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In Europe alone, each year 5500 people require a life‐saving liver transplantation, but 18% die before receiving one due to the shortage of donor organs. Whole organ engineering, utilizing decellularized liver scaffolds repopulated with autologous cells, is an attractive alternative to increase the pool of available organs for transplantation. The development of this technology is hampered by a lack of a suitable large‐animal model representative of the human physiology and a reliable and continuous cell source. We have generated porcine intrahepatic cholangiocyte organoids from adult stem cells and demonstrate that these cultures remained stable over multiple passages whilst retaining the ability to differentiate into hepatocyte‐ and cholangiocyte‐like cells. Recellularization onto porcine scaffolds was efficient and the organoids homogeneously differentiated, even showing polarization. Our porcine intrahepatic cholangiocyte system, combined with porcine liver scaffold paves the way for developing whole liver engineering in a relevant large‐animal model. [ABSTRACT FROM AUTHOR]

Dysregulation of tryptophan metabolism has been linked to colorectal tumorigenesis; however, epidemiological studies investigating tryptophan metabolites in relation to colorectal cancer risk are limited. We studied associations of plasma tryptophan, serotonin and kynurenine with colon cancer risk in two studies with cancer patients and controls, and in one prospective cohort: ColoCare Study (110 patients/153 controls), the Colorectal Cancer Study of Austria (CORSA; 46 patients/390 controls) and the European Prospective Investigation into Cancer and Nutrition (EPIC; 456 matched case‐control pairs). Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for colon cancer risk. Tryptophan was inversely associated with colon cancer risk in ColoCare (OR per 1‐SD = 0.44; 95% CI, 0.31‐0.64) and EPIC (OR per 1‐SD = 0.86; 95% CI, 0.74‐0.99). Comparing detectable vs nondetectable levels, serotonin was positively associated with colon cancer in CORSA (OR = 6.39; 95% CI, 3.61‐11.3) and EPIC (OR = 2.03; 95% CI, 1.20‐3.40). Kynurenine was inversely associated with colon cancer in ColoCare (OR per 1‐SD = 0.74; 95% CI, 0.55‐0.98), positively associated in CORSA (OR per 1‐SD = 1.79; 95% CI, 1.27‐2.52), while no association was observed in EPIC. The kynurenine‐to‐tryptophan ratio was positively associated with colon cancer in ColoCare (OR per 1‐SD = 1.38; 95% CI, 1.03‐1.84) and CORSA (OR per 1‐SD = 1.44; 95% CI, 1.06‐1.96), but not in EPIC. These results suggest that higher plasma tryptophan may be associated with lower colon cancer risk, while increased serotonin may be associated with a higher risk of colon cancer. The kynurenine‐to‐tryptophan ratio may also reflect altered tryptophan catabolism during colon cancer development. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the second most common cause of cancer‐related death globally, with marked differences in prognosis by disease stage at diagnosis. We studied circulating metabolites in relation to disease stage to improve the understanding of metabolic pathways related to colorectal cancer progression. We investigated plasma concentrations of 130 metabolites among 744 Stages I–IV colorectal cancer patients from ongoing cohort studies. Plasma samples, collected at diagnosis, were analyzed with liquid chromatography‐mass spectrometry using the Biocrates AbsoluteIDQ™ p180 kit. We assessed associations between metabolite concentrations and stage using multinomial and multivariable logistic regression models. Analyses were adjusted for potential confounders as well as multiple testing using false discovery rate (FDR) correction. Patients presented with 23, 28, 39 and 10% of Stages I–IV disease, respectively. Concentrations of sphingomyelin C26:0 were lower in Stage III patients compared to Stage I patients (pFDR < 0.05). Concentrations of sphingomyelin C18:0 and phosphatidylcholine (diacyl) C32:0 were statistically significantly higher, while citrulline, histidine, phosphatidylcholine (diacyl) C34:4, phosphatidylcholine (acyl‐alkyl) C40:1 and lysophosphatidylcholines (acyl) C16:0 and C17:0 concentrations were lower in Stage IV compared to Stage I patients (pFDR < 0.05). Our results suggest that metabolic pathways involving among others citrulline and histidine, implicated previously in colorectal cancer development, may also be linked to colorectal cancer progression. What's new? Metabolomics is a sophisticated method for investigating whether the metabolite profile of a patient's blood, etc., may reflect the pathophysiological state of cancers and other diseases. In the present study, the authors analyzed circulating metabolites, seeking biomarkers related to colorectal cancer progression. Their results at various stages of colorectal cancer suggest that metabolic pathways involving citrulline, histidine, and other molecules that have been previously implicated in colorectal cancer development may also be linked to progression. [ABSTRACT FROM AUTHOR]

Colorectal cancer is known to arise from multiple tumorigenic pathways; however, the underlying mechanisms remain not completely understood. Metabolomics is becoming an increasingly popular tool in assessing biological processes. Previous metabolomics research focusing on colorectal cancer is limited by sample size and did not replicate findings in independent study populations to verify robustness of reported findings. Here, we performed a ultrahigh performance liquid chromatography‐quadrupole time‐of‐flight mass spectrometry (UHPLC‐QTOF‐MS) screening on EDTA plasma from 268 colorectal cancer patients and 353 controls using independent discovery and replication sets from two European cohorts (ColoCare Study: n = 180 patients/n = 153 controls; the Colorectal Cancer Study of Austria (CORSA) n = 88 patients/n = 200 controls), aiming to identify circulating plasma metabolites associated with colorectal cancer and to improve knowledge regarding colorectal cancer etiology. Multiple logistic regression models were used to test the association between disease state and metabolic features. Statistically significant associated features in the discovery set were taken forward and tested in the replication set to assure robustness of our findings. All models were adjusted for sex, age, BMI and smoking status and corrected for multiple testing using False Discovery Rate. Demographic and clinical data were abstracted from questionnaires and medical records. What's new? Colorectal cancer exhibits certain characteristic changes in metabolic pathways. To expand upon previous findings, these authors performed a discovery‐replication study using two large independent study populations from different countries, Germany and Austria. They tested metabolic profiles of cancer patients and controls, identifying 691 statistically significant features in the discovery cohort. Testing the second cohort narrowed it to 97. These corresponded to 28 metabolites, of which 15 could be identified. It will be useful to go forward with prospective analysis on these 15 metabolites, to determine whether they have predictive or prognostic value. [ABSTRACT FROM AUTHOR]

Direct reprogramming represents an easy technique to generate induced hepatocytes (iHeps) from somatic cells. However, current protocols are accompanied by several drawbacks as iHeps are heterogenous and lack fully mature phenotypes of primary hepatocytes. Here, we established a polycistronic expression system to induce the direct reprogramming of mouse embryonic fibroblasts towards hepatocytes. The resulting iHeps are homogenous and display key properties of primary hepatocytes, such as expression of hepatocyte markers, albumin secretion, and presence of liver transaminases. iHeps also possess the capacity to repopulate decellularized liver tissue and exhibit enhanced hepatic maturation. As such, we present a novel strategy to generate homogenous and functional iHeps for applications in tissue engineering and cell therapy. Direct reprogramming represents an easy technique to generate hepatocyte‐like cells from somatic cells. However, current protocols are accompanied by several drawbacks as induced hepatocytes (iHeps) are heterogenous and lack fully mature phenotypes of primary hepatocytes. Here, we established a polycistronic expression system to induce the direct reprogramming of mouse embryonic fibroblasts towards hepatocytes. [ABSTRACT FROM AUTHOR]

Abstract: The screener for mild intellectual disability (SCIL) was developed to screen for mild intellectual disability (IQ below 85). The aims of this study were (a) to examine the predictive validity of the SCIL in screening for intellectual disability among police suspects and (b) to explore the prevalence of cognitive intellectual disability among suspects in police custody in the Netherlands. An unselected sample of police suspects (N = 178) charged with a variety of offences was assessed with the SCIL, a Wechsler Adult Intelligence Scale (WAIS)‐III‐NL short form, and a malingering measure. The SCIL screened 50.0% of the sample as having mild intellectual disabilities, whereas the short WAIS classified 84.3% of the sample with an IQ below 85. A principal component analysis of the SCIL showed ambiguous results. Furthermore, the short WAIS classified 55.6% of our sample with a borderline IQ (IQ = 70–84), 84.3% with an IQ below 85 and 28.7% with an IQ below 70. The prevalence of intellectual disability in this sample of Dutch (police) suspects appears to be higher than prevalence rates found in previous international studies. More exhaustive research is needed to examine the prevalence of intellectual disabilities in police suspects, and the utility of the SCIL to screen for these disabilities. [ABSTRACT FROM AUTHOR]

Abstract: The circadian clock is an evolutionarily conserved timekeeper that adapts body physiology to diurnal cycles of around 24 h by influencing a wide variety of processes such as sleep‐to‐wake transitions, feeding and fasting patterns, body temperature, and hormone regulation. The molecular clock machinery comprises a pathway that is driven by rhythmic docking of the transcription factors BMAL1 and CLOCK on clock‐controlled output genes, which results in tissue‐specific oscillatory gene expression programs. Genetic as well as environmental perturbation of the circadian clock has been implicated in various diseases ranging from sleep to metabolic disorders and cancer development. Here, we review the origination of circadian rhythms in stem cells and their function in differentiated cells and organs. We describe how clocks influence stem cell maintenance and organ physiology, as well as how rhythmicity affects lineage commitment, tissue regeneration, and aging. [ABSTRACT FROM AUTHOR]

Cell-autonomous circadian oscillations strongly influence tissue physiology and pathophysiology of peripheral organs including the heart, in which the circadian clock is known to determine cardiac metabolism and the outcome of for instance ischemic stress. Human pluripotent stem cells represent a powerful tool to study developmental processes in vitro, but the extent to which human embryonic stem ( ES) cell-derived cardiomyocytes establish circadian rhythmicity in the absence of a systemic context is unknown. Here we demonstrate that while undifferentiated human ES cells do not possess an intrinsic functional clock, oscillatory expression of known core clock genes emerges spontaneously during directed cardiac differentiation. We identify a set of clock-controlled output genes that contain an oscillatory network of stress-related transcripts. Furthermore, we demonstrate that this network results in a time-dependent functional response to doxorubicin, a frequently used anti-cancer drug with known cardiotoxic side effects. Taken together, our data provide a framework from which the effect of oscillatory gene expression on cardiomyocyte physiology can be modeled in vitro, and demonstrate the influence of a functional clock on experimental outcome. [ABSTRACT FROM AUTHOR]

The authors discuss the first empirical investigation into the Scenario Model, an interview method by the Dutch police to interview alleged child victims of abuse. Highlight include the similarity between the Scenario Model and the National Institute of Child Health and Human Development, the central importance of open prompts in the writings about the Scenario Model, and elimination or reduction of the free-call portion of investigative interviews for children with autism spectrum disorder.

Purpose: Hyperthermia is an established (neo)adjuvant treatment modality for a number of pelvic malignancies. Optimal treatment of these tumors requires robust treatment planning, but up until now, the urinary bladder was not modeled accurately, making current simulations less reliable. The authors improved the dielectric and thermophysical model of the urinary bladder in their treatment planning system, and showed the improvements using phantom experiments. Methods: The authors suspended a porcine bladder in muscle tissue equivalent gel and filled it with 120 ml 0.9% saline. The authors heated the phantom during 15 min with their deep hyperthermia device, using clinical settings, and measured the temperature both inside and outside the bladder. The authors simulated the experiment, both using the clinically used treatment planning system, and using the improved model featuring correct dielectric properties for the bladder content and an enhanced thermophysical model, enabling the simulation of convection. Results: Although the dielectric changes have an impact throughout the phantom, the dominant effect is a higher net heat absorption in the bladder. The effects of changing the thermophysical model are limited to the bladder and its surroundings, but result in a very different temperature profile. The temperatures predicted by the simulations using the new bladder model were in much better agreement with the measurements than those predicted by currently used treatment planning system. Conclusions: Modeling convection in the urinary bladder is very important for accurate hyperthermia treatment planning in the pelvic area. [ABSTRACT FROM AUTHOR]

Introduction: Definitive chemoradiotherapy (dCRT) is standard care for localised inoperable/unresectable oesophageal tumours. Many surgical series have reported on distribution of lymph node metastases (LNM) in resected patients. However, no data is available on the distribution of at-risk LN regions in this more unfavourable patient group. This study aimed to determine the spread of LNM using FDG-PET/CT, to compare it with the distribution in surgical series and to define its impact on the definition of elective LN irradiation (ENI).Methods: FDG-PET/CT images of patients with oesophageal cancer treated with dCRT (from 2003 to 2013) were reviewed to identify the anatomic distribution of FDG-avid LNs. Tumours were divided according to proximal, mid-thoracic or distal localisation.Results: About 105 consecutive patients entered analysis. The highest numbers of FDG-avid LNs in proximal tumours were at LN station 101R (45%) and 106recL (35%). For mid-thoracic tumours at 104R (30%) and 105 (30%). For tumours located in the distal oesophagus, the most common sites were along the lesser curvature of the stomach (21%) and the left gastric artery (21%). Except for the supraclavicular and pretracheal nodes, there were no positive locoregional LNM found outside the standard surgical resection area.Conclusion: Our results show a good correlation between the distribution of nodal volumes at risk in surgical series and on FDG-PET/CT. The results can be used to determine target definition in dCRT for oesophageal cancer. For mid-thoracic tumours, the current target delineation guidelines may be extended based on the risk of node involvement, but more clinical studies are needed to determine if the potential harm of expanding the CTV outweighs the potential benefit. [ABSTRACT FROM AUTHOR]

Embryonic stem cell ( ESC) cultures display a heterogeneous gene expression profile, ranging from a pristine naïve pluripotent state to a primed epiblast state. Addition of inhibitors of GSK3β and MEK (so-called 2i conditions) pushes ESC cultures toward a more homogeneous naïve pluripotent state, but the molecular underpinnings of this naïve transition are not completely understood. Here, we demonstrate that DAZL, an RNA-binding protein known to play a key role in germ-cell development, marks a subpopulation of ESCs that is actively transitioning toward naïve pluripotency. Moreover, DAZL plays an essential role in the active reprogramming of cytosine methylation. We demonstrate that DAZL associates with mRNA of Tet1, a catalyst of 5-hydroxylation of methyl-cytosine, and enhances Tet1 mRNA translation. Overexpression of DAZL in heterogeneous ESC cultures results in elevated TET1 protein levels as well as increased global hydroxymethylation. Conversely, null mutation of Dazl severely stunts 2i-mediated TET1 induction and hydroxymethylation. Our results provide insight into the regulation of the acquisition of naïve pluripotency and demonstrate that DAZL enhances TET1-mediated cytosine hydroxymethylation in ESCs that are actively reprogramming to a pluripotent ground state. [ABSTRACT FROM AUTHOR]

This study describes for the first time the cultivation of Cerastoderma edule on a commercial scale. A protocol to grow F2 generation cockles was developed, which led to fine-tuning experiments for broodstock conditioning and spat growth. Broodstock animals were conditioned with diets of Isochrysis galbana (T-Iso) or Tetraselmis suecica, whereas a third group was not fed. The best diet, T. suecica, induced 12 females out of 100 animals to spawn a total of 3 380 000 eggs. The non-fed group did not spawn. Cockle spat (4.9 ± 1.0 mm) grew best when given a mixed diet of C. muelleri, T-Iso and Sceletonema costatum, or a mixture of P. tricornutum and S. costatum at a concentration of 240 cells μl−1 day−1 , resulting in a tripling of their wet weight after 14 days. The impact of density, burrowing substrate and food availability on cockle spat growth (41 days old, 5.6 ± 1.2 mm) was studied for 11 weeks. Best results were obtained by culturing spat at ad libitum food conditions at 500 ind m−2, resulting in an average growth rate of 168 μm day−1, an average final size of 19.0 ± 1.9 mm and a total final biomass of 1040 g m−2. [ABSTRACT FROM AUTHOR]

Advances in stem cell biology have raised legal challenges to the patentability of stem cells and any derived technologies and processes. In 1999, Oliver Brüstle was granted a patent for the generation and therapeutic use of neural cells derived from human embryonic stem cells (hESCs). The patent was challenged and put before the European Court of Justice, which ruled that inventions involving the prior destruction of human embryos cannot be patented. The legal maneuvering around this case demonstrates that the future of stem cell-based patents in Europe remains unsettled. Furthermore, owing to the European Court's broad definition of hESC as 'any cell that is capable of commencing development into a human being,' novel technologies that could eliminate the need for hESCs, such as induced pluripotent stem cells (iPSCs), are at risk of being included under the same ruling. Advances in the in vitro development of germ cells from pluripotent stem cells may one day provide a direct developmental path from iPSC to oocyte and sperm, and, according to the European Court's reasoning, legally equate iPSCs with human embryos. In this review, we will briefly discuss the Brüstle v Greenpeace case and the implications of the European Court of Justice's ruling. We will identify potential risks for stem cell research and future therapeutics resulting from the broad legal definition of the human embryo. Finally, we will broach the current legal landscape, as this broad definition has also created great uncertainty about the status of human iPSCs. [ABSTRACT FROM AUTHOR]

Objectives: This paper describes the further development and psychometric properties of an instrument to measure cancer patients' reasons to want complete or limited information: the Considerations Concerning Cancer Information questionnaire (CCCI). Understanding cancer patients' reasons to want complete or limited information will provide the physician with information that enables him or her to tailor information giving. Methods: CCCI's content validity, internal structure, and convergent validity were investigated among 145 cancer patients, new to radiotherapy. Results: Underlying reasons for information preference among cancer patients were derived from existing qualitative studies, narratives, and interviews. This resulted in the CCCI containing two parts: reasons to favor complete information disclosure and reasons to prefer only limited information about disease and treatment. The four identified dimensions to prefer information consist of: sense of control, expectations of others, anxiety, and autonomy. The four dimensions for reasons to give up on acquiring information consist of: avoidance, optimism, comprehension, and not wanting to be a burden. Confirmatory factor analysis indicated that the measurement model provided good fit to the data. Scales had good internal consistency, satisfactory item-total correlations corrected for overlap and satisfactory convergent validity. Conclusions: These findings confirm evidence of the reliability and validity of the CCCI for use in cancer care. Researchers and health-care providers can use the instrument to assess cancer patients' reasons to want complete or limited information and provide tailored care. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Primordial germ cells comprise a privileged cellular class with in the embryo charged with the elite task of maintaining species longevity. While in lower organisms germ-cell fate is determined by the allocation of germ plasm, mammalian germ-line differentiation requires extracellular signals that converge upon the proximal epiblast. Studies using mutant mice or explanted embryos have identified some of the factors controlling primordial germ-cell specification, such as members of the BMP family, but considerable gaps still exist in our understanding of the complete signaling network. Comprehensive investigations of mammalian germline specification have been hampered by the inaccessibility of this cell population in the early embryo. Recently, however, several labs including our own have derived primordial germ cells from embryonic stem cells in vitro, thus providing a powerful new technique for the study of germ cells. In this review the different methods used for the in vitro generation of germ cells and how these techniques may be improved and applied to further advance our knowledge of germ-cell biology are discussed. [ABSTRACT FROM AUTHOR]