiation induces matrix metalloproteinase-1 (MMP-1) activity, which degrades type I collagen fibrils. Type I collagen is the most abundant protein in skin and constitutes the majority of skin connective tissue (dermis). Degradation of collagen fibrils impairs the structure and function of skin that characterize skin aging.

Disparate mechanisms of sICAM-1 production in the peripheral lung: contrast between alveolar epithelial cells and pulmonary microvascular endothelial cells.

Membrane-associated intercellular adhesion molecule-1 (mICAM-1; CD54) is constitutively expressed on the surface of type I alveolar epithelial cells (AEC). Soluble ICAM-1 (sICAM-1) may be produced by proteolytic cleavage of mICAM-1 or by alternative splicing of ICAM-1 mRNA. In contrast to inducible expression seen in most cell types, sICAM-1 is constitutively released by type I AEC and is present in normal alveolar lining fluid.

A new alpha-galactosyl-binding protein from the mushroom Lyophyllum decastes.

A new alpha-galactosyl binding lectin was isolated from the fruiting bodies of the mushroom Lyopyllum decastes. It is a homodimer composed of noncovalently-associated monomers of molecular mass 10,276Da. The lectin's amino acid sequence was determined by cloning from a cDNA library using partial sequences determined by automated Edman sequencing and by mass spectrometry of enzyme-derived peptides.

Backbone dynamics determined by electron paramagnetic resonance to optimize solid-phase peptide synthesis of TOAC-labeled phospholamban.

Electron paramagnetic resonance (EPR) was used to optimize the solid-phase peptide synthesis of a membrane-bound peptide labeled with TOAC (2,2,6,6-tetramethyl-piperidine-1-oxyl-4-amino-4-carboxylic acid). The incorporation of this paramagnetic amino acid results in a nitroxide spin label coupled rigidly to the alpha-carbon, providing direct detection of peptide backbone dynamics by EPR. We applied this approach to phospholamban, which regulates cardiac calcium transport.

Cyclic and hairpin peptide complexes of heme.

We have synthesized and characterized a new class of heme-peptide complexes using disulfide-linked hairpin-turn and cyclic peptides and compared these to their linear analogues. The binding affinities, helicities, and mechanism of binding of linear, hairpin, and cyclic peptides to [FeIII(coproporphyrin-I)]+ have been determined. In a minimalist approach, we utilize amphiphilic peptide sequences (15-mers), where a central histidine provides heme ligation, and the hydrophobic effect is used to optimize heme-peptide complex stability.

[Side reactions in peptide synthesis. V. O-sulfonation of serine and threonine during removal of pmc- and mtr-protecting groups from arginine residues in fmoc-solid phase synthesis].

A novel side reaction in Fmoc-solid-phase synthesis, which occurs during removal of protecting groups and detachment from the resin, was elucidated by investigations on model peptides: During the cleavage of Pmc- or Mtr-protecting groups from arginine residues by trifluoroacetic acid in peptides with O-tert-butyl-protected aliphatic hydroxyamino acids, peptides containing O3-sulfo-serine and O3-sulfo-threonine are formed as side-products in high yields, if suitable scavengers are absent. Subsequent to their isolation and purification, the structures of these peptide sulfuric acid mono-esters could unequivocally be proven by chemical and spectroscopic (MS, NMR, IR) methods.