The scientific community and decision-makers are increasingly concerned about transparency reproducibility of epidemiologic studies using longitudinal healthcare databases. We explored the extent to which published pharmacoepidemiologic commercially available databases could be reproduced by other investigators. identified a nonsystematic sample 38 descriptive or comparative safety/effectiveness cohort studies. Seven were excluded from reproduction, five because violation fundamental design...

We report a high-spatial resolution imaging technique to measure optical absorption and detect chemical physical changes on surfaces embedded in thick tissue. Developing sensors concentrations implanted through tissue is an important challenge for analytical chemistry biomedical imaging. Tissue scattering dramatically reduces the of In contrast, X-rays provide high spatial but do not concentrations. describe hybrid which uses scanning X-ray beam irradiate Gd2O2S scintillators resulting...

The post-translational modifications sulfation and phosphorylation pose special challenges to mass spectral analysis due their isobaric nature lability in the gas phase, as both types of peptides dissociate through similar channels upon collisional activation. Here, we present resonant infrared photodissociation based on diagnostic sulfate phosphate OH stretches, a means differentiate sulfated from phosphorylated within framework spectrometry platform. approach is demonstrated for number...

Instruction and guidance in soft skills, such as writing speaking, are important for successful training of the future chemical workforce. Relatedly, accessible knowledge transfer on "hidden curriculum" is critical student success─this especially first generation college students, international others who may be less likely to gain this information through informal means. Included details how craft cover letters, statements, other application materials tailored specific job or award...

In contrast to the reported CCC-NHC pincer ligands that contain normal N-heterocyclic carbenes (NHC), herein we report an imidazole-based abnormal NHC (aNHC) ligand, CCC-aNHC. The CCC-aNHC Pt complex with two aNHC donors was synthesized via in situ metalation and transmetalation methodology. 1,3-phenylene(bis-2-phenyl-3-butyl imidazolium) diiodide salt reacted Zr(NMe2)4 generate a zirconium situ. It transmetalated using [Pt(COD)Cl2]. Electrospray ionization of [(BuCa-iCa-iCBu)PtI]...

While mass spectrometry remains a gold-standard tool for analyte detection, characterization, and quantitation, isomer differentiation is often challenge. Tandem common approach to increase the selectivity of energy-resolved measurements can provide further improvements. However, not all spectrometers, especially those that are very compact affordable, amenable such experiments. For instance, single-stage spectrometers with soft ionization no dissociation information quadrupole ion trap...

The development of chronic liver diseases is mediated by sustained hepatic inflammation. Our objective was to characterize the molecular mechanisms responsible for inflammatory response time-limited TNF-α and IL-1β expression. C57Bl/6 mice were injected with 2 × 10 7 plaque forming units intraperitoneally an adenoviral vector containing or (AdTNF-α AdIL-1β). A nonreplicating served as control. Four days later, under ketamine xylazine anesthesia, microvasculature examined intravital...

Ionic liquids are used for myriad applications, including as catalysts, solvents, and propellants. Specifically, 2-hydroxyethylhydrazinium nitrate (HEHN) has been developed a chemical propellant space applications. The gas-phase behavior of HEHN ions clusters is important in understanding its potential an electrospray thruster propellant. Here, the unimolecular dissociation pathways two experimentally observed, theoretical modeling hydrogen bonding to help rationalize those observations....

Infrared multiple photon dissociation (IRMPD) spectroscopy is a powerful tool used to probe the vibrational modes-and, by extension, structure-of an ion within trap mass spectrometer. Compared traditional FTIR spectroscopy, IRMPD has advantages including its sensitivity and relative ability handle complex mixtures. While historically been technique for fundamental analyses, it increasingly being applied in more analytical fashion. Notable recent demonstrations pertinent clinical laboratory...

We present an infrared laser-based mass spectrometric strategy to differentiate peptides that are phosphorylated (i.e., containing pS, pT, or pY) from those nonphosphorylated S, T, Y), and have none of these moieties neither pY nor Y). This is demonstrated for a series tripeptides two larger octapeptides, showing the diagnostic phosphate OH stretch (indicative can be distinguished alcohol In addition, multiple photon dissociation (IRMPD) spectra peptide analytes recorded simultaneously in...

Sepsis, a global health issue, is the most common cause of mortality in intensive care unit. The aim this study was to develop new model sepsis that investigates impact prolonged western diet (WD) induced obesity on response early sepsis. Male C57BL/6 mice were fed either high fat WD or normal chow (NCD) for 6, 15, 27 weeks. Septic obese at 15 and weeks had significantly lower levels lung myeloperoxidase (26.3 ± 3.80 U/mg tissue) compared age matched ad lib (44.1 2.86 restricted (63.2 5.60...

Ionic liquids are now used in applications ranging from chemical synthesis to spacecraft propulsion. With this comes the need characterize new syntheses, identify environmental contamination, and determine eventual fate terrestrial space environments. This work investigates effects of source conditions, particularly capillary temperature, on observed mass spectrum determines collision-induced dissociation (CID) patterns imidazolium-based ionic liquid cations as a function their substituent...

Electrospray thrusters using ionic liquid (IL)-based propellants are quickly gaining popularity in spacecraft design. Mass spectrometry is especially well-suited to provide important knowledge on the fundamentals of how these systems work and evaluating their efficiencies impacts, given that operating principles electrospray closely mimics mass experiment - both ions generated by then enter a vacuum. Here, thruster technology IL-based briefly introduced. This introduction followed discussion...

To characterize the effect of systemically administered AGP on early leukocyte recruitment in livers endotoxemic or septic mice and to determine whether this is influenced by LPS sequestration.Endotoxemia was induced C57Bl/6 via intraperitoneal injection LPS. Sepsis cecal ligation perforation. (165 mg/kg) saline (20 mL/kg) HAS (200 immediately after surgery hepatic microcirculation examined intravital microscopy at four hour.Leukocyte adhesion PSV reduced treatment with subjected either CLP...

Mass spectrometers are ever-increasingly powerful, user-friendly, and affordable. Thus, the addition of mass spectrometry experiments into undergraduate laboratory curriculum is now both feasible an effective tool to introduce students relevant instrumentation. Here experiment demonstrating use a high-resolution electrospray ionization spectrometer (ESI-HRMS) for identification peptide sequences differentiation isomeric peptides was developed implemented in biochemistry course third-year...

Protic ionic liquids are promising candidates for many applications, including as spacecraft propellants. For both fundamental interest and understanding clustering dissociation during electrospray-based propulsion, it is useful to explore the pathways of protic liquid clusters, well factors affecting relative contributions each pathway observed MS/MS spectra. With that said, most published reports on cluster have focused aprotic liquids. The purpose current work (eg, loss amine, nitric...