Lebenslaufgeschichte und Paarungssystem der Skorpionsfliege <i>Panorpa communis</i> L. (Mecoptera, Insecta)

Bei der Untersuchung des Paarungsverhaltens der Skorpionsfliege Panorpa communis zeigte sich, daß die verfügbare Nahrungsmenge die spezifische Gestalt des Paarungssystems in erheblichem Maße beeinflußt. Durch den starken Einfluß des Ernährungszustandes auf die Fitneß beider Geschlechter finden sich keine Unterschiede in der potentiellen Reproduktionsrate von Männchen und Weibchen, so daß sexuelle Selektion auf beide Geschlechter wirkt. Um eine Kopulation eingehen zu können, muß das Männchen dem Weibchen kostspielige Hochzeitsgeschenke in Form von Speichelsekrettropfen oder Futterstücken übergeben. Dies ist für ein Männchen mit hohem Energieaufwand verbunden, entscheidet aber über seinen Reproduktionserfolg, da die Weibchen mit steigendem Paarungsaufwand der Männchen eine zunehmend längere Kopulationsdauer gewähren ("cryptic female choice") und eine lange Lebenszeit-Kopulationsdauer vermutlich den entscheidenden proximaten Faktor der männlichen Fitneß darstellt. Die Fähigkeit eines Männchens viel Energie in einen hohen Paarungsaufwand zu investieren dient den Weibchen hierbei als täuschungssicheres Signal für die phänotypische Qualität des Männchens. Aufgrund dieses hohen Paarungsaufwandes der Männchen findet bei P. communis neben einer kryptischen Wahl phänotypisch guter Männchen durch die Weibchen auch ein Form von kryptischer Männchenwahl statt. Die Männchen diskriminieren zwischen Weibchen unterschiedlicher Fekundität und passen ihren Paarungsaufwand der Qualität der Weibchen (und damit der Zahl zu erwartender Nachkommen) an.A detector system for spatial resolved single molecule detection in molecular biological applications has been developed. An established method of single molecule detection is based on the detection of laser induced fluorescence of labeled bio-molecules in solution (fluorescence correlation spectroscopy). Based on this method a double-sided silicon micro-strip detector, which has been optimized for optical photons, in combination with a micro-channel image intensifier is used to achieve high spatial and time resolution, providing the sensitivity to detect the characteristic burst signature of fluorescence labeled bio-molecules. The detector data is transferred with a rate of 4 million frames per second to a dedicated parallel computer which does the online tracking of the molecules. The functionality of the detector system has been shown and signals of DNA molecules with 106 base pairs have successfully been detected

Rapid eradication of colon carcinoma by Clostridium perfringens Enterotoxin suicidal gene therapy

Background Bacterial toxins have evolved to an effective therapeutic option for cancer therapy. The Clostridium perfringens enterotoxin (CPE) is a pore- forming toxin with selective cytotoxicity. The transmembrane tight junction proteins claudin-3 and -4 are known high affinity CPE receptors. Their expression is highly upregulated in human cancers, including breast, ovarian and colon carcinoma. CPE binding to claudins triggers membrane pore complex formation, which leads to rapid cell death. Previous studies demonstrated the anti-tumoral effect of treatment with recombinant CPE-protein. Our approach aimed at evaluation of a selective and targeted cancer gene therapy of claudin-3- and/or claudin-4- expressing colon carcinoma in vitro and in vivo by using translation optimized CPE expressing vector. Methods In this study the recombinant CPE and a translation optimized CPE expressing vector (optCPE) was used for targeted gene therapy of claudin-3 and/or -4 overexpressing colon cancer cell lines. All experiments were performed in the human SW480, SW620, HCT116, CaCo-2 and HT-29 colon cancer and the isogenic Sk-Mel5 and Sk-Mel5 Cldn-3-YFP melanoma cell lines. Claudin expression analysis was done at protein and mRNA level, which was confirmed by immunohistochemistry. The CPE induced cytotoxicity was analyzed by the MTT cytotoxicity assay. In addition patient derived colon carcinoma xenografts (PDX) were characterized and used for the intratumoral in vivo gene transfer of the optCPE expressing vector in PDX bearing nude mice. Results Claudin-3 and -4 overexpressing colon carcinoma lines showed high sensitivity towards both recCPE application and optCPE gene transfer. The positive correlation between CPE cytotoxicity and level of claudin expression was demonstrated. Transfection of optCPE led to targeted, rapid cytotoxic effects such as membrane disruption and necrosis in claudin overexpressing cells. The intratumoral optCPE in vivo gene transfer led to tumor growth inhibition in colon carcinoma PDX bearing mice in association with massive necrosis due to the intratumoral optCPE expression. Conclusions This novel approach demonstrates that optCPE gene transfer represents a promising and efficient therapeutic option for a targeted suicide gene therapy of claudin-3 and/or claudin-4 overexpressing colon carcinomas, leading to rapid and effective tumor cell killing in vitro and in vivo

Alteration of Tissue Marking Dyes Depends on Used Chromogen during Immunohistochemistry

Pathological biopsy protocols require tissue marking dye (TMD) for orientation. In some cases (e.g., close margin), additional immunohistochemical analyses can be necessary. Therefore, the correlation between the applied TMD during macroscopy and the examined TMD during microscopy is crucial for the correct orientation, the residual tumour status and the subsequent therapeutic regime. In this context, our group observed colour changes during routine immunohistochemistry. Tissue specimens were marked with various TMD and processed by two different methods. TMD (blue, red, black, yellow and green) obtained from three different providers (A, B and C, and Whiteout/Tipp-Ex®) were used. Immunohistochemistry was performed manually via stepwise omission of reagents to identify the colour changing mechanism. Blue colour from provider A changed during immunohistochemistry into black, when 3,3′-Diaminobenzidine-tetrahydrochloride-dihydrate (DAB) and H2O2 was applied as an immunoperoxidase-based terminal colour signal. No other applied reagents, nor tissue texture or processing showed any influence on the colour. The remaining colours from provider A and the other colours did not show any changes during immunohistochemistry. Our results demonstrate an interesting and important pitfall in routine immunohistochemistry-based diagnostics that pathologists should be aware of. Furthermore, the chemical rationale behind the observed misleading colour change is discussed

Additional file 4: Figure S3. of Rapid eradication of colon carcinoma by Clostridium perfringens Enterotoxin suicidal gene therapy

Influence of optCPE in vivo gene transfer on body weight. Body weight of Co7515* PDX bearing mice was measured during tumor growth inhibition. In all animals no systemic toxicities, such as body weight loss, were observed, which strongly indicates the safety of this gene therapeutic approach. (JPG 283 kb

Additional file 2: Figure S1. of Rapid eradication of colon carcinoma by Clostridium perfringens Enterotoxin suicidal gene therapy

Knockdown of claudin-3 and -4 leads to reduced CPE activity in human colon cancer cells. a Sequences of used short interfering RNA (siRNA) targeting claudin-3 and -4. b Western blot analysis for claudin-3 and claudin-4 gene expression in human colon cancer cell lines SW480 (left panel) and HCT116 (right panel) 72 h after siRNA treatment, showing an efficient down-regulation of both with two independent siRNA compared to control (siCo). c Specific toxin responsiveness of claudin-3 and -4 down-regulated colon cancer cells. 72 h after siRNA transfection tumor cells were treated with recCPE at indicated concentrations for another 72 h. The cytotoxicity was determined by MTT assay and compared to siCo treated cells. A significantly reduced responsiveness (*** P < 0.0001) was demonstrated in both colon cancer cell lines, SW480 (left panel) and HCT116 (right panel). All assays were performed in two independent experiments and are expressed as mean percent of untreated control. Bars: SD. Level of significance was calculated by 2way-ANOVA (Bonferroni posttest). b Cytotoxicity of optCPE gene transfer in siRNA treated colon cancer cells and proof of claudin specificity. The siCldn3 + siCldn4 treated SW480 and HCT116 cells were transfected with optCPE construct 72 h after siRNA treatment. MTT assay was performed 72 h after CPE treatment and a significantly reduced CPE mediated cytotoxicity was observed in down-regulated SW480 (left panel) and also in HCT116 (right panel) cells compared to siCo treated cells. All assays were performed in two independent experiments and expressed as survival in optical density [OD]. Bars: SD. Level of significance was calculated by nonparametric, unpaired students t-test, *** P < 0.0001. Both assays demonstrate high selectivity of CPE on claudin-3 and -4 as down-regulated cells remain unaffected. (JPG 600 kb

Differential involvement of the posterior temporal cortex in mentalizing but not perspective taking

Understanding and predicting other people's mental states and behavior are important prerequisites for social interactions. The capacity to attribute mental states such as desires, thoughts or intentions to oneself or others is referred to as mentalizing. The right posterior temporal cortex at the temporal–parietal junction has been associated with mentalizing but also with taking someone else's spatial perspective onto the world—possibly an important prerequisite for mentalizing. Here, we directly compared the neural correlates of mentalizing and perspective taking using the same stimulus material. We found significantly increased neural activity in the right posterior segment of the superior temporal sulcus only during mentalizing but not perspective taking. Our data further clarify the role of the posterior temporal cortex in social cognition by showing that it is involved in processing information from socially salient visual cues in situations that require the inference about other people's mental states

Regional Variation of Chronic Kidney Disease in Germany: Results From Two Population-Based Surveys

Background/Aims: Due to the increasing prevalence of risk factors for chronic kidney disease (CKD), kidney dysfunction becomes a major public health problem. We investigated the CKD prevalence and determined to what extent the variation of risk factors explains the different CKD prevalence in Germany. Methods: We analyzed data from 6,054 participants, aged 31 to 82 years, from the Study of Health in Pomerania (SHIP-1) in Northeast Germany and the Cooperative Health Research in the Region of Augsburg (KORA F4) Study in Southern Germany. Regional differences in selected percentiles corresponding to the cutpoints for estimated glomerular filtration rate (eGFR, 2) and albumin-to-creatinine ratio (ACR, ≥30 mg/g) were tested using quantile regression models that adjusted for CKD risk factors. Results: The prevalence of decreased eGFRcreatinine-cystatinC (5.9 vs. 3.1 %, p creatinine-cystatinC and high ACR. Conclusions: The CKD prevalence is higher in Northeast than in Southern Germany. Differences in the prevalence of risk factors partly explain the higher disease burden of CKD in Northeast than in Southern Germany