How have trends in lifespan variation changed since 1950? A comparative study of 17 Western European countries.

Lifespan variation adds to life expectancy by measuring the inequality surrounding age of death that a population faces. Countries that tackle premature mortality generally have decreasing lifespan variation but this is the first study to compare and statistically assess when and to what extent trends in lifespan variation have changed across Western Europe. Lifespan variation was measured using e† and joinpoint regression analysed the timing and rate of change. Trends have been mostly downward with the recent exception of men in Scotland, Northern Ireland, Ireland and Finland where trends have flattened or show slight increases. Future research aimed at identifying the ages and causes of death, driving trends in these countries, is key to preventing increasing inequalities.

How much of the difference in life expectancy between Scottish cities does deprivation explain?

BACKGROUND: Glasgow's low life expectancy and high levels of deprivation are well documented. Studies comparing Glasgow to similarly deprived cities in England suggest an excess of deaths in Glasgow that cannot be accounted for by deprivation. Within Scotland comparisons are more equivocal suggesting deprivation could explain Glasgow's excess mortality. Few studies have used life expectancy, an intuitive measure that quantifies the between-city difference in years. This study aimed to use the most up-to-date data to compare Glasgow to other Scottish cities and to (i) evaluate whether deprivation could account for lower life expectancy in Glasgow and (ii) explore whether the age distribution of mortality in Glasgow could explain its lower life expectancy. METHODS: Sex specific life expectancy was calculated for 2007-2011 for the population in Glasgow and the combined population of Aberdeen, Dundee and Edinburgh. Life expectancy was calculated for deciles of income deprivation, based on the national ranking of datazones, using the Scottish Index of Multiple Deprivation. Life expectancy in Glasgow overall, and by deprivation decile, was compared to that in Aberdeen, Dundee and Edinburgh combined, and the life expectancy difference decomposed by age using Arriaga's discrete method. RESULTS: Life expectancy for the whole Glasgow population was lower than the population of Aberdeen, Dundee and Edinburgh combined. When life expectancy was compared by national income deprivation decile, Glasgow's life expectancy was not systematically lower, and deprivation accounted for over 90 % of the difference. This was reduced to 70 % of the difference when carrying out sensitivity analysis using city-specific income deprivation deciles. In both analyses life expectancy was not systematically lower in Glasgow when stratified by deprivation. Decomposing the differences in life expectancy also showed that the age distribution of mortality was not systematically different in Glasgow after accounting for deprivation. CONCLUSIONS: Life expectancy is not systematically lower across the Glasgow population compared to Aberdeen, Dundee and Edinburgh combined, once deprivation is accounted for. This provides further evidence that tackling deprivation in Glasgow would probably reduce the health inequalities that exist between Scottish cities. The change in the amount of unexplained difference when carrying out sensitivity analysis demonstrates the difficulties in comparing socioeconomic deprivation between populations, even within the same country and when applying an established ecological measure. Although the majority of health inequality between Glasgow and other Scottish cities is explained by deprivation, the difference in the amount of unexplained inequality depending on the relative context of deprivation used demonstrates the challenges associated with attributing mortality inequalities to an independent 'place effect'.

Low dose rotenone treatment causes selective transcriptional activation of cell death related pathways in dopaminergic neurons in vivo.

Mitochondrial complex I inhibition has been implicated in the degeneration of midbrain dopaminergic (DA) neurons in Parkinson's disease. However, the mechanisms and pathways that determine the cellular fate of DA neurons downstream of the mitochondrial dysfunction have not been fully identified. We conducted cell-type specific gene array experiments with nigral DA neurons from rats treated with the complex I inhibitor, rotenone, at a dose that does not induce cell death. The genome wide screen identified transcriptional changes in multiple cell death related pathways that are indicative of a simultaneous activation of both degenerative and protective mechanisms. Quantitative PCR analyses of a subset of these genes in different neuronal populations of the basal ganglia revealed that some of the changes are specific for DA neurons, suggesting that these neurons are highly sensitive to rotenone. Our data provide insight into potentially defensive strategies of DA neurons against disease relevant insults.

Effects of acute systemic 3-nitropropionic acid administration on rat activity and acoustic startle.

Spontaneous activity, acoustic startle, and prepulse inhibition (PPI) of acoustic startle were measured in male Sprague-Dawley rats 3-5 h after 0, 10, 15, or 20 mg/kg i.p. 3-nitropropionic acid (3-NP), a mitochondrial toxin. Mean activity was significantly influenced by the 3-NP dose due to decreased activity for 20 mg/kg. Mean startle amplitude was not significantly affected by the 3-NP dose. Means of PPI for prepulses 6 and 12 dBA above background were smaller than means for respective 0 mg/kg doses, but the main effect of 3-NP dose did not reach statistical significance in ANOVA. The changes in measured exploratory-type activity and, possibly, in startle PPI parallel the occurrence of clinical signs exhibited at 3-5 h after 3-NP injection. Neural processing involved in these quantitative behavioral endpoints seems to be affected as energy stores are depleted and degenerative processes are beginning.

Effects of hypothalamic peptide hormones on the electrical activity of Aplysia neurons.

The effect of luteinizing hormone-releasing hormone (LHRH) and thyrotropin-releasing hormone (TRH) on the electrical activity of neurons in the abdominal ganglion of Aplysia californica was studied. Where tested, TRH had no effect. The neurosecretory white-cell neurons were the most responsive of the neurons tested with LHRH. Bath applications of 1 micro M LHRH increased firing rates in 4 of 5 white cells for extended periods of time. The increased rates persisted in an LHRH-deficient bath. A similar result was obtained with bath applications of the LHRH agonist analog D-Ala6, des-Gly10-LHRH-ethylamide. The iontophoresis of LHRH onto white-cell somata either produced no change in electrical activity or initiated an increase in firing rate and bursting patterns which outlasted the application period. Two types of white cells are suggested by the white-cell responsiveness to LHRH. The white cells responsive to the decapeptide are candidate model neurons for studying the membrane actions of LHRH.

Modification of acoustic and tactile startle by single microwave pulses.

Single microwave pulses at 1.25 GHz were delivered to the head and neck of male Long-Evans rats as a prestimulus to acoustic and tactile startle. For acoustic startle, pulses averaging 0.96 microsecond in duration were tested with two specific absorption rate (specific absorption) ranges, 15.0-30.0 kW/kg (16.0-44.2 mJ/kg) and 35.5-86.0 kW/kg (66.6-141.8 mJ/kg), delivered 201, 101, 51, 3, and 1 ms before and 1 ms after onset of a startling noise. The low-intensity pulse did not affect peak amplitude, integral, or latency of the whole-body startle response. The high-intensity pulse at 101 and 51 ms inhibited the startle response by decreasing peak amplitude and integral; at 201 and 51 ms latency was increased. The high-intensity pulse at 1 ms enhanced the startle response by increasing peak amplitude and at 3 ms by increasing integral. For tactile startle, either microwave pulses averaging 7.82 microseconds in duration and 55.9-113.3 kW/kg (525.0-1055.7 mJ/kg) or 94 dB SPL clicks were delivered 157, 107, 57, and 7 ms before and 43 ms after onset of a startling air burst. The microwave pulse at 57 ms inhibited the startle response by decreasing peak amplitude; at 157, 107, 57, and 7 ms it increased latency. The microwave pulse at 43 ms after onset enhanced the startle response by increasing peak amplitude. The acoustic click at 157 and 57 ms inhibited the startle response by decreasing peak amplitude; at 157,2 107, and 57 ms it increased latency.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultra-wideband electromagnetic pulses and morphine-induced changes in nociception and activity in mice.

Mice were exposed to ultra-wideband (UWB) electromagnetic pulses averaging 99-105 kV/m peak amplitude, 0.97-1.03 ns duration, and 155-174 ps rise time, after intraperitoneal administration of saline or morphine sulfate. They were then tested for thermal nociception on a 50 degrees C surface and for spontaneous locomotor activity and its time profile over 5 min. Analysis of results showed no effect of UWB exposure on nociception and activity measures in CF-1 mice after 15-, 30-, or 45-min exposure to pulses at 600/s or after 30-min exposure to UWB pulses at 60/s. Similarly, no effect was seen in C57BL/6 mice after 30-min exposure to pulses at 60/s or 600/s. Although trends in morphine-modified measures seen with UWB pulse repetition frequency could be expected because of increased levels of low-frequency energy, no significant change was seen in normal or morphine-modified nociception or activity after UWB exposure. This indicated lack of effect of the UWB pulses used in these experiments on nervous system components, including endogenous opioids, involved in these behaviors.

Frequency of micronuclei in the blood and bone marrow cells of mice exposed to ultra-wideband electromagnetic radiation.

PURPOSE: To investigate the extent of genetic damage in the peripheral blood and bone marrow cells of mice exposed to ultra-wideband electromagnetic radiation (UWBR). MATERIALS AND METHODS: CF-1 male mice were exposed to UWBR for 15 min at an estimated whole-body average specific absorption rate of 37 mW x kg(-1). Groups of untreated control and positive control mice injected with mitomycin C were also included in the study. After various treatments, half of the mice were killed at 18 h, and the other half at 24 h. Peripheral blood and bone marrow smears were examined to determine the extent of genotoxicity, as assessed by the presence of micronuclei (MN) in polychromatic erythrocytes (PCE). RESULTS: The percentages of PCE and the incidence of MN per 2000 PCE in both tissues in mice killed at 18 h were similar to the frequencies observed in mice terminated at 24 h. There were no significant differences in the percentage of PCE between control and the mice with or without UWBR exposure; the group mean values (+/- standard deviation) were in the range of 3.1+/-0.14 to 3.2+/-0.23 in peripheral blood, and 49.0+/-3.56 to 52.3+/-4.02 in bone marrow. The mean incidence of MN per 2000 PCE in control and in mice with or without UWBR exposure ranged from 7.7+/-2.00 to 9.7+/-2.54 in peripheral blood and 7.4+/-2.32 to 10.0+/-3.27 in bone marrow. Pairwise comparison of the data did not reveal statistically significant differences between the control and mice with or without UWBR exposure groups (excluding positive controls). CONCLUSION: Under the experimental conditions tested, there was no evidence for excess genotoxicity in peripheral blood or bone marrow cells of mice exposed to UWBR.

Method to record evoked potentials from the frog eighth nerve.

A method for recording evoked potentials from the eighth nerve of frogs is described. A prominent bipolar wave with latency of 3-6 ms recorded in response to auditory stimuli in Rana catesbeiana is attributable to eighth-nerve activity. The evoked potential provides an integrated response for study of inner ear and peripheral neural activity which complements responses obtained by other recording methods.

Auditory unit responses to single-pulse and twin-pulse microwave stimuli.

Responses of units in the cat cochlear nucleus to single microwave pulses with different durations and to twin microwave pulses with different interpulse delays are used to study microwave hearing. Inferred threshold specific absorption rate is less than 6 mW/g; inferred threshold specific absorption, less than 0.5 microJ/g. The existence of responses from units with characteristic frequencies (CFs) from 931 Hz to 25.5 kHz is not consistent with a primary role for head resonance in microwave hearing. Patterns of response amplitude have a periodicity of 1/CF and are fully explained by frequency content of the pulse stimulus and signal processing of the auditory system. For pulses shorter than about 0.24/CF, it is shown that response amplitude is predictably proportional to pulse energy.

Sensing platform for acoustic startle responses from rat forelimbs and hindlimbs.

A sensing platform with two piezoelectric transducers was designed and fabricated to measure acoustic startle responses from forelimbs and hindlimbs in the rat. Testing with a vibrator showed that separate forces were measured from 5 to 25 Hz with mean sensitivities of 2.395 and 2.022 V/N and mean linearity errors of 3.23 and 2.98% FS for the forelimb and hindlimb sensors, respectively. Forelimb and hindlimb response waveforms of male Sprague-Dawley rats had shapes similar to the commonly recorded wholebody response but were smaller in amplitude.

Owner experiences with home use of a gastrostomy tube in their dog or cat.

OBJECTIVE: To describe owner experiences with gastrostomy tubes used at home. DESIGN: Telephone survey. ANIMALS: 20 cats and 5 dogs. PROCEDURE: Owner's opinions obtained by phone interview. RESULTS: Although 32% (8/25) of owners were initially reluctant to feed their cat or dog through the gastrostomy tube, 92% (22/24) of owners became comfortable with the procedure. Eighty-four percent (21/25) of owners were able to feed their dog or cat unassisted; 16% (4/25) required another person to help. Median time required for feeding was 19.8 minutes. Ninety-six percent (24/25) of owners believed their dog or cat was comfortable with the procedure. Eighty-four percent (21/25) of owners experienced complications or difficulties. Most problems involved bandage maintenance, administration of food through the syringe and tube, or acquisition of syringes and special foods. Ninety-six percent (22/23) of owners would be willing to use a gastrostomy tube again. CLINICAL IMPLICATIONS: Most owners had positive experiences with the feeding experience and would be willing to use gastrostomy tube feeding again. Difficulties encountered by owners were not serious and could be avoided by specific client instruction.

Eye movements and target fixation during dragonfly prey-interception flights.

The capture of flying insects by foraging dragonflies is a highly accurate, visually guided behavior. Rather than simply aiming at the prey's position, the dragonfly aims at a point in front of the prey, so that the prey is intercepted with a relatively straight flight trajectory. To better understand the neural mechanisms underlying this behavior, we used high-speed video to quantify the head and body orientation of dragonflies (female Erythemis simplicicollis flying in an outdoor flight cage) relative to an artificial prey object before and during pursuit. The results of our frame-by-frame analysis showed that during prey pursuit, the dragonfly adjusts its head orientation to maintain the image of the prey centered on the "crosshairs" formed by the visual midline and the dorsal fovea, a high acuity streak that crosses midline at right angles about 60 degrees above the horizon. The visual response latencies to drifting of the prey image are remarkably short, ca. 25 ms for the head and 30 ms for the wing responses. Our results imply that the control of the prey-interception flight must include a neural pathway that takes head position into account.

Slow and rapid responses to CW and pulsed microwave radiation by individual Aplysia pacemakers.

Specific absorption rates (SARs) of microwave energy that altered firing rates were determined for individual pacemaker neurons in the abdominal ganglion of Aplysia californica. A stripline apparatus provided both for artifact-free recording of transmembrane potentials and for precise determination of the rate of absorption of microwave energy. Exposure for two to three minutes at an SAR of only a few mW/g was capable of changing the firing rate of some pacemakers. Two types of responses were observed. The response that was seen in all neurons developed slowly, reaching a steady state in one to three minutes. The other response was seen in a few neurons and occurred within five seconds from the onset of irradiation. Similar responses were obtained for two microwave frequencies, 1.5 and 2.45 GHz. Pulsed radiation induced rapid changes of firing rate more readily than did CW radiation at the same SAR. A convective heating scheme was used to study the effects of temperature changes on the pacemakers' firing rates. Since all of the responses are not readily explained by general heating of the preparation, alternate mechanisms are suggested for the observed effects.