The impact of shore types on benthic macroinvertebrate community structure and functioning in a large lowland river

Shore zones of large rivers are hot spots of biodiversity and contribute significantly to riverine ecosystem functioning. Today, shore degradation and other structural impair-ments like river straightening and channelization are strong impact factors on river ecosystem health. However, we still lack a thorough understanding of how structural shore zone degradation affects benthic community composition and their inherent ecosystem functions. In this thesis I tested the influence of training structure induced environmental factors on benthic macroinvertebrate community composition and the share of non-native species. Moreover, I assessed the community-associated ecosystem functions in terms of secondary production and resource utilization. In the main channel, communities were composed of only a few specialized taxa with low abundances, which contributed little to riverine secondary production. This is probably due to the harsh conditions produced by constantly high flow velocities and relocation of the fine sandy sediment. Main channel habitats were hardly affected by the adjacent training structure. Hence, species compositions and productivities were similar at all investigated main channel sites. By contrast, each of the shore communities was diverse, highly abundant and productive in comparison to the main channel. However, variations between shore structure communities and their ecosystem functions were prominent. One particular training structure, i.e. the off-bankline revetment, bore the most diverse and by far most productive benthic community, which utilized vast total amounts of basal resources (1,323 g DM m-² y-1). Varying sediment compositions, availability of macrophytes and diverse flow velocities, including lentic conditions, were revealed as key factors for increasing biodiversity, secondary production and resource utilization. Allochthonous boulder habitats were generally highly prone to non-native species invasion. Neozoa proved less productive than many native community members and consumed minor relative and total amounts of the prevailing resource pelagic algae. The present quantitative comparison of shore type specific effects on biodiversity, biomass and productivity provides managers with a tool to improve the ecological attributes of large river ecosystems with an unchangeable, impaired macrostructure. In its entirety, this thesis constitutes a sound basis to increase the mechanistic understanding of the way in which shore zone manipulation can affect riverine benthic communities and their associated ecosystem functions.Die Uferbereiche großer Flüsse sind für die Biodiversität und Funktion dieser Ökosys-teme von enormer Bedeutung. Uferdegradierung und Kanalisierung gehören zu wichti-gen Faktoren, die Flussökosysteme nachhaltig beeinträchtigen. Wie sich anthropogene Umstrukturierungen der Uferbereiche auf die Zusammensetzung benthischer Ge-meinschaften und deren Ökosystemfunktion auswirken ist jedoch weitestgehend unbe-kannt. In dieser Arbeit werden die Effekte von uferspezifischen Habitatfaktoren auf die Komposition des Makrozoobenthos und den Anteil an Neozoen getestet. Zudem wurden die gemeinschaftsassoziierten Ökosystemfunktionen in Bezug auf Sekundärproduktion und Ressourcennutzung erfasst und bewertet. Die benthische Gemeinschaft des Hauptstroms bestand lediglich aus wenigen spezialisierten Arten, welche nur geringfügig zur Gesamtsekundärproduktion des Flusses beitrugen. Dies war vermutlich auf die rauen Bedingungen im Hauptstrom (insbesondere hohe Strömungsgeschwindigkeiten und damit verbundener Sedimenttransport) zurückzuführen. Die Makrozoobenthosgemeinschaften des Hauptroms wurden von den jeweils angrenzenden Ufertypen nicht beeinflusst. Im Gegensatz zum Hauptstrom zeigte jeder der untersuchten Ufertypen hohe Dichten an benthischen Invertebraten wobei sich Zusammensetzung und Funktion der Artengemeinschaften zwischen den Ufertypen stark unterschieden. Dabei brachte das Parallelwerk die diverseste und produktivste Makroinvertebratenfauna hervor, welche enorme Mengen basaler Ressourcen ingestierte (1,323 g DM m-2y-1). Hauptfaktoren für eine Erhöhung von Biodiversität, Sekundärproduktion und Ressourcennutzung waren neben variablen Sedimentzusammensetzungen und Makrophytenbeständen sich oft ändernde Fließgeschwindigkeiten mit lentischen Phasen. Allochthone Steinhabitate waren generell anfällig für die Invasion nicht heimischer Arten. Diese Neozoen waren weniger produktiv als viele heimische Taxa und nutzten nur geringe Mengen pelagischer Algen, welche die meist verfügbare Ressource darstellten. Aus dem ökologischen Vergleich der verschiedenen Ufertypen lassen sich Managementempfehlungen zur Verbesserung des ökologischen Zustandes in Bezug auf Biodiversität und Ökosystemfunktionen ableiten, welche für große Flüsse mit degradierter und unveränderbarer Makrostruktur in Betracht gezogen werden können. In ihrer Gesamtheit liefert diese Arbeit ein fundiertes mechanistisches Verständnis über die Effekte von Ufermanipulationen auf benthische Gemeinschaften und deren assoziierte Ökosystemfunktionen in großen Flüssen

Evaluation of quality indicators following implementation of total mesorectal excision in primarily resected rectal cancer changed future management

Background and aims: We evaluated the outcome of primarily resected rectal cancer patients immediately after the implementation of total meserectal excision (TME) based on potential quality indicators. Patients and methods: Following initial teaching of two staff surgeons (PMS and AHH) by RJ Heald, 164 consecutive patients were analyzed. The following quality indicators were evaluated: (a) frequency of local recurrence, (b) number of resected lymph nodes, (c) selection of operative technique depending on tumor localization, (d) use of a protective loop ileostomy, and (e) frequency and type of adjuvant therapy. Results: Local recurrence rate was 8.5% after a minimum follow-up of 5years. An increasing pT category (p < 0.02) and the presence of lymph node metastases (pN+, p < 0.05) were significantly associated with local recurrence rates. The number of resected lymph nodes was significantly associated with nodal metastases rate (p < 0.02). Patients with distal third rectal cancer underwent significantly more often an abdominoperineal amputation (p < 0.0001). Clinical course, but not the rate of anastomotic leakage (9.5%) itself was influenced by using a protective loop ileostomy. Forty-two (29.7%) patients received adjuvant therapy; however, local recurrence rate was higher in patients with adjuvant chemo-/radiotherapy (14.2% vs. 6.1%). Conclusions: The local recurrence rate of 8.5% demonstrates that through consequent implementation of TME excellent onclogical results can be achieved. The number of resected lymph nodes significantly influenced the pN category. The primary construction of a protective loop ileostomy after TME became standard. Neoadjuvant chemoradiation was systematically introduced in order to improve local tumor control and prevent abdominoperineal amputations. No conclusions can be drawn concerning adjuvant therap

Joint co-clustering: co-clustering of genomic and clinical bioimaging data

AbstractFor better understanding the genetic mechanisms underlying clinical observations, and better defining a group of potential candidates for protein-family-inhibiting therapy, it is interesting to determine the correlations between genomic, clinical data and data coming from high resolution and fluorescent microscopy. We introduce a computational method, called joint co-clustering, that can find co-clusters or groups of genes, bioimaging parameters and clinical traits that are believed to be closely related to each other based on the given empirical information. As bioimaging parameters, we quantify the expression of growth factor receptor EGFR/erb-B family in non-small cell lung carcinoma (NSCLC) through a fully-automated computer-aided analysis approach. This immunohistochemical analysis is usually performed by pathologists via visual inspection of tissue samples images. Our fully-automated techniques streamlines this error-prone and time-consuming process, thereby facilitating analysis and diagnosis. Experimental results for several real-life datasets demonstrate the high quantitative precision of our approach. The joint co-clustering method was tested with the receptor EGFR/erb-B family data on non-small cell lung carcinoma (NSCLC) tissue and identified statistically significant co-clusters of genes, receptor protein expression and clinical traits. The validation of our results with the literature suggest that the proposed method can provide biologically meaningful co-clusters of genes and traits and that it is a very promising approach to analyse large-scale biological data and to study multi-factorial genetic pathologies through their genetic alterations

Prognostic Significance and Clinicopathological Associations of COX-2 SNP in Patients with Nonsmall Cell Lung Cancer

Background. To further improve the screening, diagnosis, and therapy of patients with nonsmall cell lung cancer (NSCLC) additional diagnostic tools are urgently needed. Gene expression of Cyclooxygenase-2 (COX-2) has been linked to prognosis in patients with NSCLC. The role of the COX-2 926G>C Single Nucleotide Polymorphism (SNP) in patients with NSCLC remains unclear. The aim of this study was to investigate the potential of the COX-2 926G>C SNP as a molecular marker in this disease. Methods. COX-2 926G>C SNP was analyzed in surgically resected tumor tissue of 85 patients with NSCLC using a PCR-based RFLP technique. Results. The COX-2 926G>C SNP genotypes were detected with the following frequencies: GG n = 62 (73%), GC n = 20 (23%), CC n = 3 (4%). There were no associations between COX-2 SNP genotype and histology, grading or gender detectable. COX-2 SNP was significantly associated with tumor stage (P = .032) and lymph node status (P = .016, Chi-square test). With a median followup of 85.9 months, the median survival was 59.7 months. There were no associations seen between the COX-2 SNP genotype and patients prognosis. Conclusions. The COX-2 926G>C SNP is detectable at a high frequency in patients with NSCLC. The COX-2 926G>C SNP genotype is not a prognostic molecular marker in this disease. However, patients with the GC or CC genotype seem more susceptible to lymph node metastases and higher tumor stage than patients with the GG genotype. The results suggest COX-2 926G>C SNP as a molecular marker for lymph node involvement in this disease

Andrological and cytogenetic investigations of an infertile Przewalski's stallion

The case of an 8-year-old, sexually active but infertile Przewalski's stallion (Equus ferus przewalskii) was studied. Besides the infertility, the stallion also showed permanent problems with its body condition, being obviously weaker than all the other group members. The horse was kept in a separate place for two years with 12 mares in its harem group (six mares had foals earlier); however, none of the mares covered got pregnant. Andrological and cytogenetic investigations revealed underdeveloped testes, arrested spermatogenesis, azoospermia, and XY/XXY/X0 mosaicism. We classify the case as a mosaic Klinefelter syndrome, the first reported case in Przewalski's horse.Peer reviewe

COX-2 mRNA Expression is Significantly Increased in Acid-exposed Compared to Nonexposed Squamous Epithelium in Gastroesophageal Reflux Disease

Background: Little is known about the role of cyclooxygenase (COX)-2 in gastroesophageal reflux disease (GERD) and the development of Barrett's metaplasia. The objectives of this study were to further analyze COX-2 mRNA expression in patients with GERD compared to Barrett's esophagus (BE) and Barrett's cancer (BC). Methods: Tissue samples from 110 patients with GERD (n = 43), BE (n = 20), and BC (n = 47) were obtained in routine upper GI endoscopy. Expression levels of COX-2 were measured by quantitative real-time reverse trancriptase polymerase chain reaction (RT-PCR). Also, 24-h pH monitoring was performed in all patients of the GERD study group and the DeMeester composite score was used to match COX-2 mRNA expression with the severity of acid exposure in the lower esophagus. Results: COX-2 mRNA is progressively upregulated within the metaplasia-dysplasia-adenocarcinoma (MDA) sequence (p = 0.001). COX-2 levels of the squamous epithelium in the distal esophagus from patients with GERD and a pathologic mean DeMeester score (>14.72) were significantly higher than in patients with normal DeMeester scores (p = 0.01). Conclusion: In summary our findings suggest that alterations in COX-2 mRNA expression occur independently of endoscopic or histologic signs of GERD in the acid-exposed squamous epithelium of the distal esophagus. However, this early COX-2 increase in GERD is further upregulated within the MDA sequence for yet unknown reason

Epidermal growth factor receptor-regulated miR-125a-5p – a metastatic inhibitor of lung cancer

Both the epidermal growth factor receptor signaling pathway and microRNA (miRNA) play an important role in lung cancer development and progression. To address the potential role of miRNA in epidermal growth factor receptor signaling, we identified miR-125a-5p as a downstream target, using an miRNA array. We further demonstrated that miR-125a-5p inhibited migration and invasion of lung cancer cells. Moreover, miR-125a-5p regulated the expression of several downstream genes of epidermal growth factor receptor signaling. Importantly, examination of lung cancer samples revealed a significant correlation of miR-125a-5p repression with lung carcinogenesis. Taken together, our results provide compelling evidence that miR-125a-5p, an epidermal growth factor-signaling-regulated miRNA, may function as a metastatic suppressor