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1.
Eur Phys J C Part Fields ; 78(12): 1006, 2018.
Article in English | MEDLINE | ID: mdl-30872956

ABSTRACT

One of the main objectives of the ANTARES telescope is the search for point-like neutrino sources. Both the pointing accuracy and the angular resolution of the detector are important in this context and a reliable way to evaluate this performance is needed. In order to measure the pointing accuracy of the detector, one possibility is to study the shadow of the Moon, i.e. the deficit of the atmospheric muon flux from the direction of the Moon induced by the absorption of cosmic rays. Analysing the data taken between 2007 and 2016, the Moon shadow is observed with 3.5 σ statistical significance. The detector angular resolution for downward-going muons is 0 . 73 ∘ ± 0 . 14 ∘ . The resulting pointing performance is consistent with the expectations. An independent check of the telescope pointing accuracy is realised with the data collected by a shower array detector onboard of a ship temporarily moving around the ANTARES location.

2.
Eur Phys J C Part Fields ; 77(6): 419, 2017.
Article in English | MEDLINE | ID: mdl-28775667

ABSTRACT

A novel algorithm to reconstruct neutrino-induced particle showers within the ANTARES neutrino telescope is presented. The method achieves a median angular resolution of [Formula: see text] for shower energies below 100 TeV. Applying this algorithm to 6 years of data taken with the ANTARES detector, 8 events with reconstructed shower energies above 10 TeV are observed. This is consistent with the expectation of about 5 events from atmospheric backgrounds, but also compatible with diffuse astrophysical flux measurements by the IceCube collaboration, from which 2-4 additional events are expected. A [Formula: see text] C.L. upper limit on the diffuse astrophysical neutrino flux with a value per neutrino flavour of [Formula: see text] is set, applicable to the energy range from 23 TeV to 7.8 PeV, assuming an unbroken [Formula: see text] spectrum and neutrino flavour equipartition at Earth.

3.
Sci Rep ; 7: 45517, 2017 04 12.
Article in English | MEDLINE | ID: mdl-28401960

ABSTRACT

Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems.

4.
Eur J Clin Microbiol Infect Dis ; 33(6): 949-55, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24338093

ABSTRACT

With the emergence and growing complexity of bacterial drug resistance, rapid and reliable susceptibility testing has become a topical issue. Therefore, new technologies that assist in predicting the effectiveness of empiric antibiotic therapy are of great interest. Although the use of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) for the rapid detection of antibiotic resistance is an attractive option, the current methods for MALDI-TOF MS susceptibility testing are restricted to very limited conditions. Here, we describe a technique that may allow for rapid susceptibility testing to an extent that is comparable to phenotypic methods. The test was based on a stable isotope labelling by amino acids in cell culture (SILAC)-like approach. This technique was used to visualise the growth of bacteria in the presence of an antibiotic. Pseudomonas aeruginosa was chosen as the model organism, and strains were incubated in normal medium, medium supplemented with (13)C6-(15) N2-labelled lysine and medium supplemented with labelled lysine and antibiotic. Peak shifts occurring due to the incorporation of the labelled amino acids were detected by MALDI-TOF MS. Three antibiotics with different mechanisms of action, meropenem, tobramycin and ciprofloxacin, were tested. A semi-automated algorithm was created to enable rapid and unbiased data evaluation. With the proposed test, a clear distinction between resistant and susceptible isolates was possible for all three antibiotics. The application of SILAC technology for the detection of antibiotic resistance may contribute to accelerated and reliable susceptibility testing.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Isotopes/metabolism , Mass Spectrometry/methods , Pseudomonas aeruginosa/drug effects , Amino Acids/metabolism , Ciprofloxacin/pharmacology , Culture Media/chemistry , Isotope Labeling , Meropenem , Microbial Sensitivity Tests/methods , Thienamycins/pharmacology , Time Factors , Tobramycin/pharmacology
5.
Colorectal Dis ; 13(12): e403-10, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21812896

ABSTRACT

AIM: Low and ultralow anterior resection for rectal cancer with colorectal or coloanal anastomosis does not compromise oncological results compared with abdominoperineal excision. Although avoidance of a permanent colostomy is regarded as beneficial for a patient's quality of life (QoL), patients undergoing sphincter-sparing surgery may develop a number of functional problems. A colonic pouch significantly improves functional outcome after rectal resection and low anastomosis and may positively influence QoL. The aim of this study was to compare QoL in long-term survivors who underwent ultralow anterior resection with total mesorectal excision and colonic J-pouch anastomosis (CPA) with patients treated with abdominoperineal excision (APE) and end colostomy for rectal cancer. METHOD: The medical records from our institution's prospectively maintained rectal cancer database of 151 patients who underwent surgery for ultralow rectal cancer from 2001 to 2007 were analysed. QoL in 59 eligible patients was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 core and Colorectal Cancer 29. Results were compared for patients with CPA and APE. RESULTS: The median follow-up in the 59 patients was 74 (37-119) months. QoL was good in all patients, but it was better in CPA than in APE patients. Global health status (P = 0.009), physical functioning (P = 0.0002), role functioning (P = 0.03), cognitive functioning (P = 0.046), social functioning (P = 0.002), body image (P = 0.053), embarrassment (P = 0.002) and urinary frequency (P = 0.003) were significantly improved for patients with CPA. CONCLUSION: QoL after rectal resection and CPA was better than after APE in several respects. However, QoL should not be regarded as an isolated concept but rather as one of several possible clinical outcomes of interest.


Subject(s)
Colonic Pouches , Colostomy/psychology , Proctocolectomy, Restorative/psychology , Quality of Life/psychology , Rectal Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Body Image , Cognition , Colonic Pouches/physiology , Female , Follow-Up Studies , Health Status , Humans , Male , Middle Aged , Shame , Social Participation/psychology , Surveys and Questionnaires , Time Factors
6.
Phys Rev Lett ; 103(13): 132301, 2009 Sep 25.
Article in English | MEDLINE | ID: mdl-19905504

ABSTRACT

We report first results on a deep subthreshold production of the doubly strange hyperon Xi;{-} in a heavy-ion reaction. At a beam energy of 1.76A GeV the reaction Ar + KCl was studied with the High Acceptance Di-Electron Spectrometer at SIS18/GSI. A high-statistics and high-purity Lambda sample was collected, allowing for the investigation of the decay channel Xi;{-} --> Lambdapi;{-}. The deduced Xi;{-}/(Lambda + Sigma;{0}) production ratio of (5.6 +/- 1.2_{-1.7};{+1.8}) x 10;{-3} is significantly larger than available model predictions.

7.
Endoscopy ; 39(6): 497-501, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17554643

ABSTRACT

BACKGROUND AND STUDY AIMS: An endocytoscope system (ECS) has recently been developed with the possibility of super-high magnification of gastrointestinal mucosa, thus allowing in vivo imaging of living cells. The aim of the present study was to assess the potential of ECS in the prediction of histology in both normal gastrointestinal mucosa and neoplastic lesions. PATIENTS AND METHODS: In total, 76 patients (57 men, 19 women; age range 37-86 years) with neoplastic lesions in the esophagus, stomach, or colon were enrolled into the study and underwent esophagogastroduodenoscopy or colonoscopy. After staining with 1% methylene blue, the mucosa was examined with the ECS probe (x 450 and x 1100 magnification), and video sequences were recorded on video disk. Biopsies from the examined areas were taken for histology and served as the gold standard. The endocytoscope video sequences were evaluated by two blinded pathologists. Finally the results were compared with those resulting from the evaluation of an experienced endoscopist who was aware of the macroscopic endoscopic pictures and the endocytoscope image results. RESULTS: A total of 25 patients with esophageal lesions, 28 patients with colonic lesions, and 23 patients with gastric lesions were examined. The sensitivity and specificity for the evaluation of the blinded pathologists was 81% and 100%, respectively, in the esophagus, 56% and 89% in the stomach, and 79% and 90% in the colon. If an endoscopist evaluated the endocytoscopic pictures in combination with the macroscopic endoscopic images sensitivity and specificity increased significantly. CONCLUSIONS: First experiences with ECS show good sensitivity rates even by blinded assessment for esophageal and colonic lesions. Sensitivity for neoplastic lesions in the stomach is lower because of gastric mucous secretion. Combining the endoscopic and cytoscopic appearance of the lesion may further enhance the diagnostic value of the method.


Subject(s)
Endoscopy, Digestive System/methods , Gastrointestinal Neoplasms/pathology , Gastrointestinal Tract/pathology , Microscopy/methods , Mucous Membrane/pathology , Adult , Aged , Aged, 80 and over , Biopsy , Colon/pathology , Colonic Neoplasms/pathology , Esophageal Neoplasms/pathology , Esophagus/pathology , Female , Humans , Intestinal Mucosa/pathology , Male , Middle Aged , Predictive Value of Tests , Stomach Neoplasms/pathology
8.
Phys Rev Lett ; 98(5): 052302, 2007 Feb 02.
Article in English | MEDLINE | ID: mdl-17358850

ABSTRACT

The invariant-mass spectrum of e+e- pairs produced in 12C+12C collisions at an incident energy of 2 GeV per nucleon has been measured for the first time. The measured pair production probabilities span over 5 orders of magnitude from the pi(0)-Dalitz to the rho/omega invariant-mass region. Dalitz decays of pi(0) and eta account for all the yield up to 0.15 GeV/c(2), but for only about 50% above this mass. A comparison with model calculations shows that the excess pair yield is likely due to baryon-resonance and vector-meson decays. Transport calculations based on vacuum spectral functions fail, however, to describe the entire mass region.

9.
Z Gerontol Geriatr ; 40(1): 31-6, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17318729

ABSTRACT

UNLABELLED: Loss of appetite is an important causal factor for malnutrition in the elderly, and age-associated changes of hormone levels seem to be of great relevance in this regard. At present there has been no study exploring the role of the appetite stimulating hormone ghrelin in geriatric hospital patients. STUDY POPULATION: 121 (f 82, m 39) patients from two geriatric wards of our hospital. Mean age was 80.2+/-7.7 years. RESULTS: The basal ghrelin level (mean 158.43+/-144.02 pg/ml) showed no gender difference. No association with the age of the patients could be demonstrated. There was an inverse correlation of basal ghrelin with BMI, upper arm circumference, triceps skin fold, basal leptin and insulin. No correlation between established screening/assessment tools for malnutrition - Mini Nutritional Assessment (MNA), Subjective Global Assessment (SGA), Nutritional Risk Screening (NRS) - could be shown. Even after grouping the ghrelin levels into six different disease categories, no significant difference could be shown between them. CONCLUSION: For our patients aged 67 to 94, no correlation with age could be shown. Nevertheless the basal level of ghrelin is substantially lower when compared to a younger population with similar BMI, while the anorectic hormone leptin shows no substantial difference. This causes a more anorectic hormonal constellation which may contribute to the loss of appetite in geriatric patients.


Subject(s)
Aging/blood , Body Constitution , Geriatric Assessment/methods , Leptin/blood , Malnutrition/blood , Malnutrition/diagnosis , Nutrition Assessment , Peptide Hormones/blood , Age Distribution , Aged , Aged, 80 and over , Anthropometry/methods , Biomarkers/blood , Female , Geriatric Assessment/statistics & numerical data , Germany/epidemiology , Ghrelin , Health Services for the Aged/statistics & numerical data , Hospitalization/statistics & numerical data , Humans , Male , Malnutrition/epidemiology , Nutritional Status
10.
Z Gastroenterol ; 44(3): 239-44, 2006 Mar.
Article in German | MEDLINE | ID: mdl-16514569

ABSTRACT

We report on three patients with severe gastrointestinal bleeding arising from aortoenteric fistula. Two patients presented with a secondary aortoduodenal fistula. In the first case bleeding occurred 8 months after aortobifemoral graft implantation. In the second patient aortobiliacal graft implantation was performed 22 years before. In the third case the aortoenteric fistula was primary and was caused by an abdominal aortic aneurysm without prior vascular intervention. In the first case diagnosis was made by urgent endoscopy visualizing ongoing bleeding from the duodenal fistula. In the two other patients urgent endoscopy and CT as well could not demonstrate the bleeding source. Aortoenteric fistula was diagnosed endoscopically during severe rebleeding some hours later. Two patients underwent surgery with implantation of an axillobifemoral bypass; the third patient declined further intervention and died. The course shows that aortoduodenal fistula can present with severe but intermittent gastrointestinal bleeding making the diagnosis in the non-bleeding interval difficult. In patients with severe gastrointestinal bleeding and a history of aortic disease (aneurysm, prior aortic graft repair or stenting) an aortoduodenal fistula should be suspected and the indication for surgical intervention should be considered early in spite of negative results of endoscopy and CT.


Subject(s)
Aortic Diseases/complications , Duodenal Diseases/complications , Endoscopy, Gastrointestinal/methods , Gastrointestinal Hemorrhage/etiology , Intestinal Fistula/complications , Aged , Aortic Diseases/pathology , Diagnosis, Differential , Duodenal Diseases/pathology , Gastrointestinal Hemorrhage/pathology , Humans , Intestinal Fistula/pathology , Male , Middle Aged
15.
Onkologie ; 25(3): 262-6, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12119461

ABSTRACT

BACKGROUND: The observation of a familial accumulation of ductal pancreatic adenocarcinoma (PC) and the increased risk for PC in certain hereditary tumor syndromes point to a genetic predisposition for PC. In order to evaluate the characteristics of familial PC, a German national case collection for familial pancreas cancer (FaPaCa) was established. PATIENTS AND METHODS: In FaPaCa, families of patients with PC are being collected, who have at least 1 first-degree relative with PC or with malignant melanoma. Histopathologic verification of tumor diagnoses, acquisition of clinical data, and full genetic counselling are prerequisites for the enrollment of PC families in FaPaCa. RESULTS: So far, 21 families fulfilled the criteria for partaking in FaPaCa. In 11 families, PC represented the sole tumor entity. Additional tumors included malignant melanoma in 5, breast cancer in 3, and prostatic, colon or lung cancer in 2 families. Compared to the preceding generation, a younger age at diagnosis of PC was observed in the offspring of PC patients (offspring median 53 years vs. parents median 75.5 years). CONCLUSION: The association of PC and breast cancer, and of PC and malignant melanoma suggests predisposing mutations in the BRCA2 or CDKN2A genes in about one third of the FaPaCa families. Mutational analyses in both candidate genes may help to identify individuals who are at an increased risk for developing PC. A shift towards a younger age at diagnosis in our PC families may indicate genetic anticipation and/or changes of patterns of exogenous risk factors.


Subject(s)
Carcinoma, Pancreatic Ductal/genetics , Pancreatic Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Anticipation, Genetic/genetics , Carcinoma, Pancreatic Ductal/diagnosis , Carcinoma, Pancreatic Ductal/pathology , Female , Genetic Counseling , Genetic Predisposition to Disease/genetics , Humans , Male , Melanoma/diagnosis , Melanoma/genetics , Melanoma/pathology , Middle Aged , Neoplasms, Multiple Primary/diagnosis , Neoplasms, Multiple Primary/genetics , Neoplasms, Multiple Primary/pathology , Neoplastic Syndromes, Hereditary/diagnosis , Neoplastic Syndromes, Hereditary/genetics , Neoplastic Syndromes, Hereditary/pathology , Pancreas/pathology , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/pathology , Pedigree , Risk , Skin Neoplasms/diagnosis , Skin Neoplasms/genetics , Skin Neoplasms/pathology
17.
Transpl Int ; 13 Suppl 1: S555-7, 2000.
Article in English | MEDLINE | ID: mdl-11112072

ABSTRACT

Questions as to the critical stress factor and primary targets of cold ischemia/reperfusion (CIR) injury were addressed by comparing mitochondrial defects caused by (1) CIR injury and (2) intracellular Ca2+ overload. CIR was simulated in transformed human umbilical vein endothelial cell cultures (tEC) by 8 h cold anoxia in University of Wisconsin solution and reoxygenation at 37 degrees C. Intracellular Ca2+ concentrations were changed by permeabilization of suspended cells with digitonin in culture medium (RPMI, 0.4 mM Ca2+). Binding of free Ca2+ by ethylene glycol-bis(beta-aminoethylether)-N,N,N',N'-tetraacetic acid in RPMI or mitochondrial incubation medium served as controls. Extracellular Ca2+ protected the cell membrane against permeabilization. Mitochondrial functions were determined before and after permeabilization of the cell membrane. After CIR, mitochondrial respiratory capacity declined, but oxygen consumption remained coupled to adenosine triphosphate (ATP) production. In contrast, Ca2+ overload caused uncoupling of mitochondrial respiration. High intracellular Ca2+ overload, therefore, does not reproduce cold ischemia/reperfusion injury in endothelial cells.


Subject(s)
Calcium/physiology , Endothelium, Vascular/cytology , Mitochondria/physiology , Reperfusion Injury , Adenosine , Allopurinol , Calcium/pharmacology , Cell Hypoxia , Cell Line, Transformed , Cell Membrane Permeability , Cells, Cultured , Cold Temperature , Egtazic Acid , Endothelium, Vascular/physiology , Glutathione , Humans , Insulin , Ischemia , Organ Preservation Solutions , Oxygen Consumption , Raffinose , Umbilical Veins
18.
Arterioscler Thromb Vasc Biol ; 20(3): 617-23, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10712382

ABSTRACT

Recent investigations indicate that the initial event in the pathogenesis of atherosclerosis involves an (auto)immunologic injury to the vessel wall. Heat shock proteins (hsps), which are expressed on the endothelial cell surface, constitute possible autoantigens. After being exposed to shear stress of 30 dyne/cm(2) in vitro by means of a rotational viscometer, human umbilical vein endothelial cells were immunohistochemically stained for hsp 60 by the monoclonal antibody ML-30; static control cells were negative. Maximal hsp 60 induction was observed after 12 hours of hemodynamic stress. In Northern blots, the level of hsp 60 mRNA was markedly increased after only 1 hour of shear stress in human umbilical vein endothelial cells compared with static control cells. In vivo investigations in Lewis rats confirmed these in vitro findings: the intima and media of frozen sections of the right common carotid artery exposed to increased wall shear stress (after ligation of the left common carotid artery) were stained for hsp 60. The vessel wall of the left low-shear-stress-exposed side was negative. These findings demonstrate that shear stress results in hsp 60 induction in endothelial cells in vivo and in vitro, providing the prerequisite for humoral and cellular reactions to endothelial hsp in the earliest stages of atherosclerosis.


Subject(s)
Arteriosclerosis/immunology , Chaperonin 60/genetics , Chaperonin 60/immunology , Endothelium, Vascular/immunology , Animals , Arteriosclerosis/genetics , Autoantigens/genetics , Blood Pressure , Blotting, Northern , Carotid Artery, Common/cytology , Carotid Artery, Common/physiopathology , Cells, Cultured , Chaperonin 60/analysis , Culture Media/pharmacology , Endothelium, Vascular/chemistry , Endothelium, Vascular/cytology , Female , Gene Expression/immunology , Humans , Ligation , Perfusion , RNA, Messenger/analysis , Rats , Rats, Inbred Lew , Staining and Labeling , Stress, Mechanical , Umbilical Veins/cytology , Viscosity
19.
Astrophys J ; 527(1): L39-L42, 1999 Dec 10.
Article in English | MEDLINE | ID: mdl-10566994

ABSTRACT

Hydrodynamic simulations of the merger of stellar mass black hole-neutron star binaries are compared with mergers of binary neutron stars. The simulations are Newtonian but take into account the emission and back-reaction of gravitational waves. The use of a physical nuclear equation of state allows us to include the effects of neutrino emission. For low neutron star-to-black hole mass ratios, the neutron star transfers mass to the black hole during a few cycles of orbital decay and subsequent widening before finally being disrupted, whereas for ratios near unity the neutron star is destroyed during its first approach. A gas mass between approximately 0.3 and approximately 0.7 M middle dot in circle is left in an accretion torus around the black hole and radiates neutrinos at a luminosity of several times 1053 ergs s-1 during an estimated accretion timescale of about 0.1 s. The emitted neutrinos and antineutrinos annihilate into e+/- pairs with efficiencies of 1%-3% and rates of up to approximately 2x1052 ergs s-1, thus depositing an energy Enunu&d1; less, similar1051 ergs above the poles of the black hole in a region that contains less than 10-5 M middle dot in circle of baryonic matter. This could allow for relativistic expansion with Lorentz factors around 100 and is sufficient to explain apparent burst luminosities Lgamma approximately Enunu&d1;&solm0;&parl0;fOmegatgamma&parr0; up to several times 1053 ergs s-1 for burst durations tgamma approximately 0.1-1 s, if the gamma emission is collimated in two moderately focused jets in a fraction fOmega=2deltaOmega&solm0;&parl0;4pi&parr0; approximately 1&solm0;100-(1/10) of the sky.

20.
Luminescence ; 14(2): 91-8, 1999.
Article in English | MEDLINE | ID: mdl-10398566

ABSTRACT

In order to cope with large amounts of samples for chemiluminescence (CL), vials were replaced with microplates. Although various types of plates have been commercially available for quite some time and the free-plate mode is advocated by the producer of the counter, little is known about their impact on the outcome of CL measurements. We tested two different 24-well microplates and six different 96-well microplates in two different luminometers, and results were compared with those achieved with vials. Before these comparative tests, we attempted to optimize measurement conditions. CL sensitivity was highest with luminol concentrations of 0.8-3.3 micromol/L, PMA concentrations of 0.06-80 micromol/L, a pH value of 10 and a temperature of 20 degrees C. An indirect correlation was found between fluid volume and yield in counts: the lower the volume, the higher the counts. With regard to sensitivity and cross-talk, the 96-well Isoplatetrade mark was superior to all other plates tested. While all white plates tested gave acceptable results, usage of the black 96-well plates resulted in an extremely low sensitivity. Plates designed for cell culturing gave even lower counts and a cross-talk of up to 31%. All attempts to reduce cross-talk and improve sensitivity, such as aluminium foil or grids, irrespective of the position of the photomultiplier, did not give results comparable to the original 96-well isoplate. Our results suggest that, with the exception of black 96-well microplates and cell culture plates, all other plates tested have a sufficient sensitivity when compared to vials and acceptable cross-talk, the 96-well Isoplatetrade mark being the best. Both types of luminometers used gave reproducible results, Wallac having a somewhat higher sensitivity, Canberra Packard somewhat less cross-talk.


Subject(s)
Luminescent Measurements , Phagocytes/physiology , Humans , Kinetics , Phagocytes/drug effects , Photometry/instrumentation , Photometry/methods , Sensitivity and Specificity , Tetradecanoylphorbol Acetate/pharmacology
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