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1.
Rhinology ; 61(1): 12-23, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36323438

ABSTRACT

BACKGROUND: Chemosensory dysfunction (CD) has been reported as a common symptom of SARS-CoV-2 infection, but it is not well understood whether and for how long changes of smell, taste and chemesthesis persist in infected individuals. METHODOLOGY: Unselected adult residents of the German federal state of Schleswig-Holstein with Polymerase Chain Reaction (PCR)-test-confirmed SARS-CoV-2 infection were invited to participate in this large cross-sectional study. Data on the medical history and subjective chemosensory function of participants were obtained through questionnaires and visual analogue scales (VAS). Olfactory function (OF) was objectified with the Sniffin Sticks test (SST), including threshold (T), discrimination (D) and identification (I) test as well as summarized TDI score, and compared to that in healthy controls. Gustatory function (GF) was evaluated with the suprathreshold taste strips (TS) test, and trigeminal function was tested with an ampoule containing ammonia. RESULTS: Between November 2020 and June 2021, 667 infected individuals (mean age: 48.2 years) were examined 9.1 months, on average, after positive PCR testing. Of these, 45.6% had persisting subjective olfactory dysfunction (OD), 36.2% had subjective gustatory dysfunction (GD). Tested OD, tested GD and impaired trigeminal function were observed in 34.6%, 7.3% and 1.8% of participants, respectively. The mean TDI score of participants was significantly lower compared to healthy subjects. Significant associations were observed between subjective OD and GD, and between tested OD and GD. CONCLUSION: Nine months after SARS-CoV-2 infection, OD prevalence is significantly increased among infected members of the general population. Therefore, OD should be included in the list of symptoms collectively defining Long-COVID.


Subject(s)
COVID-19 , Olfaction Disorders , Adult , Humans , Middle Aged , Cross-Sectional Studies , Olfaction Disorders/epidemiology , Olfaction Disorders/etiology , Olfaction Disorders/diagnosis , SARS-CoV-2 , Post-Acute COVID-19 Syndrome , Smell , Taste Disorders/epidemiology , Taste Disorders/etiology
2.
Animal ; 16(7): 100559, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35709554

ABSTRACT

With the keeping of lactating sows in loose housing systems, ensuring work safety for stockpersons is gaining importance. Aim of the present study was to develop tests characterising the behaviour of lactating sows in farrowing environments with more freedom to move. The behaviour towards humans in different management procedures was examined. Emphasis was given to integrate tests into daily routines. The study was conducted in a nucleus herd with 771 purebred Landrace sows. Data were collected from October 2016 until December 2018. Sows were kept in individual indoor pens with movable farrowing crates in which the animals were restrained from 7 days antepartum (ap) to an average of 7 days postpartum (pp). The Dummy Arm Test (DAT; 1444 observations) was used to assess the sows' reaction towards a stockperson handling the piglets around day 4 pp (closed crates). With the Towel Test (TT; 2846 observations), the reaction of sows to a novel object and an unexpected situation was assessed. The Trough Cleaning Test (TCT; 2805 observations) described the sows' response to common procedures such as trough cleaning. TT and TCT were conducted on days 3 pp (closed crates) and 10 pp (open crates). Variance components of behavioural traits were estimated univariately with a linear animal model, and genetic correlations between traits were derived using a multivariate animal model in ASreml 3.0. Most sows showed no or only a slight reaction to human interactions without attempting to attack them. However, a strong defensive reaction of sows was recorded in 4.0% (TCT), 4.5% (TT), and 10.7% (DAT) of observations. This behaviour of sows was observed more frequently in the open than in the closed pen system. Estimates of heritabilities (h2 ± SE) were h2 = 0.17 ± 0.05 for behaviour of sows towards humans (DAT), h2 = 0.19 ± 0.04 for response of sows towards unexpected situations (TT), and h2 = 0.13 ± 0.04 for reactions of animals to TCT. Genetic correlations (rg ± SE) ranged from rg = 0.59 ± 0.37 between TT and TCT to rg = 0.77 ± 0.30 between TT and DAT. Our results show that the developed tests are suitable for assessing the behaviour of sows towards humans. Behavioural traits derived from these tests could be used as new phenotypes for the genetic selection of gentle and easy-to-handle sows. The genetic correlations of all tests studied were positive indicating related reaction patterns.


Subject(s)
Housing, Animal , Lactation , Animals , Behavior, Animal/physiology , Female , Humans , Lactation/genetics , Maternal Behavior , Postpartum Period , Swine/genetics
3.
Phys Rev Lett ; 124(20): 202502, 2020 May 22.
Article in English | MEDLINE | ID: mdl-32501052

ABSTRACT

Taking benefit of the R3B/SOFIA setup to measure the mass and the nuclear charge of both fission fragments in coincidence with the total prompt-neutron multiplicity, the scission configurations are inferred along the thorium chain, from the asymmetric fission in the heavier isotopes to the symmetric fission in the neutron-deficient thorium. Against all expectations, the symmetric scission in the light thorium isotopes shows a compact configuration, which is in total contrast to what is known in the fission of the heavier thorium isotopes and heavier actinides. This new main symmetric scission mode is characterized by a significant drop in deformation energy of the fission fragments of about 19 MeV, compared to the well-known symmetric scission in the uranium-plutonium region.

4.
Anaesthesist ; 68(7): 444-455, 2019 07.
Article in German | MEDLINE | ID: mdl-31236704

ABSTRACT

BACKGROUND: Jehovah's Witness (JW) patients strictly refuse allogeneic blood transfusion for religious reasons. Nevertheless, JW also wish to benefit from modern therapeutic concepts including major surgical procedures without facing an excessive risk of death. The Northwest Hospital in Frankfurt am Main Germany is a confidential clinic of JW and performs approximately 100 surgical interventions per year on this patient group. MATERIAL AND METHODS: A retrospective analysis of closed medical cases performed in the years 2008-2018 at the Northwest Hospital aimed to clarify (1) the frequency of surgical procedures in JW patients associated with a statistical allogeneic transfusion risk (presence of preoperative anemia and/or in-house transfusion probability >10%) during this time period, (2) the degree of acceptance of strategies avoiding blood transfusion by JW and (3) the anemia-related postoperative mortality rate in JW patients. RESULTS: In the 11- year observation period 123 surgical procedures with a relevant allogeneic transfusion risk were performed in 105 JW patients. Anemia according to World Health Organization (WHO) criteria was present in 44% of cases on the day of surgery. Synthetic and recombinant drugs (tranexamic acid, desmopressin, erythropoetin, rFVIIa) were generally accepted, acute normovolemic hemodilution (ANH) in 92% and cell salvage in 96%. Coagulation factor concentrates extracted from human plasma and therefore generally refused by JW so far, were accepted by 83% of patients following detailed elucidation. Out of 105 JW patients 7 (6.6%) died during the postoperative hospital stay. In 4 of the 7 fatal cases the cause of death could be traced back to severe postoperative anemia. CONCLUSION: Given optimal management JW patients can undergo major surgery without an excessive risk of death. The 6.6% in-hospital mortality observed in this institution was in the range of the 4% generally observed after surgery in Europe. The majority of JW patients accepted a variety of blood conservation strategies following appropriate elucidation. This also included coagulation factor concentrates extracted from human plasma enabling an effective treatment of even severe bleeding complications. In this analysis postoperative hemoglobin concentrations below 6 g/dl in older JW patients were associated with a high mortality risk due to anemia.


Subject(s)
Blood Loss, Surgical/mortality , Blood Loss, Surgical/statistics & numerical data , Jehovah's Witnesses , Surgical Procedures, Operative/mortality , Adult , Aged , Anemia/mortality , Blood Transfusion , Blood Transfusion, Autologous/statistics & numerical data , Bloodless Medical and Surgical Procedures , Female , Germany , Humans , Male , Middle Aged , Preoperative Care , Retrospective Studies
5.
Animal ; 10(7): 1234-42, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26868982

ABSTRACT

The present study examined the possibilities and consequences of selecting pigs for reduced aggression and desirable maternal behaviour. Data were recorded from 798 purebred Large White gilts, with an age of 217±17.7 (mean±SD) days, which were observed at mixing with unfamiliar conspecifics. The reaction of the sows towards separation from their litter was assessed for 2022 litters from 848 Large White sows. Sows' performance during their time in the farrowing unit was scored based on the traits farrowing behaviour (i.e. need of birth assistance), rearing performance (i.e. litter quality at day 10 postpartum (pp)), usability (i.e. additional labour input during lactation period e.g. for treatments) and udder quality of the sow (i.e. udder attachment). For agonistic behaviour, traits heritabilities of h 2=0.11±0.04 to h 2=0.28±0.06 were estimated. For the sow's reaction towards separation from her litter low heritabilities were found (h 2=0.03±0.03 for separation test on day 1 pp and h 2=0.02±0.03 for separation test on day 10 pp). Heritabilities for lactating sow's performance (farrowing behaviour, rearing performance, usability of the sow and udder quality) in the farrowing unit ranged from h 2=0.03±0.02 to h 2=0.19±0.03. Due to these results it can be assumed that selection for these traits, for example, for udder quality or reduced aggression, is possible. Antagonistic associations were found between separation test on day 1 pp and different measures of aggressiveness (r g =-0.22±0.26 aggressive attack and r g =-0.41±0.33 reciprocal fighting). Future studies should determine economic as well as welfare-related values of these traits in order to decide whether selection for these traits will be reasonable.


Subject(s)
Aggression/physiology , Behavior, Animal/physiology , Swine/genetics , Animals , Female , Lactation , Mammary Glands, Animal , Maternal Behavior , Parturition , Phenotype , Postpartum Period , Swine/physiology
6.
Nervenarzt ; 87(7): 746-52, 2016 Jul.
Article in German | MEDLINE | ID: mdl-26628043

ABSTRACT

Violence is a topic of great social relevance, frequently causing tremendous health consequences for those affected and high consequential costs for health care and the national economy. The established consulting and assistance services are usually restricted to offers for ambulant supply, mainly from private agencies or societies. As a result, there is no identification and care for patients who have experienced violence and who are treated in hospital. Another deficiency is the identification and care of male victims of violence. Despite wide-ranging offers of assistance, only very few gender-specific consulting and support services have been available to date.Therefore, the model project "Gender Gewaltkonzept" was initiated at Aachen University Hospital to assess the prevalence of violence and the potential consequences of the violence experienced on the patients' health. In addition, we investigated whether males and females are in need of different supply requirements.Based on the results of the project "Gender Gewaltkonzept" so far, and on prevalence estimates proving that there is a high rate of violent experiences in both males and females, this overview is aimed at presenting the aid and protection concepts available for victims of violence, in addition to the existing deficiencies of the care system. We present approaches to resolving these deficiencies to be able to establish all-encompassing gender-appropriate support for victims of violence.


Subject(s)
Crime Victims/rehabilitation , Crime Victims/statistics & numerical data , Exposure to Violence/statistics & numerical data , Hospitals, University/organization & administration , Models, Organizational , Utilization Review , Adolescent , Adult , Aged , Aged, 80 and over , Female , Germany/epidemiology , Humans , Male , Middle Aged , Prevalence , Risk Factors , Sex Distribution , Young Adult
7.
J Biotechnol ; 232: 69-78, 2016 Aug 20.
Article in English | MEDLINE | ID: mdl-26450562

ABSTRACT

For eukaryotes there seems to be no doubt that differences on the trancriptomic level substantially contribute to the process of species diversification, whereas for bacteria this is thought to be less important. Recent years saw a significant increase in full transcriptome studies for bacteria, which provided deep insight into the architecture of bacterial transcriptomes. Most notably, it became evident that, in contrast to previous scientific consensus, bacterial transcriptomes are quite complex. There exist a large number of cis-antisense RNAs, non-coding RNAs, overlapping transcripts and RNA elements that regulate transcription, such as riboswitches. Furthermore, processing and degradation of RNA has gained interest, because it has a significant impact on the composition of the transcriptome. In this review, we summarize recent findings and put them into a broader context with respect to the complexity of bacterial transcriptomes and its putative biological meanings.


Subject(s)
RNA, Bacterial , Transcriptome , Gene Expression Regulation, Bacterial , RNA, Antisense , RNA, Untranslated , Transcription, Genetic
8.
Phys Med Biol ; 60(21): 8525-47, 2015 Nov 07.
Article in English | MEDLINE | ID: mdl-26485618

ABSTRACT

We present an optimization method to improve the spatial resolution and the water equivalent thickness (WET) accuracy of ion radiographies. The method is designed for imaging systems measuring for each actively scanned beam spot the lateral position of the pencil beam and at the same time the Bragg curve (behind the target) in discrete steps without relying on tracker detectors to determine the ion trajectory before and after the irradiated volume. Specifically, the method was used for an imaging set-up consisting of a stack of 61 parallel-plate ionization chambers (PPIC) interleaved with absorber plates of polymethyl methacrylate (PMMA) working as a range telescope. The method uses not only the Bragg peak position, but approximates the entire measured Bragg curve as a superposition of differently shifted Bragg curves. Their relative weights allow to reconstruct the distribution of thickness around each scan spot of a heterogeneous phantom. The approach also allows merging the ion radiography with the geometric information of a co-registered x-ray radiography in order to increase its spatial resolution. The method was tested using Monte Carlo simulated and experimental proton radiographies of a PMMA step phantom and an anthropomorphic head phantom. For the step phantom, the effective spatial resolution was found to be 6 and 4 times higher than the nominal resolution for the simulated and experimental radiographies, respectively. For the head phantom, a gamma index was calculated to quantify the conformity of the simulated proton radiographies with a digitally reconstructed radiography (DRR) obtained from an x-ray CT and properly converted into WET. For a distance-to-agreement (DTA) of 2.5 mm and a relative WET difference (RWET) of 2.5%, the passing ratio was 100%/85% for the optimized/non-optimized case, respectively. When the optimized proton radiography was merged with the co-registered DRR, the passing ratio was 100% at DTA = 1.3 mm and RWET = 1.3%. A special interpolation method allows to strongly reduce the dose by using a coarser grid of the measured beam spot position with a 5 times larger grid distance. We show that despite a dose reduction of 25 times (leading to a dose of 0.016 mGy for the current imaging set-up), the image quality of the optimized radiographies remains fairly unaffected for both the simulated and experimental case.


Subject(s)
Image Processing, Computer-Assisted/methods , Protons , Tomography, X-Ray Computed/methods
9.
J Mater Chem B ; 3(1): 144-150, 2015 Jan 07.
Article in English | MEDLINE | ID: mdl-32261934

ABSTRACT

We have investigated the kinetics of the uptake and the translocation of nanoparticles in plants. Nearly monodisperse NaYF4:Yb,Er nanocrystals were used, either spherical particles with a diameter of 14 nm or nanorods with a length of 41 nm and a diameter of 22 nm. After watering pumpkin seedlings (Cucurbita maxima) with aqueous colloidal solutions of the particles, intact nanocrystals in the plants were detected in vivo by exciting their upconversion luminescence with a near infrared laser diode (978 nm). The particle concentration in different plant parts was determined by X-ray fluorescence spectroscopy (XRF), making use of the high sensitivity of Yttrium in XRF measurements and its low natural abundance in plants. The results show a fast uptake and translocation of the nanoparticles in all plant organs within three hours. The smaller particles move in the plants faster than the larger ones.

10.
Front Aging Neurosci ; 6: 201, 2014.
Article in English | MEDLINE | ID: mdl-25165448

ABSTRACT

People with mild cognitive impairment (MCI) are at an elevated risk of developing Alzheimer's disease or other forms of dementia. Although the neural correlates of successful memory performance in MCI have been widely investigated, the neural mechanisms involved in unsuccessful memory performance remain unknown. The current study examines the differences between patients suffering from stable amnestic MCI with multiple deficit syndromes and healthy elderly controls in relation to the neural correlates of both successful and unsuccessful encoding and recognition. Forty-six subjects (27 controls, 19 MCI) from the HelMA (Helmholtz Alliance for Mental Health in an Aging Society) completed a comprehensive neuropsychological test battery and participated in an fMRI experiment for associative face-name memory. In patients, the areas of frontal, parietal, and temporal cortices were less involved during unsuccessful encoding and recognition. A temporary dysfunction of the top-down control of frontal or parietal (or both) areas is likely to result in a non-selective propagation of task-related information to memory.

11.
Phys Med Biol ; 59(18): 5501-15, 2014 Sep 21.
Article in English | MEDLINE | ID: mdl-25170567

ABSTRACT

A detector prototype based on a stack of 61 parallel-plate ionisation chambers (PPIC) interleaved with absorber plates of polymethyl methacrylate (PMMA) was assembled for transmission imaging purposes in ion beam therapy. The thickness of the absorber sheets in the PPIC stack determines the nominal range resolution of the detector. In the current set-up, 3 mm PMMA slabs are used. The signal of the 61 active channels of the stack thereby provides a discrete approximation of the Bragg curve in the detector. In this work, a data processing method to increase the range resolution (MIRR) in a stack of ionization chambers is presented. In the MIRR the position of the maximum of the Bragg curve is deduced from the ratio of measured signals in adjacent PPIC channels. The method is developed based on Bragg curves obtained from Monte Carlo simulations and validated with experimental data of a wedge-shaped PMMA phantom acquired with the PPIC stack using carbon ion beams. The influence of the initial beam energy and of phantom inhomogeneities on the MIRR is quantitatively evaluated. Systematic errors as well as inaccuracies related to signal noise are discussed and quantified. It is shown that with the MIRR an increased range resolution of 0.7 mm PMMA equivalent or 0.8 mm water equivalent thickness is achieved for the considered experimental data.


Subject(s)
Algorithms , Proton Therapy/instrumentation , Absorption, Radiation , Polymethyl Methacrylate/chemistry , Proton Therapy/methods , Sensitivity and Specificity
12.
Phys Med Biol ; 59(12): 3041-57, 2014 Jun 21.
Article in English | MEDLINE | ID: mdl-24842455

ABSTRACT

Ion beams offer an excellent tumor-dose conformality due to their inverted depth-dose profile and finite range in tissue, the Bragg peak (BP). However, they introduce sensitivity to range uncertainties. Imaging techniques play an increasingly important role in ion beam therapy to support precise diagnosis and identification of the target volume at the planning stage as well as to ensure the correspondence between the planning and treatment situation at the actual irradiation. For the purpose of improved treatment quality, ion-based radiographic images could be acquired at the treatment site before or during treatment and be employed to monitor the patient positioning and to check the patient-specific ion range. This work presents the initial experimental investigations carried out to address the feasibility of carbon ion radiography at the Heidelberg ion therapy center using a prototype range telescope set-up and an active raster scanning ion beam delivery system. Bragg curves are measured with a stack of ionization chambers (IC) synchronously to the beam delivery. The position of the BP is extracted from the data by locating the channel of maximum current signal for each delivered beam. Each BP is associated to the lateral and vertical positions of the scanned raster point extrapolated from the beam monitor system to build up a radiography. The radiographic images are converted into water equivalent thickness (WET) based on two calibrations of the detector. Radiographies of two phantoms of different complexities are reconstructed and their image quality is analyzed. A novel method proposed to increase the nominal range resolution of the IC stack is applied to the carbon ion radiography of an Alderson head phantom. Moreover, an x-ray digitally reconstructed radiography of the same anthropomorphic head phantom is converted in WET through the clinically used ion range calibration curve and compared with the carbon ion radiography based on a γ-index approach, yielding a good correspondence in terms of absolute WET within ±3%, 3 mm distance-to-agreement and, 87% passing ratio. Imaging artifacts at interfaces within the irradiated phantom due to the finite size of the beam, resulting in multiple maxima, are addressed. Overall, this work demonstrates the feasibility of the prototype range telescope to acquire ion-based transmission imaging with a resolution of up to 0.8 mm WET.


Subject(s)
Carbon , Radiography/instrumentation , Telescopes , Electrical Equipment and Supplies , Feasibility Studies , Head/diagnostic imaging , Humans , Image Processing, Computer-Assisted , Phantoms, Imaging , Polymethyl Methacrylate , Radiometry
13.
Min Eng ; 66(10): 43, 2014 Oct.
Article in English | MEDLINE | ID: mdl-26190862

ABSTRACT

The Office of Mine Safety and Health Research (OMSHR) investigated ways to increase mine airflow to underground metal/nonmetal (M/NM) mine working areas to improve miners' health and safety. One of those areas is controlled recirculation. Because the quantity of mine air often cannot be increased, reusing part of the ventilating air can be an effective alternative, if implemented properly, until the capacity of the present system is improved. The additional airflow can be used to provide effective dilution of contaminants and higher flow velocities in the underground mine environment. Most applications of controlled recirculation involve taking a portion of the return air and passing it back into the intake to increase the air volume delivered to the desired work areas. OMSHR investigated a Nevada gold mine where shaft rehabilitation was in progress and one of the two main fans was shut down to allow reduced air velocity for safe shaft work. Underground booster fan operating pressures were kept constant to maintain airflow to work areas, inducing controlled recirculation in one work zone. Investigation into system behavior and the effects of recirculation on the working area during times of reduced primary ventilation system airflow would provide additional information on implementation of controlled recirculation into the system and how these events affect M/NM ventilation systems. The National Institute for Occupational Safety and Health monitored the ventilation district when both main fans were operating and another scenario with one of the units turned off for maintenance. Airflow and contaminants were measured to determine the exposure effects of induced recirculation on miner health. Surveys showed that 19% controlled recirculation created no change in the overall district airflow distribution and a small reduction in district fresh air intake. Total dust levels increased only modestly and respirable dust levels were also low. Diesel particulate matter (DPM) levels showed a high increase in district intake mass flow, but minor increases in exposure levels related to the recirculation percentage. Utilization of DPM mass flow rates allows input into ventilation modeling programs to better understand and plan for ventilation changes and district recirculation effects on miners' health.

14.
Curr Cardiol Rev ; 9(4): 295-8, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24313645

ABSTRACT

Transcatheter aortic valve implantation (TAVI) is evolving rapidly as a therapeutic option in patients deemed to be at high risk for surgical aortic valve replacement. Early outcome and survival of controlled feasibility trials and single- center experience with TAVI have been previously reported. Valve performance and hemodynamics seem to improve significantly after TAVI. Long-term outcome up to 3 years have been demonstrated in recent studies. Admittedly, the results are encouraging with a survival rate at 2 and 3 years ranging from 62 to 74% and from 56 to 61% respectively. The improvement in hemodynamical and clinical status sustained beyond the 3 years follows up. However, paravalvular leakage after TAVI remains an important issue in this rapidely evolving field.


Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Cardiac Catheterization/methods , Heart Valve Prosthesis Implantation/methods , Heart Valve Prosthesis , Aortic Valve Stenosis/mortality , Cardiac Catheterization/mortality , Heart Valve Prosthesis Implantation/adverse effects , Heart Valve Prosthesis Implantation/mortality , Hemodynamics , Humans , Survival Rate , Treatment Outcome
15.
Curr Cardiol Rev ; 9(4): 268-73, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24313647

ABSTRACT

TAVI (transcatheter aortic valve implantation) is a less invasive treatment of the stenotic aortic valve while avoiding midline sternotomy and cardiopulmonary bypass. A crimped biological valve on a self-expanding or balloonexpandable stent is inserted antegradely or retrogradely under fluoroscopy, and deployed on the beating heart. Among the worldwide TAVI programs, many different concepts have been established for the choice of the access site. Whether retrograde or antegrade TAVI should be considered the superior approach is matter of an ongoing debate. The published literature demonstrates safety of all techniques if performed within a dedicated multidisciplinary team. Since there is no data providing evidence if one approach is superior to another, we conclude that an individualized patient-centered decision making process is most beneficial, taking advantage of the complementarity of the different access options. The aim of this article is to give an overview of the current practice of access techniques for transcatheter based valve treatment and to outline the respective special characteristics.


Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Cardiac Catheterization/methods , Heart Valve Prosthesis Implantation/methods , Aorta , Aortic Valve Stenosis/diagnostic imaging , Femoral Artery , Femoral Vein , Heart Valve Prosthesis , Humans , Jugular Veins , Radiography , Subclavian Artery , Treatment Outcome
16.
Phys Med Biol ; 58(3): 413-27, 2013 Feb 07.
Article in English | MEDLINE | ID: mdl-23296259

ABSTRACT

Ion beams exhibit a finite range and an inverted depth-dose profile, the Bragg peak. These favorable physical properties allow excellent tumor-dose conformality. However, they introduce sensitivity to range uncertainties. Although these uncertainties are typically taken into account in treatment planning, delivery of the intended dose to the patient has to be ensured daily to prevent underdosage of the tumor or overdosage of surrounding critical structures. Thus, imaging techniques play an increasingly important role for treatment planning and in situ monitoring in ion beam therapy. At the Heidelberg Ion Beam Therapy (HIT) center, a prototype detector system based on a stack of 61 ionization chambers has been assembled for the purpose of radiographic and tomographic imaging of transmitted energetic ions. Its applicability to ion-based transmission imaging was investigated experimentally. An extensive characterization of the set-up in terms of beam parameters and settings of the read-out electronics was performed. Overall, the findings of this work support the potential of an efficient experimental set-up as the range telescope equipped with high sensitivity and fast electronics to perform heavy ion radiography and tomography at HIT.


Subject(s)
Carbon/chemistry , Radiography/instrumentation , Tomography/instrumentation , Calibration , Humans , Radiation Dosage
17.
Curr Alzheimer Res ; 10(10): 1098-106, 2013 Dec.
Article in English | MEDLINE | ID: mdl-22746244

ABSTRACT

Mild cognitive impairment (MCI) could be an auspicious candidate for an early marker of a beginning dementia. However, although MCI is accepted as a heterogeneous condition by now, performance testing or diagnosis is often based on a limited number of cognitive tests. Furthermore, there is still disagreement about the necessity to include subjective cognitive complaints as a diagnostic criterion. The current study intends to examine the character of MCI when diagnosis is based upon multiple cognitive domains and does not require the presence of subjective complaints. 130 subjects from the HelMA (Helmholtz Alliance for Mental Health in an Ageing Society) longitudinal study completed a comprehensive neuropsychological test-battery and were diagnosed as either normally-ageing controls or patients with MCI. The prevalence rate of MCI was as high as 46.2%, hereby exceeding most estimates of other studies. Patients with MCI performed worse than controls in each of the 29 administered tests with memory being the predominant impaired cognitive domain. Surprisingly, there was no single patient with a purely non-amnestic impairment, considerably contradicting hitherto existing studies. The rather different distribution of impairment and prevalence rate emphasizes the demand of testbatteries including all cognitive domains so that inferences about MCI are as all-encompassing as possible.


Subject(s)
Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/psychology , Neuropsychological Tests , Aged , Aged, 80 and over , Cognitive Dysfunction/complications , Disease Progression , Female , Humans , Longitudinal Studies , Male , Memory Disorders/diagnosis , Memory Disorders/etiology , Middle Aged , Prevalence , Regression Analysis , Surveys and Questionnaires
18.
Eur J Neurol ; 18(2): 343-346, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20629724

ABSTRACT

BACKGROUND: Progressive carotid artery disease has been shown to cause cerebrovascular events years after a patient's carotid thromboendarterectomy (CEA). Yet, some late cerebrovascular events in CEA patients are attributable to other etiologies. OBJECTIVE: We sought to determine frequency and characteristics of late cerebrovascular events in post-CEA patients attributable to etiologies other than progressive carotid disease. METHODS: In a post hoc analysis of data from a CEA-registry with long-term follow-up, all patients with transient ischaemic attack (TIA) or stroke occurring >1 month post-CEA were identified. The etiologies of these events were dichotomized into the groups large-artery atherosclerosis (LAA) and that non-large-artery atherosclerosis (non-LAA), i.e. all other etiologies (Trial of Org 10172 in Acute Stroke Trial-criteria). Frequency and characteristics of both groups were compared. RESULTS: Sixty of 361 post-CEA patients (16.6%; 95%CI 12.9-20.9%) had late cerebrovascular events after 7 years (median). Thirty patients had ischaemic strokes and 30 had TIAs. These events were attributable to LAA in 48% (29/60) and to non-LAA in 52% (31/60). In the LAA group, contralateral carotid stenosis (62%; 18/29) was more frequent than recurrent ipsilateral stenosis (38%; 11/29). Amongst non-LAA patients, cardioembolism (29%; 9/31) and small-artery-occlusion (23%; 7/31) were the most frequent causes. LAA and non-LAA patients did not differ in age, time since CEA, risk factor profile, type of event, and baseline medication. CONCLUSION: In post-CEA-patients, half of the late cerebrovascular events were attributable to etiologies other than LAA. Clinical features did not distinguish LAA-events from non-LAA events. Thus, stroke prevention in post-CEA patients should not be confined to screening for progressive carotid disease but includes efforts to optimize the management of risk factor and cardiac diseases.


Subject(s)
Endarterectomy, Carotid , Ischemic Attack, Transient/etiology , Postoperative Complications/etiology , Stroke/etiology , Aged , Arterial Occlusive Diseases/complications , Arterial Occlusive Diseases/epidemiology , Atherosclerosis/complications , Carotid Stenosis/complications , Carotid Stenosis/epidemiology , Embolism/complications , Embolism/epidemiology , Endarterectomy, Carotid/adverse effects , Female , Functional Laterality , Humans , Ischemic Attack, Transient/epidemiology , Male , Postoperative Complications/epidemiology , Stroke/epidemiology
19.
Anaesthesist ; 59(4): 297-311, 2010 Apr.
Article in German | MEDLINE | ID: mdl-20379694

ABSTRACT

The religious organization of Jehovah's Witnesses numbers more than 7 million members worldwide, including 165,000 members in Germany. Although Jehovah's Witnesses strictly refuse the transfusion of allogeneic red blood cells, platelets and plasma, Jehovah's Witness patients may nevertheless benefit from modern therapeutic concepts including major surgical procedures without facing an excessive risk of death. The present review describes the perioperative management of surgical Jehovah's Witness patients aiming to prevent fatal anemia and coagulopathy. The cornerstones of this concept are 1) education of the patient about blood conservation techniques generally accepted by Jehovah's Witnesses, 2) preoperative optimization of the cardiopulmonary status and correction of preoperative anemia and coagulopathy, 3) perioperative collection of autologous blood, 4) minimization of perioperative blood loss and 5) utilization of the organism's natural anemia tolerance and its acute accentuation in the case of life-threatening anemia.


Subject(s)
Blood Transfusion , Intraoperative Complications/diagnosis , Jehovah's Witnesses , Perioperative Care/ethics , Treatment Refusal , Anemia/prevention & control , Anemia/therapy , Anesthesia , Blood Coagulation Disorders/prevention & control , Blood Loss, Surgical/prevention & control , Blood Transfusion, Autologous , Blood Volume/physiology , Germany , Hemodilution , Humans , Intraoperative Complications/therapy , Postoperative Complications/blood , Postoperative Complications/therapy , Preoperative Care
20.
New Phytol ; 186(3): 615-22, 2010 May.
Article in English | MEDLINE | ID: mdl-20202127

ABSTRACT

Based on computational prediction of RNA secondary structures, a long antisense RNA (asRNA) was found in chloroplasts of Arabidopsis, Nicotiana tabacum and poplar, which occurs in two to three major transcripts. Mapping of primary 5' ends, northern hybridizations and quantitative real-time reverse transcription polymerase chain reaction (qPCR) experiments demonstrated that these transcripts originate from a promoter that is typical for the plastid-encoded RNA polymerase and are over their full length in antisense orientation to the gene ndhB and therefore were designated asRNA_ndhB. The asRNA_ndhB transcripts predominantly accumulate in young leaves and at physiological growth temperatures. Two nucleotide positions in the mRNA that are subject to C-to-U RNA editing and which were previously found to be sensitive to elevated temperatures are covered by asRNA_ndhB. Nevertheless, the correlation between the accumulation of asRNA_ndhB and RNA editing appeared weak in a temperature shift experiment. With asRNA_ndhB, we describe the first asRNA of plant chloroplasts that covers RNA editing sites, as well as a group II intron splice acceptor site, and that is under developmental control, raising the possibility that long asRNAs could be involved in RNA maturation or the control of RNA stability.


Subject(s)
Arabidopsis/genetics , Chloroplasts/genetics , RNA, Antisense/genetics , RNA, Plant/genetics , Arabidopsis/enzymology , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Base Sequence , Gene Expression Regulation, Plant , Molecular Sequence Data , NADH Dehydrogenase/genetics , NADH Dehydrogenase/metabolism , Populus/genetics , RNA Editing/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Nicotiana/genetics
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