Pain begets pain. When marathon runners are not in pain anymore, they underestimate their memory of marathon pain--A mediation analysis.

BACKGROUND: A previous study has shown that memory of pain induced by running a marathon might be underestimated. However, little is known about the factors that might influence such a memory distortion during pain recall. The aim of the study was to investigate the memory of pain induced by running a marathon and the factors that might influence it: (1) present pain during recall and (2) recall delay. METHODS: A total of 127 marathon runners participated in the study, which comprised of two phases. After completion of the marathon, participants were asked to rate the intensity and the unpleasantness of their pain. Either a week or a month later, they were asked again to rate the intensity and the unpleasantness of the remembered and present pain experience. RESULTS: Participants underestimated remembered pain intensity and pain unpleasantness only if they did not experience pain during recall (p < 0.05). We observed a trend for underestimation after a week (p = 0.09) and significant effect after a month (p < 0.05) of recall delay. Furthermore, present pain intensity during recall significantly mediated the memory of pain intensity induced by running the marathon, but only after a month. Similarly, present pain unpleasantness during recall significantly mediated the memory of pain unpleasantness, but only after a month. CONCLUSIONS: It is concluded that memory of pain induced by running the marathon is underestimated after a month of recall delay and mediated by present pain during recall. SIGNIFICANCE: This study explores factors acting during recall, influencing memory of naturally occurring pain induced by physical effort. The empirical findings provide the first robust evidence for a causal relationship between memory of pain and present pain during recall.

Interferometry with Bose-Einstein condensates in microgravity.

Atom interferometers covering macroscopic domains of space-time are a spectacular manifestation of the wave nature of matter. Because of their unique coherence properties, Bose-Einstein condensates are ideal sources for an atom interferometer in extended free fall. In this Letter we report on the realization of an asymmetric Mach-Zehnder interferometer operated with a Bose-Einstein condensate in microgravity. The resulting interference pattern is similar to the one in the far field of a double slit and shows a linear scaling with the time the wave packets expand. We employ delta-kick cooling in order to enhance the signal and extend our atom interferometer. Our experiments demonstrate the high potential of interferometers operated with quantum gases for probing the fundamental concepts of quantum mechanics and general relativity.

Bose-Einstein condensation in microgravity.

Albert Einstein's insight that it is impossible to distinguish a local experiment in a "freely falling elevator" from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions of atoms lose their identity and can be described by a single macroscopic wave function. We combine these two topics and report the preparation and observation of a Bose-Einstein condensate during free fall in a 146-meter-tall evacuated drop tower. During the expansion over 1 second, the atoms form a giant coherent matter wave that is delocalized on a millimeter scale, which represents a promising source for matter-wave interferometry to test the universality of free fall with quantum matter.

Daily pattern of breathing in healthy young men.

Daily changes in the pulmonary function indices were examined in 30 healthy young men. The breathing pattern technique (Lungtest system, MES, Cracow) was used to measure daily changes in basic ventilatory parameters every 3 hours during a 24-hour period. The results revealed significant daily variables in VT (tidal volume), MV (minute ventilation), VT/TI (mean inspiratory flow), and the ratios of MV/P0. 1, (minute ventilation/mouth occlusion pressure) and P0.1/VT/TI. There was lack of significant variations in the other variables. The daily minima in the variables occurred during the usual sleep period at 2:00, 5:00 and also at 8:00 hours. The results of this study demonstrate that healthy adults have small, but significant, daily variations in some of the breathing parameters, although, overall, the breathing pattern remains relatively stable around the clock.

Low amplitude daily changes in reflex ventilatory response to progressive isocapnic hypoxia.

Daily changes in reflex ventilatory responses to hypoxia were studied in 56 young healthy men participated. A rebreathing technique--progressive isocapnic hypoxia--was used to measure hypoxic chemoreflex reactivity. The measurements were repeated every 3 hours during a 24-hour period. The ventilatory response to hypoxia--analyzed as the relationships (slope) MV/SaO2 (minute ventilation/arterial oxygen blood saturation) and P0.1/SaO2 (mouth occlusion pressure/oxygen arterial blood saturation) remained relatively stable throughout the examined period exhibiting low-amplitude differences from one another with the maximum variation at 12:00 hours.

Effects of training on the ventilatory response to hypoxia.

The purpose of the present study was to examine the influence of systematical training on the ventilatory response to hypoxia. A rebreathing technique - progressive isocapnic hypoxia - was used to measure hypoxic chemoreflex reactivity. The ventilatory response was measured in a group of 22 world class adult kayakers (22.6 +/-1.9 yr), 16 young kayakers (17.8 +/-1.1 yr), and 38 control subjects (21.9 +/-1.9 yr). The ventilatory response to hypoxia - analyzed as the relationship (slope) MV/SaO(2) (minute ventilation/oxygen arterial blood saturation) - in the adult kayakers was significantly lower (-1.03 +/-0.28 L/min/%, P<0.01) compared with those in the control group (-1.81 +/-0.54 L/min/%) and the young kayakers (-1.54 +/-0.6 L/min/%; the difference between the latter two was insignificant). The following values of P(0.1)/SaO(2) (mouth occlusion pressure/oxygen arterial blood saturation) relationship were found for the investigated groups: adult kayakers (-0.20 +/-0.1 cm H/(2)O/%, P<0.05), young kayakers (-0.47 +/-0.1 cm H/(2)O/%, N.S.), control group (-0.48 +/-0.18 cm H(2)O/%). Correlation between the hypoxic ventilatory response and VO(2)max was significant in both groups of kayakers. These findings indicate that tolerance for hypoxia was elevated in the group of athletes compared with the control group. Hypoxic tolerance correlates with the duration of training.

Improvement in the face/name association performance after three months of physical training in elderly women.

Several lines of evidence suggest that physical exercise not only influences the development of muscles, cardiovascular and respiratory systems, but also exerts a significant influence on the central nervous system. We examined the influence of strength and endurance training on cognitive performance in 33 healthy elderly volunteers (women, mean age 63.5 +/-4.5 yr) over a 3-month period of supervised training program. A control group consisted of 8 age-matched (mean age 66.3 +/-4.6) healthy volunteers who did not participate in any exercise training program. To evaluate the cognitive performance in our subjects we used two tests: face/name association test and Stroop test. The tests were applied shortly before and immediately after the training program. In the experimental group, a significant improvement in the association test performance, on average, from 71.6 +/-7.3% to 79.7 +/-7.2% (P<0.0001) was observed over the 3-month training period. There were no changes in the Stroop test results over the same time. Likewise, there were no changes in the control groups. Our data demonstrate that the training regime that is strictly followed over a relatively short period of time may improve the performance in associative memory tasks in elderly subjects. The study supports the notion that physical exercise influences cognitive performance and extend this notion to be valid for healthy elderly subjects.

Detection of CFTR gene mutations in patients suffering from chronic bronchitis.

BACKGROUND: The purpose of the study was to examine cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in patients suffering from chronic bronchitis. METHODS: Thirty-two patients admitted to the Department of Pulmonology, Lublin School of Medicine, Lublin, Poland between 1995 and 1996 due to chronic bronchitis were included in the study. Patients were analyzed for the eight most common mutations of the CFTR gene (DeltaF508, G542X, N1303K, 1717-1(GoA)), W1282X, G551D, R553X, and DeltaI507 by the reverse-hybridization method. RESULTS: CFTR gene mutations were found in five of 32 (16%) patients, all within the DeltaF508 region of the CFTR gene. All positive samples were obtained from patients heterozygous for the DeltaF508 mutation. The presence of the DeltaF508 mutation was considered statistically significant when our study group was compared to the study of Poland's general population (p <0.05 Fisher's exact test). CONCLUSION: Our results suggest there is an increased presence of the DeltaF508 point mutation of the CFTR gene in Polish patients suffering from chronic bronchitis.

[Left coronary artery-pulmonary artery fistula. Case report]. / Przetoka lewej tetnicy wiencowej do pnia tetnicy plucnej. Opis przypadku.

A case of a 45-year-old male with anterior descending branch of the left coronary artery fistula to the main pulmonary trunk is reported. The patient was admitted because of a retrosternal pain. ECG showed ST-elevation in leads V2-3. This was first episode of anginal symptoms. The authors suggest that the single episode of coronary pain may have been provoked by faintness (following alcohol consumption) in the mechanism of the steal syndrome or by coronary spasm. A fistula (on coronarography) was diagnosed (the coronary arteries showed no changes). The value of the shunt calculated via Flick's method was 1.1 l/min. Exercise test, 24-hour ECG recording as well as stress thallium scintigraphy did not reveal post-exertion ischemic changes. During a 17-month post hospitalization follow-up the patient reported no anginal symptoms. Because of the small shunt and asymptomatic follow-up no surgical treatment was recommended.