Methods to determine effects of cranberry proanthocyanidins on extraintestinal infections: Relevance for urinary tract health

Urinary tract infections (UTI) are one of the most frequent extraintestinal infections caused by Escherichia coli (ExPEC). Cranberry juice has been used for decades to alleviate symptoms and prevent recurrent UTI. The putative compounds in cranberries are proanthocyanidins (PAC), specifically PAC with “A‐type” bonds. Since PAC are not absorbed, their health benefits in UTI may occur through interactions at the mucosal surface in the gastrointestinal tract. Recent research showed that higher agglutination of ExPEC and reduced bacterial invasion are correlated with higher number of “A‐type” bonds and higher degree of polymerization of PAC. An understanding of PAC structure–activity relationship is becoming feasible due to advancements, not only in obtaining purified PAC fractions that allow accurate estimation, but also in high‐resolution MS methodologies, specifically, MALDI‐TOF MS. A recent MALDI‐TOF MS deconvolution method allows quantification of the ratios of “A‐type” to “B‐type” bonds enabling characteristic fingerprints. Moreover, the generation of fluorescently labeled PAC allows visualization of the interaction between ExPEC and PAC with microscopy. These tools can be used to establish structure–activity relationships between PAC and UTI and give insight on the mechanism of action of these compounds in the gut without being absorbed.     

Phenolics,fibre and fibre digestibility in the crop residue from bird resistant and non-bird resistant sorghum varieties

The relationship between phenolics and parameters of in-vitro digestibility of neutral-detergent fibre (NDF) in leaves and stems from the crop residue of bird resistant (BR) and non-bird resistant (NBR) sorghum varieties was determined. The phenolics studied were lignin, insoluble proanthocyanidins, soluble red pigments and soluble phenolics as measured by absorbance (280 nm)and precipitation with ytterbium. Parameters of the digestibility of NDF studied were 48-h digestibility, potentially digestible NDF, rate of digestion and indigestible NDF as determined by non-linear regression analysis. Leaves from BR varieties were higher in most phenolics than leaves from NBR varieties. Digestibility of NDF at 48 h, potentially digestible NDF and rate of NDF digestion was lower in leaves from BR varieties. The indigestible NDF was higher in BR varieties. Phenolics in leaves were negatively correlated with digestibility of NDF at 48 h, potentially digestible NDF and rate of NDF digestion and positively correlated with indigestible NDF. Phenolics in stems had non-significant correlations with parameters of the digestibility of NDF except for a positive correlation between lignin and indigestible NDF. These results indicate that breeding for bird resistance in sorghum would lead to lower nutritive value of the crop residue.     

Catalytic upgrading of tarry fuel gases: A kinetic study with model components

As a contribution to the development of a process for catalytic upgrading of tarry fuel gases, e.g. coke-oven gas, the conversion of naphthalene, benzene and methane on a nickel catalyst in the presence of H₂ and H₂O was studied. The experiments were performed in a tubular flow reactor (total pressure: 1.6 bar; residence time with respect to the empty reactor: 0.3 s; temperature: 400-950°C; and particle diameter of catalyst: 1.5 mm). The kinetic data were obtained by systematic variation of the reaction conditions.

At temperatures of more than 800°C, each hydrocarbon is cracked and converted with H₂O to CO and H₂. Soot formation does not occur at any temperature. In case of simultaneous conversion of all three hydrocarbons, competitive reactions have to be considered.

The rate of chemical reaction on the catalyst is substantially decreased in the presence of H₂S. Nevertheless, in a reactor of industrial scale, H₂S has only slight influence. The catalyst would be applied with a particle diameter of 19 mm (experiments: 1.5 mm), and the overall reaction rate of hydrocarbon conversion is significantly affected by gas film diffusion.     

Testing to determine relay seismic ruggedness

The seismic qualification of equipment in operating nuclear plants has been identified as a potential safety concern in U.S. Nuclear Regulatory Commission (USNRC) Unresolved Safety Issue (USI) A-46, “Seismic Qualification of Equipment in Operating Nuclear Power Plants”. In response to this concern, the Seismic Qualification Utility Group (SQUG), with support from the Electric Power Research Institute (EPRI), has undertaken a program to demonstrate the seismic adequacy of essential equipment by the use of actual experience with such equipment in plants which have undergone significant earthquakes and by the use of available test data for similar equipment. An important part of this program is the development of the methodology and test data for verifying the functionality of electrical relays used in essential circuits needed for plant shutdown during a seismic event. This paper describes the EPRI supported relay testing program to supplement existing relay test data. Many old relays which are used in safe shutdown systems of SQUG plants and for which seismic test data do not exist have been shake-table tested. The testing performed on these relays and the test results for two groups of relays are summarized in this paper.     

Neuroticism in relation to recovery and persisting pain after laparoscopic cholecystectomy

BACKGROUND: Persisting pain is seen in 20%-30% of patients after cholecystectomy for symptomatic gallbladder stones. The only preoperative factor that seems predictive is psychic vulnerability or neuroticism. Findings with regard to the influence of psychologic factors on recovery are contradictory, too. The aim of the present study was to examine a possible relationship between neuroticism and recovery and the outcome of operation. METHODS: Ninety-four patients who had had a laparoscopic cholecystectomy performed were tested psychologically with a Danish psychic vulnerability scale and with the Eysenck Neuroticism Scale before and 1 year after operation. The course of recovery was registered 1 month after operation, and outcome with regard to persisting pain 1 year postoperatively. RESULTS: No correlations were found between neuroticism scores and postoperative hospital stay or time to regain work/normal activities (P > 0.05). Persisting pain was found in 18% of the patients 1 year after operation. Although the patients with persisting pain had higher neuroticism scores preoperatively, the difference from the patients with successful outcome of the operation first became statistically significant 1 year postoperatively (P < 0.01-0.05). CONCLUSIONS: The results do not indicate that neuroticism influences the short recovery process after laparoscopic cholecystectomy. With regard to persisting pain, the higher neuroticism scores in these patients 1 year after the operation could be the consequence of the pain rather than aetiologic factors.     

Alkaline injection technology: Field demonstration

In December 2001, 2225 tonnes of fluidized bed combustion (FBC) ash were injected into an abandoned coal mine in eastern Oklahoma. Post-injection monitoring continued for 24 months, during which the mine system appeared to be reestablishing equilibrium with CO₂ in the mine headspace. Alkalinity and pH gradually increased, and as of December 2003 were roughly 65 ppm and 7.3, respectively. Metal concentrations were still significantly lower than pre-injection levels, but iron and manganese concentrations had increased from non-detect levels shortly after injection to roughly 30 ppm and 1.25 ppm, respectively. Aluminum, nickel, and zinc were less than pre-injection concentrations and did not appear to be increasing (roughly <PQL, 0.02 ppm, and 0.1 ppm, respectively). Arsenic and boron were not identified in concentrations that were of concern for protecting freshwater aquatic communities; however, selenium was well above the criterion continuous concentration and the maximum contaminant level. There were obvious improvements observed in the receiving environment—benthic habitat recovery and the return of fish species. However, additional monitoring is needed to determine the duration of the treatment and to evaluate the applicability of the treatment technology.     

Hydrogenation and Ring Opening of Aromatic and Naphthenic Hydrocarbons Over Noble Metal (Ir,Pt, Rh)/Al<Subscript>2</Subscript>O<Subscript>3</Subscript> Catalysts

Abstract  

The hydrogenation and ring opening of model hydrocarbons and of naphtha was studied over commercial noble metal (Ir, Pt, Rh)/Al₂O₃ catalysts. The experiments were performed in a fixed bed reactor at temperatures between 220 and 350 °C and pressures of 1.1 and 5.0 MPa, respectively. The product distribution was determined and the cetane number was calculated. The Pt catalyst is very active for hydrogenation of aromatics but does not catalyse the ring opening of naphthenes. The Ir and Rh catalysts are active for both hydrogenation of aromatics and ring opening of naphthenes. Experiments with toluene, m-xylene, propyl-benzene, and methylcyclohexane indicate that ring opening follows a selective mechanism, where the cleavage of bisecondary carbon bonds is favoured. This results in predominant formation of branched paraffins. The product distribution as well as cracking of long-chain hydrocarbons, which increase at temperatures above 260 °C, lead to an insignificant boost in the cetane number, as confirmed by experiments using real naphtha as feedstock.     

Deconvolution of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry isotope patterns to determine ratios of A-type to B-type interflavan bonds in cranberry proanthocyanidins

A method to deconvolute overlapping isotope patterns in positive mode matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was developed to determine ratios of A- to B-type interflavan bonds in proanthocyanidins that were isolated from cranberry (Vaccinium macrocarpon, Ait.) press cake (c-PAC). Precision and accuracy was validated for binary mixtures of procyanidins A2 and B2. Deconvolution of c-PAC spectra indicated that oligomers with one or more A-type interflavan bonds occur in a higher proportion than oligomers with all B-type interflavan bonds. c-PAC with at least one A-type bond accounted for more than 91% of the oligomers between trimers and undecamers. The c-PAC isotope patterns are highly repeatable, suggesting that the method can be applied to authentication, standardization and efficacy of cranberry products in relationship to urinary tract health. This is the first time MALDI-TOF MS has been used for estimating ratios of A- to B-type bonds in PAC.     

Ability of dietary antioxidants to affect lipid oxidation of cooked turkey meat in a simulated stomach and blood lipids after a meal

Oxidized lipids that form during digestion of a meal have the potential to promote reactions that incur vascular disease. A grape seed extract (1% of the meat weight) and butylated hydroxytoluene (0.2% of the lipid weight) were each effective at preventing formation of lipid oxidation products for 3 h during co-incubation with cooked turkey meat in simulated gastric fluid (SGF). Grape seed extract (GSE) at 0.1% of the meat weight accelerated lipid peroxide formation in SGF. Increasing concentrations of GSE decreased the ability of iron to partition into isolated microsomes. Swine trials were conducted in which cooked meat or cooked meat with added antioxidants were fed (seven meals during seven days). Lipid oxidation products were measured in chylomicrons from blood samples that were withdrawn 3 and 4 h after the last meal. Each of the antioxidant treatments that prevented lipid oxidation in SGF also inhibited formation of conjugated dienes in blood chylomicrons (P < 0.05). Mechanisms of polyphenol effects are discussed.