Genomic characterisation of hormone receptor-positive breast cancer arising in very young women

BACKGROUND

Very young premenopausal women diagnosed with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+HER2-) early breast cancer (EBC) have higher rates of recurrence and death for reasons that remain largely unexplained.

PATIENTS AND METHODS

Genomic sequencing was applied to HR+HER2- tumours from patients enrolled in the Suppression of Ovarian Function Trial (SOFT) to determine genomic drivers that are enriched in young premenopausal women. Genomic alterations were characterised using next-generation sequencing from a subset of 1276 patients (deep targeted sequencing, n = 1258; whole-exome sequencing in a young-age, case-control subsample, n = 82). We defined copy number (CN) subgroups and assessed for features suggestive of homologous recombination deficiency (HRD). Genomic alteration frequencies were compared between young premenopausal women (<40 years) and older premenopausal women (≥40 years), and assessed for associations with distant recurrence-free interval (DRFI) and overall survival (OS).

RESULTS

Younger women (<40 years, n = 359) compared with older women (≥40 years, n = 917) had significantly higher frequencies of mutations in GATA3 (19% versus 16%) and CN amplifications (CNAs) (47% versus 26%), but significantly lower frequencies of mutations in PIK3CA (32% versus 47%), CDH1 (3% versus 9%), and MAP3K1 (7% versus 12%). Additionally, they had significantly higher frequencies of features suggestive of HRD (27% versus 21%) and a higher proportion of PIK3CA mutations with concurrent CNAs (23% versus 11%). Genomic features suggestive of HRD, PIK3CA mutations with CNAs, and CNAs were associated with significantly worse DRFI and OS compared with those without these features. These poor prognostic features were enriched in younger patients: present in 72% of patients aged <35 years, 54% aged 35-39 years, and 40% aged ≥40 years. Poor prognostic features [n = 584 (46%)] versus none [n = 692 (54%)] had an 8-year DRFI of 84% versus 94% and OS of 88% versus 96%. Younger women (<40 years) had the poorest outcomes: 8-year DRFI 74% versus 85% and OS 80% versus 93%, respectively.

CONCLUSION

These results provide insights into genomic alterations that are enriched in young women with HR+HER2- EBC, provide rationale for genomic subgrouping, and highlight priority molecular targets for future clinical trials.

Immune checkpoint inhibition and targeted therapy for melanoma: A patient‐oriented cross‐sectional comparative multicenter study

BACKGROUND

Choosing the adequate systemic treatment for melanoma is driven by clinical parameters and personal preferences.

OBJECTIVE

Evaluation of the impact of disease and treatment on the daily life of patients receiving systemic therapy for melanoma.

METHODS

A German-wide, cross-sectional comparative study was conducted at 13 specialized skin cancer centres from 08/2020 to 03/2021. A questionnaire was distributed to assess patients' perception of disease and symptoms, the impact of their current treatment on quality of life (QOL) and activities, adverse events (AEs), therapeutic visits, as well as believe in and satisfaction with their current systemic melanoma treatment. Patient-reported outcomes (PROs) were rated on a continuous numerical rating scale or selected from a given list.

RESULTS

Four hundred and fourteen patients with systemic melanoma therapy were included. 359 (87%) received immune checkpoint inhibition (ICI) and 55 (13%) targeted therapy (TT). About 1/3 of patients were adjuvantly treated, the remaining because of unresectable/metastatic melanoma. In subgroup analyses, only in the adjuvant setting, TT patients reported a significant decrease in their treatment associated QOL compared to patients with ICI (p = 0.02). Patients with TT were 1.9 times more likely to report AEs than patients with ICI, a difference being significant just for the adjuvant setting (p = 0.01). ICI treatment intervals differed significantly between adjuvant and unresectable/metastatic setting (p = 0.04), though all patients, regardless of their specific ICI drug, evaluated their treatment frequency as adequate. TT patients with dabrafenib/trametinib (n = 37) or encorafenib/binimetinib (n = 15) did not differ regarding the strain of daily pill intake. Patients older than 63 years rated various PROs better than younger patients.

CONCLUSIONS

Patients evaluated their treatment mainly positively. ICI might be preferred over TT regarding QOL and patient-reported AEs in the adjuvant setting. Older melanoma patients appeared to be less impacted by their disease and more satisfied with their treatment.

Continuous versus intermittent extended adjuvant letrozole for breast cancer: final results of randomized phase III SOLE (Study of Letrozole Extension) and SOLE Estrogen Substudy

BACKGROUND

Late recurrences in postmenopausal women with hormone receptor-positive breast cancers remain an important challenge. Avoidance or delayed development of resistance represents the main objective in extended endocrine therapy (ET). In animal models, resistance was reversed with restoration of circulating estrogen levels during interruption of letrozole treatment. This phase III, randomized, open-label Study of Letrozole Extension (SOLE) studied the effect of extended intermittent letrozole treatment in comparison with continuous letrozole. In parallel, the SOLE estrogen substudy (SOLE-EST) analyzed the levels of estrogen during the interruption of treatment.

PATIENTS AND METHODS

SOLE enrolled 4884 postmenopausal women with hormone receptor-positive, lymph node-positive, operable breast cancer between December 2007 and October 2012 and among them, 104 patients were enrolled in SOLE-EST. They must have undergone local treatment and have completed 4-6 years of adjuvant ET. Patients were randomized between continuous letrozole (2.5 mg/day orally for 5 years) and intermittent letrozole treatment (2.5 mg/day for 9 months followed by a 3-month interruption in years 1-4 and then 2.5 mg/day during all of year 5).

RESULTS

Intention-to-treat population included 4851 women in SOLE (n = 2425 in the intermittent and n = 2426 in the continuous letrozole groups) and 103 women in SOLE-EST (n = 78 in the intermittent and n = 25 in the continuous letrozole groups). After a median follow-up of 84 months, 7-year disease-free survival (DFS) was 81.4% in the intermittent group and 81.5% in the continuous group (hazard ratio: 1.03, 95% confidence interval: 0.91-1.17). Reported adverse events were similar in both groups. Circulating estrogen recovery was demonstrated within 6 weeks after the stop of letrozole treatment.

CONCLUSIONS

Extended adjuvant ET by intermittent administration of letrozole did not improve DFS compared with continuous use, despite the recovery of circulating estrogen levels. The similar DFS coupled with previously reported quality-of-life advantages suggest intermittent extended treatment is a valid option for patients who require or prefer a treatment interruption.

Data fusion and smoothing for probabilistic tracking of viral structures in fluorescence microscopy images

Automatic tracking of viral structures displayed as small spots in fluorescence microscopy images is an important task to determine quantitative information about cellular processes. We introduce a novel probabilistic approach for tracking multiple particles based on multi-sensor data fusion and Bayesian smoothing methods. The approach exploits multiple measurements as in a particle filter, both detection-based measurements and prediction-based measurements from a Kalman filter using probabilistic data association with elliptical sampling. Compared to previous probabilistic tracking methods, our approach exploits separate uncertainties for the detection-based and prediction-based measurements, and integrates them by a sequential multi-sensor data fusion method. In addition, information from both past and future time points is taken into account by a Bayesian smoothing method in conjunction with the covariance intersection algorithm for data fusion. Also, motion information based on displacements is used to improve correspondence finding. Our approach has been evaluated on data of the Particle Tracking Challenge and yielded state-of-the-art results or outperformed previous approaches. We also applied our approach to challenging time-lapse fluorescence microscopy data of human immunodeficiency virus type 1 and hepatitis C virus proteins acquired with different types of microscopes and spatial-temporal resolutions. It turned out, that our approach outperforms existing methods.

Scavenging of Dickkopf-1 by macromer-based biomaterials covalently decorated with sulfated hyaluronan displays pro-osteogenic effects

Dickkopf-1 (DKK1), a Wnt inhibitor secreted by bone marrow stromal cells (MSC), is known to play an important role in long-term non-union bone fracture defects and glucocorticoid induced osteoporosis. Mitigating its effects in early bone defects could improve osteogenesis and bone defect healing. Here, we applied a biomaterial strategy to deplete a defect environment from DKK1 by scavenging the protein via a macromer-based biomaterial covalently decorated with sulfated hyaluronan (sHA3). The material consisted of cross-copolymerized three-armed macromers with a small anchor molecule. Using the glycidyl anchor, polyetheramine (ED900) could be grafted to the material to which sHA3 was efficiently coupled in a separate step. For thorough investigation of material modification, flat material surfaces were generated by fabricating them on glass discs. The binding capability of sHA3 for DKK1 was demonstrated in this study by surface plasmon resonance measurements. Furthermore, the surfaces demonstrated the ability to scavenge and inactivate pathologic amounts of DKK1 from complex media. In a combinatory approach with Wnt3a, we were able to demonstrate that DKK1 is the preferred binding partner of our sHA3-functionalized surfaces. We validated our findings in a complex in vitro setting of differentiating SaOS-2 cells and primary hMSC. Here, endogenous DKK-1 was scavenged resulting in increased osteogenic differentiation indicating that this is a consistent biological effect irrespective of the model system used. Our study provides insights in the mechanisms and efficiency of sHA3 surface functionalization for DKK1 scavenging, which may be used in a clinical context in the future.

Magnetic vortex nucleation and annihilation in bi-stable ultra-small ferromagnetic particles

Vortex-mediated magnetization reversal in individual ultra-small (∼100 nm) ferromagnetic particles at low temperatures is studied by nanoSQUID magnetometry. At zero applied bias field, the flux-closure magnetic state (vortex) and the quasi uniform configuration are bi-stable. This stems from the extremely small size of the nanoparticles that lies very close to the limit of single-domain formation. The analysis of the temperature-dependent (from 0.3 to 70 K) hysteresis of the magnetization allows us to infer the nature of the ground state magnetization configuration. The latter corresponds to a vortex state as also confirmed by electron holography experiments. Based on the simultaneous analysis of the vortex nucleation and annihilation data, we estimate the magnitude of the energy barriers separating the quasi single-domain and the vortex state and their field dependence. For this purpose, we use a modified power-law scaling of the energy barriers as a function of the applied bias field. These studies are essential to test the thermal and temporal stability of flux-closure states stabilized in ultra-small ferromagnets.

Determination of Total Taurine in Pet Foods by Liquid Chromatography of the Dansyl Derivative: Collaborative Study

A liquid chromatographic (LC) method for the determination of total taurine in pet foods was evaluated in a collaborative study. Ten laboratories assayed 6 blind duplicate pairs of wet and dry pet foods. The taurine in the 6 sample pairs ranged from low (170 mg/kg) to high (2250 mg/kg) concentrations as is. Collaborators also assayed a sample of known taurine concentration for familiarization purposes. Samples were hydrolyzed to release bound taurine, which was subsequently converted to the dansyl derivative and quantitated by gradient-elution LC with fluorescence detection. Repeatability relative standard deviations, RSDr, ranged from 3.2 to 10.0%; reproducibility relative standard deviations, RSDR, ranged from 6.1 to 16.1%. The method has been adopted Official First Action status by AOAC INTERNATIONAL.

Toward genome editing in X-linked RP-development of a mouse model with specific treatment relevant features

Genome editing represents a powerful tool to treat inherited disorders. Highly specific endonucleases induce a DNA double strand break near the mutant site, which is subsequently repaired by cellular DNA repair mechanisms that involve the presence of a wild type template DNA. In vivo applications of this strategy are still rare, in part due to the absence of appropriate animal models carrying human disease mutations and knowledge of the efficient targeting of endonucleases. Here we report the generation and characterization of a new mouse model for X-linked retinitis pigmentosa (XLRP) carrying a point mutation in the mutational hotspot exon ORF15 of the RPGR gene as well as a recognition site for the homing endonuclease I-SceI. Presence of the genomic modifications was verified at the RNA and protein levels. The mutant protein was observed at low levels. Optical coherence tomography studies revealed a slowly progressive retinal degeneration with photoreceptor loss starting at 9 months of age, paralleling the onset of functional deficits as seen in the electroretinogram. Early changes to the outer retinal bands can be used as biomarker during treatment applications. We further show for the first time efficient targeting using the I-SceI enzyme at the genomic locus in a proof of concept in photoreceptors following adeno-associated virus mediated gene transfer in vivo. Taken together, our studies not only provide a human-XLRP disease model but also act as a platform to design genome editing technology for retinal degenerative diseases using the currently available endonucleases.

NanoSQUID Magnetometry on Individual As-grown and Annealed Co Nanowires at Variable Temperature

Performing magnetization studies on individual nanoparticles is a highly demanding task, especially when measurements need to be carried out under large sweeping magnetic fields or variable temperature. Yet, characterization under varying ambient conditions is paramount in order to fully understand the magnetic behavior of these objects, e.g., the formation of nonuniform states or the mechanisms leading to magnetization reversal and thermal stability. This, in turn, is necessary for the integration of magnetic nanoparticles and nanowires into useful devices, e.g., spin-valves, racetrack memories, or magnetic tip probes. Here, we show that nanosuperconducting quantum interference devices based on high critical temperature superconductors are particularly well suited for this task. We have successfully characterized a number of individual Co nanowires grown through focused electron beam induced deposition and subsequently annealed at different temperatures. Magnetization measurements performed under sweeping magnetic fields (up to ∼100 mT) and variable temperature (1.4-80 K) underscore the intrinsic structural and chemical differences between these nanowires. These point to significant changes in the crystalline structure and the resulting effective magnetic anisotropy of the nanowires, and to the nucleation and subsequent vanishing of antiferromagnetic species within the nanowires annealed at different temperatures.

Optimized breath detection algorithm in electrical impedance tomography

OBJECTIVE

This paper defines a method for optimizing the breath delineation algorithms used in electrical impedance tomography (EIT). In lung EIT the identification of the breath phases is central for generating tidal impedance variation images, subsequent data analysis and clinical evaluation. The optimisation of these algorithms is particularly important in neonatal care since the existing breath detectors developed for adults may give insufficient reliability in neonates due to their very irregular breathing pattern.

APPROACH

Our approach is generic in the sense that it relies on the definition of a gold standard and the associated definition of detector sensitivity and specificity, an optimisation criterion and a set of detector parameters to be investigated. The gold standard has been defined by 11 clinicians with previous experience with EIT and the performance of our approach is described and validated using a neonatal EIT dataset acquired within the EU-funded CRADL project.

MAIN RESULTS

Three different algorithms are proposed that improve the breath detector performance by adding conditions on (1) maximum tidal breath rate obtained from zero-crossings of the EIT breathing signal, (2) minimum tidal impedance amplitude and (3) minimum tidal breath rate obtained from time-frequency analysis. As a baseline a zero-crossing algorithm has been used with some default parameters based on the Swisstom EIT device.

SIGNIFICANCE

Based on the gold standard, the most crucial parameters of the proposed algorithms are optimised by using a simple exhaustive search and a weighted metric defined in connection with the receiver operating characterics. This provides a practical way to achieve any desirable trade-off between the sensitivity and the specificity of the detectors.

Automatic deformable registration of histological slides to μCT volume data

Localizing a histological section in the three-dimensional dataset of a different imaging modality is a challenging 2D-3D registration problem. In the literature, several approaches have been proposed to solve this problem; however, they cannot be considered as fully automatic. Recently, we developed an automatic algorithm that could successfully find the position of a histological section in a micro computed tomography (μCT) volume. For the majority of the datasets, the result of localization corresponded to the manual results. However, for some datasets, the matching μCT slice was off the ground-truth position. Furthermore, elastic distortions, due to histological preparation, could not be accounted for in this framework. In the current study, we introduce two optimization frameworks based on normalized mutual information, which enabled us to accurately register histology slides to volume data. The rigid approach allocated 81 % of histological sections with a median position error of 8.4 μm in jaw bone datasets, and the deformable approach improved registration by 33 μm with respect to the median distance error for four histological slides in the cerebellum dataset.

Abstract P5-18-01: Extended continuous vs intermittent adjuvant letrozole in postmenopausal women with lymph node-positive, early breast cancer (IBCSG 37-05/BIG 1-07 SOLE): Impact on patient-reported symptoms and quality of life

Background: SOLE efficacy results presented at ASCO 2017 showed that extended intermittent vs continuous letrozole for 5 years did not improve disease-free survival in postmenopausal women who had received 4-6 years of adjuvant endocrine therapy for hormone-receptor positive (HR+), lymph-node positive breast cancer. Previous studies showed that the burden by symptoms related to endocrine therapy can be substantial. Even if symptoms improve during the treatment course, extending treatment implies continuation of symptoms. We compared differences in patient-reported symptoms (PRS) and quality of life (QoL) between extended continuous and intermittent letrozole over the first two years of trial treatment.

Methods: From Nov 2007 to Dec 2010, 956 postmenopausal women who were disease-free following 4-6 years of prior adjuvant endocrine therapy for HR+, node-positive breast cancer were enrolled in the QoL substudy of the randomized phase III trial SOLE at selected centers. Patients receive extended continuous letrozole (2.5 mg daily) for 5 years or intermittent letrozole, taken for the first 9 months of years 1-4, and 12 months in year 5. 955 patients completed the 18-item Breast Cancer Prevention Trial (BCPT) Symptom Scales and further symptom-specific and global QoL indicators at baseline, and at 6, 12, 18 and 24 months after randomization. Differences in change of PRS and QoL from baseline between the two administration schedules were tested at 12 and 24 months for 8 symptom scales, 4 additional symptom and 4 global QoL indicators using mixed models with repeated measures.

Results: Small changes in PRS and QoL scores were observed between baseline and 12 months after randomization, i.e. at the end of the first treatment-free interval in the intermittent arm. These changes showed a consistent pattern of greater worsening for patients receiving continuous compared to patients receiving intermittent letrozole. Patients receiving continuous letrozole reported a significantly greater worsening in vaginal problems (p&lt;.02), musculoskeletal pain (p&lt;.03), sleep disturbance (p&lt;.01), physical wellbeing (p&lt;.01) and mood (p&lt;.03). At 24 months (after 2nd treatment-free interval) patients with intermittent letrozole reported a greater improvement in hot flushes (p&lt;.03) than those with continuous letrozole. Changes in the other outcomes did not significantly differ between arms at 24 months.

Conclusion: Although changes in PRS and QoL were small, there was a consistent pattern favoring the intermittent arm. For several symptoms and global QoL indicators, significantly less worsening was observed with the intermittent administration, mainly during the first year of extended treatment, due to small improvements during the treatment-free interval. Froma QoL perspective, women who suffer from endocrine side-effects in the extended setting may benefit from an intermittent administration.

Citation Format: Ribi K, Luo W, Colleoni M, Karlsson P, Chirgwin J, Aebi S, Jerusalem G, Neven P, Di Lauro V, Gomez HL, Ruhstaller T, Abdi E, Di Leo A, Müller B, Maibach R, Gelber RD, Goldhirsch A, Coates AS, Regan MM, Bernhard J. Extended continuous vs intermittent adjuvant letrozole in postmenopausal women with lymph node-positive, early breast cancer (IBCSG 37-05/BIG 1-07 SOLE): Impact on patient-reported symptoms and quality of life [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-18-01.

Eine Methode zur kombinierten Scatter- und Schwächungskorrektur ohne Transmissionsmessung für die Myokard-SPECT mit 99mTc- Verbindungen

Ziel: Für eine Doppelkopf-SPECT-Kamera wird eine Strategie zur Bestimmung der Schwächungsverteilung aus den Zählraten der Rückwärtsstreuung von 99mTc vorgestellt. Ziel war die Gewinnung von segmentierten und normierten Schwächungsbildern mit den Strukturen Lunge und Fett- bzw. Muskelgewebe, so daß nach dem Verfahren von Chang eine Schwächungskorrektur vorgenommen werden kann. Methoden: In den akquirierten Winkelprojektionen wurden sowohl Näherungen für die Schwächung als auch eine Scatterkorrektur nach dem Verfahren von Ogawa et al. berechnet, wobei die Akquisition simultan in drei getrennten 99mTc-Energiefenstern zur Ermittlung von Emissions- und Streustrahlung erfolgt. Anhand von Phantommessungen und Patientenmessungen wurde die Güte der Schwächungsnäherungen und der Schwächungskorrektur untersucht und die beste Wahl für alle auftretenden Parameter zur Schwächungskorrektur ermittelt. Ergebnisse: Das Verfahren stellt eine gute Näherung zur Korrektur der Photonenschwächung und der Streustrahlung dar. Eine Plausibilitäts-kontrolle an Phantom- und beispielhaften Patientenstudien belegte vorläufig auch die klinische Brauchbarkeit. Bei normaler Perfusion wurde die Verteilung homogenisiert, Defekte erschienen klarer. Probleme entstehen bei hohen Non-target-Aktivitäten, z. B. in der Gallenblase, und bei zu geringer Zählrate. Schlußfolgerung: Eine für die 99mTc MIBI-SPECT des Myokards sinnvolle und brauchbare Korrektur von Schwächung und Streuung ist auch ohne zusätzliche Transmissionseinrichtung möglich.

Pretherapeutic dosimetry before 131I therapy of benign thyroid disease

Aim: To compare uptake measurements and different methods for the pretherapeutic determination of the effective thyroidal 131I half life (Teff) to the results of posttherapeutic dosimetric measurements. Patients, methods: Retrospective study of 1538 patients who received their first RIT in our department for autonomous thyroid nodules (ATN), autonomous multinodular goiter (AMG) or Graves' disease (GD) between November 1999 and January 2011. Pretherapeutic measurements were performed at any combination of 24 h, 48 h and 6 days after 131I administration. Post-therapy dosimetric measurements were performed in 12 h intervals until discharge. Teff was determined through monoexponential curve fitting. Results: Pretherapeutic Teff values based on measurements at 24 h and 48 h, 24 h and 6 d, 48 h and 6 d as well as on day 24 h, 48 h and 6 d yielded implausible (< 2 d or > 8 d) values for Teff, in 60.4%, 25.7%, 29.1 and 21.4% of available calculations, respectively. The plausible results showed significant, clinically relevant and sometimes considerable overestimations of Teff. Using empirically determined fixed disease specific Teff values resulted in a better congruence between the pre- and posttherapeutic dosimetry results. 24 h measurements were marginally more accurate than 48 h ones in AMG and GD whereas 48 h measurements were marginally more accurate in ATN; these differences are however not clinically relevant. 6 d measurements are clearly less accurate than those after 24 h or 48 h. Conclusion: In ATN, AMG and GD, pretherapeutic dosimetry can be performed by a single uptake measurement at 24 h or 48 h using a fixed, disease specific value for Teff. Additional later measurements do not yield a further clinically relevant contribution to accuracy of pretherapeutic dosimetry.

Quantification of fluorescent dyes in organ tissue samples via HPLC analysis

The determination of regional blood flow via the accumulation of fluorescent microspheres is a concept regularly used in medical research. Typically, the microbeads get extracted from the tissue of interest and are then quantified by measuring the absorption or fluorescence of the incorporated dyes without further separation from the medium. However, in that case the absorption spectra of different dyes can overlap when used simultaneously, leading to an overestimation of the concentration. Additionally, background absorption from the medium can be problematic. Therefore, a high performance liquid chromatography method for the simultaneous detection of four dyes (orange, crimson, yellow-green and red) incorporated in different microbeads in samples from biological media such as organ tissue (brain, heart and kidneys) was developed. Since for biological samples often a large sample size is required for sufficient statistics, the method was optimized to yield very short run times. With this method it was possible to detect very low concentrations of only one microsphere per gram of organ tissue. By applying this sensitive quantification technique, it was demonstrated that the application of microbeads for perfusion measurements might not be reliable due to different organ distributions in each animal.

Biomimetic Remineralization of Carious Lesions by Self-Assembling Peptide

Caries is the most common disease in the world. Great efforts have been undertaken for prevention and to identify a regenerative treatment solution for dental caries. Self-assembling β-sheet forming peptides have previously shown to form 3-dimensional fiber networks supporting tissue regeneration. In particular, the self-assembling peptide P₁₁-4 has shown potential in the treatment and prevention of dental caries. It has previously been shown that application of monomeric P₁₁-4 solution to early carious lesions can increase net mineral gain by forming de novo hydroxyapatite crystals. The hypothesis for the mode of action was that monomeric self-assembling peptide P₁₁-4 diffuses into the subsurface lesion body and assembles therein into higher order fibrils, facilitating mineralization of the subsurface volume by mimicking the natural biomineralization of the tooth enamel, and it remains within the lesion body as a scaffold built-in by the newly formed hydroxyapatite. The aim of the present study was to investigate the mechanism of action of the self-assembling peptide P₁₁-4 supporting mineralization of carious enamel. By various analytical methods, it could be shown that the self-assembling peptide P₁₁-4 diffuses into the subsurface lesion, assembles into higher formed aggregates throughout the whole volume of the lesion, and supports nucleation of de novo hydroxyapatite nanocrystals and consequently results in increased mineral density within the subsurface carious lesion. The results showed that the application of self-assembling peptide P₁₁-4 can facilitate the subsurface regeneration of the enamel lesion by supporting de novo mineralization in a similar mode of action as has been shown for the natural formation of dental enamel.

Predictors of nonresponse to fluid restriction in hyponatraemia due to the syndrome of inappropriate antidiuresis

BACKGROUND

Fluid restriction (FR), the first-line treatment for hyponatraemia due to the syndrome of inappropriate antidiuresis (SIAD), often does not lead to successful correction of hyponatraemia. Therefore, predictive markers of treatment response are desirable. We evaluated routinely measured serum (s) and urine (u) parameters, s-copeptin and s-mid-regional pro-atrial natriuretic peptide (s-MR-proANP), as possible predictors of FR response.

METHODS

In this prospective observational study, we included patients with profound hyponatraemia (s-sodium <125 mmol L^-1 ) due to SIAD. Patients were classified as FR responders (increase in s-sodium concentration of >3 mmol L^-1 within 24 h) or nonresponders (increase of ≤3 mmol L^-1 within 24 h). Initial laboratory parameters were compared between groups with logistic regression analysis.

RESULTS

Of 106 SIAD patients analysed, 82 underwent treatment with FR; 48 (59%) patients showed a successful response to FR and 34 (41%) were considered nonresponders. High levels of u-sodium and u-osmolality were significantly associated with nonresponse to FR [odds ratio (OR) 15.0, 95% confidence interval (CI) 2.4-95.8, P = 0.004 and OR 34.8, 95% CI 1.2-1038.8, P = 0.041, respectively). The association of u-sodium and nonresponse remained significant also after adjustment for diuretic use. Lower levels of s-MR-proANP were associated with nonresponse (OR 0.03, 95% CI 0.003-0.3, P = 0.004), whereas s-copeptin was not significantly associated with response to FR.

CONCLUSION

Easily measured laboratory parameters, especially u-sodium, correlate with therapeutic response and identify patients most likely to fail to respond to FR. Measurement of these parameters may facilitate early treatment choice in patients with SIAD.

[Ocular Hypotension: How the Retina Surgeon Sees the Causes and Therapeutic Options]

Ocular hypotension is a result of a lack of production or a loss of intraocular fluid. Intraocular inflammation, drugs, or proliferative vitreoretinopathy (PVR) with overgrowth of the ciliary body can result in reduced secretion of intraocular fluid. Loss of intraocular fluid can result from external loss, such as in fistulating surgery or trauma, or internally, e.g. from cyclodialysis clefts or retinal detachment. In this review, we discuss the causal therapy of ocular hypotension: fixation of the ciliary body, removal of ciliary body membranes, surgery for PVR, choice of tamponade, possibilities and limitations of an iris diaphragm, and pharmacological options.

Immunoneutralization of procalcitonin as therapy of sepsis

Prior studies have demonstrated that the prohormone, procalcitonin (ProCT), and its component calcitonin precursors (CTpr) are increased in the serum of septic patients, correlate with the severity of the illness, and persist for relatively long periods of time. Animal studies in septic hamsters have revealed that the administration of ProCT is toxic and that immunoneutralization with IgG that is reactive to this molecule significantly improves survival. A large animal model of a very rapidly lethal polymicrobial sepsis has been developed in the pig in order to measure continuous physiological and metabolic parameters and also to compare the effects in this animal of an immunoneutralization, which is performed late in the course of the disease, to an identical, but early, therapy. Based upon the physiological and metabolic parameters, the late therapy, which was initiated during the fourth hour at a time when pigs were nearly moribund, was found to be as beneficial as early therapy. In both late and early therapy, the only animals to survive at the predetermined time of euthanasia were those which had received immunoneutralization therapy.

Quantitative nanoscale vortex imaging using a cryogenic quantum magnetometer

Microscopic studies of superconductors and their vortices play a pivotal role in understanding the mechanisms underlying superconductivity. Local measurements of penetration depths or magnetic stray fields enable access to fundamental aspects such as nanoscale variations in superfluid densities or the order parameter symmetry of superconductors. However, experimental tools that offer quantitative, nanoscale magnetometry and operate over large ranges of temperature and magnetic fields are still lacking. Here, we demonstrate the first operation of a cryogenic scanning quantum sensor in the form of a single nitrogen-vacancy electronic spin in diamond, which is capable of overcoming these existing limitations. To demonstrate the power of our approach, we perform quantitative, nanoscale magnetic imaging of Pearl vortices in the cuprate superconductor YBa2Cu3O7-δ. With a sensor-to-sample distance of ∼10 nm, we observe striking deviations from the prevalent monopole approximation in our vortex stray-field images, and find excellent quantitative agreement with Pearl's analytic model. Our experiments provide a non-invasive and unambiguous determination of the system's local penetration depth and are readily extended to higher temperatures and magnetic fields. These results demonstrate the potential of quantitative quantum sensors in benchmarking microscopic models of complex electronic systems and open the door for further exploration of strongly correlated electron physics using scanning nitrogen-vacancy magnetometry.

[Rehabilitation of facial palsy and vertigo in patients with vestibular schwannoma]

BACKGROUND

Facial palsy and vertigo, as symptoms of vestibular schwannoma (VS) or consequences of its therapy, have a significant impact on patients' quality of life.

OBJECTIVE

This review analyzed current literature on the topic and deduced recommendations for rehabilitation of facial palsy and vertigo.

METHODS

The present review describes a PubMed-based search of the literature of the past 10 years.

RESULTS

There is no evidence-based drug therapy for the treatment of acute facial palsy after VS surgery. Several surgical procedures for facial nerve reconstruction, muscle transfer, and static techniques have been established. Physiotherapeutic movement therapy, optimally with biofeedback, seems to improve facial function in patients with post-paralytic syndrome. Botulinum toxin injections are the method of choice for synkinesis treatment. For treatment of acute and chronic vertigo in patients with VS, the same antivertiginous drugs as for other vertigo patients are used. If the patient shows retained vestibular stimulation function, preoperative intratympanic gentamycin therapy followed by compensation training is a promising approach to decreasing postoperative vertigo. Good vestibular rehabilitation comprises intensive and regular movement training, preferably with real-time feedback and therapy control.

CONCLUSION

There are several conservative, surgical, or combined conservative-surgical treatment options for individualized facial nerve rehabilitation of VS patients, as confirmed by clinical studies. In cases of acute vertigo, standard antivertiginous pharmacotherapy is indicated. In cases of acute and also of chronic vertigo, intensive balance and movement training relieves complaints.

Cytokinin Synthesis, Signaling, and Function--Advances and New Insights

The plant hormones referred to as cytokinins are chemical signals that control numerous developmental processes throughout the plant life cycle, including gametogenesis, root meristem specification, vascular development, shoot and root growth, meristem homeostasis, senescence, and more. In addition, they mediate responses to environmental cues such as light, stress, and nutrient conditions. The core mechanistics of cytokinin metabolism and signaling have been elucidated, but more layers of regulation, additional functions, and interactions with other signals are continuously discovered and described. In this chapter, we recapitulate the highlights of over 100 years of cytokinin research covering its isolation, the elucidation of phosphorelay signaling, and how cytokinin functions in various developmental contexts including its interaction with other pathways. Additionally, given cytokinin's paracrine signaling mechanism, we postulate that cellular exporters for cytokinins exist.

[Social Security Needs Social Medicine: Self-image of Physicians Practicing Social Medicine in Statutory Health Insurances and Social Security Systems]

OBJECTIVE

In January, 2014, the division "Social Medicine in Practice and Rehabilitation" of the German Society for Social Medicine and Prevention established a working group on the self-image of the physicians active in the field of social medicine (medical expertise and counseling).

METHODS

The result of this work is the contribution presented here after consensus was achieved by specialists of social medicine from different fields and institutions (social security etc.) and in good cooperation with Prof. Dr. Gostomzyk and Prof. Dr. Robra.

RESULTS

Based on the importance of an up to date social medicine for claimants and recipients of benefits on the one hand and the social security system on the other, and also on a description of the subjects, objectives and methods the following aspects are presented: · The perspective of social medicine. · Qualification in social medicine, concerning specialist training and continuing medical education. · The fields of duty of experts in social medicine. · The proceedings in social medicine. The working group identified challenges for the specialists in social medicine by a narrowed perception of social medicine by physicians in hospitals and practice, accompanied by an enlarged importance of expertise in social medicine, by the demand for more "patient orientation" and gain of transparency, and concerning the scientific foundation of social medicine.

CONCLUSIONS

The working group postulates: · The perspective of social medicine should be spread more widely.. · Confidence in experts of social medicine and their independency should be strengthened.. · The not case-related consulting of the staff and executives should be expanded.. · Social medicine in practice needs support by politics and society, and especially by research and teaching.. · Good cooperation and transfer of experiences of the different branches of social security are essential for the impact of social medicine..

Blood flow assessed by color Doppler imaging in retinopathy of prematurity

OBJECTIVE

To quantify central retinal arterial and venous blood flow using ultrasound color Doppler imaging.

STUDY DESIGN

In this prospective observational study, eyes of eight preterm infants with retinopathy of prematurity stage 2 and of eight preterm infants without retinopathy (gestational age <30 weeks, birth weight <1500 g) were evaluated by color Doppler imaging.

RESULT

Ocular blood flow velocities measured at 28±1 days of life did not differ significantly in the eyes of preterm infants who subsequently did and did not develop retinopathy. Development of retinopathy was associated with highly significant (P<0.0001 each) increases in central retinal vein maximum velocities (from 1.99±0.36 to 3.72±0.61 cm s(-1)), central retinal artery systolic flow velocities (from 6.44±1.52 to 9.87±1.99 cm s(-1)) and flow velocity integrals (from 1.27±0.30 to 2.17±0.50 cm) at 64±13 days of life. In infants without retinopathy, no significant changes were observed except for an increase in central retinal vein maximum velocities (from 1.96±0.22 to 2.62±0.44 cm s(-1), P=0.003).

CONCLUSION

Retinopathy of prematurity appears to be accompanied by increased retinal blood flow.

What is healthy food? Objective nutrient profile scores and subjective lay evaluations in comparison

To date, it is unclear how consumers evaluate the healthiness of individual foods and meals and how consumers' perceptions are related to expert opinions. This knowledge is essential for efficient communication of nutrition information with the goal of promoting healthy eating. This study used the fake food buffet method to investigate health perceptions of selected meals and of 54 individual foods and beverages. Lay consumers' subjective healthiness evaluations of meals and foods were compared to objective nutrient profile scores, which were previously shown to correlate highly with expert opinions. The results show that nutrition profile scores and lay evaluations were highly correlated, which indicates that lay people used similar criteria as experts to evaluate the healthiness of foods. However, lay consumers tended to neglect the amount of saturated fat, protein and sodium for their judgments. Also, it was found that while lay consumers were quite able to evaluate single food products, they had difficulties in evaluating entire meals. Future interventions should focus particularly on educating the consumer about the negative effects of diets high in salt and saturated fat and they should improve the consumer's abilities to evaluate entire meals.

Mid-regional pro-atrial natriuretic peptide and the assessment of volaemic status and differential diagnosis of profound hyponatraemia

BACKGROUND

Hyponatraemia is common and its differential diagnosis and consequent therapy management is challenging. The differential diagnosis is mainly based on the routine clinical assessment of volume status, which is often misleading. Mid-regional pro-atrial natriuretic peptide (MR-proANP) is associated with extracellular and cardiac fluid volume.

METHODS

A total of 227 consecutive patients admitted to the emergency department with profound hypo-osmolar hyponatraemia (Na < 125 mmol L(-1) ) were included in this prospective multicentre observational study conducted in two tertiary centres in Switzerland. A standardized diagnostic evaluation of the underlying cause of hyponatraemia was performed, and an expert panel carefully evaluated volaemic status using clinical criteria. MR-proANP levels were compared between patients with hyponatraemia of different aetiologies and for assessment of volume status.

RESULTS

MR-proANP levels were higher in patients with hypervolaemic hyponatraemia compared to patients with hypovolaemic or euvolaemic hyponatraemia (P = 0.0002). The area under the curve (AUC) to predict an excess of extracellular fluid volume, compared to euvolaemia, was 0.73 [95% confidence interval (CI) 0.62-0.84]. Additionally, in multivariate analysis, MR-proANP remained an independent predictor of excess extracellular fluid volume after adjustment for congestive heart failure (P = 0.012). MR-proANP predicted the syndrome of inappropriate antidiuresis (SIAD) versus hypovolaemic and hypervolaemic hyponatraemia with an AUC of 0.77 (95% CI 0.69-0.84).

CONCLUSION

MR-proANP is associated with extracellular fluid volume in patients with hyponatraemia and remains an independent predictor of hypervolaemia after adjustment for congestive heart failure. MR-proANP may be a marker for discrimination between the SIAD and hypovolaemic or hypervolaemic hyponatraemia.