Systematic analysis of cell cycle effects of common drugs leads to the discovery of a suppressive interaction between gemfibrozil and fluoxetine

Screening chemical libraries to identify compounds that affect overall cell proliferation is common. However, in most cases, it is not known whether the compounds tested alter the timing of particular cell cycle transitions. Here, we evaluated an FDA-approved drug library to identify pharmaceuticals that alter cell cycle progression in yeast, using DNA content measurements by flow cytometry. This approach revealed strong cell cycle effects of several commonly used pharmaceuticals. We show that the antilipemic gemfibrozil delays initiation of DNA replication, while cells treated with the antidepressant fluoxetine severely delay progression through mitosis. Based on their effects on cell cycle progression, we also examined cell proliferation in the presence of both compounds. We discovered a strong suppressive interaction between gemfibrozil and fluoxetine. Combinations of interest among diverse pharmaceuticals are difficult to identify, due to the daunting number of possible combinations that must be evaluated. The novel interaction between gemfibrozil and fluoxetine suggests that identifying and combining drugs that show cell cycle effects might streamline identification of drug combinations with a pronounced impact on cell proliferation.     

Bioanalytical application of surface‐ and tip‐enhanced Raman spectroscopy

Due to its fingerprint specificity and trace‐level sensitivity, surface‐enhanced Raman spectroscopy (SERS) is an attractive tool in bioanalytics. This review reflects the research in this highly interesting topic of the last 3–4 years. The detection of the SERS signature of biomolecules up to microorganisms and cells is introduced. Labeling using modified nanoparticles (SERS tags) is also introduced. In order to establish biomedical applications, SERS analysis is performed in complex matrices such as body fluids. Furthermore, the SERS technique is combined with other methods such as microfluidic devices for online monitoring and scanning probe microscopy (i.e. tip‐enhanced Raman spectroscopy, TERS) to investigate nanoscaled features. The present review illustrates the broad application fields of SERS and TERS in bioanalytics and shows the great potential of these methods for biomedical diagnostics.     

Autophagy and mitochondria in Pompe disease: nothing is so new as what has long been forgotten

Macroautophagy (often referred to as autophagy) is an evolutionarily conserved intracellular system by which macromolecules and organelles are delivered to lysosomes for degradation and recycling. Autophagy is robustly induced in response to starvation in order to generate nutrients and energy through the lysosomal degradation of cytoplasmic components. Constitutive, basal autophagy serves as a quality control mechanism for the elimination of aggregated proteins and worn-out or damaged organelles, such as mitochondria. Research during the last decade has made it clear that malfunctioning or failure of this system is associated with a wide range of human pathologies and age-related diseases. Our recent data provide strong evidence for the role of autophagy in the pathogenesis of Pompe disease, a lysosomal glycogen storage disease caused by deficiency of acid alpha-glucosidase (GAA). Large pools of autophagic debris in skeletal muscle cells can be seen in both our GAA knockout model and patients with Pompe disease. In this review, we will focus on these recent data, and comment on the not so recent observations pointing to the involvement of autophagy in skeletal muscle damage in Pompe disease.     

Microtubule-dependent mRNA transport in the model microorganism Ustilago maydis

Microtubule-dependent trafficking is essential in moving mRNAs over long distances. This transport mechanism regulates important cellular events such as determining polarity and local protein secretion. Key examples are developmental and neuronal processes studied in Drosophila melanogaster, Xenopus laevis as well as in mammalian cells. A simple eukaryotic system to uncover basic mechanisms was missing. Fungal models are generally well suited for this purpose, since transgenic strains can be generated easily by homologous recombination allowing in vivo studies at native expression levels. Substantial advances in understanding Ustilago maydis showed that this fungus fulfils important criteria to serve as model for microtubule-dependent mRNA trafficking. Here, we summarize progress focusing on target mRNAs, RNA localization elements, RNA-binding proteins, mRNPs, molecular motors and microtubule organization. This serves as the basis to discuss the novel mechanism of mRNP hitchhiking on endosomes as well as an unexpected link to unconventional secretion with its implications for applied sciences.     

Involvement of CXCR4 Chemokine Receptor in Metastastic HER2-Positive Esophageal Cancer

A functional linkage of the structurally unrelated receptors HER2 and CXCR4 has been suggested for breast cancer but has not been evaluated for esophageal carcinoma. The inhibition of HER2 leads to a reduction of primary tumor growth and metastases in an orthotopic model of esophageal carcinoma. The chemokine receptor CXCR4 has been implicated in metastatic dissemination of various tumors and correlates with poor survival in esophageal carcinoma. The aim of this study was to investigate a correlation between the expression levels of HER2 and CXCR4 and to evaluate the involvemnent of CXCR4-expression in HER2-positive esophageal carcinoma. The effects of HER2-inhibition with trastuzumab and of CXCR4-inhibition with AMD3100 on primary tumor growth, metastatic homing, and receptor expression were evaluated in vitro and in an orthotopic model of metastatic esophageal carcinoma using MRI for imaging. The clinical relevance of HER2- and CXCR4-expression was examined in esophageal carcinoma patients. A significant correlation of HER2- and CXCR4-expression in primary tumor and metastases exists in the orthotopic model. Trastuzumab and AMD3100 treatment led to a significant reduction of primary tumor growth, metastases and micrometastases. HER2-expression was significantly elevated under AMD3100 treatment in the primary tumor and particularly in the metastases. The positive correlation between HER2- and CXCR4-expression was validated in esophageal cancer patients. The correlation of CXCR4- and HER2-expression and the elevation of HER2-expression and reduction of metastases through CXCR4-inhibition suggest a possible functional linkage and a role in tumor dissemination in HER2-positive esophageal carcinoma.     

Finding “Space” for Comanagement of Forests within the Neoliberal Paradigm: Rights,Strategies, and Tools for Asserting a Local Agenda

As neoliberalism continues to influence environmental governance, it affects notions about the appropriate level of community involvement in resource management. Under more recent iterations, hybrid forms of governance are emphasized, including government–civil society partnerships and approaches geared towards harnessing the strengths of local communities. Here we explore the characteristics of different resource management rights, strategies, and tools through which communities can find political space to assert their own agendas within a neoliberalized policy environment. We examine the successful use of some of these approaches by communities during the initial development of community forests policy and practice in British Columbia, Canada. While we confirm the complex, contingent and case-specific nature of opportunities for comanagement created through neoliberal policy elements, we suggest that space does exist for community forest bodies to assert local values, goals and strategies, demonstrating the creativity, ingenuity and determination of communities to attain a real voice in management.

Mouse models for studying pacemaker channel function and sinus node arrhythmia

Pacemaker activity of the heart is generated by a small group of cells forming the sinoatrial node (SAN). Cells of the SAN are spontaneously active and generate action potentials with remarkable regularity and stability under all physiological conditions. The exact molecular mechanisms underlying pacemaker potentials in the SAN have not yet been fully elucidated. Several voltage-dependent ion channels as well as intracellular calcium cycling processes are thought to contribute to the pacemaker activity. Hyperpolarization-activated cation channels, which generate the I_f current, have biophysical properties which seem ideally suited for the initiation of spontaneous electrical activity. This review describes recent work on several transgenic mice lacking different cardiac HCN channel subtypes. The role of I_f for normal pacemaking and sinus node arrhythmia as revealed by these genetic models will be discussed. In addition, a new mouse line is described which enables gene targeting in a temporally-controlled manner selectively in SAN cells. Elucidating the function of HCN and other ion channels in well-controlled mouse models should ultimately lead to a better understanding of the mechanisms underlying human sinoatrial arrhythmias.     

Cupiennius salei and Achaearanea tepidariorum: Spider models for investigating evolution and development

The spiders Cupiennius salei and Achaearanea tepidariorum are firmly established laboratory models that have already contributed greatly to answering evolutionary developmental questions. Here we appraise why these animals are such useful models from phylogeny, natural history and embryogenesis to the tools available for their manipulation. We then review recent studies of axis formation, segmentation, appendage development and neurogenesis in these spiders and how this has contributed to understanding the evolution of these processes. Furthermore, we discuss the potential of comparisons of silk production between Cupiennius and Achaearanea to investigate the origins and diversification of this evolutionary innovation. We suggest that further comparisons between these two spiders and other chelicerates will prove useful for understanding the evolution of development in metazoans.     

Isolation and characterization of 13 microsatellite loci for Percichthys trucha (Percichthyidae)

Thirteen polymorphic microsatellite loci are described for the South American freshwater fish Percichthys trucha. Number of alleles per locus ranged from two to 21 and observed heterozygosities ranged from 0.304 to 0.915 in a sample of 47 individuals from four different sampling locations.     

Isolation and identification of eight microsatellite loci in the Cherokee darter (Etheostoma scotti) and their variability in other members of the genera Etheostoma, Ammocrypta, and Percina

The Cherokee darter Etheostoma scotti is a federally threatened fish endemic to the Etowah River system of northwest Georgia. In order to analyse the population structure and genetic diversity of this fish, eight tetranucleotide microsatellite genetic markers were developed. The marker set was applied to 13 additional darter species to test cross-species amplification and polymorphism. Successful amplification was obtained for all eight loci in each of the 13 other species of darters, with between seven and eight polymorphic loci per species.