Sleep Architecture and Sleep-Related Breathing Disorders of Seafarers on Board Merchant Ships: A Polysomnographic Pilot Field Study on the High Seas

As seafarers are assumed to have an increased risk profile for sleep-related breathing disorders, this cross-sectional observational study measured (a) the feasibility and quality of polysomnography (PSG) on board merchant ships, (b) sleep macro- and microarchitecture, (c) sleep-related breathing disorders, such as obstructive sleep apnea (OSA), using the apnea-hypopnea index (AHI), and (d) subjective and objective sleepiness using the Epworth Sleepiness Scale (ESS) and pupillometry. Measurements were carried out on two container ships and a bulk carrier. A total of 19 out of 73 male seafarers participated. The PSG's signal qualities and impedances were comparable to those in a sleep laboratory without unusual artifacts. Compared to the normal population, seafarers had a lower total sleep time, a shift of deep sleep phases in favor of light sleep phases as well as an increased arousal index. Additionally, 73.7% of the seafarers were diagnosed with at least mild OSA (AHI ≥ 5) and 15.8% with severe OSA (AHI ≥ 30). In general, seafarers slept in the supine position with a remarkable frequency of breathing cessations. A total of 61.1% of the seafarers had increased subjective daytime sleepiness (ESS > 5). Pupillometry results for objective sleepiness revealed a mean relative pupillary unrest index (rPUI) of 1.2 (SD 0.7) in both occupational groups. In addition, significantly poorer objective sleep quality was found among the watchkeepers. A need for action with regard to poor sleep quality and daytime sleepiness of seafarers on board is indicated. A slightly increased prevalence of OSA among seafarers is likely.

Health-related quality of life in oropharyngeal cancer survivors - a population-based study

OBJECTIVE

The aim of this study was to compare QoL of oropharyngeal cancer survivors who had received different treatments.

SUBJECTS AND METHODS

We contacted 954 survivors. Each survivor received the QoL questionnaires EORTC QLQ-C30 and EORTC QLQ-H&N35.

RESULTS

A total of 263 survivors completed the questionnaires (28% responses). Forty-five of them had undergone surgery, 20 had received definitive radiotherapy or chemo-radiotherapy, 85 surgery plus adjuvant radiotherapy, and 111 surgery plus adjuvant chemo-radiotherapy. Survivors who had received adjuvant radiotherapy and surgery reported significantly more problems with swallowing (B=13.43 [95% Confidence Interval (CI) 1.83-25.03]), senses (B=24,91 [CI 11.86-37.97]), eating (B=16.91 [CI 3.46-30.36]), dry mouth (B=26.42 [CI 12.17-40.67]), sticky saliva (B=22.37 [CI 6.23-38.50]) and nutritional supplements (B=18.59 [CI 0.62-36.56]) than those who had received surgery only. Survivors who had received adjuvant chemo-radiotherapy and surgery reported significantly many more problems with dry mouth (B=34.15 [CI 18.91-49.39]) and sticky saliva (B=22.90 [CI 5.65-40.16]), and fewer problems with physical functioning (B=-12.07 [CI 0.49-23-64]).

CONCLUSION

Survivors who participated in this survey and who had undergone surgery alone reported in some head- and neck-specific domains a better health-related quality of life than patients who had undergone multi-modal treatment or adjuvant radiotherapy.

Origin and Appearance of HITS Induced by Prosthetic Heart Valves: An in vitro Study

Patients with mechanical heart valve prostheses show significantly enhanced numbers of HITS detected by transcranial Doppler ultrasound. In order to assess the origin of HITS formation, an in vitro study was set out to quantify valve induced microemboli for mechanical and bioprosthetic valves under various circulatory conditions by means of Ultrasound-Doppler-Sonography. At the same time the influence of CO2 partial pressure on HITS rate vas investigated. It can be summarised that for mechanical heart valve prostheses a strong correlation exists between left ventricular dp/dtmax and the detected HITS rates. It was also demonstrated that a bioprosthesis generates significantly less HITS than a mechanical valve. The origin of HITS is gaseous since the tests were carried out using a cell-free filtered water-glycerol test fluid. The HITS rate could be increased by increasing the amount of dissolved gas within the test fluid. The results support the hypothesis that cavitation is the key factor in the appearance of gaseous microemboli at heart valve prostheses.

Abstract P1-12-03: Short term quality of life with epirubicin-fluorouracil-cyclophosphamid (FEC) and sequential epirubicin/cyclophosphamid-docetaxel (EC-DOC) chemotherapy in patients with primary breast cancer – Results from the prospective multi-center randomized Adebar trial

Background:

The grade of recommendation for adjuvant dose-dense chemotherapy in patients with high risk primary breast cancer is heterogeneous among international guidelines. Understanding the impact on quality of life (QOL) by adjuvant dose dense chemotherapy in comparison to standard adjuvant chemotherapy is thereby a crucial factor, especially if the benefit is potentially low. This study aims to assess the impact on QOL by adjuvant dose dense chemotherapy in the prospective randomized multi-center ADEBAR trial.

Methods:

QOL was assessed at baseline (t1), before cycle 4 FEC (Epirubicin 60mg/m2 i.v. d 1 + 8, 5-Fluoruracil 500mg/m2 i.v. d 1 + 8, Cyclophosphamide 75mg/m2 p.o. d 1–14, q4w x 6) and cycle 5 EC-DOC (Epirubicin 90mg/m2 plus Cyclophosphamide 600mg/m2 q3w x 4, sequentially followed by Docetaxel 100mg/m2 q3w x 4) (t2), 4 weeks after chemotherapy (t3), 6 weeks after radiation (t4) and 1 year after baseline (t5) using the European Organization for Research and Treatment for Cancer (EORTC) Quality of Life Core Questionnaire (QLQ-C30) and the Breast Cancer-Specific Module (QLQ-BR23). A multivariate mixed model was fitted to test for differences between the two treatment arms. Primary endpoint was global QOL, secondary endpoints physical functioning, nausea&vomiting, fatigue and systemic therapy side effects. A minimum clinically meaningful difference was considered to be 10 points.

Results:

1306 patients were recruited between 3/2002 and 5/2005 675 were assigned to the FEC and 688 to the EC-DOC arm. Compliance to QOL assessment was 74% at baseline and 58% four weeks after therapy, but dropped to 11% after one year follow up. After the beginning of treatment global QOL dropped in both arm by 3 to 4 points. In the EC-DOC arm QOL dropped further at t3 by 7 points and stayed stable in the FEC arm. 6 weeks after radiation QOL exceeded baseline in both arms by 6 to 8 points. The differences between treatment arms were strongest at t3 (54.1 vs. 49.7) but did not reach clinical relevance at any point in time. Physical functioning, nausea vomiting, fatigue and systemic therapy side effects followed with some minor exceptions similar patterns, but showed higher amplitudes.

Conclusion:

In conclusion we could not detect a statistically significant difference between the two treatment arms in QOL parameters, indicating that dose dense adjuvant chemotherapy did not impact QOL at a clinically relevant level compared to standard adjuvant chemotherapy.

Citation Format: Schwentner L, Harbeck N, Singer S, Eichler M, Rack B, Forstbauer H, Wischnik A, Scholz C, Fink V, Huober J, Friedl T, Weissenbacher T, Härtl K, Kiechle M, Janni W. Short term quality of life with epirubicin-fluorouracil-cyclophosphamid (FEC) and sequential epirubicin/cyclophosphamid-docetaxel (EC-DOC) chemotherapy in patients with primary breast cancer – Results from the prospective multi-center randomized Adebar trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-12-03.

[Pyogenic spondylodiscitis: therapy algorithm and a new classification for therapeutic decision-making]

The incidence of pyogenic spondylodiscitis is low but has been steadily increasing in recent years. To date there has been no consensus concerning selection of the appropriate treatment, management and strategies and the recommendations for an operative strategy are still a highly controversial issue. In the literature a few statements have been published concerning therapeutic decision-making in pyogenic spondylodiscitis. The classification given in this article is based on clinical experience and retrospective data analysis considering the degree of segmental bony destruction, grade of kyphosis and instability, epidural involvement of the disease and neurological deficits, which are pivotal for therapeutic decision-making. The therapeutic procedure can be defined based on this classification.

Formation and photocatalytic decomposition of a pellicle on anatase surfaces

The acquired dental pellicle plays a critical role in the adhesion and detachment of dental plaque bacteria. It has been reported that titanium dioxide biomaterials decompose single-protein films by photocatalysis. However, it is not known whether this can also be achieved with complex structured pellicle films. This in vitro study investigated in real-time the formation and photocatalytic decomposition of human pellicle at anatase-saliva interfaces. Nanostructured polycrystalline anatase layers were deposited on titanium-coated quartz crystals by magnetron-sputtering, serving as a model for titanium implant surfaces. The quartz crystals were used as acoustic sensors in a quartz-crystal microbalance (QCM) system with dissipation. In situ UV irradiation of pellicle-covered anatase caused a statistically significant decrease of the adsorbed salivary mass. In contrast, photocatalytic decomposition of pellicle could not be observed on reference titanium surfaces. Wettability characterization revealed superhydrophilicity of anatase upon UV irradiation, whereas titanium was unaffected. XPS measurements provide further information concerning the decomposition of the salivary films. The results suggest that the photocatalytic activity of polycrystalline anatase-modified biomaterial surfaces is able to decompose complex structured macromolecular pellicle films. Therefore, this study opens the way to surface modifications supporting therapeutic approaches of biofilm removal.

Multifunctional nature of UV-irradiated nanocrystalline anatase thin films for biomedical applications

Anatase is known to decompose organic material by photocatalysis and to enhance surface wettability once irradiated by ultraviolet (UV) light. In this study, pulse magnetron-sputtered anatase thin films were investigated for their suitability with respect to specific biomedical applications, namely superhydrophilic and biofilm degrading implant surfaces. UV-induced hydrophilicity was quantified by static and dynamic contact angle analysis. Photocatalytic protein decomposition was analyzed by quartz crystal microbalance with dissipation. The surfaces were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. The radical formation on anatase, responsible for photocatalytic effects, was analyzed by electron spin resonance spectroscopy. Results have shown that the nanocrystalline anatase films, in contrast to reference titanium surfaces, were sensitive to UV irradiation and showed rapid switching towards superhydrophilicity. The observed decrease in carbon adsorbents and the increase in the fraction of surface hydroxyl groups upon UV irradiation might contribute to this hydrophilic behavior. UV irradiation of anatase pre-conditioned with albumin protein layers induces the photocatalytic decomposition of these model biofilms. The observed degradation is mainly caused by hydroxyl radicals. It is concluded that nanocrystalline anatase films offer different functions at implant interfaces, e.g. bedside hydrophilization of anatase-coated implants for improved osseointegration or the in situ decomposition of conditioning films forming the basal layer of biofilms in the oral cavity.

A general strategy for site-specific double labeling of globular proteins for kinetic FRET studies

Site-directed mutagenesis provides a straightforward means of creating specific targets for chemical modifications of proteins. This capability enhanced the applications of spectroscopic methods adapted for addressing specific structural questions such as the characterization of partially folded and transient intermediate structures of globular proteins. Some applications such as the steady state or time-resolved fluorescence resonance energy transfer (FRET) detection of the kinetics of protein folding require relatively large quantities (approximately 10-100 mg) of site-specific doubly labeled protein samples. Engineered cysteine residues are common targets for labeling of proteins. The challenge here is to develop methods for selective modification of one of two reactive sulfhydryl groups in a protein molecule. A general systematic procedure for selective labeling of each of two cysteine residues in a protein molecule was developed, using Escherichia coli adenylate kinase (AKe) as a model protein. Potential sites for insertion of cysteine residues were selected by examination of the crystal structure of the protein. A series of single-cysteine mutants was prepared, and the rates of the reaction of each engineered cysteine residue with a reference reagent [5,5'-dithiobis(2-nitrobenzoic acid) (DTNB)] were determined. Two-cysteine mutants were prepared by selection of pairs of sites for which the ratio of this reaction rate constant was high (>80). The conditions for the selective labeling reaction were optimized. In a first cycle of labeling, the more reactive cysteine residue was labeled with a fluorescent probe (donor). The second probe was attached to the less reactive site under unfolding conditions in the second cycle of labeling. The doubly and singly labeled mutants retained full enzymatic activity and the capacity for a reversible folding-unfolding transition. High yields (70-90%) of the preparation of the pure, site-specific doubly labeled AK mutant were obtained. The procedure described herein is a general outline of procedures, which can meet the double challenge of both site specificity and large-scale preparation of doubly labeled proteins.

Measurement of parenting self-efficacy and outcome expectancy related to discussions about sex

The purpose of this study was to evaluate the psychometric properties of two scales--one to measure the self-efficacy of parents to discuss sexual health issues with their adolescents and the other to measure parents' outcome expectancy associated with such discussions. Understanding how parents feel about their confidence in talking with their children about important sexual health issues and the outcomes they expect as a result of such discussions can be useful in guiding both the development and refinement of educational programs to promote parent-child discussions. The responses of 491 mothers who participated in an HIV prevention intervention with their adolescents were used for the present analysis. Mothers ranged in age from 25 to 68 years with a mean of 37.9 years (SD = 6.9). Of mother participants, 33% were married, 96.7% were African American, and 89.2% had completed high school. Their adolescents ranged in age from 11 to 14 years, and 61.5% were male. Assessment of reliability for both scales showed that internal consistency reliability was acceptable for the total scales as well as three of the five subscales. With the exception of one item on the outcome expectancy scale, the inter-item correlations, the mean inter-item correlations, and the item-to-total correlations meet the standard criteria for scale development for both scales. Factor analysis was used to identify the underlying structure of the scales, and hypothesis testing was used to assess construct validity. The results of these analyses provide support for the construct validity of the scales.

Origin and appearance of HITS induced by prosthetic heart valves: an in vitro study

Patients with mechanical heart valve prostheses show significantly enhanced numbers of HITS detected by transcranial Doppler ultrasound. In order to assess the origin of HITS formation, an in vitro study was set out to quantify valve induced microemboli for mechanical and bioprosthetic valves under various circulatory conditions by means of Ultrasound-Doppler-Sonography. At the same time the influence of CO2 partial pressure on HITS rate vas investigated. It can be summarised that for mechanical heart valve prostheses a strong correlation exists between left ventricular dp/dtmax and the detected HITS rates. It was also demonstrated that a bioprosthesis generates significantly less HITS than a mechanical valve. The origin of HITS is gaseous since the tests were carried out using a cell-free filtered water-glycerol test fluid. The HITS rate could be increased by increasing the amount of dissolved gas within the test fluid. The results support the hypothesis that cavitation is the key factor in the appearance of gaseous microemboli at heart valve prostheses.

Can vortices in the flow across mechanical heart valves contribute to cavitation?

Cavitation in mechanical heart valves is traditionally attributed to the hammer effect and to squeeze and clearance flow occurring at the moment of valve closure. In the present study, an additional factor is considered--the contribution of vortex flow. Using a computational fluid dynamics analysis of a 2D model of a tilting disk mitral valve, we demonstrate that vortices may form in the vicinity of the inflow side of the valve. These vortices roll up from shear layers emanating from the valve tips during regurgitation. A significant decrease in the pressure at the centre of the vortices is found. The contribution of the vortex to the total pressure drop at the instant of closure is of the order of 70 mmHg. Adding this figure to the other pressure drop sources that reach 670 mmHg, it might be that this is the deciding factor that causes the drop in blood pressure below vapour pressure. The total pressure drop near the upper tip (750 mmHg) is larger than near the lower tip (670 mmHg), indicating a preferential location for cavitation inception, in agreement with existing experimental findings.

A library of atmospheric pressure ionization daughter ion mass spectra based on wideband excitation in an ion trap mass spectrometer

A searchable library of MS/MS spectra obtained using a quadrupole ion trap mass spectrometer and electrospray or atmospheric pressure chemical ionization is presented. The application of wideband excitation (activation) and normalized collision energy leads to highly reproducible mass spectra which are searched using the NIST algorithm. Flow injection and LC/MS/MS applications of this powerful technique in the biomedical (diastereoisomeric steroids, morphine glucuronides, isovalerylcarnitine) and environmental (pirimicarb and desmethyl-pirimicarb) areas are described.

Identification of synaptic connections in neural ensembles by graphical models

A method for the identification of direct synaptic connections in a larger neural net is presented. It is based on a conditional correlation graph for multivariate point processes. The connections are identified via the partial spectral coherence of two neurons, given all others. It is shown how these coherences can be calculated by inversion of the spectral density matrix. In simulations with GENESIS, we discuss the relevance of the method for identifying different neural ensembles including an excitatory feedback loop and networks with lateral inhibitions.

Recognition of laparoscopic bile duct injuries by intraoperative ultrasonography

BACKGROUND

The purpose of this study was to investigate the possibility of detecting bile duct injuries using laparoscopic intraoperative ultrasound (LIOU).

METHODS

Fifty bile duct injuries were created using laparoscopic techniques in ten farmer pigs. The lesions created were: (1) partial occlusion, (2) complete occlusion (1 clip), (3) complete occlusion (2 clips), (4) transection between clips, (5) excision between clips.

RESULTS

All injuries were easily visualized using LIOU. The relation of clips impinging upon or occluding the bile duct was readily visualized on LIOU in all cases. In some cases it was difficult to distinguish between partial and complete occlusion. It was also difficult to distinguish between transection and excision due to retraction of the severed bile duct.

CONCLUSIONS

In cases of iatrogenic occlusion of the bile duct involving hemoclips (including transection or excision between clips), LIOU is a potentially useful modality that may allow earlier recognition and repair. Further studies are needed to evaluate the efficacy of LIOU in detection of bile duct injuries that do not involve hemoclips.

In vitro testing of heart valve wear outside of the manufacturers laboratory--requirements and controversies

BACKGROUND AND AIM OF THE STUDY

Currently, various national and international Standards regulate in vitro and in vivo testing as well as the clinical evaluation of heart valve prostheses. This study concentrates on a single aspect of these protocols: accelerated wear and fatigue testing.

METHODS

The differences in the above Standards were appraised and an experimental study was designed to assess the validity of Standard testing conditions with respect to in vivo relevance. An instrumented BSCC tilting disc valve was tested in two different types of fatigue testers and in a separate study in a sheep model.

RESULTS

By comparing the obtained results it could be clearly demonstrated that under the current Standard conditions (ISO, CEN, FDA) actual in vivo impact loading cannot be reproduced. Also, the two compared test devices, though operating under the same Standard conditions, generated totally different loading conditions on the test valve.

CONCLUSIONS

Based on these findings it is suggested that the actual loading conditions of each valve type should be measured either in vivo in animal models or within a circulatory mock loop which provides physiologic loading conditions, and the test conditions for accelerated wear and fatigue testing should be modified accordingly. Cavitation effects which can be assumed to be associated with high frequency wear testing is another important issue which has to be addressed in future amendments to the Test Standards.

The effect of left ventricular dP/dt on the in vitro dynamics of the Björk-Shiley Convexo-Concave mitral valve

Left ventricular (LV) dP/dt is considered an important hemodynamic factor influencing the dynamics of mechanical heart valve prostheses. LV dP/dt is dependent on patient factors including age, cardiac activity, health, and medication. The objective of this study was to determine the effect of LV dP/dt on the closing dynamics of mechanical heart valve prostheses in the mitral position. Eight instrumented 29 mm Björk-Shiley Convexo-Concave (BSCC) heart valves were tested in the pulse duplicator of the Helmholtz Institute. The valves had miniature strain gages mounted at the base of the outlet strut to measure impact loads at closure. Closing velocities were measured with a "light gate" device which was triggered by the closing leaflet. Physiologic pressure and flow waveforms were generated by a computer-controlled hydraulic drive unit. LV dP/dt was varied from 500 to 4000 mmHg/s simulating a wide range of physiologic conditions. It was found that the closing velocity was almost linearly related to LV dP/dt. At 4000 mmHg/s, closing velocities ranged from 1.5 to 2.0 m/s. Impact loads increased monotonically with LV dP/dt and closing velocity. In some valves, impact loads reached 2800 g at LV dP/dt of 4000 mmHg/s, and closing velocities of 2.0 m/s.

[What is the contribution of yeast genetics to tumor biology and tumor diagnosis?]

This short review article discusses methods and results of oncogene research in yeast. Current knowledge of the sequence, expression and biological function of ras-homologous genes of the yeast Saccharomyces cerevisiae is presented, as well as the implications of these findings for oncogene research in mammals. We review recent examples of highly conserved eukaryotic genes involved in growth control and mitosis control, including recent work from our own laboratories.

AIDS cases with no identified risk: artifact or reality? The Connecticut example

Connecticut's 66 AIDS cases initially reported with no identified risks (NIRS) were reviewed and intensively investigated. Investigation resulted in reclassification of 45 cases (68.2%) to categories of known risk; one case (1.5%) was misdiagnosed as AIDS. Twenty cases (30.3%) remain NIRS because no risk could be established at this time. Evidence that NIRS represent reporting artifact, rather than unknown or new modes of transmission, was found. (1) NIRS are cases for which information on sexual behavior is highly sensitive or difficult to obtain. After investigation, 72% of reclassified Connecticut NIRS were determined to have risks related to sexual transmission. (2) The percentage of NIRS fluctuates according to reporting source and method of investigation. Within Connecticut, major reporting sources vary from a high of 15% to a low of 0% NIRS among their cases. The most effective method for establishing risks was to obtain information from reporting sources.