Operation time and clinical outcomes for open infrarenal abdominal aortic aneurysms to remain stable in the endovascular era

Objective

Endovascular aortic repair (EVAR) has become a routine procedure worldwide. Ultimately, the increasing number of EVAR cases entails changing conditions for open surgical repair (OSR) regarding patient selection, complexity, and surgical volume. This study aimed to assess the time trends of open abdominal aortic aneurysm (AAA) repair in a high-volume single center in Austria over a period of 20 years, focusing on the operation time and clinical outcomes.

Materials and methods

A retrospective analysis of all patients treated for infrarenal AAAs with OSR or EVAR between January 2000 and December 2019 was performed. Infrarenal AAA was defined as the presence of a >10-mm aortic neck. Cases with ruptured or juxtarenal AAAs were excluded from the analysis. Two cohorts of patients treated with OSR at different time periods, namely, 2000-2009 and 2010-2019, were assessed regarding demographical and procedure details and clinical outcomes. The time periods were defined based on the increasing single-center trend toward the EVAR approach from 2010 onward.

Results

A total of 743 OSR and 766 EVAR procedures were performed. Of OSR cases, 589 were infrarenal AAAs. Over time, the EVAR to OSR ratio was stable at around 50:50 (p = 0.488). After 2010, history of coronary arterial bypass (13.4% vs. 7.2%, p = 0.027), coronary artery disease (38.1% vs. 25.1%, p = 0.004), peripheral vascular disease (35.1% vs. 21.3%, p = 0.001), and smoking (61.6% vs. 34.3%, p < 0.001) decreased significantly. Age decreased from 68 to 66 years (p = 0.023). The operation time for OSR remained stable (215 vs. 225 min, first vs. second time period, respectively, p = 0.354). The intraoperative (5.8% vs. 7.2%, p = 0.502) and postoperative (18.3% vs. 20.8%, p = 0.479) complication rates also remained stable. The 30-day mortality rate did not change over both time periods (3.0% vs. 2.4%, p = 0.666).

Conclusion

Balanced EVAR to OSR ratio, similar complexity of cases, and volume over the two decades in OSR showed stable OSR time without compromise in clinical outcomes.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

The sweet and musky scent of home: biogenic ethylene fine-tunes seed germination in wetlands

Wetlands are known for comparatively high production of biogenic ethylene from decomposed sediment. Because the gas has various well-documented effects on seed physiology, we asked whether it can be a vital seed germination cue for wetland plants. Specifically, we explored whether ethylene plays an ecological role in (i) breaking/weakening seed dormancy, (ii) broadening the germination niche width, (iii) promoting germination speed or (iv) altering the germination requirements of six plant species with different occurrence along a hydroperiod gradient. In a factorial experiment, both ethylene-treated and untreated seeds were incubated in combinations of temperature (constant versus fluctuating), illumination (light versus darkness) and oxygen (aerobic versus hypoxia) with and without cold stratification. Our results revealed seed exposure to ethylene did not weaken or break dormancy without cold stratification treatment. However, ethylene helped to broaden the germination niche width, increased overall germination percentage and speed of cold-stratified (non-dormant) seeds. This indicates that ethylene helps those seeds that lost dormancy (non-dormant) to sense favourable water-saturated versus flooded substrate depending on their requirement for aerobic versus hypoxic conditions to trigger germination. We conclude that ethylene does not interfere directly with the dormancy-breaking process in autumn-dispersed seeds that are naturally cold-stratified in winter and germinate in spring/summer. However, ethylene plays a crucial ecological role as a 'flood detector' for different wetland plant communities (reed, mudflat, swamp, shallow water) to synchronize germination of non-dormant seeds in the most suitable habitat at the right time.

No evidence for stochastic resonance effects on standing balance when applying noisy galvanic vestibular stimulation in young healthy adults

Noisy galvanic vestibular stimulation (nGVS) at imperceptible levels has been shown to reduce body sway. This reduction was commonly attributed to the mechanism of stochastic resonance (SR). However, it has never been explicitly tested whether nGVS-induced effects on body sway consistently follow a SR-like bell-shaped performance curve with maximal reductions in a particular range of noise intensities. To test this, body sway in 21 young healthy participants was measured during varying nGVS amplitudes while standing with eyes closed in 3 conditions (quiet stance, sway referencing, sinusoidal platform tilts). Presence of SR-like response dynamics in each trial was assessed (1) by a goodness-of-fit analysis using an established SR-curve model and (2) by ratings from 3 human experts. In accordance to theory, we found reductions of body sway at one nGVS amplitude in most trials (75–95%). However, only few trials exhibited SR-like bell-shaped performance curves with increasing noise amplitudes (10–33%). Instead, body sway measures rather fluctuated randomly across nGVS amplitudes. This implies that, at least in young healthy adults, nGVS effects on body sway are incompatible with SR. Thus, previously reported reductions of body sway at particular nGVS intensities more likely result from inherent variations of the performance metric or by other yet unknown mechanisms.

Critical force in active microrheology

Soft solids like colloidal glasses exhibit a yield stress, above which the system starts to flow. The microscopic analogon in microrheology is the untrapping or depinning of a tracer particle subject to an external force exceeding a threshold value in a glassy host. We characterize this delocalization transition based on a bifurcation analysis of the corresponding mode-coupling theory equations. A schematic model that allows analytical progress is presented first, and the full physical model is studied numerically next. This analysis yields a continuous dynamic transition with a critical power-law decay of the probe correlation functions with exponent -1/2. To compare with simulations with a limited duration, a finite-time analysis is performed, which yields reasonable results for not-too-small wave vectors. The theoretically predicted findings are verified by Langevin dynamics simulations. For small wave vectors we find anomalous behavior for the probe position correlation function, which can be traced back to a wave-vector divergence of the critical amplitude. In addition, we propose and test three methods to extract the critical force from experimental data, which provide the same value of the critical force when applied to the finite-time theory or simulations.

A novel rat model for tracheal mucosal damage assessment of following long term intubation

OBJECTIVE

Tracheal mucosal damage is a well-known complication of endo-tracheal intubation and animal models are essential for studying the underlying cellular injury cascade. The novel rat model described here is based on retrograde intubation via tracheotomy and suture fixation of the tube. It aims to simulate the common clinical scenario of tube-related airway damage due to long term intubation.

STUDY DESIGN

Prospective randomized control pilot study.

METHODS

Male Sprague-Dawley were randomly assigned into two groups: control (no intubation, n = 10), one week of intubation (n = 13). The animals were then euthanized and the trachea was sent for histological analysis. Epithelial damage, mucosal thickness, mucosal gland hypertrophy and fibrosis were reviewed.

RESULTS

Intubation procedure survival rate was 84.6% (11/13) and 100% in the control (10/10). The damaged ciliary mechanism was a common finding in the intubated group compared to the preserved normal ciliary architecture in almost all control rats. Average tracheal mucosal thickness was 119.0 ± 21.8 μm for the control group and 254.6 ± 22.8 μm for the intubated group, (p < 0.001). The ciliary damage score was 1.00 ± 0.02 in the intubated group, and 0 ± 0.02 in the control group. (p < 0.001). The (objective) average total tracheal mucosal gland area was 19,530 ± 24,606 in the intubated group and 10,031 ± 23,461 in the control group (p < 0,05). Collagen deposition seems higher in the intubated trachea compared to the control.

CONCLUSIONS

We describe a novel rat-based animal model for simulating tracheal mucosal damage following long term intubation. This animal model is easy to carry out, reproducible and involves containable animal mortality rates.

LEVEL OF EVIDENCE

I.

A novel rat model for assessment of laryngotracheal injury following transoral intubation

OBJECTIVE

Laryngotracheal damage is a well-described complication of endotracheal intubation and animal models are essential for studying the underlying cellular injury cascade. This novel rat model is based on transoral intubation and aims to simulate the common clinical scenario of tube-related airway damage.

METHODS

Prospective randomized control pilot study. 28 male Sprague-Dawley were randomly assigned into three groups: control, 3-h' intubation and 6-h' intubation. The animals were then euthanized and their laryngotracheal complexes sent for histological analysis. Epithelial damage, mucosal thickness and mucosal gland hypertrophy were reviewed.

RESULTS

Total of 13 control animals and 15 intubated animals. 10 intubated animals survived the study protocol. Loss of epithelial surface architecture including damage to the microscopic ciliary mechanism was a common feature amongst all intubated animals. Average mucosal thickness of the larynx (including vocal cords and subglottic area) was 143 ± 88 μm for control rats, 315 ± 101 μm for rats intubated 3 h and 574 ± 174 μm for rats intubated 6 h .This was a statistically significant difference. Average mucosal gland hypertrophy in the laryngeal subsite was 0.41 ± 0.5 in control rats, 1.4 ± 0.5 in rats intubated 3 h and 2.0 ± 0.0 for rats intubated 6 h (statistically significant difference). There was a clear difference between three and 6 h of intubation with poorer mucosal injury parameters for longer intubation.

CONCLUSIONS

We describe a novel rat-based animal model for simulating airway mucosal damage following transoral intubation. This animal model is easy to carry out, reproducible and involves containable animal mortality rates.

Recover recovery style from psychosis: a psychometric evaluation of the German version of the Recovery Style Questionnaire (RSQ)

AIMS

The way an individual handles the experience of psychosis, the so-called 'recovery style', has been shown to substantially affect long-term outcomes. The Recovery Style Questionnaire (RSQ) measures this psychological dimension. The aim of this study was to provide a validation of the German version of the RSQ and to raise awareness for recovery-oriented approaches.

METHODS

The RSQ was translated into German according to the guidelines of the WHO and patients were administered this questionnaire and measures of internalised stigma, psychotic symptoms, illness concept, empowerment, self-esteem and quality of life. Descriptive statistics were demonstrated to characterise the sample. Reliability was assessed in different forms: internal consistency, test-retest reliability and split-half reliability. Items were evaluated with descriptive data and item-total correlations. Convergent and discriminant validity were shown, and a confirmatory factor analysis was performed. In order to ameliorate the model, a post hoc model modification was done.

RESULTS

The sample consisted of 138 patients diagnosed with schizophrenia spectrum disorders (mean age: 35.7 years; 53.6% men; mean duration of illness: 20.6 years) with a mean RSQ overall percentage of 66.12 (s.d. ± 17.43%), mainly representing the categories 'mixed picture' and 'tends towards integration'. The reliability of the RSQ was acceptable with a Cronbach's α of 0.741 and a test-retest coefficient of 0.502. Item-total correlations were not acceptable for 27 of 39 items. Moderate evidence for convergent validity of the RSQ was found. Confirmatory factor analysis revealed that the 13-factor model with 39 items originally proposed was partially poorly replicated in the present sample (χ2 ratio to degrees of freedom (χ2/df) of 1.732, Comparative Fit Index (CFI) of 0.585, Normed Fit Index (NFI) of 0.414, Tucker-Lewis Index (TLI) of 0.508, root mean square error of approximation (RMSEA) of 0.095). The RSQ was modified based on item-total correlations and path coefficients of the single items. The confirmatory factor analysis of the resulting one-factor model with 11 items showed adequate fit to the data (χ2/df of 1.562, CFI of 0.936, NFI of 0.847, TLI of 0.910, RMSEA of 0.083) and demonstrated good model fit.

CONCLUSIONS

Despite partially insufficient psychometric data of the original RSQ, the concept of recovery style is beneficial to psychiatric research and clinical practice. The underlying idea is valuable, and the questionnaire needs further development. Therefore, a short version of the RSQ is proposed.

Neuroplasticity following short-term strength training occurs at supraspinal level and is specific for the trained task

AIMS

Different modalities of strength training cause performance enhancements, which are specific for the trained task. However, the involved mechanisms are still largely unknown. It has been demonstrated that strength training could induce neuroplasticity, which might underlie the performance improvements during the first training sessions. Thus, we hypothesized to find task-specific neuroplasticity after a short-term strength training of two distinct strength tasks.

METHODS

Young healthy male subjects were exposed to 4 sessions of either maximal isometric explosive (EXPL group, N = 9) or slow sustained (SUS group, N = 10) knee extensions. Pre- and post-training, we measured H-reflexes and motor evoked potentials (MEPs) in the vastus lateralis (VL) at the onset of both strength tasks.

RESULTS

Pre- and post-training, H-reflexes remained unchanged in both groups. MEP areas were lower in the trained task in both groups and remained unchanged in the untrained task.

CONCLUSION

This study demonstrated that short-term strength training induces specific neuroplasticity for the trained task only. The fact that MEPs were lower but H-reflex amplitudes remained unchanged at the onset of the trained tasks suggests that strength training elicited neuroplasticity at supraspinal level that most likely reflect an improved task-specific corticospinal efficiency.

A new approach for fat removal in a discontinuous autotransfusion device-concept and evaluation

BACKGROUND

Fat present during blood salvage in orthopaedic or cardiac surgery can pose a risk of fat embolism and should be eliminated before transfusion. Based on observations of central fat accumulation at the bottom of Latham bowls, a fat reduction program was developed using two volume displacements, where blood temporarily is removed and respun in the bowl to force the fat through the RBC sediment.

MATERIALS AND METHODS

Pooled ABO-matched RBC and FFP were adjusted to a haematocrit of 10%, and human fat tissue added to a concentration of 1·25 vol%. In six experiments, blood was processed with the new-generation cell salvage device CS Elite in a newly developed fat reduction program in bowls of three sizes. Volumetric quantification of fat was performed after centrifugation of blood samples in Pasteur pipettes. From volumes, haematocrits and the concentrations of fat, RBC recovery and fat elimination rates were calculated.

RESULTS

Fat removal rates of 93·2 ± 2·8, 97·0 ± 2·1 and 99·6 ± 0·3% were observed with a 70-ml, 125-ml and 225-ml bowl, respectively, and even higher rates when removal rates were calculated one cycle. At the same time, high RBC recovery and plasma elimination rates were maintained, not significantly different to the default program mode.

CONCLUSION

Modifications in process parameters and sequence led to a fat reduction program that significantly improves fat removal with the Cell Saver Elite from 77·4 ± 5·1% in the default mode to an average of 98·6 ± 1·1%, yielding results equivalent to the continuous cell salvage system (C.A.T.S).

Performance of a new-generation continuous autotransfusion device including fat removal and consequences for quality controls

BACKGROUND AND OBJECTIVES

Cell salvage plays a key role in blood conservation. To maintain high performance, quality management is recommended. Accordingly, a new-generation autotransfusion device was tested for its performance and compared with its predecessor. Two different calculations of quality parameters were applied.

MATERIALS AND METHODS

In an experimental study, the continuous autotransfusion devices CATSmart and Continuous Autotransfusion System (C.A.T.S) plus were tested using banked blood adjusted to a haematocrit of 20% and anticoagulated with heparin 5 U/L. Test blood was processed using an emergency programme, a high-quality programme/smart wash programme and a low-volume wash programme. Samples were taken after the production of 200 mL of red blood cells (RBC) and after the final emptying of the separation chamber. In an additional set of tests, blood containing 1·25% fat was processed with both devices to examine fat removal.

RESULTS

Both devices demonstrated an equally high performance with regards to product hematocrit (Hct); RBC recovery; and elimination rates of protein, heparin and fat. The high fat elimination rate (>99·8%) reported for C.A.T.S plus was confirmed for CATSmart, regardless of the used programme. Samples taken during the ongoing process show a higher haematocrit and RBC recovery rate than samples taken after the final emptying of the separation chamber. Interface sensors were not affected by fat in the blood.

CONCLUSIONS

The new-generation autotransfusion device CATSmart is not inferior to its predecessor and shows high performance with regards to RBC recovery, plasma and fat elimination in all programme modes. Samples for quality controls should be taken during blood processing.

Conditioning hops increase triceps surae muscle force and Achilles tendon strain energy in the stretch-shortening cycle

Postactivation potentiation can improve athletic performance, but the underlying mechanisms are poorly understood. This study investigated the effect of conditioning hops on triceps surae muscle force and tendon strain and its contribution to potentiated stretch-shortening cycle (SSC) performance. Thirty-two subjects participated in two experiments. In both experiments, subjects performed three drop jumps (DJs) after prior conditioning with 10 maximal hops, three unconditioned DJs served as control. Ground reaction forces, kinematics, and triceps surae electromyographic activity were recorded. Ultrasound imaging was used to determine fascicle lengths (FASC) of the gastrocnemius (GM) and soleus muscles (experiment 1) and the length of the Achilles tendon (experiment 2) during the DJs. DJ height after the conditioning hops was significantly higher compared to control DJs (experiment 1: +12% and experiment 2: +19%). A significantly shorter GM FASC during the DJs performed after the conditioning hops coincided with an increased force acting on the triceps surae muscle. Moreover, the triceps surae muscle-tendon unit (MTU) showed increased energy absorption during the eccentric phase of the DJs and increased energy release during the concentric phase. The second experiment revealed a higher Achilles tendon strain in DJs performed after the conditioning hops compared to control DJs. No significant differences in muscle activities were observed. The shorter FASC in GM and the larger Achilles tendon strain facilitated MTU energy transfer from the eccentric to the concentric phase during the DJ. Thereby, conditioning hops improved SSC efficacy and DJ performance.

Postactivation potentiation can counteract declines in force and power that occur after stretching

Stretching can decrease a muscle's maximal force, whereas short but intense muscle contractions can increase it. We hypothesized that when combined, postactivation potentiation induced by reactive jumps would counteract stretch-induced decrements in drop jump (DJ) performance. Moreover, we measured changes in muscle twitch forces and ankle joint stiffness (K_Ankle ) to examine underlying mechanisms. Twenty subjects completed three DJs and 10 electrically evoked muscle twitches of the triceps surae subsequent to four different conditioning activities and control. The conditioning activities were 10 hops, 20s of static stretching of the triceps surae muscle, 20s of stretching followed by 10 hops, and vice versa. After 10 hops, twitch peak torque (TPT) was 20% and jump height 5% higher compared with control with no differences in K_Ankle . After stretching, TPT and jump height were both 9% and K_Ankle 6% lower. When hops and stretching were combined as conditioning activities, jump height was not different compared with control but significantly higher (11% and 8%) compared with stretching. TPTs were 16% higher compared with control when the hops were performed after stretching and 9% higher compared with the reverse order. K_Ankle was significantly lower when stretching was performed after the hops (6%) compared with control, but no significant difference was observed when hops were performed after stretching. These results demonstrate that conditioning hops can counteract stretch-related declines in DJ performance. Furthermore, the differences in TPTs and K_Ankle between combined conditioning protocols indicate that the order of conditioning tasks might play an important role at the muscle-tendon level.

Active microrheology in a colloidal glass

We study the dynamics of a probe particle driven by a constant force through a colloidal glass of hard spheres. This nonequilibrium and anisotropic problem is investigated using a new implementation of the mode-coupling approximation with multiple relaxation channels and Langevin dynamics simulations. A force threshold is found, below which the probe remains localized, while above it the probe acquires a finite velocity. We focus on the localized regime, comparing theory and simulations concerning the dynamics in the length scale of the cage and the properties of the transition to the delocalized regime, such as the critical power-law decay of the probe correlation function. Probe van Hove functions predicted by the theory show exponential tails reminiscent of an intermittent dynamics of the probe. This scenario is microscopically supported by simulations.

Non-tuberculous mycobacterial head and neck infections in children: Analysis of results and complications for various treatment modalities

OBJECTIVES

Analyze the results and complications of various surgical interventions in a large cohort of children with non-tuberculous mycobacterial (NTM) head and neck infections and suggest a heuristic treatment protocol for managing this condition while aiming to maximize cure and minimize complications.

METHODS

Retrospective chart review of 104 consecutive patients diagnosed with head and neck NTM at a tertiary paediatric hospital between January 1994 and December 2013 inclusive.

RESULTS

104 patients ranged in age between 8 months to 15 years (mean age 27 months) were reviewed and 97 patients were included in the final analysis. 6 patients excluded due to lack of follow-up and one excluded due to systemic immunocompromised condition. Sub-sites of NTM infections were submandibular (n=48, 46%), cervical (n=40, 38%), parotid (n=18, 17%) and submental (n=4, 4%). Some patients had more than one lesion so counted twice. Higher cure rates were demonstrated for primary excision (81%, p<0.01) versus incisional interventions (44%, p<0.01). Marginal mandibular nerve palsy following surgery was seen in 7 patients (7.2%). This was permanent in 4 patients (4%) and temporary in 3 patients (3%). All children who were complicated with marginal mandibular palsies had lesions in the submandibular region. The rate of palsy for submandibular disease alone was 15%, while 8% presented permanent palsy and 6% temporary. Marginal mandibular nerve palsy was more likely following excisional compared to incisional procedures (6 versus 1 patient, p<0.01). Hypertrophic scarring occurred in 7 patients: 3 patients following excision and 4 patients after an incisional procedure. One patient suffered long term spinal accessory nerve damage presented as winged scapula.

CONCLUSIONS

Excision of NTM provides better cure rates compared to incision although at the expense of long term post-surgical morbidity. Excision should probably be the first line of treatment when the risk for neural damage is low. Incision and drainage with or without antimycobacterial treatment may be the preferred option for at-risk sub-sites (submandibular or parotid) in order to reduce long term morbidity.

Printing medicines as orodispersible dosage forms: Effect of substrate on the printed micro-structure

We present our recent advancements in developing a viable manufacturing process for printed medicine. Our approach involves using a non-contact printing system that incorporates both piezoelectric- and solenoid valve-based inkjet printing technologies, to deliver both active and inactive pharmaceutical materials onto medical-graded orodispersible films. By using two complimentary inkjet technologies, we were able to dispense an extensive range of fluids, from aqueous drug solutions to viscous polymer coating materials. Essentially, we demonstrate printing of a wide range of formulations for patient-ready, orodispersible drug dosage forms, without the risk of drug degradation by ink heating and of substrate damages (by contact printing). In addition, our printing process has been optimized to ensure that the drug doses can be loaded onto the orally dissolvable films without introducing defects, such as holes or tears, while retaining a smooth surface texture that promotes patient adherence and allows for uniform post-coatings. Results show that our platform technology can address key issues in manufacturing orodispersible drug dosage forms and bring us closer to delivering personalized and precision medicine to targeted patient populations.

[Optimization of blood gas analysis in intensive care units : Reduction of preanalytical errors and improvement of workflow]

BACKGROUND

Point of care testing with blood gas analysis (BGA) is an important factor for intensive care medicine. Continuous efforts to optimize workflow, improve safety for the staff and avoid preanalytical mistakes are important and should reflect quality management standards.

AIM

In a prospective observational study it was investigated whether the implementation of a new system for BGA using labeled syringes and automated processing of the specimens leads to improvements compared to the previously used procedure.

MATERIAL AND METHODS

In a 4-week test period the time until receiving the final results of the BGA with the standard method used in the clinical routine (control group) was compared to the results in a second 4-week test period using the new labeled syringes and automated processing of the specimens (intervention group). In addition, preanalytical mistakes with both systems were checked during routine daily use. Finally, it was investigated whether a delay of 10 min between taking and analyzing the blood samples alters the results of the BGA.

RESULTS

Preanalytical errors were frequently observed in the control group where non-deaerated samples were recorded in 87.3 % but in the intervention group almost all samples (98.9 %) were correctly deaerated. Insufficient homogenization due to omission of manual pivoting was seen in 83.2 % in the control group and in 89.9 % in the intervention group; however, in the intervention group the samples were homogenized automatically during the further analytical process. Although a survey among the staff revealed a high acceptance of the new system and a subjective improvement of workflow, a measurable gain in time after conversion to the new procedure could not be seen. The mean time needed for a complete analysis process until receiving the final results was 244 s in the intervention group and 201 s in the control group. A 10-min delay between taking and analyzing the blood samples led to a significant and clinically relevant elevation of the values for partial pressure of oxygen (pO2) in both groups compared to the results when analyzing the samples immediately (118.4 vs. 148.6 mmHg in the control group and 115.3 vs. 123.7 mmHg in the intervention group). When using standard syringes the partial pressure of carbon dioxide (pCO2) was significantly lower (40.5 vs. 38.3 mmHg) whereas no alterations were seen when using the labeled syringes.

CONCLUSION

The implementation of a new BGA system with labeled syringes and automated processing of the specimens was possible without any difficulties under daily clinical routine conditions in this 10-bed intensive care unit (ICU). A gain of time could not be measured but a reduction in preanalytical errors using the labeled syringes with automated processing was found. Delayed analysis of blood samples can lead to significant changes in pO2 and pCO2 depending on the type of syringe used.

Effects of ropivacaine, bupivacaine and sufentanil in colon and pancreatic cancer cells in vitro

The perioperative period is supposed to be a vulnerable period for cancer progression. Results of clinical studies indicate that the use of regional anesthesia can influence and improve oncological outcome of cancer patients. Uncontrolled cell proliferation and resistance to apoptotic cell death are important characteristics of solid tumors. The aim of this study was to investigate the effects of the clinically used local anesthetics ropivacaine or bupivacaine and the opioid analgesic sufentanil on cell proliferation, cell cycle distribution and apoptosis of colon (HT 29 and SW 480) and pancreatic (PaTu 8988t and PANC 1) cancer cell lines in vitro. Cell proliferation was measured by Cell Proliferation ELISA BrdU Assay. Apoptosis was analyzed by annexin V staining and cell cycle distribution was detected by flow cytometry. Ropivacaine, bupivacaine and sufentanil did not change apoptosis rate and cell cycle distribution in clinically concentration. Only high concentrations of ropivacaine or bupivacaine revealed antiproliferative potency. Protective effects of epidural anesthesia observed in clinical studies seem not to be based on direct effects of these drugs on cancer cells.

A landscape of hairy and twisted: hunting for new trichome mutants in the Saskatoon Arabidopsis T-DNA population

A total of 88 new Arabidopsis lines with trichome variation were recovered by screening 49,200 single-seed descent T3 lines from the SK activation-tagged population and from a new 20,000-line T-DNA insertion population (called pAG). Trichome variant lines were classified into 12 distinct phenotype categories. Single or multiple T-DNA insertion sites were identified for 89% of these mutant lines. Alleles of the well-known trichome genes TRY, GL2 and TTG1 were recovered with atypical phenotype variation not reported previously. Moreover, atypical gene expression profiles were documented for two additional mutants specifying TRY and GL2 disruptions. In remaining mutants, ten lines were disrupted in genes coding for proteins not implicated in trichome development, five were disrupted in hypothetical proteins and 11 were disrupted in proteins with unknown function. The collection represents new opportunities for the plant biology community to define trichome development more precisely and to refine the function of individual trichome genes.

Should a 31/62-day target be applicable to urinary stone patients with indwelling stents?

Objective:

Patients with urinary stone disease languish on waiting lists. They are often young and suffer morbidity and unemployment. Stone disease leads to sepsis, loss of renal units and even death. We aimed to assess the readmission rates and associated morbidity for patients with ureteric stents in situ secondary to stone disease.

Patients and methods:

Over 12 months 692 patients totalling 1114 admissions were admitted to our unit with a coded diagnosis of renal colic. Of the 692 individuals, 378 first presented as an emergency. The rest had elective first admissions.

Results:

Of the 378 emergency presentations, 78 were admitted between two and eight times. The total number of admissions for this group of 78 patients was 248. The average time interval was calculated from first emergency presentation to date of first elective treatment (52.3 days (range 2–281)) and from date of first emergency presentation to date of last treatment (63.6 days (range 2–281)). A total of 401 working days were lost.

Conclusion:

The management of patients with urinary stone disease needs serious reconsideration. We propose that patients with indwelling stents have a 31/62-day target similar to cancer patients due to the increased morbidity associated with loss of working days and the increased cost of readmissions to an overburdened health service.

Analysis of exhaled breath for diagnosing head and neck squamous cell carcinoma: a feasibility study

BACKGROUND

Squamous cell carcinoma of the head and neck (HNSCC) are wide-spread cancers that often lead to disfigurement and loss of important functions such as speech and ingestion. To date, HNSCC has no adequate method for early detection and screening.

METHODS

Exhaled breath samples were collected from 87 volunteers; 62 well-defined breath samples from 22 HNSCC patients (larynx and pharynx), 21 patients with benign tumours (larynx and pharynx) and 19 healthy controls were analysed in a dual approach: (i) chemical analysis using gas chromatography/mass spectrometry (GC-MS) and (ii) breath-print analysis using an array of nanomaterial-based sensors, combined with a statistical algorithm.

RESULTS

Gas chromatography/mass spectrometry identified ethanol, 2-propenenitrile and undecane as potential markers for HNSCC and/or benign tumours of the head and neck. The sensor-array-based breath-prints could clearly distinguish HNSCC both from benign tumours and from healthy states. Within the HNSCC group, patients could be classified according to tumour site and stage.

CONCLUSIONS

We have demonstrated the feasibility of a breath test for a specific, clinically interesting application: distinguishing HNSCC from tumour-free or benign tumour states, as well as for staging and locating HNSCC. The sensor array used here could form the basis for the development of an urgently needed non-invasive, cost-effective, fast and reliable point-of-care diagnostic/screening tool for HNSCC.

A comparative analysis of role attainment and impairment in binge-eating disorder and bulimia nervosa: results from the WHO World Mental Health Surveys

Background. Cross-national population data from the WHO World Mental Health surveys are used to compare role attainments and role impairments associated with binge-eating disorder (BED) and bulimia nervosa (BN). Methods. Community surveys assessed 23 000 adults across 12 countries for BED, BN and ten other DSM-IV mental disorders using the WHO Composite International Diagnostic Interview. Age-of-onset was assessed retrospectively. Ten physical disorders were assessed using standard conditions checklists. Analyses examined reciprocal time-lagged associations of eating disorders (EDs) with education, associations of early-onset (i.e., prior to completing education) EDs with subsequent adult role attainments and cross-sectional associations of current EDs with days of role impairment. Results. BED and BN predicted significantly increased education (females). Student status predicted increased risk of subsequent BED and BN (females). Early-onset BED predicted reduced odds of current (at time of interview) marriage (females) and reduced odds of current employment (males). Early-onset BN predicted increased odds of current work disability (females and males). Current BED and BN were both associated with significantly increased days of role impairment (females and males). Significant BED and BN effects on adult role attainments and impairments were explained by controls for comorbid disorders. Conclusions. Effects of BED on role attainments and impairments are comparable with those of BN. The most plausible interpretation of the fact that these associations are explained by comorbid disorders is that causal effects of EDs are mediated through secondary disorders. Controlled treatment effectiveness studies are needed to trace out long-term effects of BED-BN on secondary disorders.

[Pheochromocytoma: update on diagnosis and therapy]

Pheochromocytomas (P) are rare catecholamine producing neuroendocrine tumors originating from the chromaffin cells of the adrenal medulla or in 15 % of cases from extra adrenal chromaffin tissue and termed paragangliomas (PGL). Because of secretion of the catecholamines - adrenaline, noradrenaline and dopamine - the tumors are dangerous with a risk of life threating hypertensive crises. Measurements of plasma metanephrine, normetanephrine and methoxytyramine by liquid chromatography with tandem mass spectrometry provides the most accurate and precise method for biochemical diagnosis. Approximately 30-40 % of the tumors have a hereditary background due to mutations of 11 known susceptibility genes, with identification facilitated by targeted genetic testing according to clinical presentation. Apart from syndrome-dependent clinical stigmata, other hints to an underlying mutation can be provided by biochemical profiles of the catecholamine metabolites, tumor location, patient age and presence of metastatic disease. Surgery with minimal invasive procedures is the recommended therapeutic way after pretreatment with an alpha receptor blocking medication.

Elementary steps of the catalytic NO(x) reduction with NH3: cluster studies on reactant adsorption at vanadium oxide substrate

Extended cluster models together with density-functional theory are used to evaluate geometric, energetic, and electronic properties of different adsorbate species that can occur at a vanadium oxide surface where the selective catalytic reduction (SCR) of NO in the presence of ammonia proceeds. Here, we focus on atomic hydrogen, nitrogen, and oxygen, as well as molecular NO and NHx, x = 1, 4, adsorption at a model V2O5(010) surface. Binding sites, oxygen and vanadium, at both the perfect and reduced surface are considered where reduction is modeled by (sub-) surface oxygen vacancies. The reactants are found to bind overall more strongly at oxygen vacancy sites of the reduced surface where they stabilize in positions formerly occupied by the oxygen (substitutional adsorption) compared with weaker binding at the perfect surface. In particular, ammonia, which interacts only weakly with vanadium at the perfect surface, binds quite strongly near surface oxygen vacancies. In contrast, surface binding of the NH4 adsorbate species differs only little between the perfect and the reduced surface which is explained by the dominantly electrostatic nature of the adsorbate interaction. The theoretical results are consistent with experimental findings and confirm the importance of surface reduction for the reactant adsorption forming elementary steps of the SCR process.

A corticoid-sensitive cytokine release assay for monitoring stress-mediated immune modulation

The human immune system is orchestrated in a complex manner and protects the host against invading organisms and controls adequate immune responses to different antigen challenges in an endo-, auto- and paracrine-regulated fashion. The variety and intensity of immune responses are known to be dependent on stress-sensitive neural, humoral and metabolic pathways. The delayed-type hypersensitivity (DTH) skin test was a validated and standardized measure applied in clinical studies to monitor the integral function of cellular immune responses in vivo. The DTH skin test was, however, phased out in 2002. To obtain insight into the mechanisms of stress-sensitive immune reactions, we have developed an alternative in-vitro assay which allows the evaluation of antigen-dependent cellular immune responses triggered by T lymphocytes. The change in the concentration of proinflammatory cytokines in supernatant of the blood-antigen mixture is of particular interest to mirror the degree and adequacy of cellular immune responses. In this study we report that the proinflammatory cytokines interleukin (IL)-2, interferon (IFN)-γ and tumour necrosis factor (TNF)-α show a time-dependent increase upon ex-vivo bacterial, viral and fungal antigen stimulations. Furthermore, evidence is provided that this assay is sensitive to mirror stress hormone-mediated immune modulation in humans as shown either after hydrocortisone injection or after acute stress exposure during free fall in parabolic flight. This in-vitro test appears to be a suitable assay to sensitively mirror stress hormone-dependent inhibition of cellular immune responses in the human. Because of its standardization and relatively simple technical handling, it may also serve as an appropriate research tool in the field of psychoneuroendocrinology in clinical as in field studies.

A new cytokine release assay: a simple approach to monitor the immune status of HIV-infected patients

PURPOSE

To test a new assay based on an ex vivo cytokine release from whole blood for the monitoring of immune changes in human immunodeficiency virus (HIV)-infected patients.

METHODS

A pilot study of outpatients with HIV infection (n = 9) at a large academic hospital who were divided into three groups: HIV-infected patients on highly active antiretroviral therapy (HAART) with a CD4(+) cell count >350/μL (group I) or a CD4(+) cell count <350/μL (group II) and HIV-infected HAART-naïve subjects with a CD4(+) cell count >350/μL (group III). All groups were compared with healthy volunteers (n = 3). The ex vivo cytokine release assay was performed in a three-step process: (1) blood collection, (2) whole-blood ex vivo incubation over 48 h without or with a standard set of well-defined recall antigens as comparable to those used formerly in the skin delayed-type hypersensitivity (DTH) test, (3) cytokine determination from the assay supernatant.

RESULTS

Under stimulated conditions, untreated HIV-infected patients with a CD4(+) count >350/μL had similar interleukin-2 (IL-2) levels in the supernatant of the whole-blood incubation to HIV-infected patients on HAART with a low CD4(+) count. Both groups revealed lower IL-2 levels in the supernatant than HIV-infected patients on HAART and with a CD4(+) count >350/μL or healthy volunteers. The determination of interferon-γ and tumour necrosis factor-α in the supernatant showed a similar arrangement of cytokines between groups.

CONCLUSIONS

Our results suggest that this cytokine release assay could be a suitable tool to mirror the immunological responsiveness of patients with HIV infection in a gradual manner; further studies are required in order to assess its value in HAART monitoring.