16 research outputs found

    Oncologic Thermoradiotherapy: Need for Evidence, Harmonisation, and Innovation

    Get PDF
    The road of acceptance of oncologic thermotherapy/hyperthermia as a synergistic modality in combination with standard oncologic therapies is still bumpy. This is partially due to the lack of level I evidence from international, multicentric, randomized clinical trials including large patient numbers and a long term follow-up. Therefore we need more level I EVIDENCE from clinical trials, we need HARMONISATION and global acceptance for existing technologies and a common language understood by all stakeholders and we need INNOVATION in the fields of biology, clinics and technology to move thermotherapy/hyperthermia forward. This is the main focus of this reprint. In this reprintyou find carefully selected and peer-reviewed contributions from Africa, America, Asia, and Europe. The published papers from leading scientists from all over the world covering a broad range of timely research topics might also help to strengthen thermotherapy on a global level

    Determination and Implications of Physicochemical Properties of the Brain

    Get PDF
    Electroosmotic flow is a bulk fluid flow that influences solute transport through capillary conduits and porous material under the influence of an electric field. The magnitude of electroosmotic flow is proportional to the zeta-potential of the capillary or porous material. A porous material such as living tissue would need to have an appreciable zeta-potential to create electroosmotic flow in the interstitial space. Transporting solutes in and out of tissue by virtue of electroosmotic flow in principle has advantages such as avoiding pressure effects and sample dilution that accompany micropush-pull and microdialysis approaches. In order to assess the viability of this approach, it is necessary to know the zeta-potential in the tissue of interest. To address this, a method and apparatus was developed to measure the zeta-potential and tortuosity in tissue slices. The method was applied to organotypic hippocampal slice cultures. The apparatus was improved on in order to provide feedback control to maintain a constant electric field through the tissue culture. The zeta-potential of the organotypic tissue culture is -22 ± 0.8 mV and the tortuosity is 2.24 ± 0.10. With a zeta-potential of -22 mV, low electric fields applied to the brain will create electroosmotic flow. Electroosmotic flow can be directed to transport extracellular fluid from brain tissue into a conduit such as a sampling capillary. Furthermore, electroosmotic flow can be used in the opposite way to eject fluid and solutes from a capillary or pipette into brain tissue. The electroosmotic effect may be important in the widely used solute delivery method of iontophoresis. In iontophoresis, solutes are ejected into tissue via an applied current. Once in the tissue, solute transport is affected by the electroosmotic flow in the tissue and thus depends on the tissue zeta-potential. The dependence of solute transport on zeta-potential is illustrated using a set of poly(acrylamide-co-acrylic acid) hydrogels. A method of measuring the thickness of organotypic tissue cultures has also been developed. Characterization of zeta-potential and tortuosity provides the fundamentals for understanding electroosmotic flow through the extracellular space of brain tissue

    [<sup>18</sup>F]fluorination of biorelevant arylboronic acid pinacol ester scaffolds synthesized by convergence techniques

    Get PDF
    Aim: The development of small molecules through convergent multicomponent reactions (MCR) has been boosted during the last decade due to the ability to synthesize, virtually without any side-products, numerous small drug-like molecules with several degrees of structural diversity.(1) The association of positron emission tomography (PET) labeling techniques in line with the “one-pot” development of biologically active compounds has the potential to become relevant not only for the evaluation and characterization of those MCR products through molecular imaging, but also to increase the library of radiotracers available. Therefore, since the [18F]fluorination of arylboronic acid pinacol ester derivatives tolerates electron-poor and electro-rich arenes and various functional groups,(2) the main goal of this research work was to achieve the 18F-radiolabeling of several different molecules synthesized through MCR. Materials and Methods: [18F]Fluorination of boronic acid pinacol esters was first extensively optimized using a benzaldehyde derivative in relation to the ideal amount of Cu(II) catalyst and precursor to be used, as well as the reaction solvent. Radiochemical conversion (RCC) yields were assessed by TLC-SG. The optimized radiolabeling conditions were subsequently applied to several structurally different MCR scaffolds comprising biologically relevant pharmacophores (e.g. β-lactam, morpholine, tetrazole, oxazole) that were synthesized to specifically contain a boronic acid pinacol ester group. Results: Radiolabeling with fluorine-18 was achieved with volumes (800 μl) and activities (≤ 2 GBq) compatible with most radiochemistry techniques and modules. In summary, an increase in the quantities of precursor or Cu(II) catalyst lead to higher conversion yields. An optimal amount of precursor (0.06 mmol) and Cu(OTf)2(py)4 (0.04 mmol) was defined for further reactions, with DMA being a preferential solvent over DMF. RCC yields from 15% to 76%, depending on the scaffold, were reproducibly achieved. Interestingly, it was noticed that the structure of the scaffolds, beyond the arylboronic acid, exerts some influence in the final RCC, with electron-withdrawing groups in the para position apparently enhancing the radiolabeling yield. Conclusion: The developed method with high RCC and reproducibility has the potential to be applied in line with MCR and also has a possibility to be incorporated in a later stage of this convergent “one-pot” synthesis strategy. Further studies are currently ongoing to apply this radiolabeling concept to fluorine-containing approved drugs whose boronic acid pinacol ester precursors can be synthesized through MCR (e.g. atorvastatin)

    Diagnostic Significance of Exosomal miRNAs in the Plasma of Breast Cancer Patients

    Get PDF
    Poster Session AbstractsBackground and Aims: Emerging evidence that microRNAs (miRNAs) play an important role in cancer development has opened up new opportunities for cancer diagnosis. Recent studies demonstrated that released exosomes which contain a subset of both cellular mRNA and miRNA could be a useful source of biomarkers for cancer detection. Here, we aim to develop a novel biomarker for breast cancer diagnosis using exosomal miRNAs in plasma. Methods: We have developed a rapid and novel isolation protocol to enrich tumor-associated exosomes from plasma samples by capturing tumor specific surface markers containing exosomes. After enrichment, we performed miRNA profiling on four sample sets; (1) Ep-CAM marker enriched plasma exosomes of breast cancer patients; (2) breast tumors of the same patients; (3) adjacent non-cancerous tissues of the same patients; (4) Ep-CAM marker enriched plasma exosomes of normal control subjects. Profiling is performed using PCR-based array with human microRNA panels that contain more than 700 miRNAs. Results: Our profiling data showed that 15 miRNAs are concordantly up-regulated and 13 miRNAs are concordantly down-regulated in both plasma exosomes and corresponding tumors. These account for 25% (up-regulation) and 15% (down-regulation) of all miRNAs detectable in plasma exosomes. Our findings demonstrate that miRNA profile in EpCAM-enriched plasma exosomes from breast cancer patients exhibit certain similar pattern to that in the corresponding tumors. Based on our profiling results, plasma signatures that differentiated breast cancer from control are generated and some of the well-known breast cancer related miRNAs such as miR-10b, miR-21, miR-155 and miR-145 are included in our panel list. The putative miRNA biomarkers are validated on plasma samples from an independent cohort from more than 100 cancer patients. Further validation of the selected markers is likely to offer an accurate, noninvasive and specific diagnostic assay for breast cancer. Conclusions: These results suggest that exosomal miRNAs in plasma may be a novel biomarker for breast cancer diagnosis.link_to_OA_fulltex
    corecore