Longitudinal changes of health-related quality of life over 10 years in breast cancer patients treated with radiotherapy following breast-conserving surgery

PURPOSES

The study intended to (1) assess changes of health-related quality of life (HRQoL) between early treatment-related time points and 10 years post-treatment in a cohort of breast cancer (BC) patients who received radiotherapy (RT), (2) to evaluate differences in HRQoL between long-term BC survivors and unaffected women from the same geographical region and (3) to identify determinants of long-term HRQoL in the survivor cohort.

METHODS

292 BC patients were recruited prior to RT after breast-conserving surgery between 1998 and 2001 in Germany and prospectively followed up for a median of 11.4 years (range 10.3-12.8 years). HRQoL was assessed using EORTC QLQ-C30 at pre-RT (baseline), during RT, 6 weeks after RT, and at the 10-year follow-up. Changes in mean HRQoL scores over time were assessed using linear-mixed models. HRQoL in long-term survivors and controls was compared using Wilcoxon rank-sum test, stratified by age groups. Multivariable linear regression models were used to identify determinants for HRQoL in long-term BC survivors.

RESULTS

Compared to baseline level (mean summary score of 64.9), global health status/quality of life (GHS/QoL) declined during RT (62.4) and improved 6 weeks after RT (69.9) before decreasing to baseline level at the 10-year follow-up (66.7). Most functional domains deteriorated or remained stable at 10 years post-diagnosis compared to post-RT scores, except for role functioning which improved, while dyspnea and diarrhea significantly deteriorated between those two time points. There were no significant differences in long-term GHS/QoL between BC survivors 10 years post-RT and controls for all age groups (p > 0.05). However, deficits in specific HRQoL domains such as emotional burden, sleep problems or fatigue were found to more strongly affect survivors, in particular those younger than 65 years, compared to controls. In the determinant analysis, being overweight was associated with lower GHS/QoL and physical functioning, while living with others was found to be associated with better physical functioning, and decreased dyspnea and pain levels. Certain comorbidities such as depression had a strong association with multiple HRQoL domains, including lower GHS/QoL and functioning as well as a higher level of fatigue, pain, sleep/intestinal problems, and financial difficulties. Side effects such as lymphedema/pain and fibrosis were associated with worse physical and social functioning, respectively.

CONCLUSION

The long-term GHS/QoL remained comparable when compared with the control population while restrictions in certain functional and symptoms domains in long-term BC survivors persisted over 10 years, in particular among younger survivors. Targeted screening to identify cancer survivors at risk for psychosocial/other impairment accounting also for comorbidities and treatment side effects may be warranted in long-term aftercare to address unmet health needs.

Pharmacodynamics and pharmacokinetics of insulin detemir and insulin glargine 300 U/mL in healthy dogs

Insulin glargine 300 U/mL and insulin detemir are synthetic long-acting insulin analogs associated with minimal day-to-day variability or episodes of hypoglycemia in people. Here, 8 healthy purpose-bred dogs each received 2.4 nmol/kg subcutaneous injections of insulin detemir (0.1 U/kg) and insulin glargine 300 U/mL (0.4 U/kg) on 2 different days, >1 wk apart, in random order. Blood glucose (BG) was measured every 5 min, and glucose was administered intravenously at a variable rate with the goal of maintaining BG within 10% of baseline BG ("isoglycemic clamp"). Endogenous and exogenous insulin were measured for up to 24 h after insulin injection. The effect of exogenous insulin was defined by glucose infusion rate or a decline in endogenous insulin. Isoglycemic clamps were generated in all 8 dogs after detemir but only in 4 dogs after glargine. Median time to onset of action was delayed with glargine compared to detemir (4.0 h [3.3-5.8 h] vs 0.6 h [0.6-1.2 h], P = 0.002). There was no difference in time to peak (median [range] = 6.3 h [5.0-21.3 h] vs 4.3 h [2.9-7.4 h], P = 0.15) or duration of action (16.3 h [6.1-20.1 h] vs 10.8 h [8.8-14.8 h], P = 0.21) between glargine and detemir, respectively. Glargine demonstrated a peakless time-action profile in 4/8 dogs. The total metabolic effect and peak action of detemir was significantly greater than glargine. Significant concentrations of glargine were detected in all but 1 dog following administration. Glargine might be better suited than detemir as a once-daily insulin formulation in some dogs based on its long duration of action and peakless time-action profile. Day-to-day variability in insulin action should be further assessed for both formulations.

Die rationalisierte Literaturrecherche

Versteht man die Literaturrecherche als eine gehobene Dienstleistung, für die ein echtes Bedürfnis vorliegt und der Bedarf sich ständig ausweitet, so kann letzterer von einer Organisation rational und rationell nur befriedigt werden durch teilweise Dezentralisation der Sucharbeit, durch einen hohen Grad an Arbeitsteiligkeit im eigenen Organisationsbereich, durch klare, den Arbeitsablauf regelnde Anweisungen sowie durch Anwendung technisch hochentwickelter Dokumentationsverfahren. Neben die Inhaltsanalyse des Suchauftrags, wodurch die Suchstrategie festgelegt wird, tritt die Bedarfsanalyse, wodurch Art und Umfang der nachzuweisenden Dokumente sowie die Methode des Suchverfahrens bestimmt werden. Klassische, mechanische und elektronische Recherchen bestehen gleichberechtigt nebeneinander und ergänzen sich im Einzelfalle in geeigneter Kombination. Literaturnachweis und Literaturbeschaffung können für eine rationelle Erledigung weder örtlich noch organisatorisch getrennt werden. Apparative und bibliothekarische Ausstattung der Dokumentationsstelle ist ausschließlich am Bedarf zu orientieren und diesem ständig anzupassen.

Rationalisierung der Literaturerfassung in Spezialdokumentationen

Die Erfassungsstrategie für Aufbau und aktuelle Vervollständigung einer Literaturspezialdokumentation wird am Beispiel der Spezialdokumentation der Literatur über die Wirkstoffe des pharmazeutischen „Bayer”-Sortiments entwickelt. Das sehr aufwendige Erfassungssystem von Primärliteratur kann nur durch ständige statistische Analysen der Zeitschriftenverteilung an die Wirklichkeit adaptiert und rationell gestaltet werden. Die Ergebnisse einer solchen Analyse werden mitgeteilt. Sie sind gut mit der Hypothese vereinbar, daß es für das Erscheinen von Spezialliteratur zeitschriftenspezifische Schwellen gibt, deren Logarithmen annähernd normalverteilt sind. Hierauf kann man Schätzungen über den tatsächlichen Umfang der erfaßbaren Spezialliteratur sowie über den erforderlichen Mehraufwand an Durchsicht von Primärliteratur für den Fall, daß höhere Erfassungsquoten angestrebt werden, aufbauen.

Kontingenztafelanalyse unabhängiger Daten in der Arzneimittelprüfung

Zur statistischen Analyse vierclimensionaler kategorialer Daten aus kontrollierten Arzneimittelprüfungen wird eine problemadäquate additive Zerlegung der Unabhängigkeitshypothese vorgeschlagen. Mehrfachassoziationen werden mittels der Hypothesen von Babtlett und Roy-Kastenbaum geprüft. Das Problem ihrer Übertragbarkeit auf entsprechende Randtafeln wird durch Prüfung ausschließender Hypothesen nach Ku und Kullback umgangen. Ein Anwendungsbeispiel wird gegeben.

Vergleich biologischer Wirkungen mittels programmierter Probitanalyse

Es wird ein für die IBM 7074 erstelltes, der Wertbemessung biologisch aktiver Wirkstoffe bei alternativem Effekt dienendes Programm beschrieben. Typische Anwendungsbeispiele werden geschildert. Das Modell, der Vergleich mehrerer Logdosis-Probit-Regressionsgeraden, wird in mathematisch anspruchsloser Weise besprochen, seine Annahmen werden diskutiert, seine iterativen Schätzverfahren begründet. Hinweise zur Interpretation seiner Prüfverfahren werden gegeben.

Das Programm enthält eine Reihe von Fehlerprüfungen, da es als Routineverfahren störungsfrei laufen muß. Das dokumentationsgerecht gestaltete Befundformular und die Ausgabelisten werden demonstriert.

Versuchspläne zur Testung auf Arzneimittelsicherheit vor Beginn der klinischen Prüfung

Bevor eine neu synthetisierte oder isolierte und biologisch aktive Forschungssubstanz in die klinische Prüfung gegeben wird, muß sie nach dem derzeitigen Stand der Wissenschaft auf Sicherheit getestet werden. Dies erfolgt im Probandenversuch, wobei das Prinzip der Freiwilligkeit bei voller Aufklärung gewährleistet sein muß. Die Zahl der Probanden soll möglichst klein, aber groß genug für eine verläßliche Urteilsfindung gewählt werden.

Zielvariable sind Laborgrößen und Größen der Vitalfunktionen. Da die Zahl der Zielvariablen zu der Zahl der Probanden in ein vertretbares Verhältnis gebracht werden muß, muß eine Variablenvorauswahl an Hand der Vorinformation aus pharmakologischen und toxikologischen Tierversuchen erfolgen. Eine zusätzliche Variablenreduktion wird durch Selbstversuche oder Probandenstichversuche erreicht. Hierzu müssen zusätzlich Meßwerte vor Applikation der Substanz erhoben werden, damit diese Entscheidung nicht nur auf die wenig allgemeinverbindlichen klinischen Normbereiche, sondern auch auf die individuelle Ausgangslage gegründet werden kann.

Das endgültige Urteil wird aus einem im biometrischen Sprachgebrauch »kontrollierten« Versuch gewonnen. Kontrolliert werden müssen Zeittrends, die sich aus vielerlei Gründen bei den Probanden, bei den Untersuchern und in den Labors einschleichen und die biologische Aktivität der Forschungssubstanz nach beiden Richtungen verfälschen können. Zur Gewinnung einer verläßlichen Nullinie der Wirkung ist die Einbeziehung von Placebo-Applikationen unerläßlich. Damit die Probandenzahl nied. rig gehalten werden kann, sollte der Individualvergleich dem Gruppenvergleich vorgezogen werden. Für untersucheroder laborabhängige Zielvariable müssen mehr als ein Untersucher oder ein Labor einbezogen werden.

Entsprechende Versuchspläne, die sich in der Praxis als durchführbar erwiesen und bewährt haben, werden vorgeschlagen und Hinweise zu ihrer Auswertung gegeben. Nimmt man hierbei einen möglichen Autokorrelationsfehler in Kauf, liegt man in der Deutung der Versuchsergebnisse auf der Seite der Arzneimittelsicherheit.

Detection of Strongylus vulgaris in equine faecal samples by real-time PCR and larval culture - method comparison and occurrence assessment

Background

Strongylus vulgaris has become a rare parasite in Germany during the past 50 years due to the practice of frequent prophylactic anthelmintic therapy. To date, the emerging development of resistance in Cyathostominae and Parascaris spp. to numerous equine anthelmintics has changed deworming management and the frequency of anthelmintic usage. In this regard, reliable detection of parasitic infections, especially of the highly pathogenic S. vulgaris is essential. In the current study, two diagnostic methods for the detection of infections with S. vulgaris were compared and information on the occurrence of this parasite in German horses was gained. For this purpose, faecal samples of 501 horses were screened for S. vulgaris with real-time PCR and an additional larval culture was performed in samples of 278 horses. A subset of 26 horses underwent multiple follow-up examinations with both methods in order to evaluate both the persistence of S. vulgaris infections and the reproducibility of each diagnostic method.

Results

The real-time PCR revealed S. vulgaris-DNA in ten of 501 investigated equine samples (1.9%). The larval culture demonstrated larvae of S. vulgaris in three of the 278 samples (1.1%). A direct comparison of the two methods was possible in 321 samples including 43 follow-up examinations with the result of 11 S. vulgaris-positive samples by real-time PCR and 4 S. vulgaris-positive samples by larval culture. The McNemar’s test (p-value = 0.016) revealed a significant difference and the kappa values (0.525) showed a moderate agreement between real-time PCR and larval culture.

Conclusions

The real-time PCR detected a significantly higher proportion of positives of S. vulgaris compared to larval culture and should thus be considered as a routine diagnostic method for the detection of S. vulgaris in equine samples.

What If the Rival Drives a Porsche?

Previous research found that men conspicuously consume luxury products to attract a mate and to signal their mate value. However, these studies have yet neglected to investigate the function of male conspicuous consumption in same-sex competition. Given that intersexual selection and intrasexual selection are closely related processes, it stands to reason that a further function of male conspicuous consumption could be to impress and deter same-sex rivals. An 2 (intrasexual competition context vs. control) × 2 (conspicuous luxury vs. inconspicuous nonluxury) between-subjects experimental study conducted with an Amazon Mechanical Turk sample ( N = 160) revealed that men reported both higher liking of and an intent to purchase a conspicuous luxury car compared to an inconspicuous nonluxury car due to increased feelings of social status. This effect was stronger in the intrasexual competition than in the control context. An additional perception study using a single-factor between-subjects design (conspicuous luxury vs. inconspicuous nonluxury car) among German men ( N = 405) indicated that male participants rated a man who displayed a conspicuous luxury car more as a rival and mate poacher and less as a friend. They further perceived him to be superior on various mate value characteristics (i.e., attractiveness, intelligence, ambition, and status) and rated him as more oriented toward short-term mating. In sum, our findings add to previous research in the field of evolutionary consumer psychology by suggesting that male conspicuous consumption of luxuries may also serve a function in male–male competition.

Effects of single-shot and steady-state propofol anaesthesia on rocuronium dose-response relationship: a randomised trial

BACKGROUND

Similar to volatile anaesthetics, propofol may influence neuromuscular transmission. We hypothesised that the administration of propofol influenced the potency of rocuronium depending on the duration of the administration.

METHODS

After consent, patients scheduled for elective surgery randomly received rocuronium either after induction of anaesthesia with propofol (2 min of propofol, n = 36) or after 30 min of propofol infusion (30 min of propofol, n = 36). Remifentanil was given in both groups. Neuromuscular monitoring was performed by calibrated electromyography. The dose-response relationship of rocuronium was determined with a single-bolus technique (0.07, 0.1, 0.15, 0.2, 0.3 and 0.45 mg/kg rocuronium). The primary endpoints were the ED50 and ED95 of rocuronium after 2 and 30 min propofol. Data are presented as means with (95% confidence interval). The trial is registered with the Eudra-CT: 2009-012815-16.

RESULTS

A total of 72 patients were included. Time to maximal neuromuscular blockade was significantly shorter in patients after 30 min of propofol [3.3 min (2.9-3.7)] compared with patients anaesthetised with 2 min of propofol [4.6 min (4.0-5.2)]. After 30 min of propofol, the slope of the dose-response curve was significantly steeper (30 min of propofol: 4.34 [3.62-5.05]; 2 min of propofol: [3.34 (2.72-3.96)], resulting in lower ED95 values of rocuronium (30 min of propofol: 0.287 mg/kg [0.221-0.368]; 2 min of propofol [0.391 mg/kg (0.296-0.520)]. The ED50 were not different between groups.

CONCLUSION

The potency of rocuronium was significantly enhanced after propofol infusion for 30 min. Estimates of potency those are usually determined during steady-state anaesthesia might underestimate rocuronium requirements for endotracheal intubation at the time of induction.

Pharmacological profile of 2-bromoterguride at human dopamine D2, porcine serotonin 5-hydroxytryptamine 2A, and α2C-adrenergic receptors, and its antipsychotic-like effects in rats

Dopaminergic, serotonergic, and adrenergic receptors are targets for therapeutic actions in schizophrenia. Dopamine D2 receptor partial agonists such as aripiprazole represent a treatment option for patients with this severe disorder. The ineffectiveness of terguride, another D2 receptor partial agonist, in treating schizophrenia was recently attributed to its considerably high intrinsic activity at D2 receptors. In this study, we used functional assays for recombinant D2 receptors and native 5-hydroxytryptamine 2A (5-HT2A), α2C-adrenergic, and histamine H1 receptors to compare the pharmacological properties of terguride and three of its halogenated derivatives (2-chloro-, 2-bromo-, 2-iodoterguride) with those of aripiprazole. Subsequently, we studied the antidopaminergic effects of 2-bromoterguride using amphetamine-induced locomotion (AIL). Its influence on spontaneous behavior was tested in the open field. Extrapyramidal side effect (EPS) liability was evaluated by catalepsy test. In a guanosine 5'-O-(3-[(35)S]thio)triphosphate ([(35)S]GTPγS) binding assay, 2-chloro-, 2-bromo-, and 2-iodoterguride produced intrinsic activities at human D2short (hD2S) receptors that were half as high as the intrinsic activity for terguride; aripiprazole lacked agonist activity. 2-Bromoterguride and aripiprazole activated D2S receptor-mediated inhibition of cAMP accumulation to the same extent; intrinsic activity was half as high as that of terguride. All compounds tested behaved as antagonists at human D2long/Gαo (hD2L/Gαo) receptors. Compared with aripiprazole, terguride and its derivatives displayed higher affinity at porcine 5-HT2A receptors and α2C-adrenoceptors and lower affinity at H1 receptors. 2-Bromoterguride inhibited AIL and did not induce catalepsy in rats. Because of its in vitro and in vivo properties, 2-bromoterguride may be a strong candidate for the treatment of schizophrenia with a lower risk to induce EPS.

Exaggerated aggression and decreased anxiety in mice deficient in brain serotonin

Serotonin is a major neurotransmitter in the central nervous system (CNS). Dysregulation of serotonin transmission in the CNS is reported to be related to different psychiatric disorders in humans including depression, impulsive aggression and anxiety disorders. The most frequently prescribed antidepressants and anxiolytics target the serotonergic system. However, these drugs are not effective in 20-30% of cases. The causes of this failure as well as the molecular mechanisms involved in the origin of psychological disorders are poorly understood. Biosynthesis of serotonin in the CNS is initiated by tryptophan hydroxylase 2 (TPH2). In this study, we used Tph2-deficient (Tph2(-/-)) mice to evaluate the impact of serotonin depletion in the brain on mouse behavior. Tph2(-/-) mice exhibited increased depression-like behavior in the forced swim test but not in the tail suspension test. In addition, they showed decreased anxiety-like behavior in three different paradigms: elevated plus maze, marble burying and novelty-suppressed feeding tests. These phenotypes were accompanied by strong aggressiveness observed in the resident-intruder paradigm. Despite carrying only one copy of the gene, heterozygous Tph2(+/-) mice showed only 10% reduction in brain serotonin, which was not sufficient to modulate behavior in the tested paradigms. Our findings provide unequivocal evidence on the pivotal role of central serotonin in anxiety and aggression.

Myths and facts in neuromuscular pharmacology. New developments in reversing neuromuscular blockade

Pharmacologic reversal of neuromuscular blockade is a topic not very well acknowledged and controversially discussed. Reasons for this are numerous and include missing perception of the potential complications of residual neuromuscular paralysis including an increased morbidity and mortality, as well as low efficacy and numerous unwanted side effects of the available antagonists. Duration of action of muscle relaxants cannot be pharmacologically predicted. Objective neuromuscular monitoring is the only way to detect residual paralysis. This review article would like to discuss in its first part some of the myths which revolve around the use of muscle relaxants, then highlight the problems regarding the use of acetylcholine esterase inhibitors and, in the third part, discuss the steroidal muscle relaxant encapsulator sugammadex.

[Emergency medication during pregnancy]

Medical emergencies in pregnant patients pose a great challenge. Due to a lack of experience many emergency care providers are uncertain about which drugs can be used and the dosage. The following article reviews the physiological changes during pregnancy, general considerations about pharmacotherapy in pregnant patients and highlights typical emergency scenarios with the corresponding recommendations for which drugs to use in pregnant patients.

Stimulus-dependent changes of extracellular glucose in the rat hippocampus determined by in vivo microdialysis

Neuronal activity is tightly coupled with brain energy metabolism; and glucose is an important energy substrate for neurons. The present in vivo microdialysis study was aimed at investigating changes in extracellular glucose concentrations in the rat ventral hippocampus due to exposure to the elevated plus maze. Determination of basal hippocampal glucose and lactate/pyruvate ratio in male Wistar rats was conducted in the home cage using in vivo microdialysis. Rats were exposed to the elevated plus maze, a rodent model of anxiety-related behaviour, or to unspecific stress induced by white noise (95dB) as a control condition. Basal hippocampal levels of glucose, as determined by zero-net-flux, and the basal lactate/pyruvate ratio were 1.49+/-0.05mmol/l and 13.8+/-1.1, respectively. In rats without manipulation, glucose levels remained constant throughout the experiment (120min). By contrast, exposure to the elevated plus maze led to a temporary decline in hippocampal glucose (-33.2+/-4.4%) which returned to baseline level in the home cage. White noise caused only a non-significant decrease in extracellular glucose level (-9.3+/-3.5%). In all groups, the lactate/pyruvate ratio remained unchanged by the experimental procedures. Our microdialysis study demonstrates that exposure to the elevated plus maze induces a transient decrease in extracellular hippocampal glucose concentration. In contrast, an unspecific stimulus did not change hippocampal glucose. The latter suggests that only specific behavioural stimuli increase hippocampal glucose utilization in the ventral hippocampus.

Muscle relaxant use for tracheal intubation in pediatric anaesthesia: a survey of clinical practice in Germany

OBJECTIVES

Aim of this Germany-wide study was to evaluate the use and application customs of neuromuscular blocking drugs (NMBDs) for tracheal intubation in children of age 5 years or younger.

MATERIAL AND METHODS

In the year 2005, a total of 3260 questionnaires were sent out to all heads of anesthesia departments at all types of hospitals as well as ambulatory anesthesia centers in Germany. The fields covered by the questionnaire were regarding institutional size, amount of general anesthesia and specifically pediatric cases, number of intubations and NMBDs used, frequency of use of the individual relaxants and techniques utilized when administering muscle relaxants.

RESULTS

Of the sent-out questionnaires 66.9% could be analyzed: 82% of hospitals use 1-3 muscle relaxants in children; 91% of the ambulatory anesthesia centers use a repertoire of 1-2 neuromuscular blockers for pediatric cases. However, general anesthesia with tracheal intubation in children is often induced without using any NMBD at all. Mivacurium is the predominantly used NMBD for pediatric intubation in Germany. In contrast, the use of succinylcholine is far less in ambulatory anesthesia centers than in hospitals. Despite controversial discussion, precurarization, priming, and timing are still utilized in German anesthesia practice.

CONCLUSION

In Germany, mivacurium, with its favorable pharmacologic profile for short cases, is the predominantly used NMBD for pediatric tracheal intubation. Despite the known adverse effects of intubation without muscle relaxation, this technique is also wide-spread, especially among German anesthetists in ambulatory anesthesia centers. Surveys like these are important to determine a status quo of use and application customs of NMBDs in pediatric anesthesia and provide a basis for numerous other studies.

Repeated anaesthesia with isoflurane and xylazine/levomethadone/fenpipramide premedication in female Beagle dogs: Influence on general health and wellbeing

Summary

Beagle dogs continue to be used in experimental studies and preclinical and clinical trials, many of which address the usage of anaesthesia. In order to reduce the number of animals, researchers tend to conduct several experiments on a single animal. The question arises, however, as to whether or not this frequent usage involves more than simply additional stress and discomfort for the individual animal. Within the framework of an existing study involving six female Beagle dogs, we investigated the effects of repeated (5) isoflurane anaesthesia with xylazine/levomethadone/fenpipramide premedication carried out at short intervals (2 weeks) and compared these with the effects of two treatments intermitted by a longer resting period (8 weeks). To verify our hypothesis that frequent anaesthesia affects the dog's wellbeing more than the occasional anaesthesia, the following parameters were measured at regular intervals: body weight, body temperature, respiratory rate, blood pressure, reflexes and heart rate, both at rest and during a treadmill exercise. In addition, recovery behaviour subsequent to anaesthesia was monitored for one hour. Our observations indicate that the anaesthetic effects are most prominent 24 h after the anaesthetic treatment. However, crossover analysis of our data cannot show that there is no statistical difference of whether dogs were anaesthetized occasionally or frequently. In our study, it appears that frequent anaesthesia within a two-week period did not affect the wellbeing and general health of Beagle dogs in a super-additive manner and that a minimum of two-week testing-free period is sufficient to ensure complete recovery from the unwanted effects induced by anaesthesia.

Changes in the brain serotonin satiety system in transgenic rats lacking brain angiotensinogen

In transgenic rats, TGR(ASrAOGEN)680, with reduced glial expression of angiotensinogen, changes in brain angiotensinogen are associated with reductions in serotonin (5-HT) content and/or 5-HT metabolism as determined in various brain regions, including the hypothalamus. These rats showed an anxious phenotype upon a first behavioural screen. The present study aimed to extend the search for functional consequences of changes in brain 5-HT with respect to feeding behaviour in these transgenic rats. In feeding experiments, rats were treated with the anorectic drug fenfluramine to probe for functional changes in the serotonergic satiety system. Fenfluramine (0.3 mg/kg, i.p.) reduced food intake in TGR(ASrAOGEN)680 rats whereas the minimal effective dose in wild-type rats was 3 mg/kg, i.p. Although, in the cortex, no differences were apparent in the expression of serotonin 5-HT(1A), 5-HT(1B), 5-HT(2C) receptor and 5-HT transporter mRNAs between TGR(ASrAOGEN)680 and wild-type rats, the expression of mRNAs for the 5-HT(2C) receptor and 5-HT transporter mRNA were significantly higher in the hypothalamus of TGR(ASrAOGEN)680 rats compared to wild-type rats. No differences were found in the mRNA levels for hypothalamic 5-HT(1A) and 5-HT(1B) receptors between TGR(ASrAOGEN)680 and wild-type rats. Taken together, these findings suggest that the transgenic effect on the brain 5-HT system is paralleled by functional changes of the serotonergic feeding system.

Changes in extracellular hypothalamic glucose in relation to feeding

The aim of the present in vivo microdialysis study was to investigate the relation between feeding and changes in glucose concentrations in the rat ventromedial hypothalamus (VMH). Absolute ambient glucose concentrations in VMH were 1.43 mm in non-deprived rats as compared to 0.94 mm after 24-h food deprivation. To examine whether feeding influences hypothalamic glucose, changes of glucose concentration over time were determined relative to a baseline. Experiments were conducted in relation to both, nutritional state (food-deprived rats vs. non-deprived rats) and feeding conditions throughout the experiment (freely feeding rats vs. rats without access to food). The results of this microdialysis study show clearly that glucose concentration in the VMH of rats increases significantly in relation to food intake. The data demonstrate that a 24-h food deprivation before the experiment further augments this increase (up to 350% from baseline) as compared to non-deprived conditions (up to 60% from baseline). However, the magnitude of food related increase in VMH glucose does not correlate with the individual amount of food eaten. In conclusion, the present study shows for the first time that VMH glucose concentrations increase with food intake in the early dark phase, indicating that such changes do not only occur after pharmacological treatment, but also under physiological feeding conditions. The results further indicate that the feeding related increase in VMH glucose depends on the nutritional state of the organism.

Muskelrelaxanzien in Deutschland 2005

Aim of this study was to evaluate application customs of muscles relaxants in hospitals compared to their use in private practice. Of the 3,260 questionnaires sent-out, 66.9% could be analyzed. Of these 54% were from anesthetists in private practice, 41% from heads of hospital anesthesia departments and 5% from heads of level one hospital anesthesia departments. The first difference between private practices and hospitals was the number of available muscle relaxants: 87% of private practices use 1-3 relaxants, whereas 79% of hospitals use 3-5. Another apparent difference was the relationship between general anesthesia and the number of intubations: 60% of private practices have over 80% of general anesthesia cases, but only 50% of these patients are intubated. On the contrary, two thirds of the hospitals have 50-80% general anesthesia cases and 60-70% of patients are intubated. The main wish for an ideal muscle relaxant was independent of private practice or hospital, short onset time, followed by fast recovery. In accordance 74% of anesthetists in hospitals and 72% of anesthetists in private practice voiced the wish for a non-depolarizing succinylcholine substitute. The results of this nationwide survey suggest that time pressure in combination with an increased specialization of anesthetists in private practice are the main factors for availability and use of muscle relaxants in routine anesthesia.

Effects of 8-OH-DPAT on hippocampal NADH fluorescence in vivo in anaesthetized rats

Systemic administration of the 5-HT1A receptor agonist 8-OH-DPAT modifies 5-HT neuronal transmission via stimulation of presynaptic and postsynaptic receptors. Compared to the effects of presynaptic receptor stimulation, there are less data on the effects of postsynaptic 5-HT1A receptors and the net effects of a stimulation of pre- and postsynaptic 5-HT1A receptors available. We measured the neuronal activity in the rat hippocampus after systemic treatment with 8-OH-DPAT in doses (30-300 microg/kg) known to reduce 5-HT release and anxiety-like behavior in rodents. Neuronal activity was assessed by laser-induced fluorescence spectroscopy determining changes in nicotinamide adenine dinucleotide (NADH) fluorescence in the ventral hippocampus of anaesthetized rats in vivo. NADH, a co-substrate for energy transfer in the respiratory chain, mirrors mitochondrial activity. Increased NADH fluorescence signals lower consumption of NADH caused by neuronal inhibition. 8-OH-DPAT in a dose of 300 microg/kg, but not 100 microg/kg and 30 microg/kg, increased NADH fluorescence by maximal +27 +/- 3.5%, suggesting a decreased neuronal activity in the ventral hippocampus. The selective 5-HT1A antagonist WAY-100635 (3 mg/kg) prevented the increased NADH fluorescence after 8-OH-DPAT, but had no own effect. The results show that systemic administration of the 5-HT1A agonist 8-OH-DPAT dose-dependently affects neuronal activity in the ventral hippocampus. The dose of 300 microg/kg seemingly activates presynaptic and postsynaptic receptors with dominating inhibitory postsynaptic effects.

Clomipramine and selegiline: do they influence impulse control?

Anxiety disorders in dogs are often accompanied by loss of impulse control and can result in inappropriate behaviour such as destructiveness, excessive barking and aggression. The reduction of these undesirable actions is the focus of behaviour therapy. Clomipramine and selegiline have been approved for the treatment of separation anxiety in dogs, but there are anecdotal reports that they produce inconsistent therapeutic effect. Hence, the aim of this study was to verify the efficacy of clomipramine and selegiline for regulating impulse control by using a rat model based on the delay of reward procedure. The principle is that the animal has to decide between an immediate small food reward, normally preferred by impulsive animals, and a delayed large food reward. In this study, acute effects of clomipramine (0.3-10.0 mg/kg), selegiline (0.3-3.0 mg/kg), and diazepam (1.0-3.0 mg/kg) on the impulsive behaviour of two breeding lines of rats with different anxiety-related behaviour were investigated. Neither clomipramine nor selegiline had an effect on impulse control in either breeding line. However, motor activity was decreased by clomipramine and increased by selegiline. Diazepam led to an increase in impulsive behaviour of one rat line concomitant with an increase in motor activity. The results of this rat model for studying impulsive behaviour suggest that a single administration of selegiline and clomipramine has no influence on impulsive behaviour.

Anxiety but not arousal increases 5-hydroxytryptamine release in the rat ventral hippocampus in vivo

Central serotonin [5-hydroxytryptamine (5-HT)] is involved in the aetiology of numerous disease states, including depression and anxiety disorders. Studies have shown that exposure of rats to animal tests of anxiety increases extracellular 5-HT in the cortex or hippocampus determined by in vivo microdialysis. To discriminate whether this increase is caused by the aversive conditions of an animal test for anxiety or by an unconditioned stressor evoking mainly arousal, the present study investigates the effects of an unconditioned acoustic stimulus and exposure to the elevated plus maze (X-maze), respectively, on the release of 5-HT in the ventral hippocampus compared with hippocampal 5-HT release in the home cage and in a non-aversive unfamiliar environment in freely moving rats. Our results showed a distinct pattern of 5-HT release in the ventral hippocampus depending on the stimulus used. Exposure to the X-maze for 20 min was accompanied by an 'anxious' behaviour in the rats and increased extracellular 5-HT to 165% of basal release, whereas exposure to a less aversive 'deactivated' plus maze (115+/-6%) or to white noise for 20 min in the familiar surroundings of the home cage (98+/-6%) did not change hippocampal 5-HT release significantly, despite similar behavioural activation indicated by increased locomotor activity. While both the X-maze and white noise may model anxiety and stress to a certain extent, it seems that the X-maze is more aversive. The results suggest a close relationship between anxiety-related behaviour, but not arousal/non-specific behavioural activation, and 5-HT release in the ventral hippocampus.

Transient overexpression of the 5-HT1A receptor impairs water-maze but not hole-board performance

Previously, we showed that mice that overexpress the 5-HT(1A) receptor transiently from embryonic to perinatal stages show reduced anxiety and changes in brain serotonin turnover as adults. Here, we investigated the long-term effects of the temporary overexpression of the 5-HT(1A) receptor during early embryonic and perinatal development on the performance in two memory tasks. In the hole-board test mice that were homozygous for the transgene showed similar behavioral habituation but increased locomotion compared to heterozygous mice. In contrast water-maze performance of homozygous mice was impaired compared to heterozygous mice. These results suggest that a transient overexpression of 5-HT(1A) receptor during embryonic and perinatal development has detrimental effects on water-maze performance at adult stages.

Effect of 5-HT1A receptor activation on hypothalamic glucose

The somatodendritic 5-HT1A agonist 8-OH-DPAT reduces serotonergic activity and stimulates feeding in freely feeding rats. Interactions between circulating glucose and 5-HT1A receptor expression related to feeding have been described. The aim of the present microdialysis study was to (1) describe the relation between feeding and glucose in the LH, (2) to investigate if peripherally administered 8-OH-DPAT itself has an effect on extracellular glucose in the lateral hypothalamus (LH) of conscious rats. Baseline glucose concentrations were significantly different in microdialysis samples obtained from food deprived rats compared to freely feeding rats. After re-feeding, a significant rise in glucose levels by 45% was observed in the formerly food deprived rats. In freely feeding rats, 8-OH-DPAT (0.3 mg/kg, i.p.) reduced glucose level in the LH significantly. The effect of 8-OH-DPAT on brain glucose was antagonized by pre-treatment with the 5-HT1A antagonist WAY 100635 (3 mg/kg i.p.) which had no effect on its own. The data indicate, therefore, that the effect of 8-OH-DPAT on hypothalamic glucose is mediated by 5-HT1A receptors. In contrast, the same dose of 8-OH-DPAT proven effective in the brain had no effect on peripheral glucose. Only a very high dose of the 5-HT1A agonist (1.8 mg/kg i.p.) had a hyperglycaemic effect in the periphery. In conclusion, the present results show for the first time, that glucose in the lateral hypothalamus increases with a meal. The data demonstrate furthermore 8-OH-DPAT-induced changes of hypothalamic glucose level, implicating 5-HT1A receptors being involved not only in the control of hypothalamic 5-HT as shown before, but also in the control of hypothalamic glucose.

Nucleus accumbens serotonin1A receptors control cocaine-induced hyperactivity but not local serotonin increase: an in vivo microdialysis study

The nucleus accumbens (Nac) is an important structure for cocaine-induced hyperactivity and receives a dense serotonergic (5-HT) innervation. Previous studies showed that a systemic activation of 5-HT(1A) receptors potentiates cocaine-induced hyperlocomotion, but attenuates the cocaine-induced 5-HT increase in the Nac. In order to address the role of Nac 5-HT(1A) receptors in the control of cocaine-induced and spontaneous behavioural activity and local 5-HT release, we used in vivo microdialysis in freely moving rats. The 5-HT(1A)-receptor agonist, 8-OH-DPAT (0, 1 and 10 microM), was applied locally into the Nac by reverse dialysis followed by a cocaine (10 mg/kg) or saline i.p. injection. The Nac 5-HT(1A)-receptor activation potentiated cocaine-induced hyperlocomotion, but attenuated rearing behaviour dose-dependently. Parallel to that, the cocaine-induced increase in Nac 5-HT dialysate level was unaffected, as were the decreases in 5-HIAA and DOPAC dialysate levels after cocaine. In saline treated rats, the local application of 8-OH-DPAT into the Nac affected neither spontaneous behavioural activity nor 5-HT, 5-HIAA or DOPAC dialysate levels in the Nac. These data suggest that Nac 5-HT(1A) receptors exert a bi-directional control of cocaine-induced hyperactivity, while not affecting spontaneous behaviour. Furthermore, accumbal 5-HT(1A) receptors do not appear to be directly involved in the acute effects of cocaine on 5-HT, 5-HIAA or DOPAC levels in the Nac.

NMDA-receptor antagonism via dextromethorphan and ifenprodil modulates graded anxiety test performance of C57BL/6 mice

The majority of N-methyl-D-aspartate receptors (NMDA-R) in the adult forebrain are di- or triheteromers composed of NR1, NR2A and NR2B subunits. Subunit non-selective NMDA-R antagonists produce anxiolytic-like effects together with motor and sensory side-effects. The graded anxiety test (GAT), permits the within-task distinction of drug effects on anxiety from those on activity and perception. By testing NMDA-R subunit selective agents in the GAT it might be possible to determine whether their effects on anxiety, activity and perception are interrelated, and whether separate NMDA-R subtypes are involved. Dextromethorphan (weakly NR2A-selective) (10 and 30 mg/kg, i.p.) and ifenprodil (highly NR2B-selective) (1, 3 and 5 mg/kg, i.p.) were tested in the GAT. Both drugs failed to induce anxiolysis devoid of side-effects. However, the 10 mg/kg dose of dextromethorpan showed an anxiolytic, whereas the 30 mg/kg dose showed an anxiogenic, behavioral profile. Since the selective blockade of the NR2B subunit by ifenprodil had no clear anxiolytic effect, the anxiolytic potential of NMDA subunit non-selective agents might involve NR2A-containing receptors.

Effects of xenon on mesenteric blood flow

BACKGROUND AND OBJECTIVE

The effects of xenon on mesenteric vascular resistance have not been investigated. Because human beings anaesthetized with xenon show good cardiovascular stability, we believed that the agent would have little or no effect on vascular resistance in the splanchnic bed. We determined the effects of different inhaled xenon concentrations on mesenteric blood flow and mesenteric oxygen consumption in pigs sedated with intravenous propofol.

METHODS

Twenty-three minipigs were instrumented with transit time flow probes around the pulmonary and superior mesenteric arteries as well as with pulmonary artery and portal venous catheters. A 14 h recovery was allowed followed by recordings of baseline values. Xenon was then randomly administered in 0.30, 0.50, and 0.70 end-tidal fractions.

RESULTS

The administration of xenon resulted in an 8% (not dose dependent) decrease in mean arterial pressure (from 99 +/- 15 to 91 +/- 19 mmHg; P < 0.05), a 20% decrease in calculated systemic oxygen consumption (from 0.23 +/- 0.07 to 0.19 +/- 0.04L min(-1); P < 0.01), a 20% reduction in mesenteric oxygen delivery (from 41 +/- 12 to 33 +/- 11 mL min; P < 0.001), a 37% reduction in mesentericmetabolic rate of oxygen (from 11.3 +/- 3.6 to 7.1 +/- 3.2 mL min(-1); P < 0.01) and an 8% decrease in mesenteric artery blood flow (0.22 +/- 0.07 to 0.20 +/- 0.07 L min(-1); P < 0.05) in a dose-dependent fashion. Heart rate, cardiac output, systemic vascular resistance, mesenteric vascular resistance, mesenteric oxygen extraction fraction and portal lactate concentration were not significantly altered by xenon.

CONCLUSIONS

Xenon inhalation in the propofol-sedated pig had no measurable effects on mesenteric vascular resistance. This finding may partly explain the well-known cardiovascular stability observed in patients anaesthetized with xenon. Although mesenteric artery blood flow and mesenteric oxygen delivery decreased during xenon administration, unchanged mesenteric oxygen extraction fraction and portal lactate suggest that metabolic regulation of the splanchnic circulation remained unaltered.

Strategies for the analysis of coal by laser ablation inductively coupled plasma mass spectroscopy

The potential of laser ablation inductively coupled mass spectrometry (LA-ICP-MS) was investigated for the inorganic characterization of different coal samples pressed into pellets. Reference analysis was performed by microwave-assisted digestion of the ground samples followed by ICP-MS analysis of the resulting solutions. Two different laser ablation sampling procedures were compared. For continuous sampling, three sites of the pellet were sampled for approximately one minute, whereas for sequential sampling 15 sites were sampled for two seconds, respectively. The qualitative results of the two procedures were equivalent, but continuous sampling allowed faster analysis and better precision (RSD about 10%) than sequential sampling (RSD 10-20%). Different normalization procedures with internal and extrinsic standards were investigated and allowed a quantitative determination of Al, Ti, Zn, Ni, and V with measurement uncertainties below 10% and Fe, Si, and Sn with measurement uncertainties below 20%.