Basement Membrane-Rich Organoids with Functional Human Blood Vessels Are Permissive Niches for Human Breast Cancer Metastasis
Ángel M. Cuesta
Ana M. Álvarez-Méndez
- Metastasic breast cancer is the leading cause of death by malignancy in women worldwide. Tumor metastasis is a multistep process encompassing local invasion of cancer cells at primary tumor site, intravasation into the blood vessel, survival in systemic circulation, and extravasation across the endothelium to metastasize at a secondary site. However, only a small percentage of circulating cancer cells initiate metastatic colonies. This fact, together with the inaccessibility and structural complexity of target tissues has hampered the study of the later steps in cancer metastasis. In addition, most data are derived from in vivo models where critical steps such as intravasation/extravasation of human cancer cells are mediated by murine endothelial cells. Here, we developed a new mouse model to study the molecular and cellular mechanisms underlying late steps of the metastatic cascade. We have shown that a network of functional human blood vessels can be formed by co-implantation of human endothelial cells and mesenchymal cells, embedded within a reconstituted basement membrane-like matrix and inoculated subcutaneously into immunodeficient mice. The ability of circulating cancer cells to colonize these human vascularized organoids was next assessed in an orthotopic model of human breast cancer by bioluminescent imaging, molecular techniques and immunohistological analysis. We demonstrate that disseminated human breast cancer cells efficiently colonize organoids containing a functional microvessel network composed of human endothelial cells, connected to the mouse circulatory system. Human breast cancer cells could be clearly detected at different stages of the metastatic process: initial arrest in the human microvasculature, extravasation, and growth into avascular micrometastases. This new mouse model may help us to map the extravasation process with unprecedented detail, opening the way for the identification of relevant targets for therapeutic intervention.
On functional module detection in metabolic networks
- Functional modules of metabolic networks are essential for understanding the metabolism of an organism as a whole. With the vast amount of experimental data and the construction of complex and large-scale, often genome-wide, models, the computer-aided identification of functional modules becomes more and more important. Since steady states play a key role in biology, many methods have been developed in that context, for example, elementary flux modes, extreme pathways, transition invariants and place invariants. Metabolic networks can be studied also from the point of view of graph theory, and algorithms for graph decomposition have been applied for the identification of functional modules. A prominent and currently intensively discussed field of methods in graph theory addresses the Q-modularity. In this paper, we recall known concepts of module detection based on the steady-state assumption, focusing on transition-invariants (elementary modes) and their computation as minimal solutions of systems of Diophantine equations. We present the Fourier-Motzkin algorithm in detail. Afterwards, we introduce the Q-modularity as an example for a useful non-steady-state method and its application to metabolic networks. To illustrate and discuss the concepts of invariants and Q-modularity, we apply a part of the central carbon metabolism in potato tubers (Solanum tuberosum) as running example. The intention of the paper is to give a compact presentation of known steady-state concepts from a graph-theoretical viewpoint in the context of network decomposition and reduction and to introduce the application of Q-modularity to metabolic Petri net models.
Aesthetic and emotional effects of meter and rhyme in poetry
Martin von Koppenfels
Sonja A. Kotz
- Metrical patterning and rhyme are frequently employed in poetry but also in infant-directed speech, play, rites, and festive events. Drawing on four line-stanzas from nineteenth and twentieth German poetry that feature end rhyme and regular meter, the present study tested the hypothesis that meter and rhyme have an impact on aesthetic liking, emotional involvement, and affective valence attributions. Hypotheses that postulate such effects have been advocated ever since ancient rhetoric and poetics, yet they have barely been empirically tested. More recently, in the field of cognitive poetics, these traditional assumptions have been readopted into a general cognitive framework. In the present experiment, we tested the influence of meter and rhyme as well as their interaction with lexicality in the aesthetic and emotional perception of poetry. Participants listened to stanzas that were systematically modified with regard to meter and rhyme and rated them. Both rhyme and regular meter led to enhanced aesthetic appreciation, higher intensity in processing, and more positively perceived and felt emotions, with the latter finding being mediated by lexicality. Together these findings clearly show that both features significantly contribute to the aesthetic and emotional perception of poetry and thus confirm assumptions about their impact put forward by cognitive poetics. The present results are explained within the theoretical framework of cognitive fluency, which links structural features of poetry with aesthetic and emotional appraisal.
Prospective evaluation of artemether-lumefantrine for the treatment of non-falciparum and mixed-species malaria in Gabon
Daisy A. Diop
Ayola A. Adegnika
Peter G. Kremsner
- Background: The recommendation of artemisinin combination therapy (ACT) as first-line treatment for uncomplicated falciparum malaria is supported by a plethora of high quality clinical trials. However, their recommendation for the treatment of mixed-species malaria and the large-scale use for the treatment of non-falciparum malaria in endemic regions is based on anecdotal rather than systematic clinical evidence.
Methods: This study prospectively observed the efficacy of artemether-lumefantrine for the treatment of uncomplicated non-falciparum or mixed-species malaria in two routine district hospitals in the Central African country of Gabon.
Results: Forty patients suffering from uncomplicated Plasmodium malariae, Plasmodium ovale or mixed-species malaria (including Plasmodium falciparum) presenting at the hospital received artemether-lumefantrine treatment and were followed up. All evaluable patients (n = 38) showed an adequate clinical and parasitological response on Day 28 after oral treatment with artemether-lumefantrine (95% confidence interval: 0.91,1). All adverse events were of mild to moderate intensity and completely resolved by the end of study.
Conclusions: This first systematic assessment of artemether-lumefantrine treatment for P. malariae, P. ovale and mixed-species malaria demonstrated a high cure rate of 100% and a favourable tolerability profile, and thus lends support to the practice of treating non-falciparum or mixed-species malaria, or all cases of malaria without definite species differentiation, with artemether-lumefantrine in Gabon.
Trial Registration: ClinicalTrials.gov Identifier: NCT00725777
Identity development in adolescents with mental problems
- Background: In the revision of the Diagnostic and Statistical Manual (DSM-5), “Identity” is an essential diagnostic criterion for personality disorders (self-related personality functioning) in the alternative approach to the diagnosis of personality disorders in Section III of DSM-5. Integrating a broad range of established identity concepts, AIDA (Assessment of Identity Development in Adolescence) is a new questionnaire to assess pathology-related identity development in healthy and disturbed adolescents aged 12 to 18 years. Aim of the present study is to investigate differences in identity development between adolescents with different psychiatric diagnoses.
Methods: Participants were 86 adolescent psychiatric in- and outpatients aged 12 to 18 years. The test set includes the questionnaire AIDA and two semi-structured psychiatric interviews (SCID-II, K-DIPS). The patients were assigned to three diagnostic groups (personality disorders, internalizing disorders, externalizing disorders). Differences were analyzed by multivariate analysis of variance MANOVA.
Results: In line with our hypotheses, patients with personality disorders showed the highest scores in all AIDA scales with T>70. Patients with externalizing disorders showed scores in an average range compared to population norms, while patients with internalizing disorders lay in between with scores around T=60. The AIDA total score was highly significant between the groups with a remarkable effect size of f= 0.44.
Conclusion: Impairment of identity development differs between adolescent patients with different forms of mental disorders. The AIDA questionnaire is able to discriminate between these groups. This may help to improve assessment and treatment of adolescents with severe psychiatric problems.
Chemotherapy-Induced Peripheral Neuropathy in Cancer Patients: A Four-Arm Randomized Trial on the Effectiveness of Electroacupuncture
Hans Helge Bartsch
- Purpose. Chemotherapy-induced peripheral neuropathy (CIPN) is a common and dose-limiting side effect of cytostatic drugs. Since there are no proven therapeutic procedures against CIPN, we were interested to define the role of electroacupuncture (EA) from which preliminary data showed promising results. Methods. In a randomized trial with a group sequential adaptive design in patients with CIPN, we compared EA (LV3, SP9, GB41, GB34, LI4, LI11, SI3, and HT3; n=14) with hydroelectric baths (HB, n=14), vitamin B1/B6 capsules (300/300 mg daily; VitB, n=15), and placebo capsules (n=17). The statistical power in this trial was primarily calculated for proving EA only, so results of HB and VitB are pilot data. Results. CIPN complaints improved by 0.8 +- 1.2 (EA), 1.7 +- 1.7 (HB), 1.6 +- 2.0 (VitB), and 1.3 +- 1.3 points (placebo) on a 10-point numeric rating scale without significant difference between treatment groups or placebo. In addition no significant differences in sensory nerve conduction studies or quality of life (EORTC QLQ-C30) were found. Conclusions. The used EA concept, HB, and VitB were not superior to placebo. Since, contrary to our results, studies with different acupuncture concepts showed a positive effect on CIPN, the effect of acupuncture on CIPN remains unclear. Further randomized, placebo controlled studies seem necessary. This trial is registered with DRKS00004448.
HIF1A Reduces Acute Lung Injury by Optimizing Carbohydrate Metabolism in the Alveolar Epithelium
Christoph H. Borchers
Thomas J. Mariani
Douglas J. Kominsky
Holger K. Eltzschig
- Background: While acute lung injury (ALI) contributes significantly to critical illness, it resolves spontaneously in many instances. The majority of patients experiencing ALI require mechanical ventilation. Therefore, we hypothesized that mechanical ventilation and concomitant stretch-exposure of pulmonary epithelia could activate endogenous pathways important in lung protection.
Methods and Findings: To examine transcriptional responses during ALI, we exposed pulmonary epithelia to cyclic mechanical stretch conditions—an in vitro model resembling mechanical ventilation. A genome-wide screen revealed a transcriptional response similar to hypoxia signaling. Surprisingly, we found that stabilization of hypoxia-inducible factor 1A (HIF1A) during stretch conditions in vitro or during ventilator-induced ALI in vivo occurs under normoxic conditions. Extension of these findings identified a functional role for stretch-induced inhibition of succinate dehydrogenase (SDH) in mediating normoxic HIF1A stabilization, concomitant increases in glycolytic capacity, and improved tricarboxylic acid (TCA) cycle function. Pharmacologic studies with HIF activator or inhibitor treatment implicated HIF1A-stabilization in attenuating pulmonary edema and lung inflammation during ALI in vivo. Systematic deletion of HIF1A in the lungs, endothelia, myeloid cells, or pulmonary epithelia linked these findings to alveolar-epithelial HIF1A. In vivo analysis of 13C-glucose metabolites utilizing liquid-chromatography tandem mass-spectrometry demonstrated that increases in glycolytic capacity, improvement of mitochondrial respiration, and concomitant attenuation of lung inflammation during ALI were specific for alveolar-epithelial expressed HIF1A.
Conclusions: These studies reveal a surprising role for HIF1A in lung protection during ALI, where normoxic HIF1A stabilization and HIF-dependent control of alveolar-epithelial glucose metabolism function as an endogenous feedback loop to dampen lung inflammation.
Personalizing HIV Therapy, Mission Impossible?
Nils von Hentig
- Sustained HIV suppression depends on a number of factors including therapy adherence, management of side effects, viral resistance and individual characteristics of patients and therapeutic settings. Treatment response rates range up to 90% in therapy naïve patients but decline to approximately 50% in patients who received several antiretrovirals during treatment history. Furthermore, HIV protease inhibitors (PI) and non nucleoside reverse transcriptase inhibitors (NNRTI) plasma concentrations display high inter- and intra individual variability and the therapeutic window is comparably narrow. In this therapeutic setting the personalization of dosing regimens has been suggested in many cases to tailor the ARV plasma concentrations with the intention to maximize therapy success and minimize side effects in the individual. However, personalizing therapy by modifying the dosing regimen bears the danger of losing therapeutic efficacy, increasing side effects or causing viral resistance.
This topical review identifies pharmacokinetic and pharmacodynamic models of antiretroviral therapy appraising the potential application to HIV therapy and discusses its future in the light of new drug classes and fix-dose combinations.
Non-equivalence of antibiotic generic drugs and risk for intensive care
Charles James Kirkpatrick
- Background: The underlying axiom in applying generic drugs is the equivalence of their active ingredient with the (usually more expensive) innovator product, an all-embracing statement with the insidious result that physicians assume that the generic products have been subjected to the same rigorous testing regimens as the brand-name products. The present paper presents novel experimental data on an investigator-blinded comparison between the innovator imipenem antibiotic, and a number of its generics.
Methods: Particulate matter contamination of each group was visualized by means of a membrane filter method. Functional studies in an animal model–the dorsal skinfold chamber technique in mice-designed to simulate the state of microcirculatory dysfunction in intensive care patients was performed, in order to assess the influence of the particulate matter of each group on the functional capillary density of the striated skin muscle, after their intravenous injection.
Results: The results showed massive particulate contamination of the generics, in a size range relevant for impacting the microcirculation. The particulate contamination contributed in some generic groups to a significant shutdown of tissue perfusion.
Conclusion: The presented data underscore the need to raise the regulatory barriers for the entry of generics to the market, well beyond the simplistic proof of “bioequivalence”, which in no measure deals with the essential questions of quality and patient safety. If generics are used, they should be tested by a filter technique and optical microscopy, to ensure the absence especially of small particulate contaminants and their purity.
Biglycan: a multivalent proteoglycan providing structure and signals
Madalina V. Nastase
Marian F. Young
- Research over the past few years has provided fascinating results indicating that biglycan, besides being a ubiquitous structural component of the extracellular matrix (ECM), may act as a signaling molecule. Proteolytically released from the ECM, biglycan acts as a danger signal signifying tissue stress or injury. As a ligand of innate immunity receptors and activator of the inflammasome, biglycan stimulates multifunctional proinflammatory signaling linking the innate to the adaptive immune response. By clustering several types of receptors on the cell surface and orchestrating their downstream signaling events, biglycan is capable to autonomously trigger sterile inflammation and to potentiate the inflammatory response to microbial invasion. Besides operating in a broad biological context, biglycan also displays tissue-specific affinities to certain receptors and structural components, thereby playing a crucial role in bone formation, muscle integrity, and synapse stability at the neuromuscular junction. This review attempts to provide a concise summary of recent data regarding the involvement of biglycan in the regulation of inflammation and the musculoskeletal system, pointing out both a signaling and a structural role for this proteoglycan. The potential of biglycan as a novel therapeutic target or agent for the treatment of inflammatory diseases and skeletal muscular dystrophies is also addressed.