The IgG1/G2 subclass shift – a sensitive, tissue non-specific marker for malignancy. Diagnostic performance with squamous cell carcinoma of the head and neck

A significant decrease in %IgG1 accompanied by an increase in %IgG2 in total serum IgG has been previously reported as a highly sensitive marker for detecting early stages of carcinomas of various localizations. Here we investigated the question as to whether this phenomenon is also observed in sera of patients with squamous cell carcinoma of the head–neck region (SCC-HN), and to evaluate its diagnostic performance in the post-operative monitoring. Using quantitative affinity chromatography, serum concentrations of IgG1, IgG2 and total IgG were determined in 81 patients with different stages of primary and untreated SCC-HN, in 51 SCC-HN patients in post-therapeutical follow up, and in 33 patients with organ matched benign diseases. The data were compared with a total of 174 healthy controls. It was found that (i) 105 SCC-HN patients exhibited a mean value of 56.0 ± 0.7% IgG1, which likewise differed from healthy controls (63.2 ± 0.5) and benign diseases (61.5 ± 1.0) with P < 0.0005, (ii) sensitivities and specificities for discriminating primary malignancies from healthy controls were 70 and 74% respectively, and from benign diseases 65 and 76%, (iii) highest sensitivities and specificities were observed with post-therapeutic cases suffering from tumour recurrence (88% and 75%) or patients with distant metastases (87% and 86%), (iv) apparently tumour-free post-therapeutic patients showed a mean %IgG1 not different from the normal value. The decrease in %IgG1 accompanied by increased %IgG2 is an efficient, sensitive and early marker of SCC-HN, which appears particularly useful for the post-therapeutic monitoring. © 1999 Cancer Research Campaig

Linking species concepts to natural product discovery in the post-genomic era

A widely accepted species concept for bacteria has yet to be established. As a result, species designations are inconsistently applied and tied to what can be considered arbitrary metrics. Increasing access to DNA sequence data and clear evidence that bacterial genomes are dynamic entities that include large numbers of horizontally acquired genes have added a new level of insight to the ongoing species concept debate. Despite uncertainties over how to apply species concepts to bacteria, there is clear evidence that sequence-based approaches can be used to resolve cohesive groups that maintain the properties of species. This cohesion is clearly evidenced in the genus Salinispora, where three species have been discerned despite very close relationships based on 16S rRNA sequence analysis. The major phenotypic differences among the three species are associated with secondary metabolite production, which occurs in species-specific patterns. These patterns are maintained on a global basis and provide evidence that secondary metabolites have important ecological functions. These patterns also suggest that an effective strategy for natural product discovery is to target the cultivation of new Salinispora taxa. Alternatively, bioinformatic analyses of biosynthetic genes provide opportunities to predict secondary metabolite novelty and reduce the redundant isolation of well-known metabolites. Although much remains to be learned about the evolutionary relationships among bacteria and how fundamental units of diversity can be resolved, genus and species descriptions remain the most effective method of scientific communication

Antiangiogenic Agents in Combination with Chemotherapy in Patients with Advanced Non-Small Cell Lung Cancer

Most patients with non-small cell lung cancer (NSCLC) present with advanced disease requiring systemic chemotherapy. Treatment with the antiangiogenic agent bevacizumab in combination with standard platinum-based doublet chemotherapy has been shown to improve outcomes in patients with advanced NSCLC. Several multitargeted antiangiogenic tyrosine kinase inhibitors (e.g., sorafenib, sunitinib, cediranib, vandetanib, BIBF 1120, pazopanib, and axitinib) are also being evaluated in combination with standard chemotherapy. Here we review current clinical data with combination therapy involving antiangiogenic agents and cytotoxic chemotherapy in patients with advanced NSCLC

Paediatric palliative home care by general paediatricians: a multimethod study on perceived barriers and incentives

<p>Abstract</p> <p>Background</p> <p>Non-specialist palliative care, as it is delivered by general practitioners, is a basic component of a comprehensive palliative care infrastructure for adult patients with progressive and far advanced disease. Currently palliative care for children and adolescents is recognized as a distinct entity of care, requiring networks of service providers across different settings, including paediatricians working in general practice. In Germany, the medical home care for children and adolescents is to a large extent delivered by general paediatricians working in their own practice. However, these are rarely confronted with children suffering from life-limiting diseases. The aim of this study was therefore to examine potential barriers, incentives, and the professional self-image of general paediatricians with regard to paediatric palliative care.</p> <p>Methods</p> <p>Based on qualitative expert interviews, a questionnaire was designed and a survey among general paediatricians in their own practice (n = 293) was undertaken. The survey has been developed and performed in close cooperation with the regional professional association of paediatricians.</p> <p>Results</p> <p>The results showed a high disposition on part of the paediatricians to engage in palliative care, and the majority of respondents regarded palliative care as part of their profile. Main barriers for the implementation were time restrictions (40.7%) and financial burden (31.6%), sole responsibility without team support (31.1%), as well as formal requirements such as forms and prescriptions (26.6%). Major facilitations were support by local specialist services such as home care nursing service (83.0%), access to a specialist paediatric palliative care consultation team (82.4%), as well as an option of exchange with colleagues (60.1%).</p> <p>Conclusions</p> <p>Altogether, the high commitment to this survey reflects the relevance of the issue for paediatricians working in general practice. Education in basic palliative care competence and communication skills was seen as an important prerequisite for the engagement in paediatric palliative home care. A local network of specialist support on site and a 24/7 on-call service are necessary in order to facilitate the implementation of basic palliative care by paediatricians in their own practice.</p

rst Transcriptional Activity Influences kirre mRNA Concentration in the Drosophila Pupal Retina during the Final Steps of Ommatidial Patterning

Background: Drosophila retinal architecture is laid down between 24-48 hours after puparium formation, when some of the still uncommitted interommatidial cells (IOCs) are recruited to become secondary and tertiary pigment cells while the remaining ones undergo apoptosis. This choice between survival and death requires the product of the roughest (rst) gene, an immunoglobulin superfamily transmembrane glycoprotein involved in a wide range of developmental processes. Both temporal misexpression of Rst and truncation of the protein intracytoplasmic domain, lead to severe defects in which IOCs either remain mostly undifferentiated and die late and erratically or, instead, differentiate into extra pigment cells. Intriguingly, mutants not expressing wild type protein often have normal or very mild rough eyes. Methodology/Principal Findings: By using quantitative real time PCR to examine rst transcriptional dynamics in the pupal retina, both in wild type and mutant alleles we showed that tightly regulated temporal changes in rst transcriptional rate underlie its proper function during the final steps of eye patterning. Furthermore we demonstrated that the unexpected wild type eye phenotype of mutants with low or no rst expression correlates with an upregulation in the mRNA levels of the rst paralogue kin-of-irre (kirre), which seems able to substitute for rst function in this process, similarly to their role in myoblast fusion. This compensatory upregulation of kirre mRNA levels could be directly induced in wild type pupa upon RNAi-mediated silencing of rst, indicating that expression of both genes is also coordinately regulated in physiological conditions. Conclusions/Significance: These findings suggest a general mechanism by which rst and kirre expression could be fine tuned to optimize their redundant roles during development and provide a clearer picture of how the specification of survival and apoptotic fates by differential cell adhesion during the final steps of retinal morphogenesis in insects are controlled at the transcriptional level

Anti-infectives in Drug Delivery-Overcoming the Gram-Negative Bacterial Cell Envelope.

Infectious diseases are becoming a major menace to the state of health worldwide, with difficulties in effective treatment especially of nosocomial infections caused by Gram-negative bacteria being increasingly reported. Inadequate permeation of anti-infectives into or across the Gram-negative bacterial cell envelope, due to its intrinsic barrier function as well as barrier enhancement mediated by resistance mechanisms, can be identified as one of the major reasons for insufficient therapeutic effects. Several in vitro, in silico, and in cellulo models are currently employed to increase the knowledge of anti-infective transport processes into or across the bacterial cell envelope; however, all such models exhibit drawbacks or have limitations with respect to the information they are able to provide. Thus, new approaches which allow for more comprehensive characterization of anti-infective permeation processes (and as such, would be usable as screening methods in early drug discovery and development) are desperately needed. Furthermore, delivery methods or technologies capable of enhancing anti-infective permeation into or across the bacterial cell envelope are required. In this respect, particle-based carrier systems have already been shown to provide the opportunity to overcome compound-related difficulties and allow for targeted delivery. In addition, formulations combining efflux pump inhibitors or antimicrobial peptides with anti-infectives show promise in the restoration of antibiotic activity in resistant bacterial strains. Despite considerable progress in this field however, the design of carriers to specifically enhance transport across the bacterial envelope or to target difficult-to-treat (e.g., intracellular) infections remains an urgently needed area of improvement. What follows is a summary and evaluation of the state of the art of both bacterial permeation models and advanced anti-infective formulation strategies, together with an outlook for future directions in these fields

“Microbiota, symbiosis and individuality summer school” meeting report

How does microbiota research impact our understanding of biological individuality? We summarize the interdisciplinary summer school on “Microbiota, symbiosis and individuality: conceptual and philosophical issues” (July 2019), which was supported by a European Research Council starting grant project “Immunity, DEvelopment, and the Microbiota” (IDEM). The summer school centered around interdisciplinary group work on four facets of microbiota research: holobionts, individuality, causation, and human health. The conceptual discussion of cutting-edge empirical research provided new insights into microbiota and highlights the value of incorporating into meetings experts from other disciplines, such as philosophy and history of science

Structure of S. aureus HPPK and the Discovery of a New Substrate Site Inhibitor

The first structural and biophysical data on the folate biosynthesis pathway enzyme and drug target, 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase (SaHPPK), from the pathogen Staphylococcus aureus is presented. HPPK is the second essential enzyme in the pathway catalysing the pyrophosphoryl transfer from cofactor (ATP) to the substrate (6-hydroxymethyl-7,8-dihydropterin, HMDP). In-silico screening identified 8-mercaptoguanine which was shown to bind with an equilibrium dissociation constant, Kd, of ∼13 µM as measured by isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR). An IC50 of ∼41 µM was determined by means of a luminescent kinase assay. In contrast to the biological substrate, the inhibitor has no requirement for magnesium or the ATP cofactor for competitive binding to the substrate site. The 1.65 Å resolution crystal structure of the inhibited complex showed that it binds in the pterin site and shares many of the key intermolecular interactions of the substrate. Chemical shift and 15N heteronuclear NMR measurements reveal that the fast motion of the pterin-binding loop (L2) is partially dampened in the SaHPPK/HMDP/α,β-methylene adenosine 5′-triphosphate (AMPCPP) ternary complex, but the ATP loop (L3) remains mobile on the µs-ms timescale. In contrast, for the SaHPPK/8-mercaptoguanine/AMPCPP ternary complex, the loop L2 becomes rigid on the fast timescale and the L3 loop also becomes more ordered – an observation that correlates with the large entropic penalty associated with inhibitor binding as revealed by ITC. NMR data, including 15N-1H residual dipolar coupling measurements, indicate that the sulfur atom in the inhibitor is important for stabilizing and restricting important motions of the L2 and L3 catalytic loops in the inhibited ternary complex. This work describes a comprehensive analysis of a new HPPK inhibitor, and may provide a foundation for the development of novel antimicrobials targeting the folate biosynthetic pathway

Recapitulation of tumor heterogeneity and molecular signatures in a 3D brain cancer model with decreased sensitivity to histone deacetylase inhibition

INTRODUCTION Physiologically relevant pre-clinical ex vivo models recapitulating CNS tumor micro-environmental complexity will aid development of biologically-targeted agents. We present comprehensive characterization of tumor aggregates generated using the 3D Rotary Cell Culture System (RCCS). METHODS CNS cancer cell lines were grown in conventional 2D cultures and the RCCS and comparison with a cohort of 53 pediatric high grade gliomas conducted by genome wide gene expression and microRNA arrays, coupled with immunohistochemistry, ex vivo magnetic resonance spectroscopy and drug sensitivity evaluation using the histone deacetylase inhibitor, Vorinostat. RESULTS Macroscopic RCCS aggregates recapitulated the heterogeneous morphology of brain tumors with a distinct proliferating rim, necrotic core and oxygen tension gradient. Gene expression and microRNA analyses revealed significant differences with 3D expression intermediate to 2D cultures and primary brain tumors. Metabolic profiling revealed differential profiles, with an increase in tumor specific metabolites in 3D. To evaluate the potential of the RCCS as a drug testing tool, we determined the efficacy of Vorinostat against aggregates of U87 and KNS42 glioblastoma cells. Both lines demonstrated markedly reduced sensitivity when assaying in 3D culture conditions compared to classical 2D drug screen approaches. CONCLUSIONS Our comprehensive characterization demonstrates that 3D RCCS culture of high grade brain tumor cells has profound effects on the genetic, epigenetic and metabolic profiles of cultured cells, with these cells residing as an intermediate phenotype between that of 2D cultures and primary tumors. There is a discrepancy between 2D culture and tumor molecular profiles, and RCCS partially re-capitulates tissue specific features, allowing drug testing in a more relevant ex vivo system