Home About us Contact
|
Home About us Contact | ||
|
|
||
Decreasing Levels (decreasing + level)
Selected AbstractsRelationship between stump treatment coverage using the biological control product PG Suspension, and control of Heterobasidion annosum on Corsican pine, Pinus nigra ssp. laricioFOREST PATHOLOGY, Issue 1 2008K. V. Tubby Summary The relationship between the proportion of the stump surface covered by the biological stump treatment agent PG Suspension, containing Phlebiopsis gigantea and its efficacy against the pathogen Heterobasidion annosum sensu stricto was studied during a first thinning of Corsican pine (Pinus nigra ssp. laricio) in Thetford Forest, UK. PG Suspension was manually applied to 100%, 75%, 50% or 0% of the surface of 150 stumps. Spores of H. annosum were inoculated onto 75 of the stumps, and the remaining stumps exposed to natural airborne spore deposition. The relationship between coverage and efficacy was found to be quantitative. Covering all the stump surface with PG Suspension completely excluded the pathogen, whereas stumps not treated with PG Suspension (the 0% treatment) became infected with H. annosum. Partial (75%) PG Suspension coverage resulted in the pathogen colonizing 40% of stumps following artificial inoculation with H. annosum, and just 7% of stumps exposed to ambient H. annosum spore infection. Decreasing levels of coverage allowed increasing areas of the stump surface to be colonized by H. annosum. Some small gaps in coverage were closed by lateral growth of P. gigantea, but it is recommended that operators aim for full stump coverage to give complete protection against H. annosum. [source] Food Security in Complex Emergencies: Enhancing Food System ResilienceDISASTERS, Issue 2005Prabhu Pingali This paper explores linkages between food security and crisis in different contexts, outlining the policy and institutional conditions needed to manage food security during a crisis and to rebuild the resilience of food systems in periods of relative peace. The paper reviews experiences over the past decade of countries in protracted crisis and draws lessons for national and international policy. It assesses the different alternatives on offer in fragile countries to address, for example, the disruption of institutional mechanisms and the decreasing level of support offered by international donors with respect to longer-term expectations. It proposes a Twin Track Approach to enhance food security resilience through specific policies for protracted crises that link immediate hunger relief interventions with a long-term strategy for sustainable growth. Finally, the article analyses policy options and the implications for both short- and longer-term responses vis-à-vis the three dimensions of food security: availability; access; and stability. [source] Stability of decisional role preference over the course of cancer therapyPSYCHO-ONCOLOGY, Issue 4 2006Julie B. Mallinger Abstract Cancer patients vary in their preferred level of involvement in medical decision making, and responding to patients' desired level of involvement is a key element of good medical care. While the literature has clearly demonstrated heterogeneity among cancer patients' preferences, less is known about how the preferences of any given patient may change over time. This longitudinal study compared cancer patients' preferences for involvement in medical decision making from the time of diagnosis to the time of completion of therapy. Data from 729 cancer patients with mixed diagnoses were analyzed. Most patients reported a change in preferred level of involvement over time, and multivariate analysis demonstrated that patients tend to prefer a decreasing level of involvement over time (p<0.0001). Stability of patients' preferences was also associated with type of cancer, but not with other sociodemographic characteristics. The results from this study highlight the importance of reevaluating patients' preferences for involvement in medical decision making throughout the course of cancer therapy, as such preferences are likely to change. Copyright © 2005 John Wiley & Sons, Ltd. [source] Ischaemic preconditioning is related to decreasing levels of extracellular adenosine that may be metabolically useful in the at-risk myocardium: an experimental study in the pigACTA PHYSIOLOGICA, Issue 1 2010A. Waldenström Abstract Aim:, ,Pre-treatment' with short repetitive periods of ischaemia (ischaemic preconditioning) has proved to be a powerful mechanism for modification of the extent of myocardial damage following acute coronary artery occlusion. The exact mechanism of protection induced by ischaemic preconditioning is not known. We herewith put forward a contributing component for protection with preconditioning involving a shift in the adenylate kinase (AK) equilibrium reaction in favour of adenosine triphosphate (ATP) formation. Methods:, A coronary artery was occluded in anaesthetized thoracotomized pigs to induce ischaemic preconditioning as well as a longer period of ischaemia. Microdialysis probes were inserted in ischaemic and control myocardium and were infused with 14C- adenosine with two different specific activities. 14C-lactate was identified and measured in the effluent. Results:,14C-adenosine was taken up by non-preconditioned and preconditioned myocardium during ischaemia. Significantly increased levels of 14C-lactate were recovered in preconditioned myocardium. 14C-adenosine with high specific activity resulted in a specific activity of lactate that was 2.7 times higher than that of lactate after administration of 14C-adenosine with low specific activity. Mass spectrography verified the identity of 14C-lactate. Conclusions:, Preconditioning up-regulates a new metabolic pathway (starting with 5,-nucleotidase and ending up with lactate) resulting in ATP formation in the micromolar range on top of another effect terminating in a useful shift in the AK equilibrium reaction in favour of ATP generation in the millimolar range. Although the up-regulation of the purine nucleoside phosphorylase pathway is clearly demonstrated, its biological relevance remains to be proved. [source] Trajectories of resilience over 25 years of individuals who as adolescents consulted for substance misuse and a matched comparison groupADDICTION, Issue 7 2010Peter Larm ABSTRACT Aims To examine trajectories of resilience over 25 years among individuals who as adolescents received treatment for substance misuse, the clinical sample (CS) and a matched general population sample (GP). Design Comparison of the CS and GP over 25 years using Swedish national registers of health care and criminality. Setting A substance misuse clinic for adolescents in an urban area in Sweden. Measurements Resilience was defined as the absence of substance misuse, hospitalizations for physical illnesses related to substance misuse, hospitalization for mental illness and law-abiding behaviour from ages 21 to 45 years. Participants The CS included 701 individuals who as adolescents had consulted a clinic for substance misuse. The GP included 731 individuals selected randomly from the Swedish population and matched for age, sex and birthplace. Findings A total of 52.4% of the GP and 24.4% of the CS achieved resilience in all domains through 25 years. Among the CS, another one-third initially displayed moderate levels of resilience that rose to high levels over time, one-quarter displayed decreasing levels of resilience over time, while 9.3% showed little but improving resilience and 8.8% showed no resilience. Levels of resilience were associated with the severity of substance misuse and delinquency in adolescence. Conclusions Individuals who had presented substance misuse problems in adolescence were less likely to achieve resilience over the subsequent 25 years than was a matched general population sample, and among them, four distinct trajectories of resilience were identified. The severity and type of problems presented in adolescence distinguished the four trajectories. [source] Cell cycle checkpoints and their impact on anticancer therapeutic strategiesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2004Alan Eastman Abstract Cells contain numerous pathways designed to protect them from the genomic instability or toxicity that can result when their DNA is damaged. The p53 tumor suppressor is particularly important for regulating passage through G1 phase of the cell cycle, while other checkpoint regulators are important for arrest in S and G2 phase. Tumor cells often exhibit defects in these checkpoint proteins, which can lead to hypersensitivity; proteins in this class include ataxia,telangiectasia mutatated (ATM), Meiotic recanbination 11 (Mre11), Nijmegen breakage syndrome 1 (Nbs 1), breast cancer susceptibility genes 1 and 2 (BRCA1), and (BRCA2). Consequently, tumors should be assessed for these specific defects, and specific therapy prescribed that has high probability of inducing response. Tumors defective in p53 are frequently considered resistant to apoptosis, yet this defect also provides an opportunity for targeted therapy. When their DNA is damaged, p53-defective tumor cells preferentially arrest in S or G2 phase where they are susceptible to checkpoint inhibitors such as caffeine and UCN-01. These inhibitors preferentially abrogate cell cycle arrest in p53-defective cells, driving them through a lethal mitosis. Wild type p53 can prevent abrogation of arrest by elevating levels of p21waf1 and decreasing levels of cyclins A and B. During tumorigenesis, tumor cells frequently loose checkpoint controls and this facilitates the development of the tumor. However, these defects also represent an Achilles heel that can be targeted to improve current therapeutic strategies. © 2003 Wiley-Liss, Inc. [source] Effects of Size of Cellulose Granules on Dough Rheology, Microscopy, and Breadmaking PropertiesJOURNAL OF FOOD SCIENCE, Issue 2 2007M. Seguchi ABSTRACT:, Breadmaking was performed with cellulose-blended wheat flour. Cellulose granules (7 types) of various sizes (diameter) were prepared by kneading. With increase of the blend percent of the cellulose samples from 10% to 20%, breadmaking properties such as bread height and specific volume (SV) gradually decreased in every sample; however, the decreasing levels of the properties in 7 types of various sizes varied. The decrease of bread height and SV was associated with the size of the cellulose granule. It was observed at both 10% and 20% blends that the same bread height and SV as for bread baked with only wheat flour could be obtained when the diameter of cellulose granule was above 154 ,m in cellulose/wheat flour breadmaking, while they gradually decreased with granules below 154 ,m. When the largest cellulose granules were mechanically ground to make smaller ones, the bread height and SV decreased with increasing grinding time. It was ascertained that the size of the cellulose granule was important for breadmaking properties. Cellulose-blended wheat flour was subjected to mixograph tests. When cellulose granules above 154-,m dia were blended with wheat flour, the profile of the mixogram was almost the same as that for wheat flour; that is, the profile had a short mixing requirement and showed a viscous gluten matrix. However, when cellulose granules below 81-,m dia were blended, a different curve showing a nonviscous dough due to breakdown of the gluten protein was observed, as ascertained by microscopy. Farmograph test showed that the amount of the released gas from cellulose-blended bread dough increased with decrease of the size of the cellulose granule due to breakdown of the gluten protein. [source] Maturation-Dependent Alcohol Resistance in the Developing Mouse: Cerebellar Neuronal Loss and Gene Expression During Alcohol-Vulnerable and -Resistant PeriodsALCOHOLISM, Issue 8 2008Bahri Karaçay Background:, Alcohol abuse during pregnancy injures the fetal brain. One of alcohol's most important neuroteratogenic effects is neuronal loss. Rat models have shown that the cerebellum becomes less vulnerable to alcohol-induced neuronal death as it matures. We determined if maturation-dependent alcohol resistance occurs in mice and compared patterns of gene expression during the alcohol resistant and sensitive periods. Methods:, Neonatal mice received alcohol daily over postnatal day (PD) 2 to 4 or PD8 to 10. Purkinje cells and granule cells were quantified on PD25. The temporal expression patterns of 4 neuro-developmental genes and 3 neuro-protective genes in the cerebellum were determined daily over PD0 to 15 to determine how gene expression changes as the cerebellum transitions from alcohol-vulnerable to alcohol-resistant. The effect of alcohol on expression of these genes was determined when the cerebellum is alcohol sensitive (PD4) and resistant (PD10). Results:, Purkinje and granule cells were vulnerable to alcohol-induced death at PD2 to 4, but not at PD8 to 10. Acquisition of maturation-dependent alcohol resistance coincided with changes in the expression of neurodevelopmental genes. The vulnerability of cerebellar neurons to alcohol toxicity declined in parallel with decreasing levels of Math1 and Cyclin D2, markers of immature granule cells. Likewise, the rising resistance to alcohol toxicity paralleled increasing levels of GABA ,-6 and Wnt-7a, markers of mature granule neurons. Expression of growth factors and genes with survival promoting function (IGF-1, BDNF, and cyclic AMP response element binding protein) did not rise as the cerebellum transitioned from alcohol-vulnerable to alcohol-resistant. All 3 were expressed at substantial levels during the vulnerable period and were not expressed at higher levels later. Acute alcohol exposure altered the expression of neurodevelopmental genes and growth factor genes when administered either during the alcohol vulnerable period or resistant period. However, the patterns in which gene expression changed varied among the genes and depended on timing of alcohol administration. Conclusions:, Mice have a temporal window of vulnerability in the first week of life, during which cerebellar neurons are more sensitive to alcohol toxicity than during the second week. Expression of genes governing neuronal maturation changes in synchrony with the acquisition of alcohol resistance. Growth factors do not rise as the cerebellum transitions from alcohol-vulnerable to alcohol-resistant. Thus, a process intrinsic to neuronal maturation, rather than rising levels of growth factors, likely underlies maturation-dependent alcohol resistance. [source] Effects of digestible protein levels in isonitrogenous diets on growth performance and tissue composition of juvenile Atractoscion nobilisAQUACULTURE NUTRITION, Issue 1 2010E. DURAZO Abstract A study was undertaken to estimate the effects of isonitrogenous diets (ca. 604 g kg,1 crude protein) containing formaldehyde-treated (FT) fish meal and graded levels of digestible protein (DP) (541, 491, 372, 347 and 247 g kg,1) on growth performance and tissue composition of juveniles white seabass. Five diets were formulated to contain increasing levels of FT fish meal (from 0 to 384 g kg,1) and decreasing levels of non-treated fish meal (from 480 to 96 g kg,1). Each dietary treatment was fed in triplicate to apparent satiation to groups of 25 fish for 50 days. Significantly higher growth performance and feed conversion ratio were obtained in fish-fed diets containing 491 or 541 g kg,1 DP, compared with all other treatments. Apparent digestibility coefficient of protein in the diets was not significantly affected by the inclusion of treated fish meal in the diets. Estimation of protein requirements using a broken-line regression analysis indicated that maximum weight gain would be obtained with a diet containing 503 ± 23 g kg,1 DP. The results from this study suggest that a single-diet formulation using protein treated with formaldehyde as filler might be useful to estimate the requirement of DP for fish. [source] A multivariate approach to optimization of macronutrient composition in weaning diets for cod (Gadus morhua)AQUACULTURE NUTRITION, Issue 1 2006K. HAMRE Abstract Atlantic cod, initial weight 0.26 g, were fed diets varying in added protein from 530 to 830 g kg,1, lipid from 50 to 300 g kg,1 and carbohydrate from 0 to 150 g kg,1 of dry weight, according to a three-component mixture design. Analysed values of protein and lipid were 500,770 g kg,1 and 30,270 g kg,1, respectively. Analysed carbohydrate levels were as added. Increasing levels of both lipid and carbohydrate had a positive effect on fish growth (P < 10,3), whereas protein levels above 600 g kg,1 gave a reduction in growth (P < 10,4). The effects on growth were evident in fish less than 4 g, whereas fish growth between 4 and 6 g was unaffected by the dietary variation. It is hypothesized that the reduction in growth at high protein levels in fish of less than 4 g could be owing to incomplete utilization of protein, as the stomach of cod is not fully developed before the fish is approximately 1 g. Mortality and cannibalism were high in fish less than 4 g but low when the fish grew from 4 to 6 g. There was a significant decrease in cannibalism with increasing dietary lipid during the first half of the experiment (P < 0.05) and cannibalism was consistently high in fish fed less than 150 g kg,1 lipid. The lipid level in whole fish increased with increasing dietary levels of lipid (P < 10,6) and carbohydrate (P < 10,4), whereas the liver lipid level increased with increasing dietary lipid up to 200 g kg,1 (P < 10,6) and decreased thereafter (P < 10,4). Whole body glycogen increased slightly with increasing levels of dietary carbohydrate (P < 0.05) and was not affected by the other dietary variables. Liver glycogen increased in response to increasing dietary carbohydrate (P < 10,5) and decreasing levels of dietary lipid (P < 10,5). An abrupt increase in liver glycogen was seen with the reduction in dietary lipid from 100 to 50 g kg,1. The hepatosomatic index increased in response to both dietary lipid and carbohydrate (P < 10,6). It is concluded that the protein requirement of young cod is less than 500 g kg,1 of dry diet. Fish of less than 4 g should not be given more than 620 g kg,1 protein and should be supplemented with 150,200 g kg,1 lipid. Carbohydrate up to 150 g kg,1 of dry diet promoted growth and did not seem to affect the fish negatively. Fish above 4 g can be given diets varying in protein and carbohydrate over the wide range of concentrations used in the present study, but lipid supplementation should be restricted to between 100 and 200 g kg,1. [source] | |||||||||||||