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Potassium channels allow K+ to rapidly diffuse, while the selectivity filter (SF) actively blocks Na+. The presence of water in the SF during ion translocation remains under debate due to the experimental and computational challenges in characterizing the interactions between water, ions, and the SF. Our bottom-up approach has been applied to a system composed of a partial peptide of the SF (Ac-tyrosine-NHMe) with a metal ion and a single water molecule to probe these interactions. The IR photodissociation spectra of M+Ac-tyrosine-NHMe(H2O) (M = Na, K) combined with quantum chemical calculations revealed that the water molecule binding sites are ion-dependent. In addition, the ion–peptide distances are elongated significantly for the K+ complex in comparison to the Na+ complex by the addition of a single water molecule. This striking structural difference with the water molecule is discussed in relation to ion selectivity and translocation within the K+ channel.

Domain-specific BET bromodomain ligands represent an attractive target for drug discovery with the potential to unlock the therapeutic benefits of antagonizing these proteins without eliciting the toxicological aspects seen with pan-BET inhibitors. While we have reported several distinct classes of BD2 selective compounds, namely, GSK620, GSK549, and GSK046, only GSK046 shows high aqueous solubility. Herein, we describe the lead optimization of a further class of highly soluble compounds based upon a picolinamide chemotype. Focusing on achieving >1000-fold selectivity for BD2 over BD1 ,while retaining favorable physical chemical properties, compound 36 was identified as being 2000-fold selective for BD2 over BD1 (Brd4 data) with >1 mg/mL solubility in FaSSIF media. 36 represents a valuable new in vivo ready molecule for the exploration of the BD2 phenotype.

A number of reports have recently been published describing the discovery and optimization of bromo and extraterminal inhibitors which are selective for the second bromodomain (BD2); these include our own work toward GSK046 (3) and GSK620 (5). This paper describes our approach to mitigating the genotoxicity risk of GSK046 by replacement of the acetamide functionality with a heterocyclic ring. This was followed by a template-hopping and hybridization approach, guided by structure-based drug design, to incorporate learnings from other BD2-selective series, optimize the vector for the amide region, and explore the ZA cleft, leading to the identification of potent, selective, and bioavailable compounds 28 (GSK452), 39 (GSK737), and 36 (GSK217).

Background: Hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (Her2-) breast cancers represent the majority of metastatic breast cancers (mBC) among women and are often treated with sequential courses of endocrine therapy (ET) prior to the eventual need for chemotherapy (CT). Inhibitors of cyclin-dependent kinases 4 and 6 (CDK4/6i) block cell cycle progression and decrease proliferation of breast cancer cells. Currently, there are three available CDK4/6i: palbociclib, ribociclib and abemaciclib. Each has been shown to improve progression-free survival (PFS) when given with ET in the frontline setting, compared to ET alone. After progression on CDK4/6i, no standard of care exists for the next line of systemic therapy, and there are no prospective data to help guide clinical practice. Analysis of real-world data may provide insight into optimal second-line treatment for women who have progressed on CDK4/6i therapy. Methods: The nationwide Flatiron Health electronic health record-derived de-identified database was utilized for this analysis. We evaluated patient data collected from 2015-2020 for women with HR+/Her2- mBC who received CDK4/6i as frontline therapy and received a documented second-line systemic therapy. The objectives of this study were to describe what therapies were given as second-line treatment and estimate the real-world PFS (rwPFS) of those therapies. rwPFS was defined as time between initiation of second-line therapy until clinician-recorded progression (or death). Patients (pts) who did not progress or die were considered censored at the end of follow-up or end of second-line therapy. Results: A total of 1,210 pts with HR+/Her2- mBC received CDK4/6i with ET in the frontline setting, including 29.1% with de novo metastatic disease. Average age at diagnosis of metastatic disease was 64.4 years (range 28-84). A majority of pts received palbociclib in the frontline setting (88.2%), and 68.8% received an aromatase inhibitor (AI) as the frontline ET partner. 839 pts subsequently received second-line therapy (Table 1). CDK4/6i was continued as part of second-line treatment in 308 (36.7%) pts. 249 (29.7%) pts received CT as second-line treatment. The proportion of pts who continued CDK4/6i increased from years 2015-2020 (p=0.035), and the proportion who received CT decreased over time (p TABLE 1. Second-Line Therapy Used. F, fulvestrant; T, tamoxifenSECOND-LINE THERAPYOverall (N=839)AI23 (2.7%)CDK4/6i4 (0.5%)CDK4/6i + AI97 (11.6%)CDK4/6i + F160 (19.1%)CDK4/6i + F + AI35 (4.2%)CDK4/6i + F + T3 (0.4%)CDK4/6i + T3 (0.4%)CT249 (29.7%)F70 (8.3%)F + AI14 (1.7%)mTOR99 (11.7%)PARP4 (0.5%)PI3K16 (1.9%)T11 (1.3%)Clinical Trial51 (6.1%) Citation Format: James M Martin, Elizabeth A Handorf, Alberto J Montero, Lori J Goldstein. Analysis of systemic therapies following progression on frontline CDK4/6-inhibitor therapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS10-15.

The profound efficacy, yet associated toxicity of pan-BET inhibitors is well documented. The possibility of an ameliorated safety profile driven by significantly selective (>100-fold) inhibition of a subset of the eight bromodomains is enticing, but challenging given the close homology. Herein, we describe the X-ray crystal structure-directed optimization of a novel weak fragment ligand with a pan-second bromodomain (BD2) bias, to potent and highly BD2 selective inhibitors. A template hopping approach, enabled by our parallel research into an orthogonal template (15, GSK046), was the basis for the high selectivity observed. This culminated in two tool molecules, 20 (GSK620) and 56 (GSK549), which showed an anti-inflammatory phenotype in human whole blood, confirming their cellular target engagement. Excellent broad selectivity, developability, and in vivo oral pharmacokinetics characterize these tools, which we hope will be of broad utility to the field of epigenetics research.

Pan-bromodomain and extra terminal domain (BET) inhibitors interact equipotently with the eight bromodomains of the BET family of proteins and have shown profound efficacy in a number of in vitro phenotypic assays and in vivo pre-clinical models in inflammation or oncology. A number of these inhibitors have progressed to the clinic where pharmacology-driven adverse events have been reported. To better understand the contribution of each domain to their efficacy and improve their safety profile, selective inhibitors are required. This article discloses the profile of GSK046, also known as iBET-BD2, a highly selective inhibitor of the second bromodomains of the BET proteins that has undergone extensive pre-clinical in vitro and in vivo characterization.

Since 2016, eight new oligonucleotide therapies have been approved which has led to increased interest in oligonucleotide analysis. There is a particular need for powerful bioanalytical tools to study the metabolism and biotransformation of these molecules. This review provides the background on the biological basis of these molecules as currently used in therapies. The article also reviews the current state of analytical methodology including state of the art sample preparation techniques, liquid chromatography-mass spectrometry methods, and the current limits of detection/quantitation. Finally, the article summarizes the challenges in oligonucleotide bioanalysis and provides future perspectives for this emerging field. © 2020 John Wiley & Sons Ltd.

Herein, a series of 2,3-dihydrobenzofurans have been developed as highly potent bromo and extra-terminal domain (BET) inhibitors with 1000-fold selectivity for the second bromodomain (BD2) over the first bromodomain (BD1). Investment in the development of two orthogonal synthetic routes delivered inhibitors that were potent and selective but had raised in vitro clearance and suboptimal solubility. Insertion of a quaternary center into the 2,3-dihydrobenzofuran core blocked a key site of metabolism and improved the solubility. This led to the development of inhibitor 71 (GSK852): a potent, 1000-fold-selective, highly soluble compound with good in vivo rat and dog pharmacokinetics.

The profound efficacy of pan-BET inhibitors is well documented, but these epigenetic agents have shown pharmacology-driven toxicity in oncology clinical trials. The opportunity to identify inhibitors with an improved safety profile by selective targeting of a subset of the eight bromodomains of the BET family has triggered extensive medicinal chemistry efforts. In this article, we disclose the identification of potent and selective drug-like pan-BD2 inhibitors such as pyrazole 23 (GSK809) and furan 24 (GSK743) that were derived from the pyrrole fragment 6. We transpose the key learnings from a previous pyridone series (GSK620 2 as a representative example) to this novel class of inhibitors, which are characterized by significantly improved solubility relative to our previous research.

This technical note evaluated hybrid asphalt binders modified with a combination of styrene-butadyene-styrene (SBS) and postconsumer ground tire rubber (GTR). These hybrid blends were evalu...

Striga is a genus of parasitic plants that poses great danger to livelihoods of millions of smallholder farmers in sub-Saharan Africa by limiting production of staple cereals. The parasite attaches to the roots of the crop and establishes a vascular connection with the host’s xylem vessels in order to access water, organic and inorganic nutrients, leading to stunted growth and death of the infected plant. Mechanisms underpinning host–parasite interactions are not clearly understood making well-informed strategies for control of the parasite difficult. To facilitate studies of Striga–host interactions for molecular and genetic studies, we: (i) established an efficient protocol for growing Striga from seeds in tissue culture; (ii) optimized protocols for its regeneration through direct organogenesis and somatic embryogenesis, and (iii) determined the effect of co-culturing host and parasite in the same culture media. We found the best auxin and cytokinin concentrations to be: 10.7 μM naphthaleneacetic acid (NAA) and 2.2 μM 6-benzylaminopurine (BAP) for embryogenic callus regeneration and 1.1–4.4 μM BAP without NAA for shoot multiplication. While seedling, stem and leaf explants induced callus with the same frequency, seed radicles did not produce any callus. Unexpectedly, we found that when Striga callus was added in rice growing on culture media, the parasite adversely affected the host through formation of lesions on leaves and resulted in less shoot induction from callus in the parasite. Techniques described in this study will enhance further understanding of Striga–host interactions. Highly efficient protocols for tissue culture of the obligate parasitic plant Striga hermonthica and detection of host phytotoxicity by the parasite on culture media.

RIP1 kinase regulates necroptosis and inflammation and may play an important role in contributing to a variety of human pathologies, including inflammatory and neurological diseases. Currently, RIP1 kinase inhibitors have advanced into early clinical trials for evaluation in inflammatory diseases such as psoriasis, rheumatoid arthritis, and ulcerative colitis and neurological diseases such as amyotrophic lateral sclerosis and Alzheimer's disease. In this paper, we report on the design of potent and highly selective dihydropyrazole (DHP) RIP1 kinase inhibitors starting from a high-throughput screen and the lead-optimization of this series from a lead with minimal rat oral exposure to the identification of dihydropyrazole 77 with good pharmacokinetic profiles in multiple species. Additionally, we identified a potent murine RIP1 kinase inhibitor 76 as a valuable in vivo tool molecule suitable for evaluating the role of RIP1 kinase in chronic models of disease. DHP 76 showed efficacy in mouse models of both multiple sclerosis and human retinitis pigmentosa.

The voltage gated sodium channel NaV1.8 has been postulated to play a key role in the transmission of pain signals. Core hopping from our previously reported phenylimidazole leads has allowed the identification of a novel series of benzimidazole NaV1.8 blockers. Subsequent optimization allowed the identification of compound 9, PF-06305591, as a potent, highly selective blocker with an excellent preclinical in vitro ADME and safety profile.

A series of experiments were conducted to determine the chemical and physical differences between varieties of Starbon and activated carbon (AC). The adsorption process for all materials followed pseudo second order kinetics. High levels of adsorption were obtained for all materials; AC showed low levels of desorption for all bioactives over multiple washings, whereas the Starbons showed elevated desorption over the course of multiple washings.

Sum frequency generation (SFG) vibrational spectroscopy is used to characterize intermediate species of hydrogenation reactions on the surface of platinum nanoparticle catalysts. In contrast to other spectroscopy techniques which operate in ultra-high vacuum or probe surface species after reaction, SFG collects information under normal conditions as the reaction is taking place. Several systems have been studied previously using SFG on single crystals, notably alkene hydrogenation on Pt(111). In this thesis, many aspects of SFG experiments on colloidal nanoparticles are explored for the first time. To address spectral interference by the capping agent (PVP), three procedures are proposed: UV cleaning, H2 induced disordering and calcination (core-shell nanoparticles). UV cleaning and calcination physically destroy organic capping while disordering reduces SFG signal through a reversible structural change by PVP.Disordering is a dynamic and powerful way to perform SFG experiments on colloidal nanoparticles. Simply adding H2 (a reactant) to Pt-PVP reduces signal of PVP by >90%, making it possible to resolve intermediates. The selection rules of SFG indicate intensity may be reduced by a decrease in concentration or an increase in disorder. As H2 dissociates on Pt, the bond between PVP and Pt is weakened and PVP is able to rearrange into an unstructured geometry. Disordering makes size-controlled SFG studies possible for the first time because with PVP left intact, the nanoparticles are much less likely to aggregate. As evidence that a chemisorbed reaction intermediate is can be monitored, cyclohexene hydrogenation is performed. When PVP is disordered and the particles are "solvent-cleaned," the distinct C-H stretch of adsorbed 1,4-cyclohexadiene (1,4-CHD) appears at 2765 cm-1. In addition, the mechanism of hydrogenation of 1,3-butadiene (1,3-BD) at 75 °C is characterized using the disordering procedure. For larger Pt-PVP nanoparticles (4.6-6.7 nm), one major pathway is preferred (2-buten-1-yl). However, using smaller nanoparticles (0.9-1.8 nm), two major pathways exist (1-buten-4-yl and 2-buten-1-yl) and coincide with preference for full hydrogenation.Growth in the aliphatic stretch range following H2 dosing shows UV treatment is not able to produce "naked" nanoparticles. Although outer layers removed quickly, persistent C fragments remain near the Pt surface. The properties of residual fragments of PVP following UV treatment are very mystifying. PVP is known to block active sites on Pt and reduce turnover frequency for ethylene hydrogenation. (After three hours of UV treatment, ethylene hydrogenation increases tenfold.) However, it is shown that for methanol oxidation, residual fragments become impermeable and actually reduce the turnover rate. Under oxidation conditions, the regular capped Pt-PVP nanoparticles are more active than the same particles following PVP removal with UV treatment. As further evidence of this effect, cyclohexene hydrogenation is performed with different level of H2. Residual fragments are permeable with H2 and the 1,4-CHD intermediate appears in the SFG spectrum. However, once H2 is removed, chemisorbed 1,4-CHD completely disappears in favor of molecular (physisorbed) cyclohexene (not bonded to Pt). Even for a strongly bound dehydrogenated intermediate like 1,4-CHD, access to Pt is only possible with H2. Under varying amounts of UV treatment (PVP removal), the mechanism of cyclohexene hydrogenation varies widely among 1,4-CHD, 1,3-cyclohexadiene and pi-allyl. Removing PVP does not simply open equivalent sites but shifts the reaction mechanism in this case.Using Stöber encapsulation, a variety of PVP-capped catalysts can be coated in a thin porous SiO2 shell (5-10 nm) and used for in situ characterization. Surrounding the catalyst with SiO2 allows PVP to be thoroughly removed without compromising morphology. It is shown that alloying Pt with Sn (with SiO2 shell) allows a new reaction mechanism of CO oxidation to take place which is not limited by surface O2 concentration (as on pure Pt). In addition, 1,3-BD hydrogenation on 4 nm Pt@SiO2, Pd@SiO2 and Rh@SiO2 is studied with SFG. Previous work shows Pd makes only partially hydrogenated products while Pt makes all products. SFG and kinetic experiments indicate multiple pathways (1-butene-4-yl, butan-1,3-diyl and 2-buten-1-yl) are possible on Pt@SiO2 while only one (2-buten-1-yl) is favored on Pd@SiO2. This work is the first SFG reaction selectivity study on core-shell nanoparticles. Using catalysts inside SiO2 shells in dense 2-D films, it may become possible to assess industrial 3-D catalysts at a molecular level.

Mechanical properties of Novatein thermoplastic protein compounded at different extrusion temperatures and processing water contents have been examined in a factorial experiment. Thermoplastic proteins are moisture sensitive and can be prone to thermal degradation during processing. Processing water was varied between 30 and 45 parts per hundred parts bloodmeal while the extrusion temperature was varied between 120 and 150 °C to identify a processing window suitable for process scale up. To resolve any effects processing water had on protein-protein interactions from its plasticising effect, injection molded specimens were mechanically tested both as molded and after conditioning at controlled temperature and humidity. Despite all conditioned samples having approximately the same moisture content, mechanical properties were different. Tensile strength and modulus decreased with increasing processing water at the same equilibrium moisture content. DMA and WAXS suggested this was due to changes in chain mobility within the amorphous phase of the material, rather than conformational change towards a more ordered state. Properties of unconditioned specimens were mostly dependent on the plasticising effect of different amounts of processing water remaining in the material after injection molding. Extrusion temperature had very little effect on mechanical properties, suggesting that Novatein is robust enough to handle some temperature variations during processes such as injection molding.

Perinatal taurine depletion and high sugar intake from weaning onward worsen cardiac damage and arterial pressure control after ischemia/reperfusion (IR) in adult male and female rats, which can be ameliorated by high taurine diets or inhibition of renin-angiotensin system. This study tests if taurine supplementation ameliorates cardiac damage and arterial pressure control in adult female rats via alterations of both cardiac and systemic renin-angiotensin system. Female Sprague-Dawley rats were fed normal rat chow and drank water alone (control, C) or water containing 3% beta-alanine (taurine depletion, TD) from conception to weaning, and female offspring were subjected to high sugar intake (normal rat chow and 5% glucose in water; CG and TDG) or the normal rat diet (CW and TDW). At 7 weeks of age, half of the rats in each group received 3% taurine in water (CW+T, CG+T, TDW+T, and TDG+T). One week later, rats were subjected to IR or Sham procedures followed by renal nerve recording, plasma and cardiac angiotensin II measurements. Cardiac angiotensin II levels significantly elevated in CG, TDW, and TDG. Further, plasma angiotensin II concentrations were significantly elevated only in the TDG, in consistent with a significant increase in renal nerve activity to juxtaglomerular cells, but not renal vessels and tubules. These abnormalities were ameliorated by short-term taurine supplementation. Thus, in adult female rats that are perinatally depleted of taurine followed by high sugar intake after weaning, taurine supplementation decreases the adverse effects of cardiac IR via inhibition of both cardiac and systemic renin-angiotensin system overactivity.

Previous studies indicate that perinatal compromise of taurine causes cardiovascular disorders in adults via the influence of taurine on renin-angiotensin system (RAS). This study tested whether perinatal inhibition of the RAS would itself alter the adult cardiovascular system in a similar way. Female Sprague-Dawley rats were fed normal rat chow and given water alone (Control) or water containing captopril (400 mg/l) from conception until weaning. Then, the male offspring drank water or water containing captopril until 5 weeks of age followed by normal rat chow and water alone until 7 weeks of age. Thereafter, they drank water alone (Control, Captopril) or 1% NaCl solution (Control+1%, Captopril+1%). At 9 weeks of age, all animals were implanted with femoral arterial and venous catheters. Forty-eight hours later, blood chemistry, glucose tolerance, and hemodynamic parameters were determined in freely moving conscious rats. Then, the same experiments were repeated 2 days after captopril treatment. Body weights, kidney and heart to body weight ratios, fasting and non-fasting blood sugar, glucose tolerance, and heart rates were not significantly different among groups. Further, plasma sodium, mean arterial pressure, and sympathetic activity significantly increased whereas baroreflex sensitivity decreased in Captopril+1% compared to other groups. These changes were normalized by acute captopril treatment and the arterial pressure differences also by acute ganglionic and central adrenergic blockade. The present study suggests that inhibition of the RAS in the early life induces RAS overactivity, leading to salt-sensitive hypertension via sympathetic nervous system overactivity and depressed baroreflex sensitivity in adult male rats.

RATIONALE From allergies to plant reproduction, pollens have important impacts on the health of human and plant populations, yet identification of pollen grains remains difficult and time-consuming. Low-volatility flavonoids generated from pollens cannot be easily characterized and quantified with current analytical techniques. METHODS Here we present the novel use of atmospheric solids analysis probe mass spectrometry (ASAP-MS) for the characterization of flavonoids in pollens. Flavonoid patterns were generated for pollens collected from different plant types (trees and bushes) in addition to bee pollens from distinct geographic regions. Standard flavonoids (kaempferol and rhamnazin) and those produced from pollens were compared and assessed with ASAP-MS using low-energy collision MS/MS. Results for a semi-quantitative method for assessing the amount of a flavonoid in pollens are also presented. RESULTS Flavonoid patterns for pollen samples were distinct with variability in the number and relative abundance of flavonoids in each sample. Pollens contained 2-5 flavonoids, and all but Kochia scoparia contained kaempferol or kaempferol isomers. We establish this method as a reliable and applicable technique for analyzing low-volatility compounds with minimal sample preparation. Standard curves were generated using 0.2-5 μg of kaempferol; from these experiments, it was estimated that there is approximately 2 mg of kaempferol present in 1 g of P. nigra italica pollen. CONCLUSIONS Pollens can be characterized with a simple flavonoid pattern rather than analyzing the whole product pattern or the products-temperature profiles. ASAP-MS is a rapid analytical technique that can be used to distinguish between plant pollens and between bee pollens originating from different regions. Copyright © 2016 John Wiley & Sons, Ltd.

Atmospheric solid analysis probe mass spectrometry has the capability of capturing full product patterns simultaneously including both volatile and semi-volatile compounds produced at elevated temperatures. Real-time low-energy collision-induced fragmentation combined with ion mobility separations enables rapid identification of the chemical structures of products. We present here for the first time the recognition of full product patterns resulting from the thermal degradation of β-carotene at temperatures up to 600 °C. Solvent vapor-induced ionization enhancement is observed, which reveals parallel thermal dissociation processes that lead to even- and odd-numbered mass products. The drift-time distributions of high mass products, along with β-carotene, were monitored with temperature, showing multiple conformations that are associated with the presence of two β-rings. Products of masses 346/347, however, show a single conformation distribution, which indicates the separation of two β-rings resulting from the direct bond scission at the polyene hydrocarbon chain. The thermal degradation pathways are evaluated and discussed.

Sulfhemoglobinemia is a rare entity caused by irreversible sulfation of the heme moiety in haemoglobin to form sulfated haemoglobin (SulfHb) and has been caused by H2S arising from certain metabolites of drugs and bacterial infection. Clinical presentation is similar to that of methemoglobin (MetHb). Furthermore, it is often difficult to distinguish between the diagnosis of SulfHb from MetHb in arterial blood gas analysers due to the broad overlap in the optical density (OD) absorption spectra—that of SulfHb swamping the more distinct OD absorption shift seen with MetHb. The presence of SulfHb was suspected in a 73-year-old lady with low oxygen saturation (SaO2 ~75%), central cyanosis, and normal arterial oxygen partial pressure (pO2 ~12 kPa). Repeated arterial blood gas analysis on different systems returned error messages for MetHb quantification. There was an improvement in oxygen saturation and cyanosis after an exchange transfusion. A full OD spectrophotometry (500−700 nm) of the patient’s whole blood was suggestive of the presence of SulfHb, with a minor peak absorption at 620 nm. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF MS) was undertaken on whole blood samples from the patient pre- and post-transfusion, alongside normal controls. These demonstrated the presence of SulfHb in the patient’s blood, identifying sulfur, sulfur monoxide, and sulfur dioxide bound to the heme moiety. This gave vital identification as to the cause of Hb sulfation, which was distinct from that previously reported. Levels fell after the exchange transfusion and were completely eradicated after the correct source, an Epsom Salts constipation tonic, was identified. MALDI-ToF mass spectrometry is a new, rapid, specific, and sensitive diagnostic test for rare hematological syndromes such as SulfHb. In addition, it can identify the specific compounds bound to heme. Here, we provide useful diagnostic evidence as to the source of SulfHb, which was via SO2 rather than the previously described H2S.

A new method for reversed phase HPLC determination of thiamine and its major in vivo phosphorylation products, thiamine monophosphate (TMP) and thiamine pyrophosphate (TPP), was developed using tetrabutylammonium hydroxide as the ion-pairing agent. The separation was performed on a Phenomenex Kinetex EVO C18 column with a gradient of a phosphate-buffered aqueous solution of the ion-pair reagent and methanol. The duty cycle for the assay was 13 min and pyrithiamine was successfully used as the internal standard for the first time in a thiamine HPLC measurement protocol. Detection of the fluorescence derivatives of the analytes as well as the IS allowed for lower detection limits in order to support biological applications in cell culture models. The linearity, sensitivity, specificity, accuracy and precision of the method were evaluated and met the requirements specified by the US Food and Drug Administration. The calibration curves proved to be linear and the method was validated over the range from 1.0–4000 nm for both cells and the media where complete recovery of the analytes was also achieved. Copyright © 2015 John Wiley & Sons, Ltd.

Evaluated Weather Research and Forecasting model inline with chemistry (WRF/Chem) simulations of the 2009 Crazy Mountain Complex wildfire in Interior Alaska served as a testbed for typical Alaska wildfire-smoke conditions. A virtual unmanned air vehicle (UAV) sampled temperatures, dewpoint temperatures, primary inert and reactive gases and particular matter of different sizes as well as secondary pollutants from the WRF/Chem results using different sampling patterns, altitudes and speeds to investigate the impact of the sampling design on obtained mean distributions. In this experimental design, the WRF/Chem data served as the “grand truth” to assess the mean distributions from sampling. During frontal passage, the obtained mean distributions were sensitive to the flight patterns, speeds and heights. For inert constituents mean distributions from sampling agreed with the “grand truth” within a factor of two at 1000 m. Mean distributions of gases involved in photochemistry differed among flight patterns except for ozone. The diurnal cycle of these gases’ concentrations led to overestimation (underestimation) of 20 h means in areas of high (low) concentrations as compared to the “grand truth.” The mean ozone distribution was sensitive to the speed of the virtual UAV. Particulate matter showed the strongest sensitivity to the flight patterns, especially during precipitation.

The effect of sodium dodecyl sulfate (SDS) and triethylene glycol (TEG) on secondary structure of decolored bloodmeal (DBM) during heating was examined via synchrotron-based Fourier transform infra-red spectroscopy (FT-IR) and wide angle X-ray scattering (WAXS). Both additives homogenize secondary structure distribution; SDS increases α-helices and decreases β-sheets and β-turns, while SDS–TEG reduces α-helices and β-sheets and increase random coils. Short heat cycles only change the composition of SDS-TEG treated DBM, implying TEG is responsible for chain mobility. Prolonged heating slowly increases β-sheets and suddenly increases α-helices at 55–75 °C in SDS-TEG treated DBM and 100 °C in SDS-treated DBM. Finally, WAXS shows that structural change due to heating is reversible for SDS-TEG treated DBM.

Cylindrical 18650-type lithium-ion cells are being utilized more often for automotive applications. This introduces error in calculating expected lifetime due to varied usage conditions accelerating or reducing material damage. One such usage condition is vibration, which has been shown to impact the electrical performance over extended periods. Within this study X-ray photoelectron spectroscopy (XPS) has been performed on nickel manganese cobalt (NMC) cells subjected to vibration. This study found that vibration causes the removal of the selectively-formed surface film created during a cell’s first cycles and replaces it with the surface film from electrolyte decomposition. The surface films formed by vibration are composed of much higher concentrations of organic electrolyte decomposition products than the film from the control cell. The impact of this chemical mechanism is an increased level of cell degradation. This is exhibited in increased capacity fade and cell impedance. This is the first study presented within the academic literature which has identified an electro-mechanical mechanism responsible for the performance degradation in lithium-ion cells from vibration.

Even mild abnormalities of the renal structure or function can increase the risk of mortality and complications in other organs. Therefore, safe and effective treatments are necessary in order to influence the progression of renal disease. We used 2 methods to assess the renoprotective effects of aliskiren: 1) a statistical analysis of clinical trials that investigated aliskiren-induced renoprotection, in terms of changes in serum creatinine concentration (sCr) or estimated glomerular filtration rate (eGFR), and, 2) clinical trials that investigated the renoprotective effects of aliskiren with respect to changes in albuminuria or proteinuria. In the forest plot, the overall risk ratio (%) for renal impairment with respect to changes in sCr or eGFR was 0.97 (0.88-1.06; overall p=0.48). The tabulation of data from clinical trials included 10 entries for monotherapy with aliskiren and 6 entries for add-on aliskiren. All of the clinical trials, except one, showed a decrease in proteinuria or albuminuria following aliskiren treatment. In conclusion, inhibiting renin and prorenin with aliskiren is a more promising renoprotective treatment compared with blocking the renin/prorenin receptors (RPR). One of the main mechanisms by which aliskiren may confer renoprotection is by decreasing albuminuria and proteinuria. However, it does not seem to change sCr and eGFR in patients at risk of developing renal disease. Furthermore, co-administration of an angiotensinconverting- enzyme inhibitor (ACEI) or an angiotensin II receptor blocker (ARB) and aliskiren was shown to decrease albuminuria and proteinuria to a greater extent compared with monotherapy with these agents.

Bloodmeal can be decoloured using peracetic acid resulting in a material with a pale-yellow colour which only needs sodium dodecyl sulphate, water and triethylene glycol to extrude into a semi-transparent bioplastic. Fourier-transform infrared (FTIR) spectroscopy using Synchrotron light was used to investigate the effect of peracetic acid treatment at various concentrations on the spatial distribution of secondary structures within particles of bloodmeal. Oxidation caused aggregation of helical structures into sheets and acetic acid suppressed sheet formation. Decolouring with peracetic acid led to particles with a higher degree of disorder at the outer edges and higher proportions of ordered structures at the core, consistent with the expected diffusion controlled heterogeneous phase decolouring reaction. The degradation of stabilizing intra- and intermolecular interactions and the presence of acetate ions results in increased chain mobility and greater amorphous content in the material, as evidenced by reduction in Tg and greater enthalpy of relaxation with increasing PAA concentration.

Thermal analysis can generally be applied to protein-based thermoplastics although standard protein analysis techniques are not always possible to assess chain architecture. Blood (17% protein) from the meat industry can be fractionated or dried to blood meal, which can be converted to a thermoplastic called Novatein. The objective of this paper was to use a consistent methodology to compare different protein fractions from blood to that of blood meal, as well as the plastic produced from it, and how these changes relate to processing. Thermal properties were similar between protein fractions, but there were differences in chain conformation between blood meal, the haem containing fractions (red blood cells and spray dried haemoglobin) and the non-haem fractions (plasma and serum albumin). Blood meal is therefore best considered a single polymer, rather than the sum of its individual fractions. Thermoplastic processing reduces protein aggregation, and this phenomenon is more important than the behaviour of any of the individual proteins.

Nylon 6.6 containing 13C isotopic labels at specific positions along the macromolecular backbone has been subjected to extensive thermal-oxidative aging at 138 °C for time periods up to 243 days. In complementary experiments, unlabeled Nylon 6.6 was subjected to the same aging conditions under an atmosphere of 18O2. Volatile organic degradation products were analyzed by cryofocusing gas chromatography mass spectrometry (cryo-GC/MS) to identify the isotopic labeling. The labeling results, combined with basic considerations of free radical reaction chemistry, provided insights to the origin of degradation species, with respect to the macromolecular structure. A number of inferences on chemical mechanisms were drawn, based on 1) the presence (or absence) of the isotopic labels in the various products, 2) the location of the isotope within the product molecule, and 3) the relative abundance of products as indicated by large differences in peak intensities in the gas chromatogram. The overall degradation results can be understood in terms of free radical pathways originating from initial attacks on three different positions along the nylon chain which include hydrogen abstraction from: the (CH2) group adjacent to the nitrogen atom, at the (CH2) adjacent the carbonyl group, and direct radical attack on the carbonyl. Understanding the pathways which lead to Nylon 6.6 degradation ultimately provides new insight into changes that can be leveraged to detect and reduce early aging and minimize problems associated with material degradation.

Protein-based thermoplastics resemble semi-crystalline polymers, suggesting the occurrence of a glass transition (Tg) and melting point. Denaturing a protein's native structure is often called melting, but this does not necessarily imply complete unfolding into a fully amorphous structure as true melting would. Protein secondary structures, such as α-helices and β-sheets, can remain after denaturing, stay intact above the Tg and do not necessarily melt at typical processing temperatures. This implies that consolidation of aggregated protein particles into a macroscopically monolithic material depends on inter-chain interactions in the amorphous phase and on newly formed secondary structures. Structural relaxations and transition temperatures of the amorphous phase are influenced and constrained by the presence of these secondary structures as well as heavily influenced by plasticizers.

Synchrotron FT-IR micro-spectroscopy was used to determine thermally induced structural changes in thermoplastic protein produced from bloodmeal after mixing with sodium sulphite, sodium dodecyl sulphate, urea, tri-ethylene glycol and water. Changes in protein secondary structure at elevated temperature were assessed using second derivative peak height ratios in the amide III region (1,200–1,330 cm−1) and compared with DSC and DMA results over the same temperature range. The results show an increase in ordered β-sheet structures with temperature at the expense of random coils, and that these β-sheets do not melt in the temperature range up to extrusion temperature of 120 °C. The implication of this is that during melt processing, β-sheet clusters may remain intact, similar to dispersed particulate fillers.

Thermoplastic protein produced from bloodmeal (BM) becomes brittle as moisture desorbs from the material. Tensile tests, DMA, DSC and WAXS are used to determine the effect of replacing water with TEG. Specimens containing 0–30 pphBM TEG and combined water and TEG content prior to extrusion of 60 pphBM are extruded, injection-moulded and conditioned. TEG increases the strain at break while reducing strength. 20 pphBM is chosen as an appropriate compromise between strength and ductility with a tensile strength of 6 MPa, a Young's modulus of 250 MPa, a toughness of 2.8 MPa and a strain at break of 0.53. When TEG is held at 20 pphBM and the amounts of other additives varied urea has the largest effect on conditioned properties, showing that H-bonding still dominates protein/protein interactions.

Copper(II), iron(II), and manganese(II) complexes of 2-methyl-2-(2-pyridinyl)-1,3-propanediamine (ppda) were synthesized and characterized. The reaction of copper(II), iron(II), or manganese(II) salts with ppda yields complexes [Cu(ppda)Cl2] (1), [Cu(ppda)2](OTf)2 (2), [Fe(ppda)2](OTf)2 (3), and [Mn(ppda)2](OTf)2 (4). Complex 1 is square pyramidal with one molecule of ppda coordinated in a tridentate fashion with the amine N atoms and with chlorido ligands in the basal plane, and the pyridyl N atom in the axial position. Six-coordinate, C2-symmetrical complex 2 contains two ppda ligands with the pyridyl rings from two separate ppda ligands cis to each other in a tetragonally compressed square bipyramidal structure. The axial amine Cu–N bond distances are about 0.2 A shorter than the equatorial bonds. Solution EPR spectra of 2 at 77 and 298 K display typical axial signals suggesting a tetragonally elongated structure in solution. Librational disorder of the solid state structure points to crystal packing disorder in the solid state that leads to the slight axial compression, while the molecular structure in solution is the more typical d x 2 - y 2 ground state of an axially elongated structure. Complexes 3 and 4 are isostructural with 2 in terms of the disposition of the two ppda ligands. However, the bond distances for 3 are all very similar to each other (2.00 ± 0.04 A), and for 4 they are even more alike (2.25 ± 0.01 A).

Blood meal is a high protein, low value by-product of the meat processing industry that can be converted into a thermoplastic material by extrusion with a combination of a surfactant, urea, a reducing agent, water, and plasticiser. Changes in protein structure after each processing step (mixing with additives, extrusion, injection molding, and conditioning) were explored using synchrotron FTIR microspectroscopy. Blood meal particles were found to have higher β-sheet content around the perimeter with a randomly structured core. α-Helices were either located near the core or were evenly distributed throughout the particle. Structural rearrangement consistent with consolidation into a thermoplastic was seen after extrusion with processing additives, resulting in reduced α-helices and increased β-sheets. Including triethylene glycol as a plasticiser reduced α-helices and β-sheets in all processing steps. At all processing stages, regions with increased β-sheets could be identified suggesting blood meal-based thermoplastics should be considered as a semicrystalline polymer where clusters of crystalline regions are distributed throughout the disordered material. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Over the last decade, a number of computational methods have been developed, which attempt to evaluate the thermodynamic properties of individual water molecules at the solute-solvent interface, in order to assess contributions to protein-ligand binding. In some cases, these tools tell us what we already know, e.g. that hydrophobic pockets prefer lipophilic substituents, and in other cases the methods only seem to add clarity when retrospectively applied. Hence we have grappled with how to utilize such approaches to understand non-intuitive results and to generate chemistry ideas that otherwise would not have been developed. Here we provide our perspective on these methods and describe how results have been interpreted and applied. We include examples from GSK and elsewhere that highlight how water methods have been (1) utilized retrospectively to explain non-intuitive structure- activity relationships and (2) applied prospectively for chemistry design. Finally, we discuss where this field of study could lead to maximal impact in drug discovery research.