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The branchiomeric skeletal muscles co-evolved with new chambers of the heart to enable predatory feeding in chordates. These co-evolved tissues develop from a common population in anterior splanchnic mesoderm, referred to as cardiopharyngeal mesoderm (CPM). The regulation and development of CPM are poorly understood. We describe an embryonic stem cell-based system in which MESP1 drives a PDGFRA+ population with dual cardiac and skeletal muscle differentiation potential, and gene expression resembling CPM. Using this system, we investigate the regulation of these bipotent progenitors, and find that cardiac specification is governed by an antagonistic TGFβ-BMP axis, while skeletal muscle specification is enhanced by Rho kinase inhibition. We define transcriptional signatures of the first committed CPM-derived cardiac and skeletal myogenic progenitors, and discover surface markers to distinguish cardiac (PODXL+) from the skeletal muscle (CDH4+) CPM derivatives. These tools open an accessible window on this developmentally and evolutionarily important population.

Objective: In auditory brainstem implant (ABI) surgery, array placement may be optimized by electrophysiological information of adequate brainstem activation gained from electrically evoked auditory brainstem responses (EABR). This study aims 1) to characterize in detail the EABR from ABI implantation, 2) to introduce an EABR Classification Scheme, and 3) to analyze data for their correlation with individual patients' findings., Methods: Out of a continuous series of 54 patients who received an ABI between 2005 and 2019, 23 Neurofibromatosis Type 2 patients with complete documentation of 154 recordings were selected for offline analysis and for development and evaluation of a new EABR Classification Scheme comprising Class A: three vertex positive peaks, Class B:two peaks, Class C: a combination of one peak and a second melted double peak, Class D: one sole vertex positive peak and Class E: no peaks., Results: All 23 subjects showed EABR at final ABI position and experienced auditory sensations at first activation. The most frequent morphology consisted of two peaks, Classes B and C. Identified mean latencies were for P1 0.42 ms (±0.095), P2 1.42 ms (±0.244) and P3 2.41 ms (±0.329). Peak latencies correlated positively with tumor extensions (p < 0.005)., Conclusions: This study provides clear instructions on optimal EABR performance and evaluation., Significance: The new EABR Classification Scheme relies on a fast "online" identification of vertex positive peaks at the estimated post-artifact phase. The variability in EABR morphology provides an individual snapshot of the actual structural and functional status of the brainstem., (Copyright © 2023 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Printer toner particles (TPs) are a common, potentially hazardous substance, with an unclear toxicological impact on the respiratory mucosa. Most of the airways surface is covered by a ciliated respiratory mucosa, therefore appropriate tissue models of the respiratory epithelium with a high in vivo correlation are necessary for in vitro evaluation of airborne pollutants toxicology and the impact on the functional integrity. The aim of this study is the evaluation of TPs toxicology in a human primary cell-based air-liquid-interface (ALI) model of respiratory mucosa. The TPs were analyzed and characterized by scanning electron microscopy, pyrolysis and X-ray fluorescence spectrometry. ALI models of 10 patients were created using the epithelial cells and fibroblasts derived from nasal mucosa samples. TPs were applied to the ALI models via a modified Vitrocell® cloud and submerged in the dosing 0.89 - 892.96 µg/ cm 2 . Particle exposure and intracellular distribution were evaluated by electron microscopy. The MTT assay and the comet assay were used to investigate cytotoxicity and genotoxicity, respectively. The used TPs showed an average particle size of 3 - 8 µm. Mainly carbon, hydrogen, silicon, nitrogen, tin, benzene and benzene derivates were detected as chemical ingredients. By histomorphology and electron microscopy we observed the development of a highly functional, pseudostratified epithelium with a continuous layer of cilia. Using electron microscopy, TPs could be detected on the cilia surface and also intracellularly. Cytotoxicity was detected from 9 µg/ cm 2 and higher, but no genotoxicity after ALI and submerged exposure. The ALI with primary nasal cells represents a highly functional model of the respiratory epithelium in terms of histomorphology and mucociliary differentiation. The toxicological results indicate a weak TP-concentration-dependent cytotoxicity. AVAILABILITY OF DATA AND MATERIALS: The datasets used and analysed during the current study are available from the corresponding author on reasonable request., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Till Jasper Meyer reports financial support was provided by Interdisciplinary Centre for Clinical Science (IZKF) at the University of Würzburg. Maria R. Steinke reports financial support was provided by Deutsche Forschungsgemeinschaft. Stephan Hackenberg reports financial support was provided by Deutsche Forschungsgemeinschaft., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Canine heartworm disease (CHD) results from infection with Dirofilaria immitis and while it is of global concern, it is most prevalent in tropical climates where conditions support the parasite and vector life cycles. Melarsomine dihydrochloride is the sole treatment for CHD recommended by the American Heartworm Society. However, in cases where cost or access to melarsomine precludes treatment of an infected dog, therapeutic alternatives are warranted. This randomized, controlled field study evaluated the adulticidal efficacy of a combination therapeutic protocol using 10 % imidacloprid + 2.5 % moxidectin spot-on and a single 28-day course of doxycycline and compared with that of a 2-dose melarsomine dihydrochloride protocol. Of 37 naturally-infected domestic dogs with class 1, 2 or early class 3 CHD enrolled in the study, 30 were evaluated for a minimum of 12 months. Seven dogs were withdrawn due to canine ehrlichiosis, non-compliance, or wrongful inclusion. Dogs were randomly assigned to a control (CP, n = 15) or investigational (IVP, n = 15) treatment group. CP dogs received two injections of melarsomine dihydrochloride (2.5 mg/kg) 24 -hs apart and maintained on monthly ivermectin/pyrantel. IVP dogs were treated with oral doxycycline (10 mg/kg twice daily for 28 days) and topical 10 % imidacloprid + 2.5 % moxidectin once monthly for 9 months. Dogs were evaluated up to 18 months - monthly for the first 9 months, then every 3 months. Parasiticidal efficacy was based on antigen status using the IDEXX PetChek® 34 Heartworm-PF Antigen test. By month 18, antigen was not detected in any study dog except one from the IVP group. One other IVP dog was persistently antigenemic and treated with melarsomine at month 12 according to the initial study protocol. Mean antigen concentration (based on optical density) decreased more rapidly in the CP group and by month 15 was 0.11 for the IVP and 0.07 for CP groups, with equivalent median concentrations (0.04) in both groups. Conversion following heat-treatment of antigen-negative samples occurred frequently and at similar rates in both treatment groups. Based on the bias of diagnostic tests towards detection of female worms, we conclude that monthly application of 10 % imidacloprid + 2.5 % moxidectin for 9 months combined with a course of doxycycline twice daily for 28 days resulted in effective therapy against female adults in CHD. This therapeutic option may be particularly useful in cases where financial constraint or access to melarsomine precludes treatment of an infected individual. This study was supported by Bayer Animal Health., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: Outcome in vestibular schwannoma (VS) surgery has improved enormously over the last decades. Surgical positioning remains a matter of discussion. A standardized protocol for diagnostics and management has been applied and evaluated for complications and functional outcome., Methods: We examined 502 VS tumors in 483 patients (227 men and 256 women) between 2005 and 2016. According to our patient selection and treatment algorithm, 488 operations (97%) were performed in the semi-sitting position, and 14 (3%) were in the supine position. Auditory and facial functions were analyzed before and after surgery as were perioperative complications., Results: There were 182 patients (36%) with small tumors (Hannover classification T1-T3A) and 320 (64%) large tumors (T3B or T4). Of the patients, 14% were neurofibromatosis type 2 cases. Complete tumor resection was achieved in 96.4%. Hearing preservation occurred in 44% of patients with small tumors and 23% of those with large tumors (Hannover classification), and correlated significantly with tumor size (P < 0.001). Facial palsy (House Brackmann grades II-VI) was present in 63 patients before and in 185 patients after surgery. Useful facial function (House Brackmann grades I-III) early after surgery was maintained in 86% of patients with small tumors and in 77% of patients with large tumors. Intraoperative complications included air embolism in 45 cases (9%), sinus injury in 3 cases, cerebrospinal fluid leakage in 46 cases (9%), and local hemorrhage in 19 cases (4%). Surgical revision was indicated in 31 cases (6%)., Conclusions: In a standardized setting, the semi-sitting position allowed a safe approach. This setting offers the advantage of bimanual tumor nerve handling by the surgeon and an optimal visualization of important functional structures., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: A cochlear implant (CI) is an electronic prosthesis that can partially restore speech perception capabilities. Optimum information transfer from the cochlea to the central auditory system requires a proper functioning auditory nerve (AN) that is electrically stimulated by the device. In deafness, the lack of neurotrophic support, normally provided by the sensory cells of the inner ear, however, leads to gradual degeneration of auditory neurons with undesirable consequences for CI performance., Methods: We evaluated the potential of adipose-derived stromal cells (ASCs) that are known to produce neurotrophic factors to prevent neural degeneration in sensory hearing loss. For this, co-cultures of ASCs with auditory neurons have been studied, and autologous ASC transplantation has been performed in a guinea pig model of gentamicin-induced sensory hearing loss., Results: In vitro ASCs were neuroprotective and considerably increased the neuritogenesis of auditory neurons. In vivo transplantation of ASCs into the scala tympani resulted in an enhanced survival of auditory neurons. Specifically, peripheral AN processes that are assumed to be the optimal activation site for CI stimulation and that are particularly vulnerable to hair cell loss showed a significantly higher survival rate in ASC-treated ears., Discussion/conclusion: ASC transplantation into the inner ear may restore neurotrophic support in sensory hearing loss and may help to improve CI performance by enhanced AN survival., (Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Objective: The auditory brainstem response (ABR) may be a predictor of postoperative cochlear nerve function. In this study, the course of intraoperative ABR monitoring was analyzed to find predictive markers for postoperative hearing function., Patients and Methods: From 2010 to 2012, 46 patients who had had vestibular schwannoma surgery were investigated by intraoperative ABR monitoring. The type of ABR development was identified: type A, improved or stable ABR; type B, fluctuating or deteriorated ABR; and type C, slow or sudden ABR loss. Hearing function was correlated with ABR monitoring., Results: The different types of ABR development showed a strong correlation with postoperative hearing (P < 0.001). ABR quality after 60% tumor removal was independently significant for hearing outcome. Possible interpretations are: 1) Independent of positive factors at the start of surgery at the final phase of tumor resection, what mattered for hearing outcome was the ABR quality (P < 0.001). 2) Dependence on ABR quality in the last phase might be a result of what the cochlear nerve has endured during resection. 3) The importance of ABR quality in the last phase might be because the tumor capsule is dissected from the nerves in that final phase., Analysis: of critical actions with incidence of ABR impairment showed that dissection in the internal auditory canal and drilling were most critical., Conclusions: Intraoperative ABR development is a predictive factor for postoperative hearing outcome. Deterioration should be avoided, because ABR improvement as a result of good status at the beginning of surgery could not be assumed., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: Some patients suffer postoperative hearing loss even when the intraoperative auditory brainstem response (ABR) is preserved during vestibular schwannomas surgery. This study was conducted to evaluate whether there are dynamic changes of the ABR after surgery., Patients and Methods: In a prospective study from 2010-2012, 46 patients (24 female and 22 male) with vestibular schwannomas were investigated by intraoperative and postoperative ABR monitoring. Development of ABR quality during and after surgery (Class 1 normal, Class 5 complete loss) was correlated to auditory outcome., Results: At the end of surgery, 17 patients had an ABR Class 1-4 and 29 had Class 5. Four hours after surgery, 9 of 23 (39%) patients showed an ABR quality change, and 24 hours after surgery, 15 of 30 (50%) had undergone ABR quality changes. Four different types of postoperative ABR courses could be distinguished-Course 1: stable with reproducible ABR, Course 2: unstable with reproducible ABR, Course 3: unstable with ABR loss, and Course 4: stable with ABR loss. These courses correlated highly significantly with the intraoperative development (P < 0.001) and with hearing outcome (P = 0.003)., Conclusion: The study identifies ongoing changes of ABR quality and hearing function after the end of vestibular schwannoma surgery. Therefore it seems worthwhile to continue ABR monitoring in the postoperative phase in order to identify patients who are at risk of a secondary hearing deterioration and start therapeutic interventions in a timely manner., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: Auditory brainstem response (ABR) monitoring is regularly used in surgery of vestibular schwannoma to achieve hearing preservation. Despite ABR preservation at the end of surgery, there are cases with postoperative deafness. To date it is unclear whether these are false positive ABR data or cases of secondary hearing loss. In this pilot study, we focused on the early postoperative phase and possible ABR changes in this period., Patient and Method: In a prospective study from March 2008 to April 2009, eleven patients (5 female and 6 male) with vestibular schwannoma and preoperative residual hearing were investigated by repeated postoperative ABR investigation at seven dates during the first week. ABR results, hearing function and tumor extension were categorized according to Hannover classification system. The postoperative developments of the first week after surgery are described., Results: Hearing preservation was achieved in 55% (6 of 11) of the patients. In the early postoperative phase, three patients with an ABR loss at the end of surgery showed some kind of recovery. In one case, a permanent recovery could be reproduced and developed step by step during the early postoperative phase. Three patients showed a postoperative deterioration resulting in a complete ABR loss. In one of these cases, it was probably a technical problem, but in the two other cases it was a real impairment. In 8 of 11 ABR, quality changed considerably during the early postoperative phase., Conclusion: This pilot study identifies considerable change of ABR formation occurring in a considerable proportion of patients early after vestibular schwannoma resection. Obviously, in some patients, the endoperative state of the ABR is not the final state. Some patients show a postoperative improvement and some a deterioration towards a complete loss of all ABR components. Whether secondary hearing loss could be presented by early detection, will be a matter of further studies., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Human nasal miniorgan cultures (MOC) are a useful tool in ecogenotoxicology. Repetitive exposure to nicotine showed reversible DNA damage, and stable CYP2A6 expression was demonstrated in nasal MOC in previous investigations. The aim of the present study was to evaluate the genotoxic effect of nicotine in nasal MOC after chronic nicotine exposure, and to monitor possible metabolism capacities. MOC were dissected from human nasal mucosa and cultured under standard cell culture conditions. MOC were exposed to nicotine for 3 weeks at concentrations of 1 μM and 1 mM. The concentrations were chosen based on nicotine plasma levels in heavy smokers, and possible concentrations used in topical application of nicotine nasal spray. DNA damage was assessed by the comet assay at days 7, 14 and 21. Concentrations of nicotine and cotinine were analyzed in cell culture medium by gas chromatography/mass spectrometry to determine a possible metabolism of nicotine by MOC. Distinct DNA damage in MOC could be demonstrated after 1 week of exposure to 1 μM and 1 mM nicotine. This effect decreased after 2 and 3 weeks with no statistically relevant DNA migration. No nicotine metabolism could be detected by changes in nicotine and cotinine concentrations in the supernatants. This is the first time genotoxic effects have been evaluated in nasal MOC after chronic nicotine exposure for up to 3 weeks. Genotoxic effects were present after 1 week of culture with a decrease over time. Down-regulation of nicotinic acetylcholine receptors, which are expressed in nasal mucosa, may be a possible explanation. The lack of nicotine metabolism in this model could be explained by the functional loss of CYP2A6 during chronic nicotine exposure. Further investigations are necessary to provide a more detailed description of the underlying mechanisms involved in DNA damage by nicotine., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Human induced land use changes negatively impact the viability of many wildlife species through habitat modifications and mortality, while some species seem to benefit from it. Roe deer (Capreolus capreolus), a wide spread ungulate increased both its abundance and range throughout Europe. This pattern is also reflected in the increasing hunting bags over the last 40 years. Such a development raises questions about the relationship between human hunting and population dynamics and, in particular, about the potential of human hunting to control related populations. We analysed and reconstructed annual hunting bags of roe deer for three federal states of northern Germany, Brandenburg, Lower Saxony and Mecklenburg West Pomerania for the years 1972 to 2011. Since 1992 the hunting bags from these three states are significantly higher than those reported for the years 1972-1991. Our reconstruction takes into consideration effects of climate variability, expressed by inter-annual changes in the North Atlantic Oscillation and impacts from rapeseed and wheat cultivation. We found that severe winters, which are indicated by negative values of the North Atlantic Oscillation during the months December-March, directly, or with a time lag of two years affect the number of deer shot. In contrast, an increase in the area used for rapeseed cultivation coincides with higher numbers of roe deer shot, with respect to the overall mean value. Consequently, we recommend that wildlife management addresses changes in large scale processes including land use pattern and climate variability., (© 2013.)

Background Aims: Adipose-derived stem cells (ASCs) are a promising mesenchymal cell source for tissue engineering approaches. To obtain an adequate cell amount, in vitro expansion of the cells may be required in some cases. To monitor potential contraindications for therapeutic applications in humans, DNA strand breaks and chromosomal aberrations in ASCs during in vitro expansion were examined., Methods: After isolation of ASC from human lipoaspirates of seven patients, in vitro expansion over 10 passages was performed. Cells from passages 1, 2, 3, 5 and 10 were used for the alkaline single-cell microgel electrophoresis (comet) assay to detect DNA single-strand breaks and alkali labile as well as incomplete excision repair sites. Chromosomal changes were examined by means of the chromosomal aberration test., Results: During in vitro expansion, ASC showed no DNA single-strand breaks in the comet assay. With the chromosomal aberration test, however, a significant increase in chromosomal aberrations were detected., Conclusions: The study showed that although no DNA fragmentation could be determined, the safety of ASC cannot be ensured with respect to chromosome stability during in vitro expansion. Thus, reliable analyses for detecting ASC populations, which accumulate chromosomal aberrations or even undergo malignant transformation during extensive in vitro expansion, must be implemented as part of the safety evaluation of these cells for stem cell-based therapy., (Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Various hypotheses on the origin of cancer stem cells (CSCs) exist, including that CSCs develop from transformed human bone marrow mesenchymal stem cells (hBMSC). Since the polyether antibiotic salinomycin selectively kills CSCs, the present study aims to elucidate the effects of salinomycin on normal hBMSC. The immunophenotype of hBMSC after salinomycin exposure was observed by flow cytometry. The multi-differentiation capacity of hBMSC was evaluated by Oil Red O and van Kossa staining. Cytotoxic effects of salinomycin were monitored by the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay. Furthermore, spheroid formation and migration capacity were assessed. There were no differences in the immunophenotype and multi-differentiation capacity of hBMSC induced by salinomycin treatment. Cytotoxic effects were observed at concentrations of 30 μM and above. Neither the migration capability nor the ability to form spheroids was affected. Essential functional properties of hBMSC were unaffected by salinomycin. However, dose-dependent cytotoxicity effects could be observed. Overall, low dose salinomycin showed no negative effects on hBMSC. Since mesenchymal stem cells from various sources respond differently, further in vitro studies are needed to clarify the effect of salinomycin on tissue-specific stem cells., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

The role of the tobacco-alkaloid nicotine in tumour biology is widely discussed in the literature. Due to a strong capacity to induce angiogenesis, a pro-mutagenic potential in non-tumour and cancer cells, and a pro- and anti-apoptotic influence, nicotine seems to promote the growth of established tumours. However, results indicating DNA damage and genetic instability associated with nicotine have been contradictory thus far. A variety of markers and endpoints of genotoxicity are required to characterize the genotoxic potential of nicotine. Induction of DNA single- and double-strand breaks, the formation of micronuclei, and the induction of sister chromatid exchange and chromosome aberrations represent possible genotoxicological endpoints at different cellular levels. Human lymphocytes were exposed to nicotine concentrations between 1μM and 1mM for 24h in vitro. The comet assay, the cytokinesis-block micronucleus test, the chromosome aberration (CA) test, and the sister chromatid exchange (SCE) test were then applied. Viability and apoptosis were measured by flow cytometry in combination with the annexin V-propidium iodide staining test. In this test setting, no enhanced DNA migration was measured by the comet assay. An increase in the micronucleus frequency was detected at a concentration of 100μM nicotine without affecting the frequency of apoptotic cells. A distinct genotoxic effect was determined by the CA test and the SCE test, with a significant increase in CA and SCE at a concentration of 1μM. In the annexin V test, nicotine did not influence the proportion of apoptotic or necrotic cells. The current data indicating the induction of CA by nicotine underscore the necessity of ongoing investigations on the potential of nicotine to initiate mutagenesis and tumour promotion. Taking into account the physiological nicotine plasma levels in smokers or in nicotine-replacement therapy, particularly the long-term use of nicotine should be critically discussed., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Epithelium of the upper and lower airways is a common origin of tobacco-related cancer. The main tobacco alkaloid nicotine may be associated with tumor progression. The potential of nicotine in inducing DNA mutations as a step towards cancer initiation is still controversially discussed. Different subtypes of nicotinic acetylcholine receptors (nAChR) are expressed in human nasal mucosa and a human bronchial cell line representing respiratory mucosa as a possible target for receptor-mediated pathways. In the present study, both cell systems were investigated with respect to DNA damage induced by nicotine and its mechanisms. Specimens of human nasal mucosa were harvested during surgery of the nasal air passage. After enzymatic digestion over night, single cells were exposed to an increasing nicotine concentration between 0.001 mM and 4.0mM. In a second step co-incubation was performed using the antioxidant N-acetylcysteine (NAC) and the nAChR antagonist mecamylamine. DNA damage was assessed using the alkali version of the comet assay. Dose finding experiments for mecamylamine to evaluate the maximal inhibitory effect were performed in the human bronchial cell line BEAS-2B with an increasing mecamylamine concentration and a constant nicotine concentration. The influence of nicotine in the apoptotic pathway was evaluated in BEAS-2B cells with the TUNEL assay combined with flow cytometry. After 1h of nicotine exposure with 0.001, 0.01, 0.1, 1.0 and 4.0mM, significant DNA damage was determined at 1.0mM. Further co-incubation experiments with mecamylamine and NAC were performed using 1.0mM of nicotine. The strongest inhibitory effect was measured at 1.0mM mecamylamine and this concentration was used for co-incubation. Both, the antioxidant NAC at a concentration of 1.0mM, based on the literature, as well as the receptor antagonist were capable of complete inhibition of the nicotine-induced DNA migration in the comet assay. A nicotine-induced increase or decrease in apoptosis as assessed by the TUNEL assay in BEAS-2B could not be detected. These results support the hypothesis that oxidative stress is responsible for nicotine-induced DNA damage. Similar results exist for other antioxidants in different cell systems. The decrease in DNA damage after co-incubation with a nAChR antagonist indicates a receptor-dependent pathway of induction for oxidative stress. Further investigations concerning pathways of receptor-mediated DNA damage via nAChR, the role of reactive oxygen species and apoptosis in this cell system will elucidate underlying mechanisms., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Objective: To obtain information on functional integrity of the facial nerve by transcranial electrical motor evoked potentials independent of nerve visualization and to improve prediction of postoperative function., Patients and Methods: In a prospective clinical study, 68 patients with cerebello-pontine angle tumors and 5 patients with trigeminal neuralgia were investigated by facial motor evoked potentials (FMEP) elicited by multi-pulse transcranial electrical motor cortex stimulation. For recording the same electrode set-up was used as for continuous EMG monitoring of the orbicularis oculi and oris muscles. Pre-surgical FMEP amplitudes and latencies were correlated with tumor extensions. End to start amplitude ratios were compared to early and long-term facial nerve function by House-Brackmann-Grading (HB) documented by pre- and post-operative photo and video documentation., Results: Reliable FMEP were obtained in 57 patients. FMEP responses at the start of surgery correlated with the degree of tumor extension. Largest FMEP amplitudes and shortest latencies were found in patients with trigeminal neuralgia. FMEP quality was reduced with increasing tumor extension (P<0.05). The ratio of end-operative to start-operative FMEP-amplitude showed a positive correlation with early and late facial nerve function. Correlation was especially close with early function: an amplitude preservation rate of 86% led to HB°1 or HB°2, of 67% to HB°3, at 33% to HB°4 and at 15% or lower to HB°5 or HB°6., Discussion: Initial FMEP amplitudes correlate with the presumed pre-operative nerve affection by space occupying tumors, a phenomenon reported here for the first time. Intact FMEP are highly reliable for preserved nerve continuity and hereby are of special help to the neurosurgeon for those surgical phases where the facial nerve is not visible and still covered by tumor and where conventional EMG monitoring is of very limited use. The end-to-start amplitude ratio of the FMEP is closely related to early and late clinical function. Amplitude reduction by 30% or more should result in a change of microsurgical action to enable fast recovery., Conclusion: As an adjunct to intraoperative EMG, FMEP are superior in two respects, first in identifying pre-surgical latent nerve lesions and second in monitoring nerve integrity without direct nerve visualization. FMEP are highly reliable in predicting early and late postoperative function., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background Aims: The chondrogenic differentiation potential of mesenchymal stromal cells (MSC), as well as their immunosuppressive properties, have been studied extensively. So far, only a few studies have addressed the question of whether MSC still retain their immunosuppressive qualities after transdifferentiation. In particular, the expression of immunogenic markers, such as human leukocyte antigen (HLA)-DR, after differentiation has never been investigated., Methods: Chondrogenic transdifferentiation was induced in human adipose tissue-derived stem cell (ADSC) pellet cultures derived from 10 different patients, using 10 ng/mL transforming growth factor (TGF)-β3. Samples were harvested over a time-course of 28 days and analyzed by immunohistochemistry and reverse transcription (RT)-polymerase chain reaction (PCR). The cytokine levels in the supernatants of the samples were measured semi-quantitatively by dot-blots and quantitatively by enzyme-linked immunosorbant assays (ELISA)., Results: Undifferentiated ADSC were negative for chondrogenic markers, as well as HLA-ABC and HLA-DR epitopes in immunofluorescence. In contrast, TGF-β3-induced pellet cultures showed both expression of chondrogenic differentiation markers, such as transcription factor 9 (Sox 9), collagen type IIa and aggrecan, and an up-regulation of HLA-DR, beginning at day 7 after induction. Interferon-γ (INF-γ) is known to up-regulate HLA-DR. Therefore we measured INF-γ levels in the supernatants of TGF-β3-induced pellets and, indeed, INF-γ was up-regulated during chondrogenesis in ADSC pellet cultures. However, both undifferentiated and TGF-β3-induced ADSC also showed expression of immunosuppressive HLA-G and interleukin (IL)-10 up-regulation., Conclusions: These results suggest that the immunogenicity of adult stem cell-derived tissue should be tested in animal models before clinical trials for allogeneic engineered tissue are considered.

Silver nanoparticles (Ag-NPs) are the most frequent commercialized nanomaterial currently. Due to a distinct lack of information on hazardous properties of Ag-NPs in human cells, a study was conducted to evaluate Ag-NP induced DNA damage, cell death and functional impairment in human mesenchymal stem cells (hMSCs). Initially, Ag-NPs and their cellular distribution were characterized by transmission electron microscopy (TEM). Ag-NPs were exposed to hMSCs for 1, 3 and 24h. Cytotoxicity was measured by the trypan blue exclusion test and the fluorescein-diacetate test, DNA damage was evaluated by the comet assay and chromosomal aberration test. Cytokine release of IL-6, IL-8 and VEGF was observed using the ELISA technique. Additionally, hMSC migration capability was tested in a transwell system. TEM revealed a Ag-NP distribution to cytoplasm and nucleus. Cytotoxic effects were seen at concentrations of 10 μg/ml for all test exposure periods. Both, comet assay and chromosomal aberration test showed DNA damage after 1, 3, and 24h at 0.1 μg/ml. A significant increase of IL-6, IL-8 and VEGF release indicates hMSC activation. Migration ability was not impaired at subtoxic concentrations. In conclusion, we demonstrated cyto- and genotoxic potential of Ag-NPs in hMSCs at significantly higher concentrations as compared to antimicrobial effective levels., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Background: The insulin-induced gene 1 (INSIG1) encodes a protein that blocks proteolytic activation of sterol regulatory element binding proteins, which are transcription factors that activate genes that regulate cholesterol, fatty acid, and glucose metabolism., Objective: We tested for associations between 6 INSIG1 tag single nucleotide polymorphisms (SNPs) (and captured all common variations in INSIG1) and the risk of type 2 diabetes (T2D), obesity, and related traits in 10,567 adults and 1155 adolescents from 5 population-based studies, a T2D case-control study, and a T2D case-series., Design: We genotyped tag SNPs and tested them for associations with the risk of T2D or obesity and with body mass index, waist circumference, systolic and diastolic blood pressure, and concentrations of fasting glucose, 2-h oral-glucose-tolerance test glucose, cholesterol, and triglyceride, with the assumption of an additive effect of the minor allele. Dominant effects were tested for the less-frequent SNPs (minor allele frequency <5%). Summary statistics of each study underwent meta-analysis., Results: Meta-analyses, which included 1655 T2D cases and 2911 control subjects, showed no association between any of the INSIG1 SNPs and T2D (P > 0.08). Furthermore, none of the SNPs showed an association with obesity in 1666 obese and 5737 nonobese individuals (P > 0.17). In agreement, none of the associations between the SNPs and any of the metabolic traits showed convincing associations in the 7562 adults from 4 population-based studies. Although a few nominally significant associations emerged, none of the associations survived multiple-testing correction. We observed no convincing associations with any of the studied traits in 1155 adolescents., Conclusion: Although our study was sufficiently powered to identify small effects, the results suggest that common variation in INSIG1 is unlikely to have a major effect on T2D and obesity risk and related traits in white Europeans.

Nanomaterials are defined as substances with at least one dimension smaller than 100nm in size and are used for a multitude of purposes. Titanium dioxide nanoparticles (TiO(2)-NPs) are an important material used as an additive in pharmaceutical and cosmetic products. Due to their high surface-to-mass index, TiO(2) nanoparticles show different physical and chemical characteristics compared to the bulk substance. The knowledge about geno- or cytotoxic effects of TiO(2)-NPs is incomplete since existing studies show contrary results. Human nasal mucosa cells were obtained from 10 donors and exposed to TiO(2)-NPs in increasing concentrations of 10, 25, 50 und 100mug/ml. Transmission electron microscopy (TEM) was applied to document particle morphology and size distribution, the degree of particle aggregation and the distribution of particles in inter- and intracellular spaces. Furthermore, DNA fragmentation and cytotoxicity caused by TiO(2)-NPs were evaluated. DNA strand breakage was detected by single-cell microgel electrophoresis (comet) assay. Cytotoxic effects were analyzed by trypan blue exclusion test and fluorescein diacetate (FDA) assay. TiO(2) particles used in this study were mainly nanosized but also showed a strong tendency to aggregate in spite of sonication of the suspension. Particles entered the cytoplasm in 11% and the cell nucleus in 4%. The trypan blue exclusion test and the FDA assay did not show any loss of cell viability. In the comet assay, there was no evidence of increased DNA damage for TiO(2)-NPs. In this pilot project, no cyto- or genotoxic effects could be shown for TiO(2)-NPs on human nasal epithelial cells. Further investigations will focus on a variety of metal oxide nanoparticles to describe the biocompatibility in the human organism., (Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.)

Customizing auricles with biodegradable polyurethane colonized with autologous chondrocytes as an approach for tissue engineering cartilage transplants has been suggested for the reconstruction of the external ear to repair auricular deformities. Dextrose, triethanolamine and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEG-PPG-PEG) are matrices of an open-pored polyurethane three-dimensional scaffold. After release from the polymer, these compounds can be absorbed into the human organism. Therefore, cytotoxic effects on human chondrocytes and lymphocytes and genotoxic effects on human lymphocytes were determined. Propidium iodide and fluoresceine diacetate staining as well as quantitative proliferations testing with EZ4U served to detect cytotoxic effects on chondrocytes. In lymphocytes cytotoxicity was checked by trypan blue staining and the alkaline single cell microgel electrophoresis (Comet) assay was used to study genotoxic effects. Dose-dependent cytotoxicity and genotoxicity of the matrices could be shown. Concentrations up to 4.25mg/ml for dextrose, 0.15 mg/ml for PEG-PPG-PEG and 0.9 mg/ml for triethanolamine did not show cytotoxic effects in chondrocytes or genotoxic effects in lymphocytes. These data suggest that dextrose, triethanolamine and PEG-PPG-PEG could be safely used if scaffolds made of open-pored polyurethane do not release these compounds at a rate giving higher concentrations at the site of implantation or in body fluids, respectively.

The tobacco alkaloid nicotine is responsible for addiction to tobacco and supposed to contribute to tobacco carcinogensis, too. Recently, genotoxic effects of nicotine have been reported in human cells from blood and upper aerodigestive tract. Because of nicotine accumulation in saliva, the study of possible in vitro genotoxic effects of nicotine have been extended to human salivary gland cells. Specimens of parotid glands of 10 tumor patients were obtained from tumor-free tissue. Single cells were prepared by enzymatic digestion immediately after surgery and exposed for 1h to 0.125-4.0mM of nicotine. Possible genotoxic effects were determined by the Comet assay using the % DNA in tail (DT) as a reliable indicator of DNA damage. Nicotine induced a significant dose-dependent increase of DNA migration in parotid gland single-cells. The mean DT was 1.12-fold (0.125mM) to 2.24-fold (4.0mM) higher compared to control. The lowest concentration eliciting significant DNA damage within 1h, 0.25mM nicotine, is only 10-fold higher than maximal concentrations of nicotine reported in saliva after unrestricted smoking. Although conclusive evidence for a carcinogenic potential of nicotine is still lacking, the safety of long-term nicotine replacement therapy should be carefully monitored.

Three-dimensional mini organ cultures of human inferior nasal turbinate epithelia have proved to be a useful tool in genotoxicology studies. They allow repetitive or chronic exposure of cells to xenobiotics in a well-preserved organ-specific mucosal architecture for an extended period of time. It is the aim of the present study to concurrently monitor cumulative genotoxic and apoptotic effects of sodium dichromate, N-nitrosodiethylamine (NDEA) and N-methyl-N-nitro-N-nitroso-guanidine (MNNG). Mini organs were raised by separating fresh specimens of human inferior nasal turbinates (n=11) into 1 mm3 sized pieces and culturing them on multiwell plates with bronchial epithelial basal medium for 6 days. Aliquots of the mini organs were subsequently exposed to sodium dichromate (1.0 mM, 1h), NDEA (50 mM, 1h) or MNNG (0.07 mM, 1h) on days 7, 9 and 11 versus a single exposure on day 11 only. DNA fragmentation and apoptotic events were assessed on day 11 using the alkaline single cell microgel electrophoresis assay (comet assay) and the annexin V-affinity assay. Significant DNA fragmentation could be demonstrated after a single exposure of the mini organs to sodium dichromate. Following three subsequent incubations, there was a further increase in the genetic damage observed, accompanied by an increase in the rate of apoptotic cells. In contrast, after single and triple incubation with NDEA there was neither an increase in genetic damage nor in the fraction of apoptotic cells detectable. Repetitive exposure to MNNG resulted in an accumulation of DNA damage without an observable increase in apoptosis. The results verify the need to assess apoptosis in genotoxicology research and to investigate cumulative effects of xenobiotics. Three-dimensional mini organ cultures of human upper aerodigestive tract epithelia have shown to be well-suited for improving the ability to distinguish between cumulative genotoxic and apoptotic effects.