Genetic vs community diversity patterns of macrobenthic species: preliminary results from the lagoonal ecosystem

1 - The use of molecular data derived from multispecies assemblages in order to test ecological theory has only recently been introduced in the scientific literature.2 - As a first step, we compared patterns of abiotic environment, polychaeta distribution and their genetic diversity in five lagoon ecosystems in Greece. Our results confirm the hypothesis that higher genetic diversity is expected in the populations of the species occurring in the transitional waters rather than of those occurring in the marine environment.3 - Patterns derived from the polychaete community level and from the mitochondrial DNA (16S rRNA) obtained from Nephtys hombergii and Hediste diversicolor showed convergence, indicating the potential use of molecular matrices as surrogates in community analysis.4 - Finally, the high correlation between the genetic diversity pattern of H. diversicolor and the phosphorus concentration in the sediments may imply the broadening of the hierarchic-response-tostress hypothesis towards lower than species level

Ekspresija i obrada somatostatina u gušterači u razvoju i u duktalnom adenokarcinomu gušterače

Somatostatin is a gastrointestinal peptide hormone that inhibits growth of pancreatic cancer as reported by an increasing body of evidence. Yet this is not always the case. To clarify the controversy we aimed to identify the expression of somatostatin in developing human embryonic pancreatic tissue and pancreatic adenocarcinoma given that somatostatin positive cells were shown either into primitive pancreatic ductal epithelium or into pancreatic carcinoma. Tissue sections representing pancreatic fetal specimens (n=15) and ductal pancreatic adenocarcinoma specimens (n=15) were assessed using immunohistochemical methods for somatostatin expression. Normal primitive exocrine ductal epithelium and endocrine epithelium showed a definite, statistically significant, higher expression of somatostatin over neoplastic pancreatic tissue of mixed (ductal-endocrine) and pure ductal type (p1=0.021, p2=0.001, p3<0.0001and p4=0.003 respectively) during the 8th to the 10th week. No statistically significantly different expression of somatostatin in the mantle zone of the islets over neoplastic tissue of mixed (p5=0.16) and pureductal type (p6=0.65), from the 13th to the 24th week was demonstrated. Pancreatic cancer cells can express somatostatin in a model that reproduces the normal expression of the peptide by d-cells during embryonal organogenesis. Therapy aimed at pancreatic cancer must be targeted to somatostatin and analogues as a potential adjuvant novel option.Somatostatin je probavni peptidni hormon koji suzbija rast raka gušterače, za što postoji sve više dokaza. No to se ne događa uvijek. Cilj studije bio je utvrditi ekspresiju somatostatina u ljudskom embrijskom tkivu gušterače u razvoju i u adenokarcinomu gušterače, s tim da su na somatostatin pozitivne stanice dokazane ili u primitivnom duktalnom epitelu gušterače ili u karcinomu gušterače. Tkivni isječci koji su predstavljali uzorke fetalne gušterače (n=15) i uzorke adenokarcinoma gušterače (n=15) ispitani su pomoću imunohistokemijskih metoda za ekspresiju somatostatina. Normalan primitivni egzokrini duktalni epitel i endokrini epitel pokazao je konačnu, statistički značajno višu ekspresiju somatostatina iznad neoplastičnog tkiva gušterače miješanog (duktalno-endokrinog) i čistog duktalnog tipa (p1=0,021, P2=0,001, p3<0,0001 odnosno p4=0,003) tijekom 8. do 10. tjedna. Nije dokazana statistički značajno različita ekspresija somatostatina u ovojnom sloju (mantle zone, mantle layer) otočića iznadneoplastičnog tkiva miješanog (p5=0,16) i čistog duktalnog tipa (p6=0,65) od 13. do 24. tjedna. Dakle, stanice raka gušterače mogu izražavati somatostatin na naein koji ponavlja normalnu d-staničnu ekspresiju peptida za vrijeme embrijske organogeneze. Liječenje zbog raka gušterače usmjereno na somatostatin i njegove analoge moglo bi predstavljati novu mogućnosti adjuvantne terapije

Prevalence, predictors and prognostic implications of PR interval prolongation in patients with heart failure

Aims: To determine the prevalence, incidence, predictors and prognostic implications of PR interval prolongation in patients referred with suspected heart failure. Methods and Results: Consecutive patients referred with suspected heart failure were prospectively enrolled. After excluding patients with implantable cardiac devices and atrial fibrillation, 1420 patients with heart failure and reduced ejection fraction (HeFREF) [age: median 71 (interquartile range IQR: 63-78) years; men: 71%; NT-ProBNP: 1319 (583-3378) ng/L], 1094 with heart failure and normal ejection fraction (HeFNEF) [age: 76 (70-82) years; men: 47%; NT-ProBNP: 547 (321-1171) ng/L], and 1150 without heart failure [age: 68 (60-75) years; men: 51%; NT-ProBNP: 86 (46-140) ng/L] were included. The prevalence of first degree heart block [heart-rate corrected PR interval (PRc) >200 ms] was higher in patients with heart failure (21% HeFREF, 20% HeFNEF, 9% without heart failure). In patients with HeFREF or HeFNEF, longer baseline PRc was associated with greater age, male sex, and longer QRS duration and, in those with HeFREF, treatment with amiodarone or digoxin. Patients with heart failure in the longest PRc quartile had worse survival compared to shorter PRc quartiles but PRc was not independently associated with survival in multivariable analysis. For patients without heart failure, shorter baseline PRc was independently associated with worse survival. Conclusion: PRc prolongation is common in patients with HeFREF or HeFNEF and associated with worse survival, although not an independent predictor of outcome. The results of clinical trials investigating the therapeutic potential of shortening the PR interval by pacing are awaited

Diffuse large B-cell lymphoma arising from a multicentric mixed variant of Castleman's disease

This case report describes a patient with multicentric mixed type Castleman\u2032s disease and concomitant non-Hodgkin\u2032s lymphoma of diffuse large B cell type in the neck. Multicentric CD is a systemic illness with disseminated lymphadenopathy; its aggressive and usually fatal course is associated with infectious complications and risk for malignant tumors, such as lymphoma or Kaposi sarcoma

System Test of the ATLAS Muon Spectrometer in the H8 Beam at the CERN SPS

An extensive system test of the ATLAS muon spectrometer has been performed in the H8 beam line at the CERN SPS during the last four years. This spectrometer will use pressurized Monitored Drift Tube (MDT) chambers and Cathode Strip Chambers (CSC) for precision tracking, Resistive Plate Chambers (RPCs) for triggering in the barrel and Thin Gap Chambers (TGCs) for triggering in the end-cap region. The test set-up emulates one projective tower of the barrel (six MDT chambers and six RPCs) and one end-cap octant (six MDT chambers, A CSC and three TGCs). The barrel and end-cap stands have also been equipped with optical alignment systems, aiming at a relative positioning of the precision chambers in each tower to 30-40 micrometers. In addition to the performance of the detectors and the alignment scheme, many other systems aspects of the ATLAS muon spectrometer have been tested and validated with this setup, such as the mechanical detector integration and installation, the detector control system, the data acquisition, high level trigger software and off-line event reconstruction. Measurements with muon energies ranging from 20 to 300 GeV have allowed measuring the trigger and tracking performance of this set-up, in a configuration very similar to the final spectrometer. A special bunched muon beam with 25 ns bunch spacing, emulating the LHC bunch structure, has been used to study the timing resolution and bunch identification performance of the trigger chambers. The ATLAS first-level trigger chain has been operated with muon trigger signals for the first time

Contrast Enhanced Micro-Computed Tomography Resolves the 3-Dimensional Morphology of the Cardiac Conduction System in Mammalian Hearts

The general anatomy of the cardiac conduction system (CCS) has been known for 100 years, but its complex and irregular three-dimensional (3D) geometry is not so well understood. This is largely because the conducting tissue is not distinct from the surrounding tissue by dissection. The best descriptions of its anatomy come from studies based on serial sectioning of samples taken from the appropriate areas of the heart. Low X-ray attenuation has formerly ruled out micro-computed tomography (micro-CT) as a modality to resolve internal structures of soft tissue, but incorporation of iodine, which has a high molecular weight, into those tissues enhances the differential attenuation of X-rays and allows visualisation of fine detail in embryos and skeletal muscle. Here, with the use of a iodine based contrast agent (I2KI), we present contrast enhanced micro-CT images of cardiac tissue from rat and rabbit in which the three major subdivisions of the CCS can be differentiated from the surrounding contractile myocardium and visualised in 3D. Structures identified include the sinoatrial node (SAN) and the atrioventricular conduction axis: the penetrating bundle, His bundle, the bundle branches and the Purkinje network. Although the current findings are consistent with existing anatomical representations, the representations shown here offer superior resolution and are the first 3D representations of the CCS within a single intact mammalian heart

High resolution 3-Dimensional imaging of the human cardiac conduction system from microanatomy to mathematical modeling

Cardiac arrhythmias and conduction disturbances are accompanied by structural remodelling of the specialised cardiomyocytes known collectively as the cardiac conduction system. Here, using contrast enhanced micro-computed tomography, we present, in attitudinally appropriate fashion, the first 3-dimensional representations of the cardiac conduction system within the intact human heart. We show that cardiomyocyte orientation can be extracted from these datasets at spatial resolutions approaching the single cell. These data show that commonly accepted anatomical representations are oversimplified. We have incorporated the high-resolution anatomical data into mathematical simulations of cardiac electrical depolarisation. The data presented should have multidisciplinary impact. Since the rate of depolarisation is dictated by cardiac microstructure, and the precise orientation of the cardiomyocytes, our data should improve the fidelity of mathematical models. By showing the precise 3-dimensional relationships between the cardiac conduction system and surrounding structures, we provide new insights relevant to valvar replacement surgery and ablation therapies. We also offer a practical method for investigation of remodelling in disease, and thus, virtual pathology and archiving. Such data presented as 3D images or 3D printed models, will inform discussions between medical teams and their patients, and aid the education of medical and surgical trainees

Virtual reality reusable e-resources for clinical skills training: a mixed-methods evaluation

Virtual reality has long existed, but its wider adoption in education is recent. Studies informed by theoretical underpinned co-creation frameworks and utilization of theoretical informed evaluations are scarce in literature. Thus, this study internationally evaluated the efficacy of three virtual reality reusable e-resources (VRReRs), co-created based on the ASPIRE framework, for teaching clinical skills to university students. The study followed a mixed-methods approach, combining SUS, SUS Presence Questionnaire, TAM, and UTAUT2 with a focus group discussion. Additionally, for one VRReR, a quantitative pre/post evaluation of knowledge and comparison with lecture notes followed. Results demonstrated moderately to highly usability, effectively facilitated a strong sense of presence, confidence while using them, and willingness to continue using VRReRs in the future, while increased knowledge of the learners, highlighted their effectiveness. Although some usability issues were identified, these were considered easy to address. This work evidence, in an international context, that co-created VR resources are highly acceptable and effective, similar to other types of digital or traditional resources developed through participatory inquiry paradigm. By leveraging the benefits of VR technology, VRReRs have the potential to transform and enhance the learning experience in the field of clinical skills, ultimately advancing the digitalization of higher education