Medizin - Open Access LMU - Teil 20/22 Archiv

Background: Due to the heterogeneous nature of chronic low back pain (CLBP), it is necessary to identify patient groups and evaluate treatments within these groups. We aimed to identify groups of patients with CLBP in the primary care setting. Methods: We performed a k-means cluster analysis on a large data set (n = 634) of primary care patients with CLBP. Variables of sociodemographic data, pain characteristics, psychological status (i.e., depression, anxiety, somatization), and the patient resources of resilience and coping strategies were included. Results: We found three clusters that can be characterized as ``pensioners with age-associated pain caused by degenerative diseases{''

Diagnostically challenging lesions comprise both foci (small lesions) and non-mass-like enhancing lesions and pose a challenge to current computer-aided diagnosis systems. Motion-based artifacts lead in dynamic contrast-enhanced breast magnetic resonance to diagnostic misinterpretation; therefore, motion compensation represents an important prerequisite to automatic lesion detection and diagnosis. In addition, the extraction of pertinent kinetic and morphologic features as lesion descriptors is an equally important task. In the present paper, we evaluate the performance of a computer-aided diagnosis system consisting of motion correction, lesion segmentation, and feature extraction and classification. We develop a new feature extractor, the radial Krawtchouk moment, which guarantees rotation invariance. Many novel feature extraction techniques are proposed and tested in conjunction with lesion detection. Our simulation results have shown that motion compensation combined with Minkowski functionals and Bayesian classifier can improve lesion detection and classification.

Background: Patients diagnosed for a serous ovarian borderline tumor (s-BOT) typically present with an excellent clinical outcome. However there have been controversies concerning the prognostic impact of so-called implants, an extra ovarian spread occurring alongside the s-BOT in certain cases. It remains obscure whether these implants actually resemble metastasis owning the same genetic pattern as the ovarian primary or whether they develop independently. Methods: The current study, in the aim of further clarifying the genetic origin of implants, assessed BRAF/KRAS hot spot mutations and the p53/p16(INK4a) immunophenotype of s-BOTs and corresponding implants (n = 49) of 15 patients by pyro-sequencing and immunostaining, respectively. Results: A significant proportion of both s-BOTs and implants showed KRAS or BRAF mutation and though p16(INK4a) was found to be abundantly expressed, p53 immunoreactivity was rather low. When genotypes of BRAF/KRAS mutated s-BOTs and corresponding implants were compared no patient presented with a fully matching mutation profile of s-BOTs and all corresponding implants. Conclusions: The current study reveals genetic heterogeneity of s-BOTs and implants, as none of the markers examined showed constant reciprocity. Hence, our findings may assist to explain the different clinical presentation of s-BOTs and implants and might encourage to applying more individualized follow up protocols.

Background: The evidence on the long-term economic effects of obesity is still scarce. This study aims to analyse the impact of body mass index (BMI) and BMI-change on future pharmaceutical utilisation and expenditures. Methods: Based on data from 2,946 participants in a German population-based health survey (MONICA/KORA, 1994/95) and the follow-up study (2004/05), drug intake and expenditures were estimated using a bottom-up approach. Using univariate and multivariate methods, we analysed the impact of baseline BMI and BMI-change on drug utilisation and expenditures after 10 years. Results: The use of pharmaceuticals was more likely in moderately and severely obese compared to the normal weight group (OR 1.8 and 4.0, respectively). In those who reported pharmaceutical intake, expenditures were about 40\% higher for the obese groups. A 1-point BMI-gain in 10 years was, on average, associated with almost 6\% higher expenditures compared to a constant BMI. Conclusion: The results suggest that obesity as well as BMI-gain are strong predictors of future drug utilisation and associated expenditures in adults, and thus highlight the necessity of timely and effective intervention and prevention programmes. This study complements the existing literature and provides important information on the relevance of obesity as a health problem.

Background: B cell malignancies are characterized by clonal expansion of B cells expressing tumor-specific idiotypes on their surface. These idiotypes are ideal target antigens for an individualized immunotherapy. However, previous idiotype vaccines mostly lacked efficiency due to a low immunogenicity of the idiotype. The objective of the present study was the determination of the feasibility, safety and immunogenicity of a novel chemically linked phage idiotype vaccine. Methods: In the murine B cell lymphoma 1 model, tumor idiotypes were chemically linked to phage particles used as immunological carriers. For comparison, the idiotype was genetically expressed on the major phage coat protein g8 or linked to keyhole limpet hemocynanin. After intradermal immunizations with idiotype vaccines, tolerability and humoral immune responses were assessed. Results: Feasibility and tolerability of the chemically linked phage idiotype vaccine was demonstrated. Vaccination with B cell lymphoma 1 idiotype expressing phage resulted in a significant survival benefit in the murine B cell lymphoma 1 protection model (60.2 +/- 23.8 days vs. 41.8 +/- 1.6 days and 39.8 +/- 3.8 days after vaccination with wild type phage or phosphate buffered saline, respectively). Superior immunogenicity of the chemically linked phage idiotype vaccine compared to the genetically engineered phage idiotype and keyhole limpet hemocynanin-coupled idiotype vaccine was demonstrated by significantly higher B cell lymphoma 1 idiotype-specific IgG levels after vaccination with chemically linked phage idiotype. Conclusion: We present a novel, simple, time-and cost-efficient phage idiotype vaccination strategy, which represents a safe and feasible therapy and may produce a superior immune response compared to previously employed idiotype vaccination strategies.

Background: The relevance of Trichosporon species for cystic fibrosis (CF) patients has not yet been extensively investigated. Methods: The clinical course of CF patients with Trichosporon spp. in their respiratory secretions was analysed between 2003 and 2010 in the Munich CF center. All respiratory samples of 360 CF patients (0 - 52.4 years; mean FEV1 2010 81.4% pred) were investigated. Results: In 8 patients (2.2%, 3 male, mean age 21.8 years) Trichosporon was detected at least once. One patient carried T. asahii. One patient carried T. mycotoxinivorans and one patient T. inkin as determined by DNA sequencing. As potential risk factors for Trichosporon colonization steroid treatment, allergic bronchopulmonary aspergillosis (ABPA) and CF associated diabetes were identified in 6, 5, and 2 patients respectively. For one patient, the observation period was not long enough to determine the clinical course. One patient had only a single positive specimen and exhibited a stable clinical course determined by change in forced expiratory volume in one second (FEV1), body-mass-index (BMI), C-reactive protein (CRP) and immunoglobulin G (IgG). Of 6 patients with repeatedly positive specimen (mean detection period 4.5 years), 4 patients had a greater decline in FEV1 than expected, 2 of these a decline in BMI and 1 an increase in IgG above the reference range. 2 patients received antimycotic treatment: one patient with a tormenting dry cough subjectively improved under Amphotericin B inhalation; one patient with a severe exacerbation due to T. inkin was treated with i.v. Amphotericin B, oral Voriconazole and Posaconazole which stabilized the clinical condition. Conclusions: This study demonstrates the potential association of Trichosporon spp. with severe exacerbations in CF patients.

Background: In recent years, the prevalence of asthma, rhinoconjunctivitis and eczema symptoms in childhood has considerably increased in developing countries including Bolivia, possibly due to changes in lifestyle, environmental and domestic factors. This study aimed to assess the association between environmental factors and asthma, rhinoconjuctivitis and eczema symptoms in school-aged children from Oropeza Province in Chuquisaca, Bolivia. Methods: A cross-sectional study was performed in 2340 children attending the fifth grade in 36 randomly selected elementary schools in Oropeza province. The prevalence of symptoms was determined using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Environmental factors were assessed by the ISAAC environmental questionnaire including questions related to exposure to pets, farm animals, indoor and outdoor pollution, presence of disease vectors at home and precarious household conditions. Generalized linear mixed-effects models were adjusted for age, sex and place of living. Results: Thirty seven percent of children reported that at least one of their parents smoked at home. Wood or coal was used as cooking fuel in 19\% of the homes and 29\% reported intense truck traffic on the street where they lived. With respect to hygiene conditions, 86\% reported exposure to dogs, 59\% exposure to cats and 36\% regular contact to farm animals. More than one precarious household condition was reported by 8\% of children. In the adjusted model exposure to dog (adjusted OR 1.4; CI 95\% 1.0-1.9), cat (1.2; 1.0-1.5), farm animals (1.5; 1.2-1.8); intense truck traffic (1.3; 1.0-1.6), parents smoking at home (1.2; 1.0-1.5), presence of disease vectors at home (fourth quartile vs. first quartile: 1.6; 1.2-2.3) and two or more precarious household conditions (1.5; 1.0-2.2) were significantly associated with rhinoconjunctivitis symptoms. The associations were similar for asthma and eczema symptoms; however it did not reach the level of statistical significance for all items. Conclusion: Our results support previous findings reported for poor communities especially in Latin America, showing that lower hygiene conditions did not have protective effect against asthma and rhinoconjunctivitis and eczema symptoms.

Background: Elevated plasma preprovasopressin (copeptin) levels are associated with cardiovascular complications as well as with an increased risk for type 2 diabetes (T2D). Here, we studied, whether plasma copeptin is related to carotid intima-media thickness (IMT), a measure of early atherosclerosis, and may thus be one explanation for the high cardiovascular risk in T2D. Methods: Plasma concentrations of copeptin and IMT of the common carotid artery were determined in 1275 participants of the population-based KORA F4 study. We used linear regression models to investigate associations between copeptin levels and IMT. Results: In the whole study group, copeptin levels were not significantly associated with IMT after adjustment for age and sex. Copeptin and IMT were significantly inversely associated after multivariable adjustment in the total cohort (beta = -0.020 mm, 95\% CI: -0.037 mm; -0.003 mm), in men (beta = -0.035 mm, 95\% CI: -0.061 mm; -0.009 mm) and in study participants with prediabetes (beta = -0.041 mm, 95\% CI: -0.078 mm; -0.005 mm) comparing quartile 4 vs quartile 1. The negative association of copeptin and IMT in men was present after adjustment for age alone. In women and patients with T2D, copeptin was not significantly associated with IMT. Conclusions: Plasma copeptin was not associated with an increased IMT in our study cohort. In contrast, copeptin levels were related to a lower IMT in men and subjects with prediabetes, suggesting that elevated copeptin concentrations do not exert proatherogenic effects on carotid arteries.

Background: Adverse drug events are a frequent cause of emergency department presentations. Administrative data could be used to identify patients presenting with adverse drug events for post-market surveillance, and to conduct research in patient safety and in drug safety and effectiveness. However, such data sources have not been evaluated for their completeness with regard to adverse drug event reporting. Our objective was to determine the proportion of adverse drug events to outpatient medications diagnosed at the point-of-care in emergency departments that were documented in administrative data. Methods: We linked the records of patients enrolled in a prospective observational cohort study on adverse drug events conducted in two Canadian tertiary care emergency departments to their administrative data. We compared the number of adverse drug events diagnosed and recorded at the point-of-care in the prospective study with the number of adverse drug events recorded in the administrative data. Results: Among 1574 emergency department visits, 221 were identified as adverse drug event-related in the prospective database. We found 15 adverse drug events documented in administrative records with ICD-10 codes clearly indicating an adverse drug event, indicating a sensitivity of 6.8\% (95\% CI 4.0-11.2\%) of this code set. When the ICD-10 code categories were broadened to include codes indicating a very likely, likely or possible adverse event to a medication, 62 of 221 events were identifiable in administrative data, corresponding to a sensitivity of 28.1\% (95\% CI 22.3-34.6\%). Conclusions: Adverse drug events to outpatient medications were underreported in emergency department administrative data compared to the number of adverse drug events diagnosed and recorded at the point-of-care.

Background: Upside-down stomach (UDS) is characterized by herniation of the entire stomach or most gastric portions into the posterior mediastinum. Symptoms may vary heavily as they are related to reflux and mechanically impaired gastric emptying. UDS is associated with a risk of incarceration and volvulus development which both might be complicated by acute gastric outlet obstruction, advanced ischemia, gastric bleeding and perforation. Case presentation: A 32-year-old male presented with acute intolerant epigastralgia and anterior chest pain associated with acute onset of nausea and vomiting. He reported on a previous surgical intervention due to a hiatal hernia. Chest radiography and computer tomography showed an incarcerated UDS. After immediate esophago-gastroscopy, urgent laparoscopic reduction, repair with a 360 degrees floppy Nissen fundoplication and insertion of a gradually absorbable GORE (R) BIO-A (R)-mesh was performed. Conclusion: Given the high risk of life-threatening complications of an incarcerated UDS as ischemia, gastric perforation or severe bleeding, emergent surgery is indicated. In stable patients with acute presentation of large paraesophageal hernia or UDS exhibiting acute mechanical gastric outlet obstruction, after esophago-gastroscopy laparoscopic reduction and hernia repair followed by an anti-reflux procedure is suggested. However, in cases of unstable patients open repair is the surgical method of choice. Here, we present an exceptionally challenging case of a young patient with a giant recurrent hiatal hernia becoming clinically manifest in an incarcerated UDS.

Background: The capacity of patient's Natural Killer cells (NKs) to be activated for cytolysis is an important prerequisite for the success of antibody-derived agents such as single-chain triplebodies (triplebodies) in cancer therapy. NKs recovered from AML patients at diagnosis are often found to be reduced in peripheral blood titers and cytolytic activity. Here, we had the unique opportunity to compare blood titers and cytolytic function of NKs from an AML patient with those of a healthy monozygotic twin. The sibling's NKs were compared with the patient's drawn either at diagnosis or in remission after chemotherapy. The cytolytic activities of NKs from these different sources for the patient's autologous AML blasts and other leukemic target cells in conjunction with triplebody SPM-2, targeting the surface antigens CD33 and CD123 on the AML cells, were compared. Methods: Patient NKs drawn at diagnosis were compared to NKs drawn in remission after chemotherapy and a sibling's NKs, all prepared from PBMCs by immunomagnetic beads (MACS). Redirected lysis (RDL) assays using SPM-2 and antibody-dependent cellular cytotoxicity (ADCC) assays using the therapeutic antibody Rituximab (TM) were performed with the enriched NKs. In addition, MACS-sorted NKs were analyzed for NK cell activating receptors (NCRs) by flow cytometry, and the release of TNF-alpha and IFN-gamma from blood samples of both siblings after the addition of the triplebody were measured in ELISA-assays. Results: Patient NKs isolated from peripheral blood drawn in remission produced comparable lysis as NKs from the healthy twin against the patient's autologous bone marrow (BM) blasts, mediated by SPM-2. The NCR receptor expression profiles on NKs from patient and twin were similar, but NK cell titers in peripheral blood were lower for samples drawn at diagnosis than in remission. Conclusions: Peripheral blood NK titers and ex vivo cytolytic activities mediated by triplebody SPM-2 were comparable for cells drawn from an AML patient in remission and a healthy twin. If these results can be generalized, then NKs from AML patients in remission are sufficient in numbers and cytolytic activity to make triplebodies promising new agents for the treatment of AML.

Background: Loss of meniscal tissue is correlated with early osteoarthritis but few data exist regarding detailed biomechanical properties (e. g. viscoelastic behavior) of menisci in different species commonly used as animal models. The purpose of the current study was to biomechanically characterize bovine, ovine, and porcine menisci (each n = 6, midpart of the medial meniscus) and compare their properties to that of normal and degenerated human menisci (n = 6) and two commercially available artificial scaffolds (each n = 3). Methods: Samples were tested in a cyclic, minimally constraint compression-relaxation test with a universal testing machine allowing the characterization of the viscoelastic properties including stiffness, residual force and relative sample compression. T-tests were used to compare the biomechanical parameters of all samples. Significance level was set at p < 0.05. Results: Throughout cyclic testing stiffness, residual force and relative sample compression increased significantly (p < 0.05) in all tested meniscus samples. From the tested animal meniscus samples the ovine menisci showed the highest biomechanical similarity to human menisci in terms of stiffness (human: 8.54 N/mm +/- 1.87, cycle 1; ovine: 11.24 N/mm +/- 2.36, cycle 1, p = 0.0528), residual force (human: 2.99 N +/- 0.63, cycle 1 vs. ovine 3.24 N +/- 0.13, cycle 1, p = 0.364) and relative sample compression (human 19.92\% +/- 0.63, cycle 1 vs. 18.72\% +/- 1.84 in ovine samples at cycle 1, p = 0.162). The artificial constructs - as hypothesized- revealed statistically significant inferior biomechanical properties. Conclusions: For future research the use of ovine meniscus would be desirable showing the highest biomechanical similarities to human meniscus tissue. The significantly different biomechanical properties of the artificial scaffolds highlight the necessity of cellular ingrowth and formation of extracellular matrix to gain viscoelastic properties. As a consequence, a period of unloading (at least partial weight bearing) is necessary, until the remodeling process in the scaffold is sufficient to withstand forces during weight bearing.

Background: For future eradication strategies of malaria it is important to control the transmission of gametocytes from humans to the anopheline vector which causes the spread of the disease. Sensitive, non-invasive methods to detect gametocytes under field conditions can play a role in monitoring transmission potential. Methods: Microscopically Plasmodium falciparum-positive patients from Jimma, Ethiopia donated finger-prick blood, venous blood, saliva, oral mucosa and urine samples that were spotted on filter paper or swabs. All samples were taken and stored under equal, standardized conditions. RNA was extracted from the filter paper and detected by real-time QT-NASBA. Pfs16-mRNA and Pfs25-mRNA were measured with a time to positivity to detect gametocyte specific mRNA in different gametocyte stages. They were compared to 18S-rRNA, which is expressed in all parasite stages. Results were quantified via a known dilution series of artificial RNA copies. Results: Ninety-six samples of 16 uncomplicated malaria patients were investigated. 10 (66.7%) of the slides showed gametocyte densities between 0.3-2.9 gametocytes/mu l. For all RNA-targets, molecular detection in blood samples was most sensitive; finger-prick sampling required significantly smaller amounts of blood than venous blood collection. Detection of asexual 18S-rRNA in saliva and urine showed sensitivities of 80 and 67%, respectively. Non-invasive methods to count gametocytes proved insensitive. Pfs16-mRNA was detectable in 20% of urine samples, sensitivities for other materials were lower. Pfs25-mRNA was not detectable in any sample. Conclusions: The sensitivity of non-invasively collected material such as urine, saliva or mucosa seems unsuitable for the detection of gametocyte-specific mRNA. Sensitivity in asymptomatic carriers might be generally even lower. Finger-prick testing revealed the highest absolute count of RNA copies per mu L, especially for Pfs25-mRNA copies. The method proved to be the most effective and should preferably be applied in future transmission control and eradication plans. A rapid test for gametocyte targets would simplify efforts.

Background: Ralstonia solanacearum is a soil-borne beta-proteobacterium that causes bacterial wilt disease in many food crops and is a major problem for agriculture in intertropical regions. R. solanacearum is a heterogeneous species, both phenotypically and genetically, and is considered as a species complex. Pathogenicity of R. solanacearum relies on the Type III secretion system that injects Type III effector (T3E) proteins into plant cells. T3E collectively perturb host cell processes and modulate plant immunity to enable bacterial infection. Results: We provide the catalogue of T3E in the R. solanacearum species complex, as well as candidates in newly sequenced strains. 94 T3E orthologous groups were defined on phylogenetic bases and ordered using a uniform nomenclature. This curated T3E catalog is available on a public website and a bioinformatic pipeline has been designed to rapidly predict T3E genes in newly sequenced strains. Systematical analyses were performed to detect lateral T3E gene transfer events and identify T3E genes under positive selection. Our analyses also pinpoint the RipF translocon proteins as major discriminating determinants among the phylogenetic lineages. Conclusions: Establishment of T3E repertoires in strains representatives of the R. solanacearum biodiversity allowed determining a set of 22 T3E present in all the strains but provided no clues on host specificity determinants. The definition of a standardized nomenclature and the optimization of predictive tools will pave the way to understanding how variation of these repertoires is correlated to the diversification of this species complex and how they contribute to the different strain pathotypes.