Adherence to the Swiss guidelines for management of COPD: experience of a Swiss teaching hospital

QUESTIONS UNDER STUDY

Swiss guidelines for the management of chronic obstructive pulmonary disease (COPD) were published in 2002. We aimed at assessing adherence to the proposed guidelines by the physicians in charge for all patients referred to our hospital for acute exacerbations of COPD over a one year period.

METHODS

In a prospective observational study, data from a questionnaire and from records of all patients referred to our hospital with acute exacerbation of COPD were collected. Diagnostic steps as well as therapeutic and prophylactic interventions were reviewed. Where applicable, interventions were stratified according to proposed levels of evidence A-D.

RESULTS

45 patients in whom the diagnosis of COPD had been made before were included. Diagnosis was established by spirometry in 71%, in the remaining diagnosis was based on clinical grounds only. Non-smoking advice was given to 69%, and 16% were offered a nicotine-replacement trial (level A). Information about a disease management plan was given in 40% of the patients (level B), 22% had done a six minute walking distance test. 27% of the patients had participated in a pulmonary rehabilitation program (level A). 93% were on regular bronchodilator therapy (level B), and 56% had regular inhaled corticosteroids (level B).

CONCLUSION

Confirmation of the diagnosis of COPD by spirometry is lacking in a significant number of patients. Most patients were treated with regular bronchodilators, however, relevant over-treatment with beta-adrenergic substances and overuse of inhaled corticosteroids in mild disease stages are common. Efforts for disease prevention and education as well as awareness of the potential benefits of pulmonary rehabilitation programs are still insufficient. Efforts to improve the adherence to the Swiss guidelines for the management of COPD should be intensified.

Efavirenz Intoxication Due to Slow Hepatic Metabolism

We describe a human immunodeficiency virus-positive woman who presented with severe psychosis while she was receiving therapy with efavirenz. Her plasma efavirenz level was excessively high. Genetic investigation showed that she was homozygous for the CYP2B6 G516T allele, resulting in slow hepatic metabolism. After the dosage of efavirenz was lowered, all neuropsychiatric symptoms subsided.

Different classes of EGFR inhibitors may have different potential to improve local tumour control after fractionated irradiation: a study on C225 in FaDu hSCC

BACKGROUND AND PURPOSE

Previous experiments reported from this laboratory have shown that simultaneous application of the selective epidermal growth factor receptor tyrosine kinase (EGFR-TK) inhibitor BIBX1382BS during fractionated irradiation significantly prolonged growth delay of FaDu human squamous cell carcinoma but did not improve local tumour control. The present study investigates the effect of the EGFR monoclonal antibody (mAb) C225 on local tumour control of FaDu tumours after combined treatment with single dose and fractionated irradiation to address whether different classes of EGFR inhibitors have different potential to improve the outcome of radiotherapy in the same tumour model.

MATERIAL AND METHODS

In unirradiated tumours, C225 was given either once or 4 times i.p. to the nude mice. Irradiation experiments were performed with graded single doses under clamp hypoxic conditions or with 30 fractions in 6 weeks with graded total doses under ambient blood flow. C225 was given 6h before or 6 h before and 2, 5 and 7 days after single dose irradiation. During fractionated irradiation C225 was given once per week. Experimental endpoints were tumour growth delay and local tumour control 120 after end of irradiation.

RESULTS

C225 treatment resulted in prolongation of tumour growth delay after drug treatment alone as well as after single dose and fractionated irradiation. TCD50 values were reduced from 56.3 Gy [95% CI 50; 62 Gy] after single dose irradiation alone to 46.0 Gy [41;51] (enhancement ratio [ER]=1.22, P<0.01) after 1 C225 injection and 47.7 Gy [44; 51] after 4 injections of the drug (ER=1.18, P=0.06). After fractionated irradiation, tumour control dose 50% (TCD50) was 73.0 Gy [64; 82] in control tumours and 63.1 Gy [57; 69] after simultaneous C225 treatment, corresponding to an ER of 1.2 (P=0.01).

CONCLUSION

Treatment of FaDu hSCC with the anti-EGFR mAb C225 resulted in a significant prolongation of tumour growth delay after single dose and fractionated irradiation. In contrast to previous results on the EGFR-TK inhibitor BIBX1382BS, this prolongation of growth delay translated into a slight but significant improvement of local tumour control. The data indicate that different classes of EGFR inhibitors may have different potential to improve the outcome of radiotherapy in the same tumour model.

Graviperception in ciliates: steps in the transduction chain

Ciliates represent suitable model systems to study the mechanisms of graviperception and signal transduction as they show clear gravity-induced behavioural responses (gravitaxis and gravikinesis). The cytoplasm seems to act as a "statolith" stimulating mechanosensitive ion channels in the cell membrane. In order to test this hypothesis, electrophysiological studies with Stylonychia mytilus were performed, revealing the proposed changes (de- or hyperpolarization) depending on the cell's spatial orientation. The behaviour of Paramecium and Stylonychia was also analyzed during variable acceleration conditions of parabolic flights (5th German Parabolic Flight Campaign, 2003). The corresponding data confirm the relaxation of the graviresponses in microgravity as well as the existence of thresholds of graviresponses, which are found to be in the range of 0.4xg (gravikinesis) and 0.6xg (gravitaxis).

Reversible H-induced switching of the magnetic easy axis in Ni/Cu(001) thin films

A reversible switching of the easy axis of magnetization for Ni on Cu(001) from in plane to out of plane is found by changing the partial pressure of hydrogen in the gas phase around the sample, allowing even for oscillations of the magnetization direction. A quantitative low-energy electron diffraction study of the diffracted intensity versus electron energy [I(E)] shows that the hydrogen-induced spin reorientation transition is accompanied by changes of the tetragonal distortion of the topmost Ni layer upon hydrogen adsorption. Surprisingly, the orientation switch to perpendicular to the surface comes with a relaxation, i.e., reduction of the film's tetragonal distortion rather than its amplification.

The Selective α7 Nicotinic Acetylcholine Receptor Agonist PNU-282987 [N-[(3R)-1-Azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide Hydrochloride] Enhances GABAergic Synaptic Activity in Brain Slices and Restores Auditory Gating Deficits in Anesthetized Rats

Schizophrenic patients are thought to have an impaired ability to process sensory information. This deficit leads to disrupted auditory gating measured electrophysiologically as a reduced suppression of the second of paired auditoryevoked responses (P50) and is proposed to be associated with decreased function and/or expression of the homomeric alpha7 nicotinic acetylcholine receptor (nAChR). Here, we provide evidence that N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide hydrochloride (PNU-282987), a novel selective agonist of the alpha7 nAChR, evoked whole-cell currents from cultured rat hippocampal neurons that were sensitive to the selective alpha7 nAChR antagonist methyllycaconitine (MLA) and enhanced GABAergic synaptic activity when applied to hippocampal slices. Amphetamine-induced sensory gating deficit, determined by auditory-evoked potentials in hippocampal CA3 region, was restored by systemic administration of PNU-282987 in chloral hydrate-anesthetized rats. Auditory gating of rat reticular thalamic neurons was also disrupted by amphetamine; however, PNU-282987 normalized gating deficit only in a subset of tested neurons (6 of 11). Furthermore, PNU-282987 improved the inherent hippocampal gating deficit occurring in a subpopulation of anesthetized rats, and enhanced amphetamine-induced hippocampal oscillation. We propose that the alpha7 nAChR agonist PNU-282987, via modulating/enhancing hippocampal GABAergic neurotransmission, improves auditory gating and enhances hippocampal oscillatory activity. These results provide further support for the concept that drugs that selectively activate alpha7 nAChRs may offer a novel, potential pharmacotherapy in treatment of schizophrenia.

Development of an optical trap for microparticle clouds in dilute gases

Long-duration experiments with clouds of microparticles are planned for the ICAPS facility on board the International Space Station ISS. The scientific objectives of such experiments are widespread and are ranging from the simulation of aerosol behaviour in Earth's atmosphere to the formation of planets in the early solar system. It is, however, even under microgravity conditions, impossible to sustain a cloud of free-floating, microscopic particles for an extended period of time, due to thermal diffusion and due to unavoidable external accelerations. Therefore, a trap for dust clouds is required which prevents the diffusion of the particles, which provides a source of relative velocities between the dust grains and which can also concentrate the dust to higher number densities that are otherwise not achievable. We are planning to use the photophoretic effect for such a particle trap. First short-duration microgravity experiments on the photophoretic motion of microscopic particles show that such an optical particle-cloud trap is feasible. First tests of a two-dimensional trap were performed in the Bremen drop tower.

Fullerene quantum gyroscope

We report the observation of quantized rotational states of a diatomic C2 unit in solid endohedral fullerene C(2)Sc(2)@C(84). The rotational transitions induce a periodic line pattern in the low energy Raman spectrum. The rotational constant B and the C-C distance were found to be 1.73 cm(-1) and 0.127 nm, respectively. Density functional calculations revealed an intrinsic rotational barrier of the order of only a few meV for the C2 unit. The Schrödinger equation involving the potential barrier was solved and the Raman tensor matrix elements were calculated, yielding good quantitative agreement with the experiment. To our best knowledge this is the first intrinsic rotational spectrum of a diatomic plane molecular rotor.

Sympathetic and parasympathetic activation in heart rate variability in male hypertensive patients under mental stress

Disturbed sympathetic and also parasympathetic activity of the autonomic nervous system points to pathological alterations in the cardiovascular system. Untreated hypertensive subjects were examined with respect to the question of whether an increase in sympathetic activity necessarily goes along with a reduction in parasympathetic activity, and whether 'delayed' recovery behaviour after mental stress could be an indicator of a disturbed cardiovascular function. In 20 male hypertensive (HT) and 20 normotensive (NT) subjects (control group), heart rate variability (HRV) was compared during rest and under mental stress. The testing procedure consisted of the following phases: habituation, arithmetic tasks without and with interference, recovery. HRV was analysed using the trigonometric regressive spectral analysis (TRS). Proceeding from the total variance (ms2), the weighted averaged frequency (Hz) and the variance parts (ms2) in the frequency bands 'low frequency' (LF-band: 0.04-0.15 Hz) and 'high frequency' (HF-band: 0.15-0.40 Hz) were explored. The variance part modulated by spontaneous breathing within the HF-band was assessed additionally. The variance part in the LF-band under mental stress was significantly increased in the HT group (P<0.01). Activity in the HF-band (without the respiration-dependent part) under mental stress did not differ between both groups, whereas the breathing-modulated part of variance in the HF-band was reduced in the HT subjects. During the recovery period in the HT group, the weighted averaged frequency was still elevated compared to baseline, and the variance part in the LF-band was increased, which may point to delayed recovery behaviour. In addition, by using a discriminant analysis 85% of all subjects were reclassified to the original groups, all HT subjects being assigned 'correctly'. Spectral variance parameters enable early discovery of altered cardiovascular regulation. Respiration influences variance in the HF-band in hypertensive subjects and should therefore be paid attention to. The variance part in the LF-band, weighted averaged frequency and the respiration-modulated variance in the HF-band turned out to be the most valid parameters for the differentiation between NT and HT subjects.

Chronic Necrotizing Pulmonary Aspergillosis Complicated by Pneumothorax

A 61-year-old man presented with left-sided pneumothorax. On the chest computed tomograghy (CT), severe bilateral emphysema and left-sided pleural thickening were seen. His pneumothorax was drained with a chest tube. Because of a persistent air leakage, video-thoracoscopic wedge-resection of the suspected fistula and muscle-sparing minithoracotomy with extensive wedge resections of the left upper lobe were performed. Biopsy specimens showed micronodular mycetomas with septate hyphae highly suggestive of Aspergillus. The fungus destructed the lung tissue without vessel invasion. The patient had not been taking immunosuppressant drugs and had no prior opportunistic infections. Itraconazole was begun, the lung was expanded and the patient recovered. We propose that extensive resection of affected lung tissue in combination with long-term antifungal therapy with itraconazole is a valuable therapeutic option in patients with a complicated course of chronic necrotizing pulmonary aspergillosis (CNPA).

Adjuvant inhibition of the epidermal growth factor receptor after fractionated irradiation of FaDu human squamous cell carcinoma

BACKGROUND AND PURPOSE

Experiments performed by others have shown that inhibition of EGFR before and after single dose irradiation prolonged growth delay and improved local tumour control. This suggests that adjuvant EGFR inhibition can inactivate clonogens that survived irradiation. To test this hypothesis local tumour control was investigated after fractionated radiotherapy and adjuvant EGFR-TK inhibition.

MATERIALS AND METHODS

FaDu hSCC xenografts were irradiated with 30 fractions in 6 weeks with total doses of 30-100Gy. After the end of fractionated irradiation, BIBX1382BS was administered daily orally over a time period of 75 days. Tumour volumes were determined two times per week, the volume doubling time during adjuvant treatment was calculated for progressing and recurrent tumours. Local tumour control was investigated 120 days after end of irradiation.

RESULTS

Adjuvant BIBX1382BS significantly reduced the tumour growth rate but did not improve local tumour control. The TCD(50) values were 66.1Gy (95% C.I.: 59; 73Gy) after adjuvant BIBX1382BS treatment and 67.9Gy (61; 75Gy) for control tumours (P=0.9).

CONCLUSIONS

These data indicate that, although growth of recurrent tumour cells after irradiation is dependent on the EGFR pathway, tumour cells retain their clonogenic potential despite of EGFR inhibition. The results imply also that a decreased tumour growth rate does not necessarily allow conclusions on enhanced inactivation of clonogenic cells when antiproliferative drugs are combined with radiation.

Facial expression recognition and subthalamic nucleus stimulation

BACKGROUND

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor signs in Parkinson's disease. However, clinical studies suggest that DBS of the STN may also affect cognitive and emotional functions.

OBJECTIVE

To study the impact of STN stimulation in Parkinson's disease on perception of facial expressions.

RESULTS

There was a selective reduction in recognition of angry faces, but not other expressions, during STN stimulation.

CONCLUSIONS

The findings may have important implications for social adjustment in these patients.

Repopulation of moderately well-differentiated and keratinizing GL human squamous cell carcinomas growing in nude mice

PURPOSE

It has been suggested that, reminiscent of the regulated proliferative response of normal squamous epithelium, squamous cell carcinomas that have preserved characteristics of differentiation have a greater repopulation capacity during fractionated irradiation than undifferentiated tumors. The aim of the present study was to investigate repopulation in moderately well-differentiated and keratinizing GL human squamous cell carcinomas in nude mice.

METHODS AND MATERIALS

GL human squamous cell carcinomas were transplanted s.c. into the right hind leg of NMRI nu/nu mice. Irradiation was performed with 5.4 Gy fractions under clamp hypoxia or with 2 Gy fractions under ambient conditions. Six, 12, or 18 fractions were given daily, every second day, or every third day. Graded top-up doses were applied under clamp hypoxia to determine the tumor control dose 50% (TCD(50)). A total of 20 TCD(50) assays were performed and analyzed using maximum-likelihood techniques.

RESULTS

With an increasing number of daily 5.4 Gy fractions under clamp hypoxia, the top-up TCD(50) values decreased significantly from 50.9 Gy (95% CI: 47, 54) after single doses to 0 Gy after 18 fractions. For the same number of fractions, the top-up TCD(50) increased with increasing overall treatment time. The results are consistent with a constant repopulation rate with a clonogenic doubling time (T(clon)) of 12.7 days (8.6, 16.8). Under ambient blood flow, the top-up TCD(50)s for daily 2 Gy fractions decreased significantly, but were less pronounced than for 5.4 Gy fractions under clamp hypoxia. For a given number of fractions under ambient conditions, the top-up TCD(50)s did not increase significantly with overall treatment time, except for irradiation with 12 fractions in 36 days compared to 12 and 24 days. The T(clon) value from these data was 24.0 days (11.6, 36.4).

CONCLUSION

Our data demonstrate a slow but significant rate of repopulation of clonogenic tumor cells during fractionated irradiation of GL human squamous cell carcinomas under clamp hypoxia without indication of a change of the repopulation rate during treatment. Less pronounced repopulation was observed for irradiation under ambient conditions, which might be explained by preferential survival of hypoxic and therefore nonproliferating cells. Taken together with our previous studies on poorly differentiated FaDu tumors (Petersen et al., IJROBP 2001;51:483-493), the results support important heterogeneity of kinetics and mechanisms of repopulation, in particular of the influence of the oxygenation status of surviving clonogenic cells on the repopulation rate during fractionated irradiation, in different experimental squamous cell carcinoma.

Viability of the myocardium after twenty-four-hour heart conservation--a preliminary study

BACKGROUND

Orthotopic heart transplantation following ischemic times beyond four hours is associated with increased risk of early graft failure. The use of modern myocardial preservation strategies could enable safe transplantation after long-term conservation. In this study, we tested a new myocardial protection regime in an experimental model of 24 h storage.

METHODS

Orthotopic heart transplantations (n=15) were performed in a pig model. Donor hearts were flushed with Bretschneider solution, excised, and stored for 24 hours at 4 degrees C. During implantation, controlled reperfusions with substrate-enriched leukocyte-depleted blood cardioplegia were performed after each anastomosis. Blood cardioplegia contained 1 mmol/l of the Na(+)-H(+)-exchange inhibitor HOE 642 and 100 mg/l of adenosine. Controlled reperfusion was continued with leukocyte-depleted blood for 20 min. A microaxial pump was inserted after heart transplantation and circulatory assistance was maintained for five hours to prevent right heart failure.

RESULTS

No initial graft failure could be observed. Thirteen hearts could be weaned from extracorporeal circulation. Due to bleeding problems, kidney and lung failure only five hearts could be included in the final analysis. Hemodynamics of these hearts remained stable with epinephrine at 0.1 micro g/kg/min. Myocardial oxygen consumption 20 min after start of reperfusion (5.3+/-2.0 ml/100 g/min) did not differ significantly versus baseline (6.8+/-2.0 ml/100 g/min). Oxygen extraction six hours after heart transplantation was also well preserved compared to baseline (58.0+/-10.2 versus 49.2+/-8.8 %). Histological examination six hours after transplantation using luxol fast blue staining revealed that only 1.0 % of the myocytes were irreversibly damaged.

CONCLUSIONS

The data indicate full viability of the myocardium after 24 h conservation. The preservation technique described could contribute to the extension of conservation times in heart transplantation and enable transplantation of marginal donor hearts.

Multipole induced splitting of metal-cage vibrations in crystalline endohedral D2d-M2@C84 dimetallofullerenes

Metal-carbon cage vibrations of crystalline endohedral D2d-M2@C84 (M=Sc,Y,Dy) dimetallofullerenes were analyzed by temperature dependent Raman scattering and a dynamical force field model. Three groups of metal-carbon cage modes were found at energies of 35-200 cm(-1) and assigned to metal-cage stretching and deformation vibrations. They exhibit a textbook example for the splitting of molecular vibrations in a crystal field. Induced dipole-dipole and quadrupole-quadrupole interactions account quantitatively for the observed mode splitting. Based on the metal-cage vibrational structure it is demonstrated that D2d-Y2@C84 dimetallofullerene retains a monoclinic crystal structure up to 550 K and undergoes a transition from a disordered to an ordered orientational state at a temperature of approximately 150 K.

[Mechanical circulatory assist devices in acute and chronic heart failure]

The clinical use of mechanical circulatory assist devices as bridge to transplantation has been proved as life-saving therapy in a large population of patients. Learning from the clinical experience the construction of the blood pumps has been markedly improved over the last years. The better outcome of the patients has enabled a broader use of ventricular assist devices. The novel axial pumps are designed for long-term circulatory support. After further reduction of device related complications (first of all thromboembolic events) these systems may provide a future alternative to heart transplantation.