Trevor J. Rook

NITRIC OXIDE METABOLITES IN NORMAL HUMAN PREGNANCY AND PREECLAMPSIA

Objective: Alterations in the vascular endothelial release of nitric oxide (NO) may contribute to the vasodilatory adaptation to normal pregnancy and to the vasoconstriction associated with preeclampsia. The aim of this study was to investigate these hypotheses by measuring plasma levels of the stable metabolites of NO, nitrite and nitrate, during normal human pregnancy and those complicated by preeclampsia.Methods: Plasma samples were obtained from women in the following groups: nonpregnant; normal first-, second-, and third-trimester pregnant; and preeclamptic. Nitrite concentrations in the samples were determined using a colorimetric assay. Nitrate concentrations were determined using anion-exchange chromatography with UV detection.Results: The plasma nitrite and nitrate concentrations of normal pregnant women (9.45 ± 0.58 u.M. n = 59. and 85 ± 8 µM, n = 29, respectively) were not significantly different from those of nonpregnant women (10.04 ± 1.47 µM, n = 10, and 95 ± 15 µM, n = 9, respectively), and...

Crystallization and melting of highly filled polypropylene composites prepared with surface-treated fillers

Polypropylene (PP) composites with high filler content have been prepared with surface-treated fillers. The effect of the filler is twofold; nucleation of crystallization occurs, though the PP is also adsorbed onto the filler thereby retarding its motion. Differential scanning calorimetry has been used to study the crystallization of the PP. Melting and recrystallization during melting has been characterized by differential scanning calorimetry. The properties of the composites are more than an additive combination of the filler and polymer. In the case of highly filled composites, the morphology of the PP is important in limiting brittleness and for the strength of the interface between filler and polymer. Surface treatment of the filler has been found to have a significant control over the morphology and properties of the composites.

A non-fullerene electron acceptor based on central carbazole and terminal diketopyrrolopyrrole functionalities for efficient, reproducible and solution-processable bulk-heterojunction devices

A novel, solution-processable non-fullerene electron acceptor, 6,6′-((9-(heptadecan-9-yl)-9H-carbazole-2,7-diyl)bis(thiophene-5,2-diyl))bis(2,5-bis(2-ethylhexyl)-3-(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (coded as N7), based on central carbazole and terminal diketopyrrolopyrrole building blocks was designed, synthesized and characterized. N7 displayed excellent solubility, thanks to its design allowing incorporation of numerous lipophilic chains, thermal stability, and afforded a 2.30% power conversion efficiency with a high open-circuit voltage (1.17 V) when tested with the conventional donor polymer poly(3-hexylthiophene) in solution-processable bulk-heterojunction devices. To our knowledge, not only is N7 the first reported chromophore based on carbazole and diketopyrrolopyrrole functionalities but the open-circuit voltage reported here is among the highest values for a single junction bulk-heterojunction device that has been fabricated using a simple device architecture, with reproducible outcomes and with no special treatment.

Studies towards the synthesis of Salvinorin A

Salvinorin A 1, a psychoactive neoclerodane diterpenoid from the Mexican sage S. divinorum, has gained interest as a selective κ-opioid receptor agonist. Non-racemic 3-furylamines 9a and 9b have been prepared from (+)-pseudoephedrine and (–)-ephedrine for application in the stereoselective synthesis of the ketone ring of 1. Diels–Alder reaction of 9b with methyl acrylate in aqueous media, followed by selective ether bridge cleavage, has allowed access to the cyclohexenone 17 with preservation of stereochemistry at C2. A model route to the lactone ring has also been achieved through a one-pot deconjugation/esterification procedure of 2-bromocrotonyl chloride 20 to the furyl alcohol 19 followed by Reformatski-mediated ring closure.

Processing and properties of polypropylene composites with high filler content

Highly filled polypropylene composites have been prepared with filler contents up to 43.8 vol.% (70 wt.%) after surface treatment of the fillers with titanate or silicone. The fillers used were calcium carbonate, talc and barium sulfate. Surface modification of the fillers facilitated extrusion and reduced brittleness while providing hard composites with high density. The high density and hardness provide a texture which is not characteristic of polypropylenes, but more like thermoset composites or ceramics; yet the composites can be extruded using typical thermoplastic processing equipment. The composition has been measured by thermogravimetry, and morphology observed with scanning electron microscopy. The tensile properties were measured and related to the composition, filler type and surface treatment.

Synthesis of Some 3-Furylamine Derivatives

A general and efficient method for the synthesis of 3-furylamines via Michael addition of amines to acyclic keto alkynol precursors has been achieved. The preparation of various 3-furylamines has been carried out using a flexible methodology which also allows modification of the substituent at the 5-position.

Rheology of highly filled polypropylenes prepared with surface treated fillers

Highly filled polypropylene (PP) composites have been produced by extrusion of polypropylenes with surface treated fillers. The aim is to include the highest proportion of filler that can provide hardness and high density, without undue brittleness. Modification of the filler surface provided significant enhancement of the processing properties that have been studied with parallel plate rheometry. The experimental results indicated that the viscoelastic behavior of melt flow of highly filled polypropylene composites significantly depended on the following properties of the fillers: aspect ratio, specific surface area and particle size in talc, calcium carbonate and barium sulfate filled polypropylene composites. Traditional surface modifiers such as stearic acid are useful, but titanates and in particular small amounts of silicones have provided the greatest rheological modification.

Diels-Alder reactions of 3-furylamines in organic and aqueous solvents

Various 5-methyl-3-aminofurans have been shown to undergo facile Diels-Alder reactions with methyl acrylate in aqueous media. Reactions proceeded with exclusive regiochemistry, and enamine cycloadducts were readily hydrolyzed to afford 7-oxabicyclo[2.2.1]heptanones in high yields.

Dietary Directions Against Dementia Disorders

Since human health benefits are influenced by diets and lifestyle, the dietary intake and body–brain interactions of phytochemicals which are abundant in fruits, berries, vegetables, herbs, and in beverages are a promising avenue and resource that can provide dietary intervention and protection strategies against Alzheimer’s disease, Parkinson disease, Huntington disease, and Amyotrophic Lateral Sclerosis dementia diseases. The manipulation of the molecular mechanisms and metabolic processes of food consumption occurring in body and brain can direct, determine, and provide new strategies of how to optimize and select dietary constituents that may sustainably provide generic benefits for neurons to defend against insults and damage, and sustain mental fitness against all neurodegenerative diseases. This chapter provides a perspective of the molecular episodes of dietary phytochemicals including polyphenols, brain foods/beverages, and herbs that can be used and directed towards providing health-sustaining interventions against protein misfolding-neurodegenerative and dementia disorders.