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111.
Kiecolt-Glaser Janice K.; Glaser Ronald; Williger Daniel; Stout Julie; Messick George; Sheppard Sharon; Ricker Denise; Romisher Stephen C.; Briner William; Bonnell George; Donnerberg Roy 《Canadian Metallurgical Quarterly》1985,4(1):25
Assessed the enhancement of immunocompetence by relaxation and social contact in 45 60–88 yr old geriatric residents of independent-living facilities. Ss were randomly assigned to 1 of 3 protocols: (1) relaxation training, (2) social contact, or (3) no contact. Ss in the relaxation and social-contact conditions were seen individually 3 times/wk for 1 mo. Blood samples and self-report data were obtained at baseline, at the end of the intervention, and at a 1-mo follow-up. At the end of the intervention, Ss in the relaxation group, who had been taught progressive relaxation and guided imagery as an active coping skill, showed a significant increase in natural killer cell activity and significant decreases in antibody titers to Herpes simplex virus and self-rated distress. The other 2 groups showed nonsignificant changes. There was a general increase in the T-lymphocyte response to phytohemagglutinin stimulation at the end of the intervention, with greater change at lower mitogen concentrations. Data suggest that cellular immunocompetence may be enhanced by psychosocial interventions. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
Donald E. Johnston Denise Kelly Pauline P. Dorrian 《Journal of the science of food and agriculture》1983,34(7):733-736
Differences in the extent of loss of pectic substances from potato (Solanum tuberosum L.) after boiling, steaming and pressure cooking were investigated. Losses were found to be significantly greater (P< 0.001) after boiling than after pressure cooking or steaming. The pectic substance content (g 100 g?1 dry matter) of potatoes (cv. Pentland Crown) was 2.98 for raw peeled tubers, 0.97 after boiling for 35 min, 1.22 after steaming for 35 min and 1.24 after pressure cooking at 103.4 kPa (15 psi) for 15 min. The roles of cooking time, cooking temperature and heat transfer medium are discussed. The effects of calcium sulphate (at levels typical of ‘hard’ and ‘soft’ water supplies) in the cooking water on losses of pectic substances from potato (Solanum tuberosum L.), carrot (Daucus carota L.), and swede (Brassica napus L. var. napobrassica Peterm.) after boiling and pressure cooking were also investigated. Water hardness did not influence losses during pressure cooking but samples boiled in hard water had decreased losses of pectic substances compared to those boiled in soft water. The increase in retention of pectic substances due to hard water was about 8 % for potatoes (cv. Pentland Dell), about 33 % for sliced carrots (cv. Berlicum, approved maintenance Perfecta) and about 23% for diced swedes (cv. Acme). The interaction of water hardness with cooking method was significant for potato (P< 0.05) and swede (P<0.001) and approaching significance (P=0.055) for carrot. 相似文献
113.
The response of a potential nonpathogenic surrogate organism to a particular treatment should closely mimic the response of the target pathogenic organism. In this study, growth characteristics (generation time, lag phase duration, and maximum population), pH at stationary phase, and survival characteristics (level of attachment and survival on apple surfaces, resistance to hydrogen peroxide decontamination treatments, and thermal resistance at 60 degrees C) of 15 nonpathogenic generic Escherichia coli strains and one nonpathogenic E. coli O157:H43 strain were compared with those of two E. coli O157:H7 strains and two Salmonella strains. Few differences in growth characteristics or pH at stationary phase were evident between nonpathogenic and pathogenic strains tested. However, considerably more separation among strains was seen following investigation of survival characteristics. E. coli ECRC 97.0152, which does not contain genes encoding for known virulence factors associated with E. coli O157:H7, appears to be a good surrogate candidate, with growth and survival characteristics similar to those of E. coli O157:H7 strains. The less heat-resistant surrogate strains E. coli NRRL B-766 and NRRL B-3054 and E. coli ATCC 11775, ATCC 25253, and ATCC 25922 may be used when attempting to model the heat resistance of Salmonella Montevideo G4639 and Salmonella Poona RM 2350, respectively. These surrogate strains may be useful for evaluating the efficacy of intervention steps in reducing populations of selected strains of E. coli O157:H7 and Salmonella in processing environments where these pathogens cannot be introduced. 相似文献
114.
The dominant theory in the field of mammalian herbivore–plant interactions is that intake, and therefore tolerance, of plant secondary metabolites (PSMs) is regulated by mechanisms that reduce absorption and increase detoxification of PSMs. Methods designed by pharmacologists to measure detoxification enzyme activity, metabolite excretion, and most recently, drug absorption, have been successfully applied by ecologists to study PSM intake in a variety of mammalian study systems. Here, we describe several pharmacological and molecular techniques used to investigate the fate of drugs in human that have potential to further advance knowledge of mammalian herbivore–plant interactions. 相似文献
115.
Stone ME Scott JW Schultz ST Berry DL Wilcoxon M Piwoni M Panno B Bordson G 《The Science of the total environment》2009,407(2):770-775
The purpose of this project was to compare the ability of chlorine (HOCl/OCl−) and monochloramine (NH2Cl) to mobilize mercury from dental amalgam. Two types of amalgam were used in this investigation: laboratory-prepared amalgam and samples obtained from dental-unit wastewater. For disinfectant exposure simulations, 0.5 g of either the laboratory-generated or clinically obtained amalgam waste was added to 250 mL amber bottles. The amalgam samples were agitated by end-over-end rotation at 30 rpm in the presence of 1 mg/L chlorine, 10 mg/L chlorine, 1 mg/L monochloramine, 10 mg/L monochloramine, or deionized water for intervals of 0 h, 2 h, 4 h, 8 h, and 24 h for the clinically obtained amalgam waste samples and 4 h and 24 h for the laboratory-prepared samples. Chlorine and monochloramine concentrations were measured with a spectrophotometer. Samples were filtered through a 0.45 µm membrane filter and analyzed for mercury with USEPA standard method 245.7. When the two sample types were combined, the mean mercury level in the 1 mg/L chlorine group was 0.020 mg/L (n = 25, SD = 0.008). The 10 mg/L chlorine group had a mean mercury concentration of 0.59 mg/L (n = 25, SD = 1.06). The 1 mg/L chloramine group had a mean mercury level of 0.023 mg/L (n = 25, SD = 0.010). The 10 mg/L chloramine group had a mean mercury level of 0.024 mg/L (n = 25, SD = 0.011). Independent samples t-tests showed that there was a significant difference between the natural log mercury measurements of 10 mg/L chlorine compared to those of 1 mg/L and 10 mg/L chloramine. Changing from chlorine to chloramine disinfection at water treatment plants would not be expected to produce substantial increases in dissolved mercury levels in dental-unit wastewater. 相似文献
116.
Ana Cristina C.F. Sieira Denise M.S. Gerscovich Alberto S.F.J. Sayão 《Geotextiles and Geomembranes》2009
Reinforcing elements embedded within soil mass improve stabilization through a load transfer mechanism between the soil and the reinforcement. Geogrids are a type of geosynthetic frequently used for soil reinforcement, consisting of equally spaced longitudinal and transverse ribs. Under pullout conditions, the longitudinal ribs are responsible for tensile resistance, while transverse ribs contribute to a passive resistance. This paper describes a new analytical model capable of reproducing both load transfer and displacement mechanisms on the geogrid length, under pullout conditions. The model subdivides the geogrid into rheological units, composed by friction/adhesion and spring elements, mounted in line. Friction/adhesion elements respond to the shear component mobilized at the soil–geogrid interface. Spring elements respond to the geogrid's tensile elongation. Model parameters are obtained through tensile strength tests on geogrids and conventional direct shear tests on soil specimens. The need for instrumented pullout tests becomes therefore eliminated. Results predicted from this new model were compared to instrumented pullout test data from two types of geogrids, under various confining stress levels. The results revealed that the new model is capable of reasonably predicting load and displacement distributions along the geogrid. 相似文献
117.
Maximiliano Soares Pinto Antnio Fernandes de Carvalho Ana Clarissa dos Santos Pires Junio Cesar Jacinto de Paula Denise Sobral Fernando Antnio Resplande Magalhes 《Food Control》2009,20(12):1167-1170
Cheese produced with raw milk can be a risk to consumer health. It is known that lactic acid bacteria present in raw milk and in natural starters can produce antimicrobial compounds against some foodborne bacteria. This work aimed to evaluate the survival of Listeria innocua in Minas Traditional Serro cheese during cheese ripening. The cheeses were inoculated with 101, 102 or 103 CFU mL−1 of the bacterium and were analyzed for 60 days of ripening at 30 °C. It was observed that the time and the dose of bacteria inoculated affected (p < 0.05) the survival of L. innocua. Even when the lowest dose was inoculated, at the end of the 60 days, approximately 102 CFU mL−1 of L. innocua was detected in the cheese. The lactic acid bacteria present in the milk and in the natural starter were not sufficient to guarantee the absence of L. innocua in Minas Traditional Serro cheese even after 60 days of storage, as is required by Brazilian legislation. 相似文献
118.
Samuel Furse Denise S. Fernandez-Twinn Davide Chiarugi Albert Koulman Susan E. Ozanne 《International journal of molecular sciences》2021,22(14)
The aim of the current study was to test the hypothesis that maternal lipid metabolism was modulated during normal pregnancy and that these modulations are altered in gestational diabetes mellitus (GDM). We tested this hypothesis using an established mouse model of diet-induced obesity with pregnancy-associated loss of glucose tolerance and a novel lipid analysis tool, Lipid Traffic Analysis, that uses the temporal distribution of lipids to identify differences in the control of lipid metabolism through a time course. Our results suggest that the start of pregnancy is associated with several changes in lipid metabolism, including fewer variables associated with de novo lipogenesis and fewer PUFA-containing lipids in the circulation. Several of the changes in lipid metabolism in healthy pregnancies were less apparent or occurred later in dams who developed GDM. Some changes in maternal lipid metabolism in the obese-GDM group were so late as to only occur as the control dams’ systems began to switch back towards the non-pregnant state. These results demonstrate that lipid metabolism is modulated in healthy pregnancy and the timing of these changes is altered in GDM pregnancies. These findings raise important questions about how lipid metabolism contributes to changes in metabolism during healthy pregnancies. Furthermore, as alterations in the lipidome are present before the loss of glucose tolerance, they could contribute to the development of GDM mechanistically. 相似文献
119.
Lorenzo Ball Emanuela Barisione Luca Mastracci Michela Campora Delfina Costa Chiara Robba Denise Battaglini Marco Micali Federico Costantino Giuseppe Cittadini Nicol Patroniti Paolo Pelosi Roberto Fiocca Federica Grillo 《International journal of molecular sciences》2021,22(14)
Lung fibrosis has specific computed tomography (CT) findings and represents a common finding in advanced COVID-19 pneumonia whose reversibility has been poorly investigated. The aim of this study was to quantify the extension of collagen deposition and aeration in postmortem cryobiopsies of critically ill COVID-19 patients and to describe the correlations with qualitative and quantitative analyses of lung CT. Postmortem transbronchial cryobiopsy samples were obtained, formalin fixed, paraffin embedded and stained with Sirius red to quantify collagen deposition, defining fibrotic samples as those with collagen deposition above 10%. Lung CT images were analyzed qualitatively with a radiographic score and quantitatively with computer-based analysis at the lobe level. Thirty samples from 10 patients with COVID-19 pneumonia deceased during invasive mechanical ventilation were included in this study. The median [interquartile range] percent collagen extension was 6.8% (4.6–16.2%). In fibrotic compared to nonfibrotic samples, the qualitative score was higher (260 (250–290) vs. 190 (120–270), p = 0.036) while the gas fraction was lower (0.46 (0.32–0.47) vs. 0.59 (0.37–0.68), p = 0.047). A radiographic score above 230 had 100% sensitivity (95% confidence interval, CI: 66.4% to 100%) and 66.7% specificity (95% CI: 41.0% to 92.3%) to detect fibrotic samples, while a gas fraction below 0.57 had 100% sensitivity (95% CI: 66.4% to 100%) and 57.1% specificity (95% CI: 26.3% to 88.0%). In COVID-19 pneumonia, qualitative and quantitative analyses of lung CT images have high sensitivity but moderate to low specificity to detect histopathological fibrosis. Pseudofibrotic CT findings do not always correspond to increased collagen deposition. 相似文献
120.
Denise Daigle Leblanc Lita Villalon 《Revue canadienne de la pratique et de la recherche en diététique》2008,69(3):133-140
Objectif. Mesurer et analyser le lien entre le stress per?u et le comportement alimentaire d'étudiants de première (Et1) et de quatrième année (Et4) à l'Université de Moncton au début (T1) et à la fin (T2) du trimestre universitaire. Méthodes. Quatre-vingt-quatorze sujets de divers programmes universitaires ont participé à l'étude. Le stress per?u a été mesuré à l'aide de la Perceived Stress Scale, la consommation alimentaire par un journal alimentaire de trois jours et la fréquence de consommation alimentaire par un questionnaire de fréquence. Résultats. Au début du trimestre, les Et1 et Et4 présentent un niveau de stress faible. Au T2, le stress per?u des Et4 augmente significativement (22,3+/-1,4; p=0,005). Le profil alimentaire mesuré selon le niveau de conformité au "Guide alimentaire canadien pour manger sainement" montre, avec l'accroissement du stress, une augmentation de la consommation de lait et produits laitiers (p=0,05) chez les Et1,T1 et de produits céréaliers (p=0,02) chez les Et4,T2. Une corrélation négative significative est observée chez les Et4 entre le stress per?u et l'ingestion de thiamine (r=-0,48, p=0,006) et de zinc (r=-0,42, p=0,02). Aucune corrélation n'est observée entre le stress, l'apport en calories et la consommation des autres nutriments étudiés. Conclusion. Ces résultats révèlent l'importance d'intervenir auprès des étudiants universitaires et d'implanter des sessions d'information favorisant la gestion du stress et l'adoption de comportements alimentaires sains. 相似文献