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The contribution of genetic predisposing factors to the development of pediatric acute lymphoblastic leukemia (ALL), the most frequently diagnosed cancer in childhood, has not been fully elucidated. Children presenting with multiple de novoleukemias are more likely to suffer from genetic predisposition. Here, we selected five of these patients and analyzed the mutational spectrum of normal and malignant tissues. In two patients, we identified germline mutations in TYK2, a member of the JAK tyrosine kinase family. These mutations were located in two adjacent codons of the pseudokinase domain (p.Pro760Leu and p.Gly761Val). In silicomodeling revealed that both mutations affect the conformation of this autoregulatory domain. Consistent with this notion, both germline mutations promote TYK2 autophosphorylation and activate downstream STAT family members, which could be blocked with the JAK kinase inhibitor I. These data indicate that germline activating TYK2 mutations predispose to the development of ALL.

E2F transcription factors are important regulators of the cell cycle, and unrestrained activation of E2F-dependent transcription is considered to be an important driver of tumor formation and progression. Although highly expressed in normal skin and skin cancer, the role of the atypical E2Fs, E2F7 and E2F8, in keratinocyte homeostasis, regeneration and tumorigenesis is unknown. Surprisingly, keratinocyte-specific deletion of E2F7 and E2F8 in mice did not interfere with skin development and wound healing. However, the rate for successful isolation and establishment of E2f7/8-deficient primary keratinocyte cultures was much higher than for wild-type keratinocytes. Moreover, E2f7/8-deficient primary keratinocytes proliferate more efficiently under stress conditions, such as low/high confluence or DNA damage. Application of in vivo stress using the DMBA/TPA skin carcinogenesis protocol revealed that combined inactivation of E2f7/8 enhanced tumorigenesis and accelerated malignant progression. Loss of atypical E2Fs resulted in increased expression of E2F target genes, including E2f1. Additional loss of E2f1 did not rescue, but worsened skin tumorigenesis. We show that loss of E2F7/8 triggers apoptosis via induction of E2F1 in response to stress, indicating that the tumor-promoting effect of E2F7/8 inactivation can be partially compensated via E2F1-dependent apoptosis. Importantly, E2F7/8 repressed a large set of E2F target genes that are highly expressed in human patients with skin cancer. Together, our studies demonstrate that atypical E2Fs act as tumor suppressors, most likely via transcriptional repression of cell cycle genes in response to stress.

Mice deficient in the DNA excision-repair gene Ercc1 (Ercc1∆/−) show numerous accelerated ageing features that limit their lifespan to 4-6 months. They also exhibit a ‘survival response’, which suppresses growth and enhances cellular maintenance. Such a response resembles the anti-ageing response induced by dietary restriction (also known as caloric restriction). Here we report that a dietary restriction of 30% tripled the median and maximal remaining lifespans of these progeroid mice, strongly retarding numerous aspects of accelerated ageing. Mice undergoing dietary restriction retained 50% more neurons and maintained full motor function far beyond the lifespan of mice fed ad libitum. Other DNA-repair-deficient, progeroid Xpg−/−(also known as Ercc5−/−) mice, a model of Cockayne syndrome, responded similarly. The dietary restriction response in Ercc1∆/−mice closely resembled the effects of dietary restriction in wild-type animals. Notably, liver tissue from Ercc1∆/−mice fed ad libitum showed preferential extinction of the expression of long genes, a phenomenon we also observed in several tissues ageing normally. This is consistent with the accumulation of stochastic, transcription-blocking lesions that affect long genes more than short ones. Dietary restriction largely prevented this declining transcriptional output and reduced the number of γH2AX DNA damage foci, indicating that dietary restriction preserves genome function by alleviating DNA damage. Our findings establish the Ercc1∆/−mouse as a powerful model organism for health-sustaining interventions, reveal potential for reducing endogenous DNA damage, facilitate a better understanding of the molecular mechanism of dietary restriction and suggest a role for counterintuitive dietary-restriction-like therapy for human progeroid genome instability syndromes and possibly neurodegeneration in general.

Deletions in IKZF1are found in ~15% of children with B-cell precursor acute lymphoblastic leukemia (BCP-ALL). There is strong evidence for the poor prognosis of IKZF1deletions affecting exons 4–7 and exons 1–8, but evidence for the remaining 33% of cases harboring other variants of IKZF1deletions is lacking. In an international multicenter study we analyzed the prognostic value of these rare variants in a case–control design. Each IKZF1-deleted case was matched to three IKZF1wild-type controls based on cytogenetic subtype, treatment protocol, risk stratification arm, white blood cell count and age. Hazard ratios for the prognostic impact of rare IKZF1deletions on event-free survival were calculated by matched pair Cox regression. Matched pair analysis for all 134 cases with rare IKZF1deletions together revealed a poor prognosis (P<0.001) that was evident in each risk stratification arm. Rare variant types with the most unfavorable event-free survival were DEL 2–7 (P=0.03), DEL 2–8 (P=0.002) and DEL-Other (P<0.001). The prognosis of each type of rare variant was equal or worse compared with the well-known major DEL 4–7 and DEL 1–8 IKZF1deletion variants. We therefore conclude that all variants of rare IKZF1deletions are associated with an unfavorable prognosis in pediatric BCP-ALL.

To assess whether regulatory T cells are present in rejecting human cardiac allografts, we performed functional analyses of graft lymphocytes (GLs) expanded from endomyocardial biopsies (EMB; n 5) with histological signs of acute cellular rejection. The GL cultures were tested for their proliferative capacity and regulatory activity on allogeneic-stimulated peripheral blood mononuclear cells (PBMC) of the patient (ratio PBMC:GLs 5:1). Three of these GL cultures were hyporesponsive to donor antigens and suppressed the antidonor proliferative T-cell response of PBMC, but not the anti-third-party response. Interestingly, it was the CD8GL subset of these cultures that inhibited the antidonor response (65-91 inhibition of the proportion of proliferating cells); the CD4GLs of the expanded GL cultures were not suppressive. In conclusion, CD8GLs expanded from rejecting human cardiac allografts can exhibit donor-specific immune regulatory activities in vitro. We suggest that during acute cellular rejection, GLs may not only consist of graft-destructing effector T cells, but also of cells of the CD8type with the potential to specifically inhibit antidonor immune reactivity.

To assess whether regulatory T cells are present in rejecting human cardiac allografts, we performed functional analyses of graft lymphocytes (GLs) expanded from endomyocardial biopsies (EMB; n = 5) with histological signs of acute cellular rejection. The GL cultures were tested for their proliferative capacity and regulatory activity on allogeneic-stimulated peripheral blood mononuclear cells (PBMC) of the patient (ratio PBMC:GLs = 5:1). Three of these GL cultures were hyporesponsive to donor antigens and suppressed the antidonor proliferative T-cell response of PBMC, but not the anti-third-party response. Interestingly, it was the CD8+GL subset of these cultures that inhibited the antidonor response (65–91% inhibition of the proportion of proliferating cells); the CD4+GLs of the expanded GL cultures were not suppressive. In conclusion, CD8+GLs expanded from rejecting human cardiac allografts can exhibit donor-specific immune regulatory activities in vitro. We suggest that during acute cellular rejection, GLs may not only consist of graft-destructing effector T cells, but also of cells of the CD8+type with the potential to specifically inhibit antidonor immune reactivity.

We investigate the energy dependence of stopping and hadron production in high‐energy heavy‐ion collisions based on a three‐sources Relativistic Diffusion Model. The transport coefficients are extrapolated from Au + Au and Cu + Cu at RHIC energies ($\sqrt{s_{NN}}$= 19.6–200 GeV) to Pb + Pb at LHC energies $\sqrt{s_{NN}}$= 5.52 TeV. Rapidity distributions for net protons, and pseudorapidity spectra for produced charged particles in central collisions are compared to data at RHIC energies, and discussed for several extrapolations to LHC energies.

We investigate the energy dependence of stopping and hadron production in high-energy heavy-ion collisions based on a three-sources Relativistic Diffusion Model. The transport coefficients are extrapolated from Au + Au and Cu + Cu at RHIC energies ($\sqrt{s_{NN}}$ = 19.6–200 GeV) to Pb + Pb at LHC energies $\sqrt{s_{NN}}$ = 5.52 TeV. Rapidity distributions for net protons, and pseudorapidity spectra for produced charged particles in central collisions are compared to data at RHIC energies, and discussed for several extrapolations to LHC energies.

Abstract.: The paper motivates and describes a model oriented approach for consistent specification of interface suites in UML. An interface suite is a coherent collection of interfaces defining interactions that transcend component boundaries. The specification of interface suites contains diagrammatic views and documentation, but it is extended with templates for structured specifications deriving from the ISpec approach. To guarantee that the specification views, documentation and templates are consistent, a specification model has been constructed. The model contains both structural and behavioural information, represented in the form of sequences of carefully designed tuples. The model provides the underlying structure for the tool supporting the design process. The tool directs the designer to specify all elements of the model in a consistent way. The specification is collected both by customized specification templates and by diagrams. The documentation and the diagram elements – both derived from the template information – are automatically generated. This prevents errors and provides specification consistency.

The p24 family consists of type I transmembrane proteins that are present abundantly in transport vesicles, may play a role in endoplasmic reticulum-to-Golgi cargo transport, and have been classified into subfamilies named p24alpha, -beta, -gamma, and -delta. We previously identified a member of the p24delta subfamily that is coordinately expressed with the prohormone proopiomelanocortin (POMC) in the melanotrope cells of the intermediate pituitary during black background adaptation of the amphibian Xenopus laevis ( approximately 30-fold increase in POMC mRNA). In this study, we report on the characterization of this p24delta member (Xp24delta(2)) and on the identification and characterization of a second member (Xp24delta(1)) that is also expressed in the melanotrope cells and that has 66% amino acid sequence identity to Xp24delta(2). The two p24delta members are ubiquitously expressed, but Xp24delta(2) is neuroendocrine enriched. During black background adaptation, the amount of the Xp24delta(2) protein in the intermediate pituitary was increased approximately 25 times, whereas Xp24delta(1) protein expression was increased only 2.5 times. Furthermore, the level of Xp24delta(2) mRNA was approximately 5-fold higher in the melanotrope cells of black-adapted animals than in those of white-adapted animals, whereas Xp24delta(1) mRNA expression was not induced. Therefore, the expression of Xp24delta(2) specifically correlates with the expression of POMC. Together, our findings suggest that p24delta proteins have a role in selective protein transport in the secretory pathway.

Responses to drug information questions posted on the Internet Usenet pharmacy newsgroup sci.med. pharmacy were compared for accuracy with responses from drug information centers (DICs). Twenty-five questions were randomly selected from the past five years' continuing-education sections of the Annals of Pharmacotherapy, and possible answers were determined on the basis of corresponding articles. The questions were randomly submitted to sci.med.pharmacy from various e-mail accounts over a 10-week period. The same questions were submitted by telephone to randomly selected DICs. The correctness of responses was judged by a panel of four pharmacists. The questions received 31 responses from sci.med. pharmacy and 38 from the DICs. The responses from sci.med.pharmacy received 38 (31%) judgments of correct and the responses from the DICs, 85 (56%). A significantly smaller proportion of drug information responses from the Usenet newsgroup sci.med.pharmacy were judged as being accurate compared with responses from DICs.

A prerequisite for comparative histology of synovial tissue by means of biopsies is insight into the distribution of a marker under study. This investigation focuses on the variation in the presence of T cells and signs of T-cell activation within the rheumatoid joint. For this purpose, multiple slides from several pieces of synovial tissue from different parts of a joint were stained and scored for the expression of CD3, CD25, HLA-DR, Ki67 and interferon-γ. The variation in scores for the presence of T cells and markers of activation was more pronounced in slides prepared from different pieces of tissue than in slides from one piece of tissue. Based on multiple analysis of variance, methods are suggested to establish a reliable overall score for the expression of a certain marker within a joint. Following validation, such methods may prove to be useful by allowing semiquantitative histology of synovial tissue for studies on arthritis.Keywords:Rheumatoid arthritis, Analysis of variance, T cells, Immunohistochemistry.

A prerequisite for comparative histology of synovial tissue by means of biopsies is insight into the distribution of a marker under study. This investigation focuses on the variation in the presence of T cells and signs of T-cell activation within the rheumatoid joint. For this purpose, multiple slides from several pieces of synovial tissue from different parts of a joint were stained and scored for the expression of CD3, CD25, HLA-DR, Ki67 and interferon-γ. The variation in scores for the presence of T cells and markers of activation was more pronounced in slides prepared from different pieces of tissue than in slides from one piece of tissue. Based on multiple analysis of variance, methods are suggested to establish a reliable overall score for the expression of a certain marker within a joint. Following validation, such methods may prove to be useful by allowing semiquantitative histology of synovial tissue for studies on arthritis.
Keywords:Rheumatoid arthritis, Analysis of variance, T cells, Immunohistochemistry.

An electromyographic study of the proximal duodenum in cattle is presented. Changes of motility patterns were studied after induced mechanical obstruction of the descending duodenum in five healthy cows. Special attention was paid to the ratio of antegrade and retrograde motility. Induced duodenal obstruction of which the duration was at most 48 hours, resulted in abrupt disorganisation of the migrating myoelectric complexes; the phases of regular spiking activity disappeared completely or reappeared in a disorganised pattern, and the phases of irregular spiking activity consisted of repetitive groups of spike bursts with prolonged duration and increased propagation velocity. Retrograde peristaltic contractions in the proximal duodenum were observed. Relief of obstruction resulted in a rapid reorganisation of the cyclic pattern of the migrating myoelectric complexes, which indicates normalisation of intestinal activity.

The electromyogram of the abomasum of the adult cow, especially of the corpus abomasi, was studied. For use on the corpus abomasi of the adult cow stainless steel electrodes appeared to last longer than Ni/Cr‐electrodes. In the normal electromyogram of the abomasal body 5 activity patterns were distinguished: 1An electric control activity (ECA), mostly followed by an electric response activity (ERA). On the corpus abomasi these activities occurred simultaneously over the whole corpus and more or less regularly 5.4 ± 0.7 times per minute. Beginning at the incisura angularis, they were propagated towards the pylorus with increasing velocity and regularity, resulting in the arrival at the pylorus of 3.7 ± 0.2 ECA's and ERA's per minute in a very regular rhythm.2A 5 minute rhythm superimposed on the amplitude of the ERA's.3Occasionnally low frequency potential changes were recorded from the corpus abomasi, about 20 to 50 per minute.4Periods of relative inactivity of the corpus abomasi were observed. Short periods of inhibition occurred during the duodenal development of a phase of R.S.A. (regular spike activity). Sometimes longstanding periods of several hours inactivity were observed.5During periods of inactivity a minute rhythm could be observed of small bursts of spike potentials. An electric control activity (ECA), mostly followed by an electric response activity (ERA). On the corpus abomasi these activities occurred simultaneously over the whole corpus and more or less regularly 5.4 ± 0.7 times per minute. Beginning at the incisura angularis, they were propagated towards the pylorus with increasing velocity and regularity, resulting in the arrival at the pylorus of 3.7 ± 0.2 ECA's and ERA's per minute in a very regular rhythm. A 5 minute rhythm superimposed on the amplitude of the ERA's. Occasionnally low frequency potential changes were recorded from the corpus abomasi, about 20 to 50 per minute. Periods of relative inactivity of the corpus abomasi were observed. Short periods of inhibition occurred during the duodenal development of a phase of R.S.A. (regular spike activity). Sometimes longstanding periods of several hours inactivity were observed. During periods of inactivity a minute rhythm could be observed of small bursts of spike potentials. The significance of these findings with respect to motility and flow is discussed. Mit rostfreien Stahlelektroden am Corpus abomasi der Kuh registrierte Muster der myoelektrischen Aktivität Bei der adulten Kuh wurde das Elektromyogramm des Abomasus, insbesondere des Corpus abomasi, untersucht. Dabei erwiesen sich rostfreie Stahlelektroden haltbarer als Ni/Cr‐Elektroden. Im normalen Elektromyogramm des Corpus abomasus konnten 5 Aktivitätsmuster unterschieden werden: 1Eine elektrische Schrittmacher‐Aktivität (ECA), der meist eine Aktivität der elektrischen Antworten (ERA) folgte. Am Corpus abomasi traten diese Aktivitäten entlang des gesamten Corpus gleichzeitig und mehr oder weniger regelmäßig 5,4 ± 0,7mal pro Minute auf. Sic begannen an der Incisura angularis und pflanzten sich Richtung Pylorus mit zunehmender Geschwindigkeit und Regelmäßigkeit fort, so daß 3,7 ± 0,2 ECA und ERA pro Minute sehr regelmäßig den Pylorus erreichten.2Ein 5 min‐Rhythmus, der sich der ERA‐Amplitude überlagerte.3Gelegentlich wurden am Corpus abomasi niederfrequente Potentialschwankungen registriert (etwa 20 bis 50 pro Minute).4Am Corpus abomasi wurden ferner Perioden relativer Inaktivität beobachtet. Eine kurzfristige Hemmung ergab sich während der Entwicklung einer Phase der regelmäßigen “Spike”‐Aktivität des Duodenums. Manchmal wurden auch mehrere Stunden andauernde Perioden der Inaktivität beobachtet.5Während der Inaktivitätsperioden konnte ein Minuten‐Rhythmus kleiner Salven von “Spike”‐Potentialen beobachtet werden.Die Bedeutung dieser Befunde für die Motilität und den Digesta‐Fluß wird diskutiert. Eine elektrische Schrittmacher‐Aktivität (ECA), der meist eine Aktivität der elektrischen Antworten (ERA) folgte. Am Corpus abomasi traten diese Aktivitäten entlang des gesamten Corpus gleichzeitig und mehr oder weniger regelmäßig 5,4 ± 0,7mal pro Minute auf. Sic begannen an der Incisura angularis und pflanzten sich Richtung Pylorus mit zunehmender Geschwindigkeit und Regelmäßigkeit fort, so daß 3,7 ± 0,2 ECA und ERA pro Minute sehr regelmäßig den Pylorus erreichten. Ein 5 min‐Rhythmus, der sich der ERA‐Amplitude überlagerte. Gelegentlich wurden am Corpus abomasi niederfrequente Potentialschwankungen registriert (etwa 20 bis 50 pro Minute). Am Corpus abomasi wurden ferner Perioden relativer Inaktivität beobachtet. Eine kurzfristige Hemmung ergab sich während der Entwicklung einer Phase der regelmäßigen “Spike”‐Aktivität des Duodenums. Manchmal wurden auch mehrere Stunden andauernde Perioden der Inaktivität beobachtet. Während der Inaktivitätsperioden konnte ein Minuten‐Rhythmus kleiner Salven von “Spike”‐Potentialen beobachtet werden. Die Bedeutung dieser Befunde für die Motilität und den Digesta‐Fluß wird diskutiert.

Context. Radiative feedback plays a crucial role in the formation of massive stars. The implementation of a fast and accurate description of the proceeding thermodynamics in pre-stellar cores and evolving accretion disks is therefore a main effort in current hydrodynamics simulations.Aims. We introduce our newly implemented three-dimensional frequency dependent radiation transport algorithm for hydrodynamics simulations of spatial configurations with a dominant central source.Methods. The module combines the advantage of the speed of an approximate flux limited diffusion (FLD) solver in the one-temperature approach, which is valid in the static diffusion limit, with the high accuracy of a frequency dependent first order ray-tracing routine. The ray-tracing routine especially compensates the introduced inaccuracies by standard approximate FLD solvers in transition regions from optically thin to thick and yields the correct optical depths for the frequency dependent stellar irradiation. Both components of our module make use of realistic tabulated dust opacities. The module is parallelized for distributed memory machines based on the message passing interface standard. We implemented the module in the three-dimensional high-order magneto-hydrodynamics code Pluto. Results. We prove the viability of the scheme in a standard radiation benchmark test compared to a full frequency dependent Monte-Carlo based radiative transfer code. The setup includes a central star, a circumstellar flared disk, as well as an envelope. The test is performed for different optical depths. Considering the frequency dependence of the stellar irradiation, the temperature distributions can be described precisely in the optically thin, thick, and irradiated transition regions. Resulting radiative forces onto dust grains are reproduced with high accuracy. The achievable parallel speedup of the method imposes no restriction on further radiative (magneto-) hydrodynamics simulations.Conclusions. The proposed approximate radiation transport method enables frequency dependent radiation hydrodynamics studies of the evolution of pre-stellar cores and circumstellar accretion disks around an evolving massive star in a highly efficient and accurate manner.

Context. Radiative feedback plays a crucial role in the formation of massive stars. The implementation of a fast and accurate description of the proceeding thermodynamics in pre-stellar cores and evolving accretion disks is therefore a main effort in current hydrodynamics simulations.