Gemcitabine as chemotherapy of head and neck cancer in Fanconi anemia patients.

Fanconi anemia (FA) is a rare hereditary disease resulting from an inactivating mutation in the FA/BRCA pathway, critical for the effective repair of DNA interstrand crosslinks (ICLs). The disease is characterized by congenital abnormalities, progressing bone marrow failure, and an increased risk of developing malignancies early in life, in particular head and neck squamous cell carcinoma (HNSCC). While ICL-inducing cisplatin combined with radiotherapy is a mainstay of HNSCC treatment, cisplatin is contra-indicated for FA-HNSCC patients. This dilemma necessitates the identification of novel treatment modalities tolerated by FA-HNSCC patients. To identify druggable targets, an siRNA-based genetic screen was previously performed in HNSCC-derived cell lines from FA and non-FA tumor origin. Here, we report that the Ribonucleotide Reductase (RNR) complex, consisting of the RRM1 and RRM2 subunits, was identified as a therapeutic target for both, FA and non-FA HNSCC. While non-FA HNSCC cells responded differentially to RNR depletion, FA-HNSCC cells were consistently found hypersensitive. This insight was confirmed pharmacologically using 2', 2'-difluoro 2'deoxycytidine (dFdC), also known as gemcitabine, a clinically used nucleotide analog that is a potent inhibitor of the RNR complex. Importantly, while cisplatin exposure displayed severe, long-lasting toxicity on the hematopoietic stem and progenitor compartments in Fancg-/- mice, gemcitabine was well tolerated and had only a mild, transient impact. Taken together, our data implicate that gemcitabine-based chemoradiotherapy could serve as an alternative HNSCC treatment in Fanconi patients, and deserves clinical testing.

Predicting the bodily self in space and time.

To understand how the human brain distinguishes itself from external stimulation, it was examined if motor predictions enable healthy adult volunteers to infer self-location and to distinguish their body from the environment (and other agents). By uniquely combining a VR-setup with full-body motion capture, a full-body illusion paradigm (FBI) was developed with different levels of motion control: (A) a standard, passive FBI in which they had no motion control; (B) an active FBI in which they made simple, voluntary movements; and (C) an immersive game in which they real-time controlled a human-sized avatar in third person. Systematic comparisons between measures revealed a causal relationship between (i) motion control (prospective agency), (ii) self-other identification, and (iii) the ability to locate oneself. Healthy adults could recognise their movements in a third-person avatar and psychologically align with it (action observation); but did not lose a sense of place (self-location), time (temporal binding), nor who they are (self/other). Instead, motor predictions enabled them to localise their body and to distinguish self from other. In the future, embodied games could target and strengthen the brain's control networks in psychosis and neurodegeneration; real-time motion simulations could help advance neurorehabilitation techniques by fine-tuning and personalising therapeutic settings.

LIVE-streaming 3D images: A neuroscience approach to full-body illusions.

Inspired by recent technological advances in the gaming industry, we used capture cards to create and LIVE-stream high quality 3D-images. With this novel technique, we developed a real-life stereoscopic 3D full-body illusion paradigm (3D projection). Unlike previous versions of the full-body illusion that rely upon unwieldy head-mounted displays, this paradigm enables the unobstructed investigation of such illusions with neuroscience methods (e.g., transcranial direct current stimulation, transcranial magnetic stimulation, electroencephalography, and near-infrared spectroscopy) and examination of their neural underpinnings. This paper has three aims: (i) to provide a step-by-step guide on how to implement 3D LIVE-streaming, (ii) to explain how this can be used to create a full-body illusion paradigm; and (iii) to present evidence that documents the effectiveness of our methods (de Boer et al., 2020), including suggestions for potential applications. Particularly significant is the fact that 3D LIVE-streaming is not GPU-intensive and can easily be applied to any device or screen that can display 3D images (e.g., TV, tablet, mobile phone). Therefore, these methods also have potential future clinical and commercial benefits. 3D LIVE-streaming could be used to enhance future clinical observations or educational tools, or potentially guide medical interventions with real-time high-quality 3D images. Alternatively, our methods can be used in future rehabilitation programs to aid recovery from nervous system injury (e.g., spinal cord injury, brain damage, limb loss) or in therapies aimed at alleviating psychosis symptoms. Finally, 3D LIVE-streaming could set a new standard for immersive online gaming as well as augmenting online and mobile experiences (e.g., video chat, social sharing/events).

Design and characterisation of frequency selective conductive materials for electromagnetic fields control.

To prevent the electromagnetic (EM) wakefields excitation, protect detectors from damage at a range of installations and facilities including particle accelerators the EM field control is required. Conductive foils or wires providing EM protection and required thermal and mechanical properties are normally used. We suggest novel composite materials with uniquely designed frequency selective conductivity enabling them to overcome the properties of the conventional materials, protect from EM fields and supress undesirable phenomena. Theoretical and experimental investigations are carried out and the conductivity of designed and composite (dual-layer) aluminium/graphene metamaterials as well as graphene and aluminium foils is studied. The EM properties of these materials are compared, and conditions of full and partial electromagnetic transparency are discussed. Results observed allow engineering materials capable of EM field control, instability suppression including those observed in high-intensity particle accelerators and enabling control of an EM field generating media including relativistic charge particle beams.

A causal role for the right angular gyrus in self-location mediated perspective taking.

Recent theories suggest that self-consciousness, in its most elementary form, is functionally disconnected from the phenomenal body. Patients with psychosis frequently misattribute their thoughts and actions to external sources; and in certain out-of-body experiences, lucid states, and dreams body-ownership is absent but self-identification is preserved. To explain these unusual experiences, we hypothesized that self-identification depends on inferring self-location at the right angular gyrus (i.e., perspective-taking). This process relates to the discrimination of self-produced signals (endogenous attention) from environmental stimulation (exogenous attention). Therefore, when this mechanism fails, this causes altered sensations and perceptions. We combined a Full-body Illusion paradigm with brain stimulation (HD-tDCS) and found a clear causal association between right angular gyrus activation and alterations in self-location (perspective-taking). Anodal versus sham HD-tDCS resulted in: a more profound out-of-body shift (with reduced sense of agency); and a weakened ability to discriminate self from other perspectives. We conclude that self-identification is mediated in the brain by inferring self-location (i.e., perspective-taking). Self-identification can be decoupled from the bodily self, explaining phenomena associated with disembodiment. These findings present novel insights into the relationship between mind and body, and may offer important future directions for treating psychosis symptoms and rehabilitation programs to aid in the recovery from a nervous system injury. The brain's ability to locate itself might be the key mechanism for self-identification and distinguishing self from other signals (i.e., perspective-taking).

Beam impedance minimization for accelerator beamline insertion devices.

Use of complex state-of-the art detectors and monitors is essential to carry out high-energy and nuclear physics experiments at accelerator/collider facilities. The detectors are used to monitor charged particle beam parameters at large accelerator facilities such as coherent light sources and to develop new state-of-the art accelerators. Improvements in beam quality and lifetime necessitate the advancement of the instrumentation for successful operation of the accelerator facilities. Minimization of the beam-line-inserted devices' influence on the beam is therefore one of the essential considerations during the design of such facilities and the preparation of experiments. In this paper, we suggest and discuss a roadmap to minimize this influence. It is developed using fundamental concepts and numerical modeling, and we show that this is a multi-stage and multi-parametric problem that needs careful consideration. To illustrate the roadmap, the vacuum vessel for the vertex locator detector (CERN) is used. The results are discussed and, using them, the steps and stages of the design optimization are suggested. The suggested procedure can be applied to optimize the design of any beamline insertion device and will contribute to the development of next generation particle/accelerator detectors and monitors.

Chemopreventive targeted treatment of head and neck precancer by Wee1 inhibition.

HPV-negative head and neck squamous cell carcinomas (HNSCCs) develop in precancerous changes in the mucosal lining of the upper-aerodigestive tract. These precancerous cells contain cancer-associated genomic changes and cause primary tumors and local relapses. Therapeutic strategies to eradicate these precancerous cells are very limited. Using functional genomic screens, we identified the therapeutic vulnerabilities of premalignant mucosal cells, which are shared with fully malignant HNSCC cells. We screened 319 previously identified tumor-lethal siRNAs on a panel of cancer and precancerous cell lines as well as primary fibroblasts. In total we identified 147 tumor-essential genes including 34 druggable candidates. Of these 34, 13 were also essential in premalignant cells. We investigated the variable molecular basis of the vulnerabilities in tumor and premalignant cell lines and found indications of collateral lethality. Wee1-like kinase (WEE1) was amongst the most promising targets for both tumor and precancerous cells. All four precancerous cell lines were highly sensitive to Wee1 inhibition by Adavosertib (AZD1775), while primary keratinocytes tolerated this inhibitor. Wee1 inhibition caused induction of DNA damage during S-phase followed by mitotic failure in (pre)cancer cells. In conclusion, we uncovered Wee1 inhibition as a promising chemopreventive strategy for precancerous cells, with comparable responses as fully transformed HNSCC cells.

Modular operation of microfluidic chips for highly parallelized cell culture and liquid dosing via a fluidic circuit board.

Microfluidic systems enable automated and highly parallelized cell culture with low volumes and defined liquid dosing. To achieve this, systems typically integrate all functions into a single, monolithic device as a "one size fits all" solution. However, this approach limits the end users' (re)design flexibility and complicates the addition of new functions to the system. To address this challenge, we propose and demonstrate a modular and standardized plug-and-play fluidic circuit board (FCB) for operating microfluidic building blocks (MFBBs), whereby both the FCB and the MFBBs contain integrated valves. A single FCB can parallelize up to three MFBBs of the same design or operate MFBBs with entirely different architectures. The operation of the MFBBs through the FCB is fully automated and does not incur the cost of an extra external footprint. We use this modular platform to control three microfluidic large-scale integration (mLSI) MFBBs, each of which features 64 microchambers suitable for cell culturing with high spatiotemporal control. We show as a proof of principle that we can culture human umbilical vein endothelial cells (HUVECs) for multiple days in the chambers of this MFBB. Moreover, we also use the same FCB to control an MFBB for liquid dosing with a high dynamic range. Our results demonstrate that MFBBs with different designs can be controlled and combined on a single FCB. Our novel modular approach to operating an automated microfluidic system for parallelized cell culture will enable greater experimental flexibility and facilitate the cooperation of different chips from different labs.

Establishment and Genetic Landscape of Precancer Cell Model Systems from the Head and Neck Mucosal Lining.

Head and neck squamous cell carcinomas (HNSCC) develop in fields of genetically altered cells. These fields are often dysplastic and a subset can be recognized as (erythro)leukoplakia, but most are macroscopically invisible. There is a lack of adequate treatment options to eradicate these fields, whereas they underlie the development of primary tumors as well as part of the local relapses. Unfortunately, there are almost no representative cellular models available to identify suitable treatment options. To this end, clinical biopsy specimens (n = 98) were cultured from normal appearing mucosa of the surgical margins of patients with primary HNSCCs (n = 32) to generate precancer cell culture models. This collection was extended with six previously established precancer cell cultures. Genetic analysis was performed on cultures with an extended life span (≥20 population doublings), the previously established cultures, and some randomly selected cultures. In total, cancer-associated changes were detected in 18 out of 34 (53%) cultures analyzed, which appeared to be independent of life span. A variety of genetic changes were identified, including somatic mutations as well as chromosomal copy-number aberrations (CNA). Loss of CDKN2A/p16Ink4A and mutations in TP53/p53 were most prominent. Remarkably, in some of these precancer cell cultures only chromosomal CNAs were detected, and none of the frequently occurring driver mutations. IMPLICATIONS: The precancer cell cultures, characterized herein, form a representative collection of field models that can be exploited to identify and validate new therapeutic strategies to prevent primary HNSCCs and local relapses.

Substitution of care for chronic heart failure from the hospital to the general practice: patients' perspectives.

BACKGROUND: Shifting care from the secondary to the primary system may present an opportunity to ensure that the increasing number of patients with chronic heart failure (CHF) receive high-quality care while containing costs. However, shifting from secondary to primary care might seem radical to patients. A qualitative insight into patients' issues, preferences, expectations and needs may help arrange a smooth transition from secondary to primary care for CHF patients. The aim of this exploratory study is therefore to gain insights into the way CHF patients in secondary care perceive the possibility of substitution of CHF care from secondary to primary care. METHODS: In total, fifteen semi-structured interviews were conducted with CHF patients. Topics discussed during the interviews were the advantages and disadvantages, attitudes of patients, preferences regarding the substitution and trust in the GP and cardiologist. A thematic analysis was performed. RESULTS: The minority of the patients welcomed the idea of substitution. Against that, the majority of the patients had various concerns. This attitude was mainly influenced by two main themes, confidence and security and accessibility. Most patients had more confidence in secondary than in primary care because of the greater level of knowledge and more possibilities for examination in secondary care and because of good relationships and positive previous experiences in secondary care. Patients also indicated that the general practice is geographically more easily accessible than the hospital. CONCLUSION: Patients had various concerns regarding the substitution of care for chronic heart failure. Addressing these concerns by informing them appropriately may contribute to a smooth and patient-friendly substitution from secondary to primary care. The fears and needs of patients could also be taken into account by policymakers when optimising the way substitution is organised, or when substitution is introduced.

Meeting patient expectations: patient expectations and recovery after hip or knee surgery.

BACKGROUND: Although patient-centred care could help increase the value of healthcare, practice variations in hip and knee surgery suggest that physicians guide clinical decisions more than patients do. This raises the question whether treatment outcomes still meet patients' expectations. This study investigated whether treatment outcomes measured by patient-reported outcome measures fulfil patients' main expectations (i.e. decreased pain or improved functioning). METHODS: Patients who underwent hip or knee surgery in 20 Dutch hospitals in 2014 were invited to a survey consisting of the KOOS Physical Function Short Form or the HOOS Physical Function Short Form, the NRS pain and the EQ-5D. Patients were asked their main reason for surgery and whether the expectations regarding this reason were fulfilled. RESULTS: A total of 2776 patients completed the survey. The most common reason for surgery was improved functioning (43.7%). Patients who were unable to choose between pain relief and improved functioning and patients who aimed for pain relief experienced more problems before surgery. However, patients who were unable to choose improved more than patients who wanted to improve their functioning on the NRS pain during use and the EQ-5D. More patients who aimed for pain relief felt that their expectations were fulfilled compared to other patients. CONCLUSIONS: Although an expectation for an outcome was not related to a greater improvement on that outcome, patient expectations were an indication of patients' improvement due to surgery. Differences in expectation fulfilment may be due to unrealistic expectations. To achieve optimal value, tailoring treatment using patient preferences and managing patient expectations is vital.

IgG response against Staphylococcus aureus is associated with severe atopic dermatitis in children.

BACKGROUND: An altered immune response against Staphylococcus aureus might contribute to inflammation and barrier damage in atopic dermatitis (AD). OBJECTIVES: To profile IgG antibodies against 55 S. aureus antigens in sera of children with mild-to-severe AD and to evaluate the association between IgG levels and disease severity. METHODS: In this cross-sectional study, we included children with AD from two interventional study cohorts, the Shared Medical Appointment (SMA) cohort (n = 131) and the older DAVOS cohort (n = 76). AD severity was assessed using the Self-Administered Eczema Area and Severity Index (SA-EASI) and levels of thymus and activation-regulated chemokine (TARC) in serum. IgG antibody levels against 55 S. aureus antigens were quantified simultaneously using a Luminex assay. Pair-wise correlations were calculated between the 55 IgG levels using the Spearman rank correlation test. Linear regression analysis was performed to test for associations between 55 IgG levels and SA-EASI and TARC, adjusting for age, sex and S. aureus colonization. RESULTS: In the SMA cohort, 16 antigens were associated with SA-EASI and 12 with TARC (10 overlapping antigens; P-values 0·001-0·044). The associated IgG antibodies targeted mainly secreted proteins with immunomodulatory functions. In the DAVOS study, IgG levels against only four and one S. aureus antigen(s) were associated with SA-EASI and TARC, respectively (no overlap). CONCLUSIONS: In young children, severity of AD is associated with an IgG response directed against S. aureus antigens with mainly immunomodulatory functions. These findings encourage further evaluation of the role of S. aureus in the pathogenesis of AD.

Targeting PLK1 as a novel chemopreventive approach to eradicate preneoplastic mucosal changes in the head and neck.

Head and neck squamous cell carcinomas (HNSCC) and local relapses thereof develop in preneoplastic fields in the mucosal linings of the upper aerodigestive tract. These fields are characterized by tumor-associated genetic changes, are frequently dysplastic and occasionally macroscopically visible. Currently, no adequate treatment options exist to prevent tumor development. Array-based screening with a panel of tumor-lethal small interfering RNAs (siRNAs) identified Polo-like kinase 1 (PLK1) as essential for survival of preneoplastic cells. Inhibition of PLK1 caused cell death of preneoplastic and HNSCC cells, while primary cells were hardly affected. Both siRNAs and small molecule inhibitors caused a strong G2/M cell cycle arrest accompanied by formation of monopolar spindles. In a xenografted mouse model PLK1 caused a significant tumor growth delay and cures, while chemoradiation had no effect. Thus, PLK1 seems to be a promising target for chemopreventive treatment of preneoplastic cells, and could be applied to prevent HNSCC and local relapses.

Stabilizing prevalence trends of eczema, asthma and rhinoconjunctivitis in Dutch schoolchildren (2001-2010).

In contrast to many countries, a decrease in childhood wheeze prevalence was previously reported for the Netherlands. In repeated cross-sectional surveys in 2001, 2005 and 2010, we investigated whether this trend continued, and additionally examined prevalence trends of eczema, asthma and rhinoconjunctivitis among 8- to 11-year-old schoolchildren eligible for a routine physical examination. Overall, ~90% participated (mean age: 8.8 years in 2001 and 10.5 years in 2005 and 2010). Eczema, wheeze and asthma prevalence did not change significantly between 2001 and 2010, but rhinoconjunctivitis prevalence increased from 8.4% in 2001 to 12.3% in both 2005 and 2010 (Ptrend < 0.01). In conclusion, after a decrease in wheeze prevalence among Dutch schoolchildren between 1989 and 2001, no further decrease was observed until 2010. Similarly, the prevalence of eczema and asthma remained stable, but rhinoconjunctivitis prevalence increased between 2001 and 2010. The latter may be an effect of older age and not a true increase over time.

Effect of different head and neck positions on behaviour, heart rate variability and cortisol levels in lunged Royal Dutch Sport horses.

Different head-and-neck positions (HNPs) are discussed in relation to potential welfare issues. To evaluate the effect on welfare, seven Royal Dutch Sport horses were studied in five predetermined HNPs: (1) unrestrained (HNP1); (2) neck raised, bridge of nose around the vertical (HNP2); (3) neck lowered and considerably flexed, bridge of nose pointing towards the chest (HNP4); (4) neck raised and extended, bridge of nose in front of the vertical (HNP5), and (5) neck lowered and flexed, bridge of nose pointing towards the carpus (HNP7). A standardised exercise test (SET) of 34 min consisted of trot, canter and walk. Behaviour was recorded with a pre-defined ethogram and R-R intervals measured using telemetry. Cortisol concentrations were taken at the start, 5 and 30 min after the SET. Behaviour around the SET was scored separately. Conflict behaviours increased significantly during HNP2 when compared with HNP1, HNP4 and HNP7 during the SET, and there was significant negative anticipation before HNP2 and HNP7. The heart rate variability (HRV) frequency domain for HNP2 showed a significantly increased low frequency peak (LFpeak) compared with other HNPs, and there was a decrease in very low frequency (VLF%) compared with HNP1. HNP4 showed a significant increase in LF% and decrease in VLF% compared with HNP1. Saliva cortisol concentrations were significantly increased in HNP2 at 5 and 30 min after exercise. Increased conflict behaviour was mostly observed in HNP2, but there was a raised HRV suggesting a sympathetic shift in HNP2 and HNP4, and increased cortisol concentrations during HNP2 indicated a stress response.

Monocrystalline silicon photovoltaic luminescent solar concentrator with 4.2% power conversion efficiency.

We report conversion efficiencies of experimental single and dual light guide luminescent solar concentrators. We have built several 5 cm × 5 cm and 10× cm × 10 cm luminescent solar concentrator (LSC) demonstrators consisting of c-Si photovoltaic cells attached to luminescent light guides of Lumogen F Red 305 dye and perylene perinone dye. The highest overall efficiency obtained was 4.2% on a 5 cm × 5 cm stacked dual light guide using both luminescent materials. To our knowledge, this is the highest reported experimentally determined efficiency for c-Si photovoltaic-based LSCs. Furthermore, we also produced a 5 cm × 5 cm LSC specimen based on an inorganic phosphor layer with an overall efficiency of 2.5%.

Aberrant intestinal stem cell lineage dynamics in Peutz-Jeghers syndrome and familial adenomatous polyposis consistent with protracted clonal evolution in the crypt.

OBJECTIVE: Genetic predisposition to cancer in Peutz-Jeghers syndrome (PJS) and the role of germline serine-threonine kinase (LKB1) mutations are poorly understood. The authors studied the effect of germline LKB1 mutations on intestinal stem cell dynamics in unaffected flat PJS mucosa. Recent research has documented that the intestinal crypt houses multiple equipotent stem cell lineages. Lineages continuously compete through random drifts, while somatically inherited methylation patterns record clonal diversity. DESIGN: To study the effect of germline LKB1 mutations on clonal expansion, the authors performed quantitative analyses of cardiac-specific homeobox methylation pattern diversity in crypts isolated from unaffected colonic mucosa obtained from archival PJS patient material. The authors compared methylation density and methylation pattern diversity in patients with PJS to those in patients with familial adenomatous polyposis and age-matched controls. RESULTS: The percentage of total methylation is comparable between groups, but the number of unique methylation patterns is significantly increased for patients with familial adenomatous polyposis and patients with PJS compared to control subjects. CONCLUSIONS: Monoallelic LKB1 loss is not silent and provokes a protracted clonal evolution in the crypt. The increased methylation pattern diversity observed in unaffected PJS mucosa predicts that premalignant lesions will arise at an accelerated pace compared to the general population.

Applicability of geometrical optics to in-plane liquid-crystal configurations.

We study the applicability of geometrical optics to inhomogeneous dielectric nongyrotropic optically anisotropic media typically found in in-plane liquid-crystal configurations with refractive indices n(o)=1.5 and n(e)=1.7. To this end, we compare the results of advanced ray- and wave-optics simulations of the propagation of an incident plane wave to a special anisotropic configuration. Based on the results, we conclude that for a good agreement between ray and wave optics, a maximum change in optical properties should occur over a distance of at least 20 wavelengths.

Simulations of a liquid-crystal-based electro-optical switch.

We present simulations of a novel liquid-crystal-based electro-optical device that enables a switching effect owing to a backreflection phenomenon. In the simulations, we exploit the optical properties of a liquid-crystal layer with a Freédericksz alignment in an unconventional way. The resulting switching effect of the proposed optical design can be controlled by means of an external electric field. Possible applications of the liquid-crystal device can be found in, but are not restricted to, optical communication systems and lighting applications.