-
[show abstract]
[hide abstract]
ABSTRACT: BACKGROUND: Almost nothing is known about the medical aspects of runners doing a transcontinental ultramarathon over several weeks. The results of differentiated measurements of changes in body composition during the Transeurope Footrace 2009 using a mobile whole body magnetic resonance (MR) imager are presented and the proposed influence of visceral and somatic adipose and lean tissue distribution on performance tested. METHODS: 22 participants were randomly selected for the repeated MR measurements (intervals: 800 km) with a 1.5 Tesla MR scanner mounted on a mobile unit during the 64-stage 4,486 km ultramarathon. A standardized and validated MRI protocol was used: T1 weighted turbo spin echo sequence, echo time 12 ms, repetition time 490 ms, slice thickness 10mm, slice distance 10mm (breath holding examinations). For topographic tissue segmentation and mapping a modified fuzzy c-means algorithm was used. A semi-automatic post-processing of whole body MRI data sets allows reliable analysis of the following body tissue compartments: Total body volume (TV), total somatic (TSV) and total visceral volume (TVV), total adipose (TAT) and total lean tissue (TLT), somatic (SLT) and visceral lean tissue (VLT), somatic (SAT) and visceral adipose tissue (VAT) and somatic adipose soft tissue (SAST). Specific volume changes were tested on significance. Tests on difference and relationship regarding prerace and race performance and non-finishing were done using statistical software SPSS. RESULTS: Total, somatic and visceral volumes showed a significant decrease throughout the race. Adipose tissue showed a significant decrease compared to the start at all measurement times for TAT, SAST and VAT. Lean adipose tissues decreased until the end of the race, but not significantly. The mean relative volume changes of the different tissue compartments at the last measurement compared to the start were: TV -9.5% (SE 1.5%), TSV -9.4% (SE 1.5%), TVV -10.0% (SE 1.4%), TAT -41.3% (SE 2.3%), SAST -48.7% (SE 2.8%), VAT -64.5% (SE 4.6%), intraabdominal adipose tissue (IAAT) -67.3% (SE 4.3%), mediastinal adopose tissue (MAT) -41.5% (SE 7.1%), TLT -1.2% (SE 1.0%), SLT -1.4% (SE 1.1%). Before the start and during the early phase of the Transeurope Footrace 2009, the non-finisher group had a significantly higher percentage volume of TVV, TAT, SAST and VAT compared to the finisher group. VAT correlates significantly with prerace training volume and intensity one year before the race and with 50 km- and 24 hour-race records. Neither prerace body composition nor specific tissue compartment volume changes showed a significant relationship to performance in the last two thirds of the Transeurope Footrace 2009. CONCLUSIONS: With this mobile MRI field study the complex changes in body composition during a multistage ultramarathon could be demonstrated in detail in a new and differentiated way. Participants lost more than half of their adipose tissue. Even lean tissue volume (mainly skeletal muscle tissue) decreased due to the unpreventable chronic negative energy balance during the race. VAT has the fastest and highest decrease compared to SAST and lean tissue compartments during the race. It seems to be the most sensitive morphometric parameter regarding the risk of non-finishing a transcontinental footrace and shows a direct relationship to prerace-performance. However, body volume or body mass and, therefore, fat volume has no correlation with total race performances of ultra-athletes finishing a 4,500 km multistage race.
BMC Medicine 05/2013; 11(1):122. · 6.03 Impact Factor
-
Uwe H W Schütz,
Arno Schmidt-Trucksäss,
Beat Knechtle,
Jürgen Machann,
Heike Wiedelbach,
Martin Ehrhardt,
Wolfgang Freund,
Stefan Gröninger,
Horst Brunner,
Ingo Schulze,
Hans-Jürgen Brambs, Christian Billich
[show abstract]
[hide abstract]
ABSTRACT: The TransEurope FootRace 2009 (TEFR09) was one of the longest transcontinental ultramarathons with an extreme endurance physical load of running nearly 4,500 km in 64 days. The aim of this study was to assess the wide spectrum of adaptive responses in humans regarding the different tissues, organs and functional systems being exposed to such chronic physical endurance load with limited time for regeneration and resulting negative energy balance. A detailed description of the TEFR project and its implemented measuring methods in relation to the hypotheses are presented.
The most important research tool was a 1.5 Tesla magnetic resonance imaging (MRI) scanner mounted on a mobile unit following the ultra runners from stage to stage each day. Forty-four study volunteers (67% of the participants) were cluster randomized into two groups for MRI measurements (22 subjects each) according to the project protocol with its different research modules: musculoskeletal system, brain and pain perception, cardiovascular system, body composition, and oxidative stress and inflammation. Complementary to the diverse daily mobile MR-measurements on different topics (muscle and joint MRI, T2*-mapping of cartilage, MR-spectroscopy of muscles, functional MRI of the brain, cardiac and vascular cine MRI, whole body MRI) other methods were also used: ice-water pain test, psychometric questionnaires, bioelectrical impedance analysis (BIA), skinfold thickness and limb circumference measurements, daily urine samples, periodic blood samples and electrocardiograms (ECG).
Thirty volunteers (68%) reached the finish line at North Cape. The mean total race speed was 8.35 km/hour. Finishers invested 552 hours in total. The completion rate for planned MRI investigations was more than 95%: 741 MR-examinations with 2,637 MRI sequences (more than 200,000 picture data), 5,720 urine samples, 244 blood samples, 205 ECG, 1,018 BIA, 539 anthropological measurements and 150 psychological questionnaires.
This study demonstrates the feasibility of conducting a trial based centrally on mobile MR-measurements which were performed during ten weeks while crossing an entire continent. This article is the reference for contemporary result reports on the different scientific topics of the TEFR project, which may reveal additional new knowledge on the physiological and pathological processes of the functional systems on the organ, cellular and sub-cellular level at the limits of stress and strain of the human body. Please see related articles: http://www.biomedcentral.com/1741-7015/10/76 and http://www.biomedcentral.com/1741-7015/10/77.
BMC Medicine 07/2012; 10:78. · 6.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Systematic aerobe training has positive effects on the compliance of dedicated arterial walls. The adaptations of the arterial structure and function are associated with the blood flow-induced changes of the wall shear stress which induced vascular remodelling via nitric oxide delivered from the endothelial cell. In order to assess functional changes of the common carotid artery over time in these processes, a precise measurement technique is necessary. Before this study, a reliable, precise, and quick method to perform this work is not present.
We propose a fully automated algorithm to analyze the cross-sectional area of the carotid artery in MR image sequences. It contains two phases: (1) position detection of the carotid artery, (2) accurate boundary identification of the carotid artery. In the first phase, we use intensity, area size and shape as features to discriminate the carotid artery from other tissues and vessels. In the second phase, the directional gradient, Hough transform, and circle model guided dynamic programming are used to identify the boundary accurately.
We test the system stability using contrast degraded images (contrast resolutions range from 50% to 90%). The unsigned error ranges from 2.86% ± 2.24% to 3.03% ± 2.40%. The test of noise degraded images (SNRs range from 16 to 20 dB) shows the unsigned error ranging from 2.63% ± 2.06% to 3.12% ± 2.11%. The test of raw images has an unsigned error 2.56% ± 2.10% compared to the manual tracings.
We have proposed an automated system which is able to detect carotid artery cross sectional boundary in MRI sequences during heart cycles. The accuracy reaches 2.56% ± 2.10% compared to the manual tracings. The system is stable, reliable and results are reproducible.
BioMedical Engineering OnLine 01/2011; 10:26. · 1.40 Impact Factor
-
Forschung 01/2010; 35(2):4-9.
-
[show abstract]
[hide abstract]
ABSTRACT: This study was conducted to evaluate whether instillation of NaCl 0.9% solution into the biopsy track reduces the incidence of pneumothoraces after CT-guided lung biopsy. A total of 140 consecutive patients with pulmonary lesions were included in this prospective study. All patients were alternatingly assigned to one of two groups: group A in whom the puncture access was sealed by instillation of NaCl 0.9% solution during extraction of the guide needle (n = 70) or group B for whom no sealing was performed (n = 70). CT-guided biopsy was performed with a 18-G coaxial system. Localization of lesion (pleural, peripheral, central), lesion size, needle-pleural angle, rate of pneumothorax and alveolar hemorrhage were evaluated. In group A, the incidence of pneumothorax was lower compared to group B (8%, 6/70 patients vs. 34%, 24/70 patients; P < 0.001). All pneumothoraces occurred directly post punctionem after extraction of the guide needle. One patient in group A and eight patients in group B developed large pneumothoraces requiring chest tube placement (P = 0.01). The frequency of pneumothorax was independent of other variables. After CT-guided biopsy, instillation of NaCl 0.9% solution into the puncture access during extraction of the needle significantly reduces the incidence of pneumothorax.
European Radiology 06/2008; 18(6):1146-52. · 3.22 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Borna disease virus (BDV) can infect many vertebrate species, including humans. BDV infection may lead to meningoencephalomyelitis in animals. An association with human neuropsychiatric diseases has been reported, but the causal relationship between BDV and human disease remains unclear.
To find out whether BDV is present in Finland and to look for a potential reservoir, we examined a large panel of blood samples from different vertebrate species with immunofluorescence assay. Samples from horses, cats, dogs, sheep, cattle, large predators, grouse, wild rodents and humans were included. Most positive results were confirmed by other specific methods and in other laboratories.
BDV-specific antibodies were detected in 10 horses, 2 cats, as well as 2 horses and 1 dog from farms housing a previously detected seropositive horse. Interestingly, BDV-specific antibodies were further detected in three wild rodents. In humans, BDV-specific antibodies were detected in a veterinarian and in two patients suspected to have a Puumala hantavirus infection. Our serological analysis suggests that BDV infects various vertebrates in Finland, including humans. Furthermore, our data indicate for the first time that BDV infects also wild rodents.
Journal of Clinical Virology 02/2007; 38(1):64-9. · 3.97 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Borna Disease Virus (BDV) is suspected to infect humans and to be associated with psychiatric disorders. To this date, BDV-reactive antibodies provide the only reliable markers to diagnose human BDV infection. Their diagnostic value, however, was recently questioned by the observation that these antibodies recognize BDV antigen with only low avidity, a typical feature of cross-reacting antibodies. This raised the possibility that the human BDV-reactive antibodies were triggered by other pathogens than BDV. The recent establishment of a peptide array-based screening test allowed the further characterization of these antibodies. It revealed the presence of small amounts of BDV-reactive antibodies in crude human sera that specifically recognized various epitopes of three major BDV proteins. Most importantly, the purified epitope-specific antibodies were shown to bind to BDV antigen with high avidity when assayed by conventional immunofluorescence assay (IFA) or by Western blot. These results are compatible with the view that the presence of BDV-reactive antibodies in human sera reflects an infection with BDV, although the poor affinity maturation remains unexplained. Furthermore, it demonstrates that peptide array-based screening tests are a reliable system for identifying monospecific antibodies from human polyclonal sera with high specificity and sensitivity.
Molecular Diversity 02/2004; 8(3):247-50. · 3.15 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The recent observation that Borna disease virus (BDV)-reactive antibodies from psychiatric patients exhibit only low avidity for BDV antigen called into question their diagnostic value and raised the possibility that antigenically related microorganisms or self antigens caused the production of these antibodies. We further characterized the specificity of these antibodies.
We established a peptide array-based screening test that allows the identification of antibodies directed against linear epitopes of the two major BDV proteins, the nucleoprotein (N) and the phosphoprotein (P).
Initial tests employing sera of BDV-infected mice and rats or horses with Borna disease revealed a high specificity and sensitivity of this test. All sera recognized epitopes of N, P, or both. Sera of noninfected rats, mice, and horses showed no signals on either peptide array. Several human sera that recognized BDV antigen by indirect immunofluorescence contained antibodies that recognized various linear epitopes of one or even both BDV proteins. Remarkably, antibodies purified from such human serum by matrix-immobilized peptides showed high-avidity binding to BDV antigens when assayed by IFA or Western blotting.
These data suggest that reactive antibodies found in psychiatric patients indeed indicate infection with BDV or a BDV-like agent. However, the poor affinity maturation of BDV-specific human antibodies remains unexplained.
Biological Psychiatry 07/2002; 51(12):979-87. · 8.28 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study involved 92 patients with clinically diagnosed pneumonia. Differences in the frequency of typical pattern were calculated for patients with mild pneumonia and for patients with severe pneumonia (confusion, respiratory rate, blood pressure, 65 years of age and older). The frequency of singular morphologic changes did not differ significantly between the two groups. Empyema and pleural effusion, as well as an atelectasis in combination with patchy infiltrates and a positive bronchogram/multisegmental infiltrates, seem to have an influence on severity of pneumonia.
Clinical imaging 32(5):342-5. · 0.73 Impact Factor
-
Christian Billich
[show abstract]
[hide abstract]
ABSTRACT: Das Borna Disease Virus (BDV) ist ein neurotropes nichtsegmentiertes Negativstrang-RNA-Virus. Eine natürliche Infektion mit dem BDV kann vor allem bei Pferden und Schafen zu einer immunvermittelten Erkrankung des zentralen Nervensystems führen. Die Bornasche Erkrankung (BD) äußert sich klinisch unter anderem in schweren Bewegungs- und Verhaltensstörungen und endet meist mit dem Tod der Tiere. Zu beobachtende Analogien zwischen BDV-induzierten Verhaltensstörungen in Tiermodellen und humanen psychiatrischen Erkrankungen, sowie das breite Wirtsspektrum des BDV, veranlaßten Rott und Mitarbeiter Mitte der 80iger Jahre, erstmals eine seroepidemiologische Studie mit humanen Seren durchzuführen. In dieser Studie konnte gezeigt werden, daß man im Blut psychiatrischer Patienten im Vergleich zu Kontrollgruppen Gesunder häufiger BDV-spezifische IgG nachweisen kann (Rott et al., 1985). Dieses Ergebnis führte zu der Annahme, daß eine BDV-Infektion mit bestimmten humanen psychiatrischen Erkrankungen wie Schizophrenie oder affektiven Störungen assoziiert sein könnte. Der diagnostische Wert von BDV-reaktiven humanen Antikörpern wurde jedoch von Allmang und Mitarbeitern in Frage gestellt, nachdem sie zeigen konnten, daß humane BDV-reaktive Antikörper - im Gegensatz zu BDV-reaktiven Antikörpern aus Tierseren - mit niedrigerer Avidität an BDV-Antigene binden. Sie vermuteten, daß diese niedrigaviden Antikörper möglicherweise nicht durch eine transiente oder persistente Infektion mit dem BDV sondern durch Infektion mit einem bisher unbekannten Mikroorganismus induziert wurden (Allmang et al., 2001). In der vorliegenden Arbeit gelang es erstmals mit Hilfe von speziell synthetisierten Peptidarrays, welche die BDV-Proteine N, P und M repräsentieren, die Spezifität BDV-reaktiver Antikörper weiter zu charakterisieren. So konnte gezeigt werden, daß die BDV-reaktiven Antikörper in den untersuchten Humanseren ein komplexes Muster an BDV-spezifischen linearen Epitopen auf den Peptidarrays erkennen. Desweiteren konnten mittels Peptidreinigung auch in Humanseren hochavide BDV-reaktive Antikörper angereichert und somit nachgewiesen werden. Diese Ergebnisse deuten darauf hin, daß die BDV-reaktiven Antikörper in den untersuchten Humanseren eventuell doch durch Kontakt mit BDV oder einem ihm eng verwandten Virus generiert wurden. Jedoch muß betont werden, daß der Nachweis BDV-spezifischer Antikörper kein Beweis für die humane Pathogenität des BDV ist. Borna disease virus (BDV) is a negative-stranded RNA virus (Briese et al 1992, 1994; Cubitt et al 1994) that naturally infects a broad range of warm-blooded animals, predominantly horses and sheep, and can induce a fatal neurologic disorder termed Borna disease (Jordan and Lipkin 2001; Ludwig and Bode 1997; Richt and Rott 2001; Staeheli et al 2000). Affected animals typically present with neurologic dysfunction including behavioral abnormalities (Carbone et al 2001; Hornig et al 2001). Seroepidemiologic surveys by immunofluorescence (IFA) using BDV-infected cell cultures have suggested that humans also can be infected with BDV and that these infections are associated with mental disorders (Carbone 2001; Ludwig and Bode 2000; Rott et al 1985; Schwemmle 2001). The detection of viral RNA by nested Reverse Transcription and Polymerase Chain Reaction RT-PCR) in blood and brain samples of psychiatric patients initially appeared to corroborate this suspicion further (Bode et al 1995; Carbone 2001; Ludwig and Bode 2000; Staeheli et al 2000); however, with the number of subsequent similar studies increasing, a highly controversial debate arose regarding whether BDV is infecting humans at all (Carbone 2001; Ludwig and Bode 2000; Schwemmle 2001; Staeheli et al 2000). Some laboratories failed to detect viral nucleic acid in human blood and brain samples despite high sensitivity of the nested RT-PCR assay, whereas others identified up to 66% of their patient cohorts to be BDV-positive with this test. A more uniform picture emerged from numerous serological studies that when employing various serological test assays, consistently found a higher frequency of seropositives among psychiatric patients than in healthy control subjects, supporting the suspicion that BDV might indeed be responsible for some psychiatric disorders (Schwemmle 2001). Most recently, however, the diagnostic value of these antibodies was questioned by the observation that they fail to bind BDV antigen with high avidity (Allmang et al 2001). Because cross-reacting antibodies typically exhibit low-avidity phenotype (Lehtonen and Meuman 1986; Schupbach et al 1988), it was speculated that other microbial infections or unknown self-antigens might havecaused this immunologic response (Allmang et al 2001). Using peptide arrays representing BDV nucleoprotein (BDV-N) and BDV phosphoprotein (BDV-P), we have further characterized the specificity of these BDV-reactive antibodies. Experiments with monoclonal antibodies and sera of BDV-infected mice and rats or naturally infected horses revealed a high specificity of this screening method. We show here that many BDV-reactive human sera contained antibodies that recognized several linear epitopes of the two major BDV proteins. Intriguingly, antibodies purified from crude reactive human serum by matrix-immobilized peptides showed high-avidity binding to BDV antigens. These findings are compatible with the view that the antibodies in question were generated in response to exposure to BDV or a closely related virus.
-
Christian. Billich
[show abstract]
[hide abstract]
ABSTRACT: Enth. ausserdem 1 Sonderabdr. aus: Biological psychiatry ; Bd. 51. 2002. - Beitr. teilw. dt., teilw. engl. Freiburg (Breisgau), Univ., Diss., 2004 (Nicht für den Austausch).
