Exercise, training and neutrophil microbicidal activity

The concentration in human plasma of putative neutrophil-"priming" cytokines like endogenous pyrogens is known to increase significantly in response to moderate exercise (11). This is characteristic of an acute-phase response. The ability of blood neutrophils isolated from both trained and untrained human subjects (n = 11, 9) to produce microbicidal reactive oxygen species was determined using luminol-enhanced chemiluminescence both before and after one hour of aerobic exercise at 60% VO2max. Irrespective of training and stimulus concentration, exercise nearly always caused significant "priming" of the capacity of neutrophils to produce H2O2 and HOCl upon stimulation with opsonized zymosan (P less than 0.01); however, compared to their untrained counterparts, the activity of cells isolated from trained individuals was depressed about 50% at unit stimulus concentration, both before and after exercise (P less than 0.075), whilst remaining unaltered at saturating concentrations. Although neutrophil oxygenation activity is only one parameter that contributes to immunological status, regular episodes of moderate exercise may increase resistance to infection by priming the "killing capacity" of neutrophils. In contrast, prolonged periods of intensive training may lead to increased susceptibility to common infections by diminishing this activity.     

Diabetic autonomic neuropathy: Abnormal cardiovascular reactions under general anesthesia

Summary The influence of diabetic autonomic neuropathy upon the behavior of the circulatory system was investigated in 56 patients who had undergone ophthalmological surgery. A standardized test combination (variability in heart rate during deep breathing, Valsalva ratio, 3015 ratio, change in blood pressure from lying to standing, sustained handgrip test) was used to study the patients' cardiovascular reflectory reactions. The patients were then divided into the following groups: Group I, non-diabetics Group II, diabetics without autonomic neuropathy Group III, diabetics with autonomic neuropathy The anesthetic (induction by barbiturates and conduction by inhalation agents) and the surgical procedure (pars plana vitrectomy) were standardized and always identical. During anesthesia patients in group III experienced hypotensive reactions (systolic blood pressure below 90 mm Hg) significantly more often (72.2%) than patients in group I (25%). In order to achieve stability in blood pressure the patients of group III had to be given vasoactive drugs much more often (77.8%) than the patients of group I (12.5%) and those of group II (35.7%). We found a significant correlation between the degree of autonomic dysfunction and the largest drop in blood pressure under narcosis (r=–0.60,P<0.001). However, marked variability in heart rate and cardiac rhythm disorders during anesthesia were seen only in patients of groups I and II. These results prove the atypical hemodynamic behavior and especially the extreme instability in blood pressure in diabetic autonomic neuropathy under general anesthesia. Therefore we consider it to be very helpful to check the cardiovascular reflectory status of diabetics preoperatively.Abbreviations AN autonomic neuropathy - AV atrioventricular - BP blood pressure - bpm beats per minute - cm centimeter - f female - HR heart rate - m male - PD diastolic blood pressure - PS systolic blood pressure     

Aktualisierte Handlungsempfehlungen nach der S1-Leitlinie „Atemwegserkrankung – Bildgebende Diagnostik“

Monatsschrift Kinderheilkunde -     

Association of salivary-assessed oxytocin and cortisol levels with time of night and sleep stage

There have been proposals for REM to have a function of emotional memory consolidation, and also for REM sleep to be involved in the promotion of attachment behaviour. The hormones cortisol and oxytocin, respectively, may be involved in these proposed REM sleep functions. However, there are conflicting reports on whether levels of cortisol differ between sleep stages when time since sleep onset (SSO) is controlled, and virtually no literature on whether levels of oxytocin differ between sleep stages. This study thus investigated the changes in levels of oxytocin (OT) and cortisol (CT) across the night, and whether these levels differ between REM and N2 sleep when time SSO is controlled. 20 participants (10 males, 10 females, mean age?=?20.45, SD?=?2.01) were awakened 10?min into REM and N2 sleep periods in the sleep laboratory and gave saliva samples which were assayed for OT and CT. Levels of OT were relatively constant across the night, whereas CT increased significantly. REM and N2 did not differ significantly neither for OT nor for CT. The study has implications for models of sleep-dependent memory consolidation that incorporate the late sleep increase in cortisol as a functional component of memory consolidation, and also for the medical diagnostic assaying of OT during sleep.     

Competition between an avoidance response and a safety signal: Evidence for a single learning system

Two experiments examined competition between an instrumental avoidance response and a Pavlovian safety signal for association with omission of electric shock in a human fear conditioning paradigm. Self-reported shock expectancies and skin conductance responses were consistent with blocking of learning of the instrumental contingency by prior training of the Pavlovian contingency, and vice versa. The results support the idea that a common learning mechanism underlies both Pavlovian and instrumental conditioning. The expectancy data suggest that this learning mechanism is cognitive in nature, and that Pavlovian and instrumental learning involve external and internal attributions, respectively. The procedure may thus serve as a laboratory model for attributional processes involved in the acquisition of threat expectancies in anxiety and anxiety disorders.     

The variation of morphological and functional cardiac manifestation in Fabry disease: potential implications for the time course of the disease.

AIMS: The aim of this clinical cross-sectional study was to investigate the cardiac interrelation of morphological and functional abnormalities in patients with Fabry disease. METHODS AND RESULTS: Fifty-one patients (5-78 years) were compared with 25 controls (8-77 years). In all subjects, end-diastolic thickness of the left ventricle was measured by echocardiography and ultrasonic peak systolic strain rate (SR) was extracted to assess regional myocardial function. Magnetic resonance imaging was performed to assess late-enhancement for the detection of myocardial fibrosis in Fabry patients (n=39). In patients, women <20 years of age had no hypertrophy, no late-enhancement, and normal radial and longitudinal function (SR longitudinal=-1.7+/-0.5 s(-1); P=n.s. compared with controls). Ten women, >20 years of age, had no hypertrophy, no late-enhancement, normal radial and longitudinal function in the septal wall, but reduced longitudinal function in the lateral wall (SR=-1.4+/-0.5 s(-1)). All male patients without hypertrophy and no late-enhancement had normal radial function but reduced longitudinal function in both the septal and lateral walls (SR=-1.3+/-0.3 s(-1)). Patients with hypertrophy but without late-enhancement (n=13) had reduced radial and longitudinal function. Twelve patients displaying hypertrophy and late-enhancement had severely reduced radial and longitudinal function (SR=-1.1+/-0.5 s(-1)). Two of them with the worst impairment of regional function (SR=-0.8+/-0.6 s(-1)) died in the follow-up period. CONCLUSION: These results illustrate the variation of morphological changes and its functional consequences in Fabry cardiomyopathy.     

Journey of a patient with chronic thromboembolic pulmonary hypertension

Right ventricle (RV) dysfunction is a key outcome determinant and a leading cause of death for patients with chronic thromboembolic pulmonary hypertension (CTEPH). In this report, we followed the 5-year clinical journey of a patient with CTEPH. The tricuspid pressure gradient was significantly increased in the early phase of CTEPH and “normalized” at the late phase of this patient’s clinical journey, but this “normalized” gradient is not a positive treatment response but rather an ominous sign of advancing right heart failure owing to an exhaustion of RV contractile function. Thus, appropriate interpretation of the tricuspid pressure gradient change is of importance for assessing RV dysfunction and treatment outcome during follow-up in patients with CTEPH. Besides systolic pulmonary artery pressure (SPAP), other RV functional parameters such as tricuspid annular plane systolic excursion, RV fractional area change, and RV longitudinal strain, together with clinical markers, may provide additional guidance regarding functional improvement or progression in patients with CTEPH.