[Airway management for lung separation in thoracic surgery : An update]. / Atemwegsmanagement zur Seitentrennung der Lunge bei thorakalen Eingriffen : Ein Update.

One of the main tasks in every anesthetist's routine clinical practice is securing the airway. This also includes techniques for lung isolation and one-lung ventilation in thoracic surgery and in intensive care medicine. The anesthesiologist has various methods available to achieve one-lung ventilation. This article presents the most commonly used methods for lung isolation. These include the double lumen tube, the bronchus blockers by Arndt and Cohen, the EZ blocker, the Uniblocker, the Univent tube and the VivaSight-DL™. The effects of the one-lung ventilation are not described in detail and for this the reader should refer to the appropriate literature. This article is intended to provide an overview of the various possibilities for lung separation, especially for physicians in continued medical education and also for physicians who rarely use these procedures.

Microemulsion-made gadolinium carbonate hollow nanospheres showing magnetothermal heating and drug release.

Gadolinium carbonate (Gd2(CO3)3) hollow nanospheres and their suitability for drug transport and magnetothermally-induced drug release are presented. The hollow nanospheres are prepared via a microemulsion-based synthesis using tris(tetramethylcyclopentadienyl)gadolinium(iii) and CO2 as the starting materials. Size, structure and composition of the as-prepared Gd2(CO3)3 hollow nanospheres are comprehensively validated by several independent analytical methods (HRTEM, HAADF-STEM, DLS, EDXS, XRD, FT-IR, DTA-TG). Accordingly, they exhibit an outer diameter of 26 ± 4 nm, an inner cavity of 7 ± 2 nm, and a wall thickness of 9 ± 3 nm. As a conceptual study, the nanocontainer-functionality of the Gd2(CO3)3 hollow nanospheres is validated upon filling with the anti-cancerogenic agent doxorubicin (DOX), which is straightforward via the microemulsion (ME) strategy. The resulting DOX@Gd2(CO3)3 nanocontainers provide the option of multimodal imaging including optical and magnetic resonance imaging (OI, MRI) as well as magnetothermal heating and drug release. As a proof-of-concept, we could already prove the intrinsic DOX-based fluorescence, a low systemic toxicity according to in vitro studies as well as the magnetothermal effect and a magnetothermally-induced DOX release. In particular, the latter is new for Gd-containing nanoparticles and highly promising in view of theranostic nanocontainers and synergistic physical and chemical tumor treatment.

Phrenic palsy and analgesic quality of continuous supraclavicular vs. interscalene plexus blocks after shoulder surgery.

BACKGROUND: Hemidiaphragmatic palsy is a common consequence of the interscalene brachial plexus block. It occurs less commonly with the supraclavicular approach. Register data suggest that the analgesic quality of a supraclavicular blockade is sufficient for arthroscopic shoulder surgery, although data on the post-operative analgesic effect are lacking. METHODS: After approval by the ethics committee, patients having arthroscopic shoulder surgery under general anaesthesia were randomized to receive a continuous interscalene or supraclavicular blockade. Phrenic nerve function was evaluated through ultrasound examination of the diaphragm in combination with spirometry. Pain scores at rest and activity etc. were determined before catheter insertion, during observation in the post- anaesthesia care unit (PACU) and on post-operative day 1 (POD1). The initial application of 10 ml of ropivacaine 0.2% was followed by continuous application of 4 ml of ropivacaine 0.2%, plus a patient controlled analgesia (PCA) bolus of 4 ml/h. RESULTS: One hundred and twenty patients were randomized, of which 114 data sets were analysed. Complete hemidiaphragmatic paresis occurred in 43% of the interscalene group vs. 24% in the supraclavicular group during PACU stay. Rates of dyspnoea and hoarseness were similar. Horner's syndrome occurred in 21% of the interscalene but only 3% of the supraclavicular group on POD1. Pain scores were comparable for pain at rest and during stress at each time point. CONCLUSIONS: This trial showed a significantly greater incidence of phrenic nerve palsy of the interscalene group in PACU, but not on POD1. Post-operative analgesic quality was similar in both groups. Continuous supraclavicular blockade is a suitable alternative to the continuous interscalene technique.

A blue luminescent MOF as a rapid turn-off/turn-on detector for H2O, O2 and CH2Cl2, MeCN: ∞³[Ce(Im)3ImH]·ImH.

The blue emitting luminescent MOF ∞³[Ce(Im)3ImH]·ImH forms a 3D-framework with Kagomé net topology. The framework exhibits an intense blue luminescence which can be retained upon activation of the MOF with the formula ∞³[Ce(Im)3ImH]. The luminescence is metal-based due to parity-allowed 5d-4f-transitions. Time-dependent investigations of the interaction with liquid and gas analytes show that the MOF ­ by utilising 5d-4f-transitions of Ce(3+) ­ can be used as a high-speed "turn-off" detector for water and oxygen in dry air. Other protic or polar solvents, like methanol, acetone or pyridine, which also show a "turn-off"-effect can be distinguished from water-detection either on a time scale (ranging up to 250,000 : 1) or a shift of the chromaticity, the latter being pronounced for MeOH. The fast time-dependent decrease of the luminescence intensity for water arises from an extremely fast hydrolysis and is irreversible. Polar aprotic molecules like dichloromethane and acetonitrile can also result in a "turn-on"-effect of the luminescence intensity due to their behaviour as additional sensitizers for Ce(3+)-emission. We conclude that the cerium-MOF can be utilised in gas and liquid sensing applications as a detector material for water and oxygen in dry air. The luminescence is intense with good quantum yield between 55% (as-synthesised) and 36% (activated). This implies that only milligram amounts of the material are needed to detect the analyte species and is especially useful, as the MOF can be directly used as-synthesised for water detection in applications for which an irreversible signal change is desired, e.g. preventing a signal change upon unwanted re-drying.

[Holistic therapy of chronic heart failure]. / Ganzheitliche Behandlung der chronischen Herzinsuffizienz.

The rising prevalence and increasing disease-related costs render chronic heart failure a rapidly growing socioeconomic challenge. The concerted action of guideline-adjusted therapy and holistic patient care is essential to achieve improvements in mortality, morbidity, functional status and quality of life of patients with symptomatic heart failure. Holistic care strategies comprise consideration of comorbidities and individual needs, lifestyle recommendations and multidisciplinary management programs for high-risk symptomatic patients in addition to basic medication and surgical therapies. For optimal patient care and coaching, seamless interaction is required between in-hospital treatment and outpatient facilities. Moreover, the palliative needs of heart failure patients need to be considered, a topic that is currently not receiving enough attention.

In situ observation of the melting and sintering of submicron-sized bismuth particles.

The sintering and melting of submicron-sized bismuth particles were studied in situ via scanning electron microscopy. The relevant bismuth particles were prepared via a polyol-mediated synthesis, which results in spherical and non-agglomerated particles, about 250 nm in size. The samples as well as suitable references were deposited on a heater stage assembly inside a scanning electron microscope. Both were investigated up to temperatures of 480 degrees C. Surprisingly, sample areas continuously scanned by the electron beam showed neither sintering nor melting of submicron-sized bismuth, whereas melting was observed at temperatures between 250 and 270 degrees C in non-scanned areas. This behavior was ascribed to an electron-beam-induced decomposition of organic stabilizers that adhered on the bismuth particles to form a thin layer of amorphous carbon. For experimental verification of this hypothesis, controlled carbon coating of submicron-sized bismuth particles was conducted.

Muscle activation during lower body resistance training.

This study evaluated the biceps femoris (BF), rectus femoris (RF), and vastus lateralis (VL) activation and activation ratios of a variety of resistance training exercises characterized by knee extension, and determined if subject strength or gender affects these variables. The exercises evaluated included the leg extension, squat, deadlift, lunge, and step up. Subjects included 20 athletes and recreationally active college students. Electromyography (EMG) of the muscles expressed as a percentage of maximum voluntary isometric contraction (MVIC), as well as the BF to RF and BF to VL EMG ratio, were determined for each exercise. There was no significant interaction between gender and exercise type for the RMS EMG of the BF (p = 0.67), RF (p = 0.53), or VL (p = 0.06). Main effects were found for the RMS EMG of the BF (p = 0.00), RF (p = 0.00), and VL (p = 0.00), as well as the RMS EMG of the BF to RF activation ratio (p = 0.00) and BF to VL activation ratios (p = 0.003), between exercises. Peak RMS EMG was also assessed. Post hoc analysis identified specific differences in muscle activation and ratios between exercises. Clinicians should consider the magnitude of muscle activation and activation ratios when prescribing hamstring and quadriceps exercises.

Afghan refugees and their general practitioners in The Netherlands: to trust or not to trust?

In-depth interviews with Afghan refugees living in The Netherlands about their experience of healthcare, have led to a series of narratives. This article focuses on the relationship between the refugee-patients and their general practitioners (GPs) from the participants' point of view. It was possible to distinguish four different types of narrative, by analysing the individual interviews into critical episodes. Building trust was identified as the crucial issue. A number of possible explanations are given for the differences found. Links are made to participant expectations in respect of health and healthcare and to their personal and social resources. The GP has a key role in the Dutch healthcare system, but is a novel phenomenon for refugees arriving from Afghanistan. The development of a relationship of trust is sometimes compromised by negative personal experience and also by stories relating such experiences circulating in the Afghan community. The elements that constituted positive and negative episodes and led to the development or undermining of trust were identified in the narratives. Negative experience tended to be interpreted as a sign of prejudice on the part of the healthcare professional. The findings of this study are discussed in the wider context of research into patient priorities in general practice.

Worries are the mother of many diseases: general practitioners and refugees in the Netherlands on stress, being ill and prejudice.

OBJECTIVE: To confront the views of refugee patients and general practitioners in the Netherlands, focusing on medically unexplained physical symptoms (MUPS). METHODS: The study is based on in depth interviews with refugees from Afghanistan (n = 36) and Somalia (n = 30). Additionally, semi-structured interviews were conducted with 24 general practitioners. Text fragments concerning the relationship between mental worries and health or physical ailments were subject of a secondary analysis, the results of which are presented. RESULTS: Medically unexplained physical symptoms were a key issue for both refugees and GPs. The GPs saw MUPS as a significant part of the illness presentation by refugee patients. Refugees felt GPs were often prejudiced, too readily using their difficult background as an explanation for physical symptoms. A 'general narrative' circulating in the refugee communities undermines trust. The GPs applied different strategies in dealing with MUPS presented by their refugee patients. A 'human interest strategy' is distinguished from a 'technical strategy'. The results are discussed in the wider context of the literature on MUPS and patient satisfaction. CONCLUSION: No fundamental difference in paradigms was found between refugees and GPs as to the negative influence worries and bad experiences can have on health. For a fruitful cooperation to develop, based on trust, GPs need to invest in the relationship with individual refugees, and avoid actions based on prejudice. PRACTICE IMPLICATIONS: The importance of (a lack of) trust is underestimated in medical practice. Phenomena undermining trust are often out of sight for practitioners. Critical reflection is needed on the strategies practitioners employ to deal with MUPS.

Adhesion of Colloidal SiO(2) Particles on ZnS-Type Phosphor Surfaces.

The interaction between colloidal SiO(2) particles and the surface of ZnS-type phosphors has been studied. The green emitting phosphor ZnS:Cu,Al,Au applied in color television tubes was chosen as a model compound. After the surface of the phosphor particles (d(50)=5.0 µm) was treated in different manners like washing with H(2)O, HCl, or H(2)O(2) as well as precoating with colloidal ZnO particles (d(50)=81 nm), colloidal SiO(2) particles (d(50)=207 nm) were added. Thereafter, the amount of adhered SiO(2) was investigated based on SEM and ESCA analysis. By ESA measurements the surface charge of the colloids and the differently treated ZnS materials was investigated. Based on the experimental results it can be concluded that colloidal SiO(2) particles adhere sufficiently only if ZnO is present on the ZnS surface. The SiO(2) particles are located on top of the ZnO. Finally, the attractive interactions in the system ZnS-ZnO-SiO(2) are discussed in more detail. Copyright 2000 Academic Press.

Adhesion of Colloidal ZnO Particles on ZnS-Type Phosphor Surfaces.

Chemical and physical aspects of the adhesion of colloidal ZnO particles (d(50)=81 nm) on the surface of ZnS-type phosphors have been studied. Here, the green-emitting phosphor ZnS:Cu,Al,Cu (d(50)=5.0 µm) applied in TV screens was chosen as model compound. The ZnS material was pretreated in various ways (H(2)O, HCl, H(2)O(2)) and reacted thereafter with a suspension containing colloidal ZnO particles. Analytical investigations (SEM, ESCA) have shown that the adhesion of colloidal ZnO particles is strongly affected by the degree of hydrolysis of the ZnS surface. Electroacoustic investigations (ESA) prove that both types of surfaces, hydrolyzed ZnS as well as colloidal ZnO, are positively charged. Even so, adhesion of ZnO particles is encouraged very much under these conditions, indicating that secondary attractive forces (electrostatic interaction, chemical bonding) determine the amount of colloidal ZnO adhered on a ZnS-type phosphor. Copyright 2000 Academic Press.

Long-template DNA polymerase chain reaction for the detection of the bcr/abl translocation in patients with chronic myelogenous leukemia.

In most patients with chronic myelogenous leukemia (CML) primitive hematopoietic progenitors carry the acquired reciprocal bcr/abl gene rearrangement t(9;22)(q34.1; q11.21). However, not all of the progenitor cells express the bcr/abl hybrid mRNA or the p210 fusion protein. These cells, therefore, might escape detection by techniques that are based on expression of the fusion gene. To circumvent this problem, we established a new detection method for the rearrangement at the DNA level. Because breakpoints might occur in a very large genomic region (>200 kb), we developed a long-template DNA-PCR (LT-DNA-PCR). In 22 of 59 CML patients, fragments of up to 19 kb could be amplified. Furthermore, 6 of 7 leukapheresis products of three bcr/abl-positive patients which were collected after mobilization chemotherapy and had been shown to be negative for the bcr/abl rearrangement by FISH and by RT-PCR were clearly positive by LT-DNA-PCR. Using a specific pair of primers, it is possible to detect the presence of, and to characterize, the individual gene rearrangement. This approach could serve for diagnostic purposes as well as detection of minimal residual disease under cytotoxic therapy or after purging regimens, being independent of expression of the bcr/abl hybrid mRNA or the fusion protein.

Stimulation of fracture healing by local application of humoral factors integrated in biodegradable implants.

Growth stimulation by growth hormones or by IGF-1 is well known whereas publications about stimulation of fracture healing with these substances are rare. One of the main effects of IGF-1 is angiopoiesis which consequently may be expected to induce and accelerate the soft tissue callus formation. BMP-2 is a stimulator for osteoclasts and osteoblasts and prepares the osseous reparation. RhBMPs, mostly BMP-2, are already used in the reconstruction of the cranial vault. The main disadvantage of these proteins is the quick inactivation after about 20-30 minutes. Local stimulation without systemic effects might be avoided by releasing a low but constant dose of IGF-1 or BMP. We speculate that the combination of a reasonable implant with an integrated drug release system may enlarge the field of application of biodegradable implants in the treatment of fractures. Such an implant might remarkably reduce the time for fracture healing and also lower the costs of postoperative treatment. In this paper we report our animal models in which we have tested constructive principles of biodegradable implants, we present the first clinical experiences with polyactates (PLLA) in the osteosynthesis of children, and we describe our inventions concerning drug releasing implants. 1) PLLA-implants a) The animal models We performed on oblique osteotomy of the right metacarpal bone in 48 juvenile calves and osteoplastic reconstructions of the cranial vault in 28 juvenile Göttinger minipigs. Biodegradable osteosynthesis with PLLA implants led to results as good as with conventional materials in both animal models, so that we proceeded to clinical evaluation in children. b) The clinical application in children 35 children, aged 6 weeks to 17 years, had resorbable osteosynthesis of their cranioplasties for correction of congenital malformations and posttraumatic reconstructions. The follow-up ranged from 5-15 years. 2) Invention of a drug-releasing system IGF-1 or BMP-2 is planned to be incapsulated by evaporation technique into nanospheres of low PDLLA (Poly-DL-Lactite) with a molecular weight of about 20,000 and an expected resorption time of 2-3 weeks (patent pending). 3) Concept of our drug-releasing resorbable implants Plates could be built up in multilayers of PDLLA sheets, separated by a spongiform matrix containing the IGF-1- or BMP-2-loaded nanospheres. The screws are hollow due to an internal driving system. The specially designed thread could also contain nanospheres, which would be brought into the cortical bone and the medullary space. The cavity of the screw is filled up with nanospheres after tightening.

Role of microglia in neuronal cell death in prion disease.

To elucidate the role played by the prion protein in scrapie pathogenesis, we performed experiments with PrP27-30 isolated from scrapie-infected hamster brains in cell culture and studied in vivo the temporal and spatial correlation between deposition of the disease-associated isoform of the prion protein (PrPSc), microglial activation and neuronal cell death in mice infected with scrapie strains 79A, ME7 and RML. The results presented here show that cellular expression of PrPc and the presence of microglia are necessary for the neurotoxicity of PrPSc in vitro. In vivo, accumulation of protease-resistant prion protein was detected early in the incubation period using the histoblot technique. Microglial activation was also detected early in the incubation period of all models studied. Both the time course and the spatial distribution of microglial activation closely resembled the pattern of PrPSc deposition. Microglial activation clearly preceded the detection of apoptotic neuronal cell death which was assessed using the in situ end-labeling technique (ISEL). Taken together, our results indicate that microglial activation is involved in the neurotoxicity of PrPSc both in vitro and in vivo.

Dental units: an environmental study of sources of potentially pathogenic mycobacteria.

SETTING: Infections caused by non-tuberculous mycobacteria (NTM) are generally thought to be acquired from environmental sources. However, little is known about the situations in which transmission occurs. OBJECTIVE: In an attempt to identify situations of relevant contact with NTM we investigated the water to which patients are exposed during dental treatment. DESIGN: The concentration and species of NTM were determined in 43 cooling and spray water samples from 21 dental units in ten offices. In addition, mycobacterial colonization of 16 biofilm samples from the waterlines of two dental units was investigated. RESULTS: The mean NTM concentration in the water samples was 365 colony-forming units (cfu) per mL, exceeding the mean drinking water concentration by a factor of almost 400. In the biofilm samples the mean NTM density amounted to 1165 cfu/cm2. The species identified included Mycobacterium gordonae, M. flavescens, M. chelonae, 'M. chelonae-like organism' and M. simiae. CONCLUSION: High numbers of NTM may be swallowed, inhaled or inoculated into oral wounds during dental treatment, possibly resulting in colonization, sensitization or infection. Mycobacterial proliferation in biofilms forming within dental units may explain the extent of NTM contamination of dental spray and cooling water.

[Group work with relatives of Alzheimer patients--a systemic approach]. / Gruppenarbeit mit Angehörigen von Alzheimer-Kranken--ein systemischer Ansatz.

Dementia does not only infringe the patient's but also his caregivers' lives. The social system surrounding the patient is facing a heavy burden. The care is negatively affected by two components: lack of support from outside and problems within the relationship of patient and caregiver. In a support group for caregivers of Alzheimer patients we therefore adapted a combined approach of psycho-education and system therapy. We centered on the adverse patterns of behavior between patient and caregiver and the broadening of the support system. Techniques from systemic family therapy were used. Two cases illustrate the possibilities of this new approach to group therapy with caregivers of Alzheimer patients.