Partikel in der Außenluft erhöhen das Risiko für Herz-Kreislauf-Erkrankungen

Evidence accumulated during the mid-1990 s that ambient particulate air pollution aerosol particles may not only exacerbate respiratory diseases but also be a risk factor for cardiovascular disease exacerbation. The aim of the studies described here was to assess the impact of the 1985 smog episode on the risk factor profile in the randomly selected population-based sample of the MONICA survey 1984/85 (S1). During a 13-day period in January 1985 sulphur dioxide concentrations increased four times and concentrations of total suspended atmospheric particles doubled. The impact of this time period on plasma viscosity, plasma C-reactive protein concentrations, heart rate and blood pressure was investigated. Regression models were used to assess these associations adjusting for individual risk factors such as gender, age, body mass index, serum total cholesterol and HDL-cholesterol, smoking, physical activity and medication for cardiovascular diseases and for weather conditions during the survey period. An increase in plasma viscosity, C-reactive protein and heart rate was estimated during the air pollution episode. There was also an increase in blood pressure, but this appeared to be attributable to the weather conditions during the air pollution episode. All the four outcomes were associated with the sulphur dioxide concentrations and the total suspended particle concentrations during the survey. These results indicate that ambient air pollution, particularly ambient particulate air pollution may induce systemic inflammation and modulate the autonomic function of the heart. These pathomechanisms may contribute to the observed associations between ambient air pollution concentrations and cardiovascular disease exacerbation such as hospitalisation and mortality due to cardiovascular diseases.

[Obesity and osteoporosis]

Atherosclerosis is a chronic inflammatory disease associated with an elevation of inflammatory markers such as CRP -- a robust predictor of cardiovascular events. Inflammation also plays a pivotal role in the pathogenesis of osteoporosis. IL-6 proved to be the most important predictor of bone loss in the proximal femur. Adipocyte-produced inflammatory cytokines are the pathogenetic link between obesity and its metabolic consequences. The different components of the metabolic syndrome are at the same time well-established risk factors for osteoporosis. Physical training, weight loss, and a Mediterranean-style diet all have a proven cytokine-lowering effect. Contrary to muscle mass, adipose tissue if at all contributes only marginally to the preservation of bone. As a consequence, increasing lean body mass while reducing fat mass seems to be the most effective way to prevent both atherosclerosis and osteoporosis.

Objective benefit of a 1-day training course in endoscopic hemostasis using the "compactEASIE" endoscopy simulator

BACKGROUND AND STUDY AIMS

The Erlangen Active Simulator for Interventional Endoscopy (EASIE) was introduced in 1997 as a training model for interventional endoscopy. Objective evidence of the benefits of training with this model has not previously been published. As part of two long-term projects, the benefits of a 1-day training course with the "compactEASIE" simulator were evaluated.

MATERIALS AND METHODS

Fourteen American and 18 French gastroenterology fellows were enrolled. These fellows were participants in the intensive groups performing training in endoscopic hemostasis, with a total number of 28 fellows in New York and 36 in France. Gastrointestinal endoscopy faculty members in New York and France evaluated and timed the fellows in four disciplines to establish baseline skills (manual skills; injection and coagulation; Hemoclip application; and variceal ligation) with the compactEASIE simulator. The trainees were reevaluated after an intensive 1-day course (with two or three fellows and one instructor per station), also including preparation and assistance for each procedure. The assessment (overall and parts) was done by expert tutors using an ordinal scale ranging from 1 to 10 (1 = poorest, 10 = best), recording also mistakes and performance time. The compactEASIE simulator, equipped with an upper gastrointestinal organ package and an artificial blood perfusion system, was used as the training tool.

RESULTS

A highly significant improvement ( P < or = 0.001) was observed in the performance of all endoscopic techniques. A significant reduction in performance time was also observed with three of the four endoscopic techniques. Successful hemostasis was significantly improved in two out of three techniques.

CONCLUSIONS

A 1-day training course on endoscopic hemostasis using the compactEASIE simulator is capable of improving the performance of hemostasis procedures. Long-term effects of repeated training sessions are currently subject of collaborative studies in New York and France.

Differential adaptation of neurocognitive brain functions to recurrent hypoglycemia in healthy men

Antecedent hypoglycemia is known to attenuate hormonal and symptomatic responses to subsequent hypoglycemia. Whether this pertains also to hypoglycemia-induced cognitive dysfunction is controversially discussed. Neurocognitive adaptation might essentially depend on the type of function. Here, we compared the influence of recurrent hypoglycemia in 15 healthy men on counterregulatory hormones, subjective symptoms of hypoglycemia, short-term memory performance (word recall), and performance on an auditory attention task (oddball). The attention task was also used to record event-related brain potential (ERP) indicators of stimulus processing. In each subject, three consecutive hypoglycemic clamps were performed, two on day 1 and the third on day 2. Neurocognitive testing was performed during baseline and at two different hypoglycemic plateaus (2.8 and 2.5 mmol/l) during the first and last clamp. As expected, hormonal responses were significantly reduced to the last as compared to the first hypoglycemia indicating adaptation. Subjective symptoms also decreased in response to recurrent hypoglycemia. Short-term memory performance deteriorated distinctly on the first hypoglycemic clamp, but maintained the normal level on the last clamp (P=0.006). Likewise, the impairment in reaction time (P=0.022) and response accuracy (P=0.005) was distinctly smaller on the last than first hypoglycemia. In parallel, the hypoglycemia-induced decrease in P3 amplitude (P=0.019) and the increase in P3 latency (P=0.049) were diminished with recurrent hypoglycemia, indicating that late stages of controlled stimulus processing likewise adapted. In contrast, the distinct decrease in amplitudes of the N1 and P2 components of the ERP (preceding the P3) was closely comparable in response to the first and last hypoglycemia (P>0.3). Together results indicate an adaptation to recurrent hypoglycemia for signs of controlled stimulus processing presumably involving hippocampo-prefrontocortical circuitry, while earlier automatic stages of processing appear to be spared.

Rett syndrome in females with CTS hot spot deletions: A disorder profile

From a series of 107 females with Rett syndrome (RTT), we describe the long-term history of ten females with a deletion in the C-terminus of the MECP2 gene. We observed that their disorder profile is clinically recognizable with time and different from other atypical and milder RTT phenotypes. In females with hot spot deletions in the C-terminus, dystonia is present from childhood and results in a serious spine deformation in spite of preventive measures. Their adaptive behavior is surprisingly better preserved and in contrast with the typical decline in motor functioning. The delineation of disorder profiles by long-term clinical observation can teach us about genotype/phenotype relationships and eventually about the effect of epigenetic phenomena on the final phenotype.

Carotenoid-based bill colour as an indicator of immunocompetence and sperm performance in male mallards

Female mate choice is often based on exaggerated sexual traits, signals of male qualities that females cannot assess directly. Two such key qualities are male immune and/or sexual competence, whereby honesty in signalling could be maintained by physiological trade-offs. Carotenoid-based ornaments likely constitute such honest signals, as there is direct competition for (limited) carotenoids between ornament deposition and anti-oxidant support of immune or sperm functioning. Using spectrometry, we assessed the potential signalling function of the yellow, carotenoid-based colour of the bill of male mallards, a target of female mate choice. Here we demonstrate that bill reflectance varied with plasma carotenoid level, indicating antioxidant reserves. Moreover, lower relative UV reflectance during autumn pairing predicted immune responsiveness and correlated positively with sperm velocity during breeding, a trait that affects fertility. Our data provide support for current theories that females could use carotenoid-based sexual signals to detect immune vigour and fertilizing ability of prospective mates.

Daily variation in fine and ultrafine particulate air pollution and urinary concentrations of lung Clara cell protein CC16

BACKGROUND

Daily variations in ambient particulate air pollution have been associated with respiratory mortality and morbidity.

AIMS

To assess the associations between urinary concentration of lung Clara cell protein CC16, a marker for lung damage, and daily variation in fine and ultrafine particulate air pollution.

METHODS

Spot urinary samples (n = 1249) were collected biweekly for six months in subjects with coronary heart disease in Amsterdam, Netherlands (n = 37), Erfurt, Germany (n = 47), and Helsinki, Finland (n = 47). Ambient particulate air pollution was monitored at a central site in each city.

RESULTS

The mean 24 hour number concentration of ultrafine particles was 17.3x10(3) cm(-3) in Amsterdam, 21.1x10(3) cm(-3) in Erfurt, and 17.0x10(3) cm(-3) in Helsinki. The mean 24 hour PM2.5 concentrations were 20, 23, and 13 microg/m3, respectively. Daily variation in ultrafine particle levels was not associated with CC16. In contrast, CC16 concentration seemed to increase with increasing levels of PM2.5 in Helsinki, especially among subjects with lung disorders. No clear associations were observed in Amsterdam and Erfurt. In Helsinki, the CC16 concentration increased by 20.2% (95% CI 6.9 to 33.5) per 10 microg/m3 increase in PM2.5 concentration (lag 2). The respective pooled effect estimate was 2.1% (95% CI -1.3 to 5.6).

CONCLUSION

The results suggest that exposure to particulate air pollution may lead to increased epithelial barrier permeability in lungs.

Radiofrequency Ablation of Liver Tumors: How to Enlarge the Necrotic Zones?

In an attempt to increase necrotic zones in liver tissue by radiofrequency ablation fresh bovine liver was coagulated by means of a needle electrode continuously perfused with NaCl solution. Power output (60 W) and application time (15 min) were kept constant while the perfusion was varied in terms of saline concentration (0.9, 5.85 and 10%) and perfusion rate (40 or 80 ml/h). Our results showed that the use of higher osmolar saline solutions in radiofrequency ablation with perfused needle electrodes did not lead to significantly larger coagulation volumes. By contrast, increasing the perfusion rate produced significantly larger necrotic zones. Doubling the perfusion rate made it possible to reach higher temperatures (>60 degrees C) within significantly shorter time.

[Outcome sensitivity of the North American Spine Society Instrument with special consideration for the neurogenic symptoms of chronic back pain]

BACKGROUND

Back pain is one of the most common chronic diseases in developed countries. The related enormous direct and indirect costs demand evidence-based decisions on rehabilitative care. Our study is intended to evaluate the two NASS outcome dimensions pain and neurological symptoms regarding their sensitivity to change within an inpatient rehabilitation scheme for chronic back pain.

METHODS

The study observed a cohort of consecutive patients for one year (n = 70). By applying two outcomes instruments which are in common use internationally (SF-36 and NASS) it enhances comparability with other studies. Moreover the FFbH-R was applied for cross validation.

RESULTS

On discharge from hospital an improvement of physical and emotional health as well as pain reduction were found. The results of the various instruments are consistent and support each other and suggest sensitivity to change of the NASS instrument regarding its pain and neurology subdimensions.

CONCLUSION

The NASS outcome instrument monitors well the established therapeutic effects of chronic back pain inpatient rehabilitation schemes in the short run and in the long run over a twelve-month period following hospital discharge.

The selfish brain: competition for energy resources

The brain occupies a special hierarchical position in the organism. It is separated from the general circulation by the blood-brain barrier, has high energy consumption and a low energy storage capacity, uses only specific substrates, and it can record information from the peripheral organs and control them. Here we present a new paradigm for the regulation of energy supply within the organism. The brain gives priority to regulating its own adenosine triphosphate (ATP) concentration. In that postulate, the peripheral energy supply is only of secondary importance. The brain has two possibilities to ensure its energy supply: allocation or intake of nutrients. The term 'allocation' refers to the allocation of energy resources between the brain and the periphery. Neocortex and the limbic-hypothalamus-pituitary-adrenal (LHPA) system control the allocation and intake. In order to keep the energy concentrations constant, the following mechanisms are available to the brain: (1) high and low-affinity ATP-sensitive potassium channels measure the ATP concentration in neurons of the neocortex and generate a 'glutamate command' signal. This signal affects the brain ATP concentration by locally (via astrocytes) stimulating glucose uptake across the blood-brain barrier and by systemically (via the LHPA system) inhibiting glucose uptake into the muscular and adipose tissue. (2) High-affinity mineralocorticoid and low-affinity glucocorticoid receptors determine the state of balance, i.e. the setpoint, of the LHPA system. This setpoint can permanently and pathologically be displaced by extreme stress situations (chronic metabolic and psychological stress, traumatization, etc.), by starvation, exercise, infectious diseases, hormones, drugs, substances of abuse, or chemicals disrupting the endocrine system. Disorders in the 'energy on demand' process or the LHPA-system can influence the allocation of energy and in so doing alter the body mass of the organism. In summary, the presented model includes a newly discovered 'principle of balance' of how pairs of high and low-affinity receptors can originate setpoints in biological systems. In this 'Selfish Brain Theory', the neocortex and limbic system play a central role in the pathogenesis of diseases such as anorexia nervosa and obesity.

Glucocorticoids and melanocortins in the regulation of body weight in humans

The last decade witnessed a dramatic increase in knowledge concerning regulation of body weight and obesity. According to recent concepts constancy of body weight is a side product of regulatory events which ensure constant glucose fluxes to the brain. Within these control systems glucocorticoids and melanocortins play a fundamental role at several sites. The melanocortin neurons in the arcuate nucleus are important mediators of the feedback effects of leptin and insulin. Glucocorticoid and mineralocorticoid receptors in hippocampal neurons are crucial as they define the balance between glucose allocation processes and food intake. Thereby, the hippocampal structures determine the setpoint for bodyweight regulation. Novel approaches to treatment of obesity must aim at manipulating these brain structures.