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•With 5 years of follow-up, nivolumab had lasting benefits in patients with R/R cHL after auto-HCT.•It appears feasible to discontinue nivolumab in patients with persistent CR and reinitiate treatment upon disease progression.

While it is experimentally supported that impaired myocardial vascularization contributes to a mismatch between myocardial oxygen demand and supply, a mechanistic basis for disruption of coordinated tissue growth and angiogenesis in heart failure remains poorly understood. Silencing strategies that impair microRNA biogenesis have firmly implicated microRNAs in the regulation of angiogenesis, and individual microRNAs prove to be crucial in developmental or tumor angiogenesis. A high-throughput functional screening for the analysis of a whole-genome microRNA silencing library with regard to their phenotypic effect on endothelial cell proliferation as a key parameter, revealed several anti- and pro-proliferative microRNAs. Among those was miR-216a, a pro-angiogenic microRNA which is enriched in cardiac microvascular endothelial cells and reduced in expression under cardiac stress conditions. miR-216a null mice display dramatic cardiac phenotypes related to impaired myocardial vascularization and unbalanced autophagy and inflammation, supporting a model where microRNA regulation of microvascularization impacts the cardiac response to stress.

Der Kompromiss ist eine Technik, mit der Konflikte über Zugeständnisse an konfligierende Sichtweisen und Positionen reguliert werden. Dass er in unterschiedlichen historischen wie gegenwärtigen gesellschaftlichen Kontexten ermöglicht, mit Konflikten umzugehen, macht ihn zu einem relevanten Gegenstand politikwissenschaftlicher wie geschichtswissenschaftlicher Forschung. Dieser Rezensionsaufsatz diskutiert aktuelle Literatur zum Thema aus beiden Disziplinen und fokussiert vier Themen: die Rolle von Kompromissen in Demokratien und Nicht-Demokratien, schlechte und gute Kompromisse, die historische Variabilität von Kompromissen sowie Voraussetzungen von Kompromissen.

ABSTRACTCalcium phosphates (CaPs) are extensively used as biomaterials for bone repair and regeneration and are considered an interesting synthetic alternative for natural bone grafts. However, the bone regenerative potential of many CaP bone graft substitutes requires further improvements. The bioactivity of CaPs is regulated by a variety of properties, including their chemical composition and (surface) structural properties. In this study, we performed a comprehensive characterization of six CaP ceramics that had been previously tested in several in vitro and in vivo studies, allowing us to in silico distinguish osteoinductive and non-osteoinductive CaP ceramics. The numerical parameters obtained from this characterization were further correlated with osteogenesis-associated gene expression and pathways of osteoblastic MG63 cells cultured on these six CaP ceramics. The results showed, among others, the influence of both chemical and structural parameters on cytoskeleton- and extracellular matrix-related gene expression and osteogenesis-associated pathways such as MAPK and BMP. The bioinformatics approach presented here allows exploring the transcriptional landscape induced by CaP ceramics and gaining fundamental knowledge about cell-biomaterial interactions.

The tenocyte niche contains biochemical and biophysical signals that are needed for tendon homeostasis. The tenocyte phenotype is correlated with cell shape in vivoand in vitro, and shape-modifying cues are needed for tenocyte phenotypical maintenance. Indeed, cell shape changes from elongated to spread when cultured on a flat surface, and rat tenocytes lose the expression of phenotypical markers throughout five passages. We hypothesized that tendon gene expression can be preserved by culturing cells in the native tendon shape. To this end, we reproduced the tendon topographical landscape into tissue culture polystyrene, using imprinting technology. We confirmed that the imprints forced the cells into a more elongated shape, which correlated with the level of Scleraxis expression. When we cultured the tenocytes for 7 days on flat surfaces and tendon imprints, we observed a decline in tenogenic marker expression on flat but not on imprints. This research demonstrates that native tendon topography is an important factor contributing to the tenocyte phenotype. Tendon imprints therefore provide a powerful platform to explore the effect of instructive cues originating from native tendon topography on guiding cell shape, phenotype, and function of tendon-related cells.

Membrane binding and unbinding dynamics play a crucial role in the biological activity of several nonintegral membrane proteins, which have to be recruited to the membrane to perform their functions. By localizing to the membrane, these proteins are able to induce downstream signal amplification in their respective signaling pathways. Here, we present a 3D computational approach using reaction-diffusion equations to investigate the relation between membrane localization of focal adhesion kinase (FAK), Ras homolog family member A (RhoA), and signal amplification of the YAP/TAZ signaling pathway. Our results show that the theoretical scenarios in which FAK is membrane bound yield robust and amplified YAP/TAZ nuclear translocation signals. Moreover, we predict that the amount of YAP/TAZ nuclear translocation increases with cell spreading, confirming the experimental findings in the literature. In summary, our in silico predictions show that when the cell membrane interaction area with the underlying substrate increases, for example, through cell spreading, this leads to more encounters between membrane-bound signaling partners and downstream signal amplification. Because membrane activation is a motif common to many signaling pathways, this study has important implications for understanding the design principles of signaling networks.

Glaucoma is a major eye disease characterized by a progressive loss of retinal ganglion cells (RGCs). Biomechanical forces as a result of hydrostatic pressure and strain play a role in this disease. Decreasing intraocular pressure is the only available therapy so far, but is not always effective and does not prevent blindness in many cases. There is a need for drugs that protect RGCs from dying in glaucoma; to develop these, we need valid glaucoma and drug screening models. Since in vivomodels are unsuitable for screening purposes, we focus on in vitroand ex vivomodels in this review. Many groups have studied pressure and strain model systems to mimic glaucoma, to investigate the molecular and cellular events leading to mechanically induced RGC death. Therefore, the focus of this review is on the different mechanical model systems used to mimic the biomechanical forces in glaucoma. Most models use either cell or tissue strain, or fluid- or gas-controlled hydrostatic pressure application and apply it to the relevant cell types such as trabecular meshwork cells, optic nerve head astrocytes, and RGCs, but also to entire eyes. New model systems are warranted to study concepts and test experimental compounds for the development of new drugs to protect vision in glaucoma patients.Impact StatementThe outcome of currently developed models to investigate mechanically induced retinal ganglion cell death by applying different mechanical strains varies widely. This suggests that a robust glaucoma model has not been developed yet. However, a comprehensive overview of current developments is not available. In this review, we have therefore assessed what has been done before and summarized the available knowledge in the field, which can be used to develop improved models for glaucoma research.

Background/objectives: Bile acids (BA) act as detergents in intestinal fat absorption and as modulators of metabolic processes viaactivation of receptors such as FXR and TGR5. Elevated plasma BA as well as increased intestinal BA signalling to promote GLP-1 release have been implicated in beneficial health effects of Roux-en-Y gastric bypass surgery (RYGB). Whether BA also contribute to the postprandial hypoglycaemia that is frequently observed post-RYGB is unknown. Methods: Plasma BA, fibroblast growth factor 19 (FGF19), 7α-hydroxy-4-cholesten-3-one (C4), GLP-1, insulin and glucose levels were determined during 3.5 h mixed-meal tolerance tests (MMTT) in subjects after RYGB, either with (RYGB, n= 11) or without a functioning gallbladder due to cholecystectomy (RYGB-CC, n= 11). Basal values were compared to those of age, BMI and sex-matched obese controls without RYGB (n= 22). Results: Fasting BA as well as FGF19 levels were elevated in RYGB and RYGB-CC subjects compared to non-bariatric controls, without significant differences between RYGB and RYGB-CC. Postprandial hypoglycaemia was observed in 8/11 RYGB-CC and only in 3/11 RYGB. Subjects who developed hypoglycaemia showed higher postprandial BA levels coinciding with augmented GLP-1 and insulin responses during the MMTT. The nadir of plasma glucose concentrations after meals showed a negative relationship with postprandial BA peaks. Plasma C4 was lower during MMTT in subjects experiencing hypoglycaemia, indicating lower hepatic BA synthesis. Computer simulations revealed that altered intestinal transit underlies the occurrence of exaggerated postprandial BA responses in hypoglycaemic subjects. Conclusion: Altered BA kinetics upon ingestion of a meal, as frequently observed in RYGB-CC subjects, appear to contribute to postprandial hypoglycaemia by stimulating intestinal GLP-1 release.

Breast implant–associated anaplastic large cell lymphoma (BIA-ALCL) is a very rare type of T-cell lymphoma that is uniquely caused by a single environmental stimulus. Here, we present a comprehensive genetic analysis of a relatively large series of BIA-ALCL (n = 29), for which genome-wide chromosomal copy number aberrations (CNAs) and mutational profiles for a subset (n = 7) were determined. For comparison, CNAs for anaplastic lymphoma kinase (ALK)−nodal anaplastic large cell lymphomas (ALCLs; n = 24) were obtained. CNAs were detected in 94% of BIA-ALCLs, with losses at chromosome 20q13.13 in 66% of the samples. Loss of 20q13.13 is characteristic of BIA-ALCL compared with other classes of ALCL, such as primary cutaneous ALCL and systemic type ALK+and ALK−ALCL. Mutational patterns confirm that the interleukin-6–JAK1–STAT3 pathway is deregulated. Although this is commonly observed across various types of T-cell lymphomas, the extent of deregulation is significantly higher in BIA-ALCL, as indicated by phosphorylated STAT3 immunohistochemistry. The characteristic loss of chromosome 20 in BIA-ALCL provides further justification to recognize BIA-ALCL as a separate disease entity. Moreover, CNA analysis may serve as a parameter for future diagnostic assays for women with breast implants to distinguish seroma caused by BIA-ALCL from other causes of seroma accumulation, such as infection or trauma.

Bile acids (BAs) facilitate intestinal absorption of lipid-soluble nutrients and modulate various metabolic pathways through the farnesoid X receptor (FXR) and Takeda G-protein-coupled receptor 5. These receptors are targets for therapy in cholestatic and metabolic diseases. However, dissimilarities in BA metabolism between humans and mice complicate translation of preclinical data. Cytochrome P450 family 2 subfamily c polypeptide 70 (CYP2C70) was recently proposed to catalyze the formation of rodent-specific muricholic acids (MCAs). With CRISPR/Cas9-mediated somatic genome editing, we generated an acute hepatic Cyp2c70knockout mouse model (Cyp2c70ako) to clarify the role of CYP2C70 in BA metabolism in vivo and evaluate whether its activity modulates effects of pharmacologic FXR activation on cholesterol homeostasis. In Cyp2c70akomice, chenodeoxycholic acid (CDCA) increased at the expense of βMCA, resulting in a more hydrophobic human-like BA pool. Tracer studies demonstrated that, in vivo, CYP2C70 catalyzes the formation of βMCA primarily by sequential 6β-hydroxylation and C7-epimerization of CDCA, generating αMCA as an intermediate metabolite. Physiologically, the humanized BA composition in Cyp2c70akomice blunted the stimulation of fecal cholesterol disposal in response to FXR activation compared with WT mice, predominantly due to reduced stimulation of transintestinal cholesterol excretion. Thus, deletion of hepatic Cyp2c70in adult mice translates into a human-like BA pool composition and impacts the response to pharmacologic FXR activation. This Cyp2c70akomouse model may be a useful tool for future studies of BA signaling and metabolism that informs human disease development and treatment.

Myeloid-derived suppressor cells (MDSCs) have the capacity to suppress T-cell–mediated immune responses and impact the clinical outcome of cancer, infections, and transplantation settings. Although MDSCs were initially described as bone marrow–derived immature myeloid cells (either monocytic or granulocytic MDSCs), mature neutrophils have been shown to exert MDSC activity toward T cells in ways that remain unclear. In this study, we demonstrated that human neutrophils from both healthy donors and cancer patients do not exert MDSC activity unless they are activated. By using neutrophils with genetically well-defined defects, we found that reactive oxygen species (ROS) and granule-derived constituents are required for MDSC activity after direct CD11b-dependent interactions between neutrophils and T cells. In addition to these cellular interactions, neutrophils are engaged in the uptake of pieces of T-cell membrane, a process called trogocytosis. Together, these interactions led to changes in T-cell morphology, mitochondrial dysfunction, and adenosine triphosphate depletion, as indicated by electron microscopy, mass spectrometry, and metabolic parameters. Our studies characterize the different steps by which activated mature neutrophils induce functional T-cell nonresponsiveness and irreparable cell damage.

Supplemental Digital Content is available in the text.

Patient Safety CME.

Microstructured light guiding plates (LGP) open up new capabilities in the design of energy efficient and flexible light sources for room lighting. One desirable application is the illumination of office rooms by LGPs located mainly at the façade. Starting with the requirements of an ideal light distribution curve for uniform room lighting, suitable optical microstructures have been designed and investigated by numerical ray tracing methods to be integrated in façade elements. The maximum of the desired light distribution curve for the test case is at an angle of 96° with respect to the vertical direction. The designed micro-system meets this requirement very well at an angle of 98° and a light cone width of 25°. The light emission of the proposed LGP is highly efficient with 80% coupling efficiency.

High-throughput screening of cell-biomaterial interactions combined with machine learning algorithms leads the way toward the future of medical device manufacturing: in silicomodeling of cell and tissue response. Bio-compatible medical implants will have a huge clinical impact.

Development of multicellular organisms is a highly orchestrated process, with cells responding to factors and features present in the extracellular milieu. Changes in the surrounding environment help decide the fate of cells at various stages of development. This review highlights recent research that details the effects of mechanical properties of the surrounding environment and extracellular matrix and the underlying molecular mechanisms that regulate the behavior of embryonic stem cells (ESCs). In this study, we review the role of mechanical properties during embryogenesis and discuss the effect of engineered microtopographies on ESC pluripotency.

We report 4 cases of breast cancer transmission to transplant recipients from a single organ donor that occurred years after donation. The diagnosis of breast cancer was occult at the time of donation. All of the recipients developed a histologically similar type of breast cancer within 16 months to 6 years after transplantation. Three out of 4 recipients died as a result of widely metastasized disease. One of the recipients survived after transplant nephrectomy followed by cessation of immunosuppression and chemotherapy. This extraordinary case points out the often fatal consequences of donor-derived breast cancer and suggests that removal of the donor organ and restoration of immunity can induce complete remission.

Biomaterials engineering is tightly linked with progress in its underlying sciences and technologies, such as biology, chemistry, physics, and engineering. Current establishment of high throughput screening platforms has warranted the need for data analysis as part of biomaterials engineering. We believe that current advancement in artificial intelligence, miniaturization of materials fabrication and application of robotics will eventually lead to the emergence of autonomous, intelligent systems able to perform biomaterials research on their own. In this manuscript, we describe the state of the art in the triangle of material engineering, biology, and data science, and sketch their integration to yield the biomaterials conveyer belt of tomorrow.

IMPORTANCE: Breast implants are among the most commonly used medical devices. Since 2008, the number of women with breast implants diagnosed with anaplastic large-cell lymphoma in the breast (breast-ALCL) has increased, and several reports have suggested an association between breast implants and risk of breast-ALCL. However, relative and absolute risks of breast-ALCL in women with implants are still unknown, precluding evidence-based counseling about implants. OBJECTIVE: To determine relative and absolute risks of breast-ALCL in women with breast implants. DESIGN, SETTING, AND PARTICIPANTS: Through the population-based nationwide Dutch pathology registry we identified all patients diagnosed with primary non-Hodgkin lymphoma in the breast between 1990 and 2016 and retrieved clinical data, including breast implant status, from the treating physicians. We estimated the odds ratio (OR) of ALCL associated with breast implants in a case-control design, comparing implant prevalence between women with breast-ALCL and women with other types of breast lymphoma. Cumulative risk of breast-ALCL was derived from the age-specific prevalence of breast implants in Dutch women, estimated from an examination of 3000 chest x-rays and time trends from implant sales. MAIN OUTCOMES AND MEASURES: Relative and absolute risks of breast-ALCL in women with breast implants. RESULTS: Among 43 patients with breast-ALCL (median age, 59 years), 32 had ipsilateral breast implants, compared with 1 among 146 women with other primary breast lymphomas (OR, 421.8; 95% CI, 52.6-3385.2). Implants among breast-ALCL cases were more often macrotextured (23 macrotextured of 28 total implants of known type, 82%) than expected (49 193 sold macrotextured implants of total sold 109 449 between 2010 and 2015, 45%) based on sales data (P < .001). The estimated prevalence of breast implants in women aged 20 to 70 years was 3.3%. Cumulative risks of breast-ALCL in women with implants were 29 per million at 50 years and 82 per million at 70 years. The number of women with implants needed to cause 1 breast-ALCL case before age 75 years was 6920. CONCLUSIONS AND RELEVANCE: Breast implants are associated with increased risk of breast-ALCL, but the absolute risk remains small. Our results emphasize the need for increased awareness among the public, medical professionals, and regulatory bodies, promotion of alternative cosmetic procedures, and alertness to signs and symptoms of breast-ALCL in women with implants.

Chemical and mechanical cues are well-established influencers of in vitrochondrogenic differentiation of ATDC5 cells. Here, we investigate the role of topographical cues in this differentiation process, a study not been explored before. Previously, using a library of surface micro-topographies we found some distinct patterns that induced alkaline phosphatase (ALP) production in human mesenchymal stromal cells. ALPis also a marker for hypertrophy, the end stage of chondrogenic differentiation preceding bone formation. Thus, we hypothesized that these patterns could influence end-stage chondrogenic differentiation of ATDC5 cells. In this study, we randomly selected seven topographies among the ALPinfluencing hits. Cells grown on these surfaces displayed varying nuclear shape and actin filament structure. When stimulated with insulin-transferrin-selenium (ITS) medium, nodule formation occurred and in some cases showed alignment to the topographical patterns. Gene expression analysis of cells growing on topographical surfaces in the presence of ITS medium revealed a downregulation of early markers and upregulation of late markers of chondrogenic differentiation compared to cells grown on a flat surface. In conclusion, we demonstrated that surface topography in addition to other cues can promote hypertrophic differentiation suitable for bone tissue engineering.

Supplemental Digital Content is available in the text.

Statins are competitive inhibitors of HMG-CoA reductase, the rate-limiting enzyme of cholesterol synthesis. Statins reduce plasma cholesterol levels, but whether this is actually caused by inhibition of de novo cholesterol synthesis has not been clearly established. Using three different statins, we investigated the effects on cholesterol metabolism in mice in detail. Surprisingly, direct measurement of whole body cholesterol synthesis revealed that cholesterol synthesis was robustly increased in statin-treated mice. Measurement of organ-specific cholesterol synthesis demonstrated that the liver is predominantly responsible for the increase in cholesterol synthesis. Excess synthesized cholesterol did not accumulate in the plasma, as plasma cholesterol decreased. However, statin treatment led to an increase in cholesterol removal via the feces. Interestingly, enhanced cholesterol excretion in response to rosuvastatin and lovastatin treatment was mainly mediated via biliary cholesterol secretion, whereas atorvastatin mainly stimulated cholesterol removal via the transintestinal cholesterol excretion pathway. Moreover, we show that plasma cholesterol precursor levels do not reflect cholesterol synthesis rates during statin treatment in mice. In conclusion, cholesterol synthesis is paradoxically increased upon statin treatment in mice. However, statins potently stimulate the excretion of cholesterol from the body, which sheds new light on possible mechanisms underlying the cholesterol-lowering effects of statins.

While subcutaneous tissue has been proposed as a clinically relevant site for pancreatic islet transplantation, a major issue of concern remains, which is its poor vascular state. In an effort to overcome this limitation, we present an efficient and reproducible method to form human composite islets (CIs) with proangiogenic cell types in a controlled manner using nonadherent agarose microwell templates. In this study, we assessed the three-dimensional structure, function, and angiogenic potential of human CIs with human mesenchymal stromal cells (hMSCs), with or without human umbilical vein endothelial cells (HUVECs), and preconditioned hMSCs (PC-hMSCs) in EGM-2 under shear stress. Distinct cellular rearrangements could be observed in CIs, but islet functionality was maintained. In vitroangiogenesis assays found significantly enhanced sprout formation in case of CIs. In particular, the number of sprouts emanating from CIs with PC-hMSCs was significantly increased compared to other conditions. Subsequent in vivoassessment confirmed the proangiogenic potential of CIs. However, in contrast to our in vitroangiogenesis assays, CIs with hMSCs and HUVECs exhibited a higher in vivoangiogenic potential compared to control islets or islets combined with hMSCs or PC-hMSCs. These findings highlight the importance and necessity of verifying in vitrostudies with in vivomodels to reliably predict, in this case, revascularization outcomes. Regardless, we demonstrate here the therapeutic potential of CIs with proangiogenic support cells to enhance islet revascularization at a clinically relevant, although poorly vascularized, transplantation site.

IMPORTANCE: Patients with head and neck cancer may experience chemoradiotherapy-induced hearing loss, but the weighing of involved variables has been subjective. Identification of patient and treatment characteristics to predict the absolute posttreatment hearing level is important for effective counseling of patients undergoing chemoradiotherapy. OBJECTIVE: To predict treatment-induced hearing loss among patients with head and neck cancer. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort study was performed at The Netherlands Cancer Institute. One hundred and fifty-six patients with head and neck cancer treated with concomitant chemoradiotherapy as the primary treatment modality from January 1, 1997, through December 31, 2011, were enrolled. Follow-up was complete on March 1, 2012, and data were analyzed from April 1, 2011, through November 5, 2013. INTERVENTIONS: High-dose intravenously administered cisplatin-based concomitant chemoradiotherapy. Cisplatin, 100 mg/m2, was administered in 3 courses on days 1, 22, and 43 during 7 weeks of radiotherapy (total radiation dose, 70 Gy in 35 fractions). MAIN OUTCOMES AND MEASURES: Posttreatment bone conduction hearing threshold at pure-tone average frequencies of 1, 2, and 4 kHz, based on pure-tone audiometry after completion of treatment. Predictors included baseline hearing levels, radiation dose to the cochlea, and cisplatin dose. A multilevel mixed-effects linear regression model for predicting whether or not posttreatment hearing was at least 35 dB was established, and cross-validated sensitivity and specificity were obtained. RESULTS: Of 156 patients who received high-dose concomitant chemoradiotherapy, 15 were missing the exact radiation dose to the cochlea and 41 had no data on posttreatment pure-tone audiometry. Nineteen patients had a hearing level of at least 35 dB for at least 1 ear before the treatment. The remaining 81 patients (162 ears) had a total cumulative cisplatin dose ranging from 315 to 600 (median, 546) mg. The radiation dose to the cochlea ranged from 1.1 to 70.9 (median, 13.6) Gy. Based on data from the 81 patients (162 ears), the area under the receiver operating characteristic curve was 0.68, with a sensitivity of 29% (95% CI, 13%-51%) and a specificity of 97% (95% CI, 88%-100%), resulting in a positive predictive value of 78%. CONCLUSIONS AND RELEVANCE: Patient and treatment characteristics can be used to predict hearing level after concomitant chemoradiotherapy for head and neck cancer. This step may constitute the first in evidence-based individual counseling for treatment-induced hearing loss.

Extracellular matrix (ECM) provides not only structural support to the cells but also signals that regulate their fate. In many tissue engineering approaches, it remains challenging to achieve the right amount and type of ECM secreted by the cells to faithfully mimic the native tissue. In this article, we describe how to design and perform a high-throughput assay to screen for molecules capable of enhancing collagenous ECM (cECM) production. We chose ATDC5 cells to validate the assay since we want to use this chondrogenic cell line later for tissue engineering of hypertrophic cartilage. We used a fluorescently labeled collagen-binding probe to quantify total collagen content in ATDC5 cultures. The LOPAC1280library of pharmaceutically active compounds was screened using insulin (a known inducer of cECM in ATDC5 cells) as positive control. After screening and validation, the small-molecule tetradecylthioacetic acid (TTA) was shown to enhance cECM production by ATDC5 cells at both gene expression and protein level. Moreover, when combined with insulin, TTA showed a synergistic effect on cECM production. In contrast, exposure of human primary chondrocytes and human mesenchymal stromal cells to TTA did not induce cECM secretion. In conclusion, we have developed an HTS assay to screen for compounds capable of enhancing cECM production and discovered TTA as a potent enhancer of cECM secretion by ATDC5 cells.

One version of the membrane paradigm states that, as far as outside observers are concerned, black holes can be replaced by a dissipative membrane with simple physical properties located at the stretched horizon. We demonstrate that such a membrane paradigm is incomplete in several aspects. We argue that it generically fails to capture the massive quasinormal modes, unless we replace the stretched horizon by the exact event horizon, and illustrate this with a scalar field in a Banados-Teitelboim-Zanelli (BTZ) black hole background. We also consider as a concrete example linearized metric perturbations of a five-dimensional AdS-Schwarzschild black brane and show that a spurious excitation appears in the long-wavelength response that is only removed from the spectrum when the membrane paradigm is replaced by ingoing boundary conditions at the event horizon. We interpret this excitation in terms of an additional Goldstone boson that appears due to symmetry breaking by the classical solution ending on the stretched horizon rather than the event horizon. [ABSTRACT FROM AUTHOR]

In differentiated cells, aging is associated with hypermethylation of DNA regions enriched in repressive histone post-translational modifications. However, the chromatin marks associated with changes in DNA methylation in adult stem cells during lifetime are still largely unknown. Here, DNA methylation profiling of mesenchymal stem cells (MSCs) obtained from individuals aged 2 to 92 yr identified 18,735 hypermethylated and 45,407 hypomethylated CpG sites associated with aging. As in differentiated cells, hypermethylated sequences were enriched in chromatin repressive marks. Most importantly, hypomethylated CpG sites were strongly enriched in the active chromatin mark H3K4me1 in stem and differentiated cells, suggesting this is a cell type–independent chromatin signature of DNA hypomethylation during aging. Analysis of scedasticity showed that interindividual variability of DNA methylation increased during aging in MSCs and differentiated cells, providing a new avenue for the identification of DNA methylation changes over time. DNA methylation profiling of genetically identical individuals showed that both the tendency of DNA methylation changes and scedasticity depended on nongenetic as well as genetic factors. Our results indicate that the dynamics of DNA methylation during aging depend on a complex mixture of factors that include the DNA sequence, cell type, and chromatin context involved and that, depending on the locus, the changes can be modulated by genetic and/or external factors.

Radiation to the inner ear may lead to (irreversible) sensorineural hearing loss. The purpose of this study was to evaluate the long-term effect of radiotherapy on hearing in patients treated with Intensity Modulated Radiation Therapy (IMRT), sparing the inner ear from high radiation dose as much as possible. Between 2003 and 2006, 101 patients with head and neck cancer were treated with IMRT. Audiometry was performed before, short-term, and long-term after treatment. Data were compared to normal hearing levels according to the International Organisation for Standardization (ISO). Statistical analysis was done using repeated measurements. None of the patients received chemotherapy. In 36 patients an audiogram at long-term follow-up (median 7.6 years) was available. The mean dose to the cochlea was 17.8 Gy (1.0-66.6 Gy). A hearing deterioration of 1.8 dB at Pure Tone Average (PTA) 0.5-1-2 kHz (p= 0.11), 2.3 dB at PTA 1-2-4 kHz (p= 0.02), and 4.4 dB at PTA 8-10-12.5 kHz (p= 0.01) was found. According to the ISO, the expected age-related hearing loss was 2.7, 4.8, and 8.8 dB at PTA 0.5-1-2 kHz, 1-2-4 kHz, and 8-10-12.5 kHz, respectively. After IMRT with radiation dose constraint to the cochlea, potential long-term adverse effects of IMRT remained subclinical. The progressive hearing loss over time was mild and could be attributed to the natural effects of ageing. Therefore, we recommend that a dose constraint to the cochlea should be incorporated in the head and neck radiotherapy protocols.

Objective:This study aimed to propose an ototoxicity grading system sensitive to the effect of ototoxicity on specific daily life situations like speech intelligibility and the perception of ultra-high sounds and to test its feasibility compared to current criteria.Methods:Pure tone averages (PTAs) for speech perception (1-2-4 kHz) and ultra-high frequencies (8-10-12.5 kHz) were incorporated. Threshold shift and hearing level posttreatment were taken into account. Criteria were tested on head and neck cancer patients treated with (chemo-)radiotherapy ([C]RT) and compared with the Common Terminology Criteria for Adverse Events version 4 (CTCAEv4) and the American Speech-Language-Hearing Association criteria (ASHA).Results:Grades 1 and 2 were based on threshold shifts from baseline (in dB) and subjective complaints. Grades 3 and 4 were defined as treatment-induced hearing loss of ≥ 35 dB at PTA 1-2-4 kHz and ≥ 70 dB at PTA 1-2-4 kHz, respectively. In high-dose cisplatin CRT incidences by the new criteria, CTCAEv4 and ASHA were comparable (78%-88%). In RT and low-dose cisplatin CRT, incidences were 36% to 39% in the new criteria versus 22% to 53% in CTCAEv4 and ASHA.Conclusion:The new criteria show an increased sensitivity to ototoxicity compared to CTCAEv4 and ASHA and provide insight into the effect of hearing loss on certain daily life situations. The new grading system seems feasible for clinic and research purposes.

We assessed risk, localization, and timing of third malignancies in Hodgkin lymphoma (HL) survivors. In a cohort of 3122 5-year HL survivors diagnosed before the age of 51 years and treated between 1965 and 1995, we examined whether risk factors for second and third malignancies differ and whether the occurrence of a second malignancy affects the risk of subsequent malignancies, using recurrent event analyses. After a median follow-up of 22.6 years, 832 patients developed a second malignancy and 126 patients a third one. The risk of a second malignancy was 4.7-fold increased (95% confidence interval [CI], 4.4-5.1) compared with risk in the general population; the risk for a third malignancy after a second malignancy was 5.4-fold (95% CI, 4.4-6.5) increased. The 10-year cumulative incidence of any third malignancy was 13.3%. Compared with patients still free of a second malignancy, patients with a second malignancy had a higher risk of developing subsequent malignancies. This risk depended on age, with hazard ratios of 2.2, 1.6, and 1.1 for patients aged <25, 25 to 34, and 35 to 50 years at HL treatment, respectively. In HL survivors who had a second malignancy, treating physicians should be aware of the increased risk of subsequent malignancies.

Because apoB-containing lipoproteins are pro-atherogenic and their secretion by liver and intestine largely depends on microsomal triglyceride transfer protein (MTP) activity, MTP inhibition strategies are actively pursued. How decreasing the secretion of apoB-containing lipoproteins affects intracellular rerouting of cholesterol is unclear. Therefore, the aim of the present study was to determine the effects of reducing either systemic or liver-specific MTP activity on cholesterol metabolism and reverse cholesterol transport (RCT) using a pharmacological MTP inhibitor or a genetic model, respectively. Plasma total cholesterol and triglyceride levels were decreased in both MTP inhibitor-treated and liver-specific MTP knockout (L-Mttp−/−) mice (each P< 0.001). With both inhibition approaches, hepatic cholesterol as well as triglyceride content was consistently increased (each P< 0.001), while biliary cholesterol and bile acid secretion remained unchanged. A small but significant decrease in fecal bile acid excretion was observed in inhibitor-treated mice (P< 0.05), whereas fecal neutral sterol excretion was substantially increased by 75% (P< 0.001), conceivably due to decreased intestinal absorption. In contrast, in L-Mttp−/−mice both fecal neutral sterol and bile acid excretion remained unchanged. However, while total RCT increased in inhibitor-treated mice (P< 0.01), it surprisingly decreased in L-Mttp−/−mice (P< 0.05). These data demonstrate that: i) pharmacological MTP inhibition increases RCT, an effect that might provide additional clinical benefit of MTP inhibitors; and ii) decreasing hepatic MTP decreases RCT, pointing toward a potential contribution of hepatocyte-derived VLDLs to RCT.

Angiogenesis and neovascularization are fundamental for the success of clinically relevant-sized tissue-engineered (TE) constructs. The next generation of TE constructs relies on providing instructive materials combined with the delivery of angiogenic growth factors and cells to avoid tissue ischemia. However, the majority of materials and cell types screened so far show limited clinical relevance, either due to insufficient number of cells or due to the use of animal-derived matrixes. Here, we investigated whether endothelial-like cells derived from mesenchymal stromal cells (EL-MSCs) can be used for vascular TE in combination with injectable dextran–hyaluronic acid (Dex-g-HA) hydrogels. These hydrogels can be easily modified, as demonstrated by the incorporation of vascular endothelial growth factor (VEGF). We examined in vitrothe reciprocal influences between cells and matrix. Dex-g-HA enabled higher EL-MSC metabolic rates associated with optimal cell sprouting in vitrocompared to human umbilical vein endothelial cells. In vivoevaluation demonstrated the absence of an acute inflammatory response, and EL-MSCs incorporated within Dex-g-HA formed a functional vascular network integrated with the host vascular system. This work demonstrates that Dex-g-HA is an efficient delivery method of VEGF to induce angiogenesis. Additionally, functional neovascularization can be achieved in vitroand in vivoby the combination of Dex-g-HA with EL-MSC.

Application of autologous cells is considered for a broad range of regenerative therapies because it is not surrounded by the immunological and ethical issues of allo- or xenogenic cells. However, isolation, expansion, and application of autologous cells do suffer from variability in therapeutic efficacy due to donor to donor differences and due to prolonged culture. One important source of autologous cells is mesenchymal stromal cells (MSCs), which can differentiate toward endothelial-like cells, thus making them an ideal candidate as cell source for tissue vascularization. Here we screened MSCs from 20 donors for their endothelial differentiation capacity and correlated it with the gene expression profile of the whole genome in the undifferentiated state. Cells of all donors were able to form tubes on Matrigel and induced the expression of endothelial genes, although with quantitative differences. In addition, we analyzed the effect of prolonged in vitroexpansion on the multipotency of human MSCs and found that endothelial differentiation is only mildly sensitive to expansion-induced loss of differentiation as compared to osteogenic and adipogenic differentiation. Our results show the robustness of the endothelial differentiation protocol and the gene expression data give insight in the differences in endothelial differentiation between donors.

Human mesenchymal stromal cells (hMSCs) offer great potential for bone tissue engineering applications, but their in vivoperformance remains limited. Preconditioning of these cells with small molecules to improve their differentiation before implantation, or incorporation of growth factors are possible solutions. Insulin-like growth factor-1 (IGF-1) is one of the most abundant growth factors in bone, involved in growth, development, and metabolism, but its effects on hMSCs are still subject of debate. Here we examined the effects of IGF-1 on proliferation and differentiation of hMSCs in vitroand we found that serum abolished the effects of IGF-1. Only in the absence of serum, IGF-1 increased proliferation, alkaline phosphatase expression, and osteogenic gene expression of hMSCs. Furthermore, we examined synergistic effects of bone morphogenetic protein-2 (BMP-2) and IGF-1 and, although IGF-1 enhanced BMP-2-induced mineralization, IGF-1 only slightly affected in vivobone formation.

Bone marrow-derived multipotent mesenchymal stromal cells (MSCs) are the most frequently investigated cell type for potential regenerative strategies because they are relatively easy to isolate and are able to differentiate into several mesenchymal lineages. Unfortunately, during ex vivoculture, MSCs present gradual loss of differentiation potential and reduced clinical efficacy. Reactive oxygen species (ROS) are associated with oxidative damage and accumulate during MSC expansion. Because ROS are believed to be involved in the loss of multipotency, we hypothesized that compounds with antioxidant activity have the capacity to scavenge ROS, prevent cellular damage, and rescue culture-induced loss of multipotency. In this manuscript, we show that antioxidant supplementation can partially rescue the loss of alkaline phosphatase expression induced by oxidizing agents and increases the yield of hMSCs, when supplemented to a fresh bone marrow aspirate. Concomitantly, oxidative DNA damage and ROS levels in hMSCs were reduced by antioxidants. We conclude that antioxidant supplementation during MSC expansion reduces the DNA damage load and increases the MSC yield.

Large-Nc QCD matter at intermediate baryon density and low temperatures has been conjectured to be in the so-called quarkyonic phase, i.e., to have a quark Fermi surface and on top of it a confined spectrum of excitations. It has been suggested that the presence of the quark Fermi surface leads to a homogeneous phase with restored chiral symmetry, which is unstable towards creating condensates that break both the chiral and translational symmetry. Motivated by these exotic features, we investigate properties of cold baryonic matter in the single-flavor Sakai-Sugimoto model, searching for a holographic realization of the quarkyonic phase. We use a simplified mean-field description and focus on the regime of parametrically large baryon densities, of the order of the square of the 't Hooft coupling, as they turn out to lead to new physical effects similar to the ones occurring in the quarkyonic phase. One effect--the appearance of a particular marginally stable mode breaking translational invariance and linked with the presence of the Chem-Simons term in the flavor-brane Lagrangian--is known to occur in the deconfined phase of the Sakai-Sugimoto model, but turns out to be absent here. The other, completely new phenomenon that we, preliminarily, study using strong simplifying assumptions are density-enhanced interactions of the flavorbrane gauge field with holographically represented baryons. These seem to significantly affect the spectrum of vector and axial mesons and might lead to approximate chiral symmetry restoration in the lowest part of the spectrum, where the mesons start to qualitatively behave like collective excitations of the dense baryonic medium. We discuss the relevance of these effects for holographic searches of the quarkyonic phase and conclude with a discussion of various subtleties involved in constructing a mean- field holographic description of a dense baryonic medium. [ABSTRACT FROM AUTHOR]

There is a rise in the popularity of arthroscopic procedures in orthopedics. However, the majority of cell-based bone tissue-engineered constructs (TECs) rely on solid preformed scaffolding materials, which require large incisions and extensive dissections for placement at the defect site. Thus, they are not suitable for minimally invasive techniques. The aim of this study was to develop a clinically relevant, easily moldable, bone TEC, amenable to minimally invasive techniques, using human mesenchymal stromal cells (hMSCs) and calcium phosphate microparticles in combination with an in situforming platelet-rich plasma gel obtained from human platelets. Most conventional TECs rely on seeding and culturing single-cell suspensions of hMSCs on scaffolds. However, for generating TECs amenable to the minimally invasive approach, it was essential to aggregate the hMSCs in vitrobefore seeding them on the scaffolds as unaggregated MSCs did not generate any bone. Twenty four hours of in vitroaggregation was determined to be optimal for maintaining cell viability in vitroand bone formation in vivo. Moreover, no statistically significant difference was observed in the amount of bone formed when the TECs were implanted via an open approach or a minimally invasive route. TECs generated using MSCs from three different human donors generated new bone through the minimally invasive route in a reproducible manner, suggesting that these TECs could be a viable alternative to preformed scaffolds employed through an open surgery for treating bone defects.

Osteogenic differentiation of human mesenchymal stromal cells (hMSCs) may potentially be used in cell-based bone tissue-engineering applications to enhance the bone-forming potential of these cells. Osteogenic differentiation and adipogenic differentiation are thought to be mutually exclusive, and although several signaling pathways and cues that induce osteogenic or adipogenic differentiation, respectively, have been identified, there is no general consensus on how to optimally differentiate hMSCs into the osteogenic lineage. Some pathways have also been reported to be involved in both adipogenic and osteogenic differentiation, as for example, the protein kinase A (PKA) pathway, and the aim of this study was to investigate the role of cAMP/PKA signaling in differentiation of hMSCs in more detail. We show that activation of this pathway with dibutyryl-cAMP results in enhanced alkaline phosphatase expression, whereas another cAMP analog induces adipogenesis in long-term mineralization cultures. Adipogenic differentiation, induced by 8-bromo-cAMP, was accompanied by stronger PKA activity and higher expression of cAMP-responsive genes, suggesting that stronger activation correlates with adipogenic differentiation. In addition, a whole-genome expression analysis showed an increase in expression of adipogenic genes in 8-br-cAMP-treated cells. Furthermore, by means of quantitative polymerase chain reaction, we show differences in peroxisome proliferator-activated receptor-γ activation, either alone or in combination with dexamethasone, thus demonstrating differential effects of the PKA pathway, most likely depending on its mode of activation.

OBJECTIVE To evaluate the functional outcomes after total laryngectomy (TLE) for a dysfunctional larynx in patients with head and neck cancer that is in complete remission after (chemo)radiotherapy. DESIGN Retrospective cohort study. SETTING Tertiary comprehensive cancer center. PATIENTS The study included 25 patients from a cohort of 217 consecutive patients with TLE who were treated between January 2000 and July 2010. The inclusion criteria for this subgroup analysis were complete remission and functional problems for which TLE was considered to be the only resolution. Quality of life assessment was carried out using the European Organization for Research and Treatment of Cancer Quality of Life C30 and Head and Neck Module 35 questionnaires and an additional study-specific questionnaire covering functional aspects, such as swallowing and dyspnea, in more detail. INTERVENTION Total laryngectomy. MAIN OUTCOME MEASURES Morbidity, mortality, and functional outcomes. RESULTS The indication for TLE was chronic aspiration with or without recurrent pneumonia (n = 15 [60%]), debilitating dyspnea (n = 8 [32%]), and persistent profuse hemorrhage (radiation ulcer) (n = 2 [8%]). After TLE, 14 of the 25 patients (56%) had 20 major postoperative complications, including 11 pharyngocutaneous fistulas, requiring additional treatment. Tube feeding and recurrent pneumonia incidence had decreased from 80% and 28% to 29% and 0%, respectively, 2 years after surgery. Prosthetic voice rehabilitation was possible in 19 patients (76%). Two years after surgery, 10 of 14 patients (71%) still reported TLE-related pulmonary problems despite the consistent use of a heat and moisture exchanger. The 5-year overall survival rate was 35%. CONCLUSIONS Total laryngectomy for a dysfunctional larynx tends to have a high complication rate. However, in this study, the initial functional problems (aspiration, recurrent pneumonia, and dyspnea) did not recur. Tube feeding was significantly reduced, and the quality of life of the surviving patients appeared to be reasonable.

ApoE plays an important role in lipoprotein metabolism. This study investigated the effects of adenovirus-mediated human apoE overexpression (AdhApoE3) on sterol metabolism and in vivo reverse cholesterol transport (RCT). In wild-type mice, AdhApoE3 resulted in decreased HDL cholesterol levels and a shift toward larger HDL in plasma, whereas hepatic cholesterol content increased (P < 0.05). These effects were dependent on scavenger receptor class B type I (SR-BI) as confirmed using SR-BI-deficient mice. Kinetic studies demonstrated increased plasma HDL cholesteryl ester catabolic rates (P < 0.05) and higher hepatic selective uptake of HDL cholesteryl esters in AdhApoE3-injected wild-type mice (P < 0.01). However, biliary and fecal sterol output as well as in vivo macrophage-to-feces RCT studied with 3H-cholesterol-loaded mouse macrophage foam cells remained unchanged upon human apoE overexpression. Similar results were obtained using hApoE3 overexpression in human CETP transgenic mice. However, blocking ABCA1-mediated cholesterol efflux from hepatocytes in AdhApoE3-injected mice using probucol increased biliary cholesterol secretion (P < 0.05), fecal neutral sterol excretion (P < 0.05), and in vivo RCT (P < 0.01), specifically within neutral sterols. These combined data demonstrate that systemic apoE overexpression increases i) SR-BI-mediated selective uptake into the liver and ii) ABCA1-mediated efflux of RCT-relevant cholesterol from hepatocytes back to the plasma compartment, thereby resulting in unchanged fecal mass sterol excretion and overall in vivo RCT.

The article provides information on a study conducted to describe the low energy excitation of R-charged ADS5 black holes. The finite extremal black holes having horizon geometry with ADFS2 factor show the association between Virasoro algebra with geometry of black holes. A difference in the local ADS3 and potential of infrared two-dimensional conformal field theory has been detected near biophysical setting (BPS) and non-BPS regimes.