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Min Delay (min + delay)
Selected AbstractsMeasurement delay associated with the Guardian® RT continuous glucose monitoring systemDIABETIC MEDICINE, Issue 1 2010C. Wei Diabet. Med. Abstract Aims, Using compartment modelling, we assessed the time delay between blood glucose and sensor glucose measured by the Guardian® RT continuous glucose monitoring system in young subjects with Type 1 diabetes (T1D). Methods, Twelve children and adolescents with T1D treated by continuous subcutaneous insulin infusion (male/female 7/5; age 13.1 ± 4.2 years; body mass index 21.9 ± 4.3 kg/m2; mean ± sd) were studied over 19 h in a Clinical Research Facility. Guardian® RT was calibrated every 6 h and sensor glucose measured every 5 min. Reference blood glucose was measured every 15 min using a YSI 2300 STAT Plus Analyser. A population compartment model of sensor glucose,blood glucose kinetics was adopted to estimate the time delay, the calibration scale and the calibration shift. Results, The population median of the time delay was 15.8 (interquartile range 15.2, 16.5) min, which was corroborated by correlation analysis between blood glucose and 15-min delayed sensor glucose. The delay has a relatively low intersubject variability, with 95% of individuals predicted to have delays between 10.4 and 24.3 min. Population medians (interquartile range) for the scale and shift are 0.800 (0.777, 0.823) (unitless) and 1.66 (1.47, 1.84) mmol/l, respectively. Conclusions, In young subjects with T1D, the total time delay associated with the Guardian® RT system was approximately 15 min. This is twice that expected on physiological grounds, suggesting a 5- to 10-min delay because of data processing. Delays above 25 min are rarely to be observed. [source] Dietary restriction inhibits spatial learning ability and hippocampal cell proliferation in rats,JAPANESE PSYCHOLOGICAL RESEARCH, Issue 1 2008SHUICHI YANAI Abstract: We investigated the effect of dietary restriction on spatial learning ability and hippocampal cell proliferation in adult rats using two spatial learning tasks and immunohistochemical staining with 5-bromo-2,-deoxyuridine (BrdU). Sixteen rats were divided into restricted or ad lib feeding groups at 70 days of age, and were trained in the delayed-matching-to-place (DMTP) task (a working memory task) from 93 days of age, and then the Morris water maze task (a reference memory task). Dietary restriction had no effect on the DMTP task with 30 s delay and on the water maze task. However, in the DMTP task with 30 min delay, restricted rats performed significantly more poorly than ad lib rats. Quantitative analysis of hippocampal cell proliferation revealed that the density of newborn cells in restricted rats was significantly lower than that in ad lib rats. These results suggest that a loss of proliferating capacity in the hippocampus may be a candidate for an anatomical and biological basis for the cognitive decline caused by dietary restriction. [source] How long do the short-term violent video game effects last?AGGRESSIVE BEHAVIOR, Issue 3 2009Christopher Barlett Abstract How long do the effects of the initial short-term increase in aggression and physiological arousal last after violent video game play? Study 1 (N=91) had participants complete pre- and postvideo game measures of aggressive thoughts, aggressive feelings, and heart rate. Then, participants completed Time 3 measures after 4,min or 9,min of delay. Study 2 employed a similar procedure, but had participants (N=91) complete the hot sauce paradigm to assess aggressive behavior after a 0, 5, or 10,min delay. First, results indicated that aggressive feelings, aggressive thoughts, aggressive behavior, and heart rate initially increased after violent video game play. Second, results of the delay condition revealed that the increase in aggressive feelings and aggressive thoughts lasted less than 4,min, whereas heart rate and aggressive behavior lasted 4,9,min. Aggr. Behav. 35:225,236, 2009. © 2009 Wiley-Liss, Inc. [source] The development of haddock and Atlantic cod sperm cryopreservation techniques and the effect of sperm age on cryopreservation successJOURNAL OF FISH BIOLOGY, Issue 2 2004R. M. Rideout Three cryoprotectants [dimethyl sulphoxide (DMSO), propylene glycol (PG) and glycerol], two diluents (sucrose- and saline-based), two sperm collection times, two freezing rates and three times between thaw and activation (0, 30 and 60 min) were tested in order to develop a protocol for the cryopreservation of sperm of haddock Melanogrammus aeglefinus and Atlantic cod Gadus morhua. The faster freezing rate resulted in extremely low post-thaw motility in comparison to the slower freezing rate, which was successful for sperm from both gadids. In both cases, the use of PG resulted in significantly higher post-thaw sperm motility-recovery indices than with DMSO or glycerol, which did not differ significantly from one another. Diluent had no effect on post-thaw sperm motility for Atlantic cod or haddock. Sperm collected at the end of the spawning season tended to have reduced post-thaw motility compared to that collected 2 weeks after the start of spawning. A 30 min delay between thaw and activation of haddock and Atlantic cod sperm resulted in a significant decrease in sperm motility. When PG was used as cryoprotectant, sperm motility continued to decrease between 30 and 60 min post-thaw. With DMSO or glycerol as cryoprotectant, motilities were already very low after 30 min post-thaw and did not decrease any further after 60 min. Cryoprotectant, diluent and time between thaw and activation had no effect on mean or maximum sperm swimming speeds for either Atlantic cod or haddock sperm. Fertilization success for haddock eggs, like sperm motility, was higher with PG-frozen sperm than DMSO- or glycerol-frozen sperm. These results constitute the first reported successful cryopreservation of haddock sperm and improve on previous methods used to cryopreserve sperm from Atlantic cod. [source] Binge Pattern Ethanol Exposure in Adolescent and Adult Rats: Differential Impact on Subsequent Responsiveness to EthanolALCOHOLISM, Issue 8 2000Aaron M. White Background: Recent evidence indicates that adolescent animals are more sensitive than adults to the disruptive effects of acute ethanol exposure on spatial learning. It is not yet known whether adolescent animals are also more sensitive than adults to the enduring neurobehavioral effects of repeated ethanol exposure. In this study, animals were exposed to ethanol in a binge-pattern during either adolescence or adulthood. At a time when all subjects were adults, spatial working memory was examined in the absence and presence of an acute ethanol challenge. Methods: Rats were exposed to ethanol (5.0 g/kg intraperitoneally) or isovolumetric saline at 48 hr intervals over 20 days. Exposure began on either postnatal day 30 (adolescent group) or 70 (adult group). Twenty days after the final injection, a time at which all animals were adults, the subjects were tested on an elevated plus maze and then were trained to perform a spatial working memory task on an eight-arm radial maze. At the beginning of each session of training on the working memory task, subjects retrieved food rewards on four of the eight arms. After a delay, subjects were placed on the maze and allowed to retrieve food from the remaining four arms. Results: Prior exposure to ethanol did not influence behavior on the plus maze. Performance of the groups did not differ during acquisition of the spatial working memory task with a 5 min delay or during subsequent testing with a 1 hr delay. However, animals treated with ethanol during adolescence exhibited larger working memory impairments during an ethanol challenge (1.5 g/kg intraperitoneally) than subjects in the other three groups. Conclusions: The findings indicate that binge pattern exposure to ethanol during adolescence enhances responsiveness to the memory-impairing effects of ethanol in adulthood. [source] Plasma membrane permeabilization by 60- and 600-ns electric pulses is determined by the absorbed doseBIOELECTROMAGNETICS, Issue 2 2009Bennett L. Ibey Abstract We explored how the effect of plasma membrane permeabilization by nanosecond-duration electric pulses (nsEP) depends on the physical characteristics of exposure. The resting membrane resistance (Rm) and membrane potential (MP) were measured in cultured GH3 and CHO cells by conventional whole-cell patch-clamp technique. Intact cells were exposed to a single nsEP (60 or 600 ns duration, 0,22 kV/cm), followed by patch-clamp measurements after a 2,3 min delay. Consistent with earlier findings, nsEP caused long-lasting Rm decrease, accompanied by the loss of MP. The threshold for these effects was about 6 kV/cm for 60 ns pulses, and about 1 kV/cm for 600 ns pulses. Further analysis established that it was neither pulse duration nor the E-field amplitude per se, but the absorbed dose that determined the magnitude of the biological effect. In other words, exposure to nsEP at either pulse duration caused equal effects if the absorbed doses were equal. The threshold absorbed dose to produce plasma membrane effects in either GH3 or CHO cells at either pulse duration was found to be at or below 10 mJ/g. Despite being determined by the dose, the nsEP effect clearly is not thermal, as the maximum heating at the threshold dose is less than 0.01 °C. The use of the absorbed dose as a universal exposure metric may help to compare and quantify nsEP sensitivity of different cell types and of cells in different physiological conditions. The absorbed dose may also prove to be a more useful metric than the incident E-field in determining safety limits for high peak, low average power EMF emissions. Bioelectromagnetics 30:92,99, 2009. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||