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1.
Urol Int ; 106(5): 431-439, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35144260

RESUMO

BACKGROUND: Focal therapy (FT) is an option to treat localized prostate cancer (PCa) and preserve healthy prostate tissue in order to reduce known side effects from primary whole-gland treatment. The available FT modalities are manifold. Until now, national and international PCa guidelines have been cautious to propose recommendations regarding FT treatment since data from prospective controlled trials are lacking for most FT modalities. Moreover, none of the international guidelines provides a separate section on FT. In this purpose, we provide a synopsis of the consensus-based German S3 guidelines for a possible international use. SUMMARY: The recently published update of the German S3 guidelines, an evidence- and consensus-based guideline, provides a section on FT with recommendations for diagnostic work-up, indications, modalities, and follow-up. This section consists of 12 statements and recommendations for FT in the treatment of localized PCa. KEY MESSAGE: The German S3 guidelines on PCa are the first to incorporate recommendations for FT based on evidence and expert consensus including indication criteria for FT, pretreatment, and follow-up diagnostic pathways as well as an extended overview of FT techniques and the current supportive evidence.


Assuntos
Neoplasias da Próstata , Crioterapia , Humanos , Masculino , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia
2.
Appl Microbiol Biotechnol ; 104(1): 405-415, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31832709

RESUMO

Recently Legionella pneumophila is the main causative waterborne organism of severe respiratory infections. Additionally, other Legionella species are documented as human pathogens. In our work, we describe a rapid detection method which combines two advantages for sensitive and specific detection of the genus Legionella: the fast isothermal amplification method "Loop-mediated isothermal AMPlification" (LAMP), and a colorimetric detection method using the metal indicator hydroxynaphtol blue (HBN) which allows to determine an optical signal with a simple readout (with the naked eye). Moreover, we present two approaches for minimizing the assay volume using a stationary microchip LAMP and droplet digital-based LAMP (ddLAMP) as promising highly sensitive setups.


Assuntos
Legionella pneumophila/isolamento & purificação , Legionella/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Colorimetria , Primers do DNA/genética , Naftalenossulfonatos/metabolismo , Sensibilidade e Especificidade , Temperatura
3.
Sensors (Basel) ; 19(20)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614861

RESUMO

Pollen studies play a critical role in various fields of science. In the last couple of decades, replacement of manual identification of pollen by image-based methods using pollen morphological features was a great leap forward, but challenges for pollen with similar morphology remain, and additional approaches are required. Spectroscopy approaches for identification of pollen, such as Raman spectroscopy has potential benefits over traditional methods, due to the investigation of the intrinsic molecular composition of a sample. However, current Raman-based characterization of pollen is complex and time-consuming, resulting in low throughput and limiting the statistical significance of the acquired data. Previously demonstrated high-throughput screening Raman spectroscopy (HTS-RS) eliminates the complexity as well as human interaction by incorporation full automation of the data acquisition process. Here, we present a customization of HTS-RS for pollen identification, enabling sampling of a large number of pollen in comparison to other state-of-the-art Raman pollen investigations. We show that using Raman spectra we are able to provide a preliminary estimation of pollen types based on growth habits using hierarchical cluster analysis (HCA) as well as good taxonomy of 37 different Pollen using principal component analysis-support vector machine (PCA-SVM) with good accuracy even for the pollen specimens sharing similar morphological features. Our results suggest that HTS-RS platform meets the demands for automated pollen detection making it an alternative method for research concerning pollen.

4.
Histopathology ; 72(3): 449-459, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28851100

RESUMO

AIMS: Programmed death ligand 1 (PD-L1) immunohistochemistry has become a mandatory diagnostic test in the treatment of lung cancer. Several research initiatives have started to harmonise the five PD-L1 immunohistochemistry assays that have been used in clinical trials. Here, we report data on interlaboratory and interassay concordance for commercial assays ('assays') and laboratory-developed tests (LDTs) at 10 German testing sites. METHODS AND RESULTS: To assess interlaboratory concordance, a tissue microarray containing 21 pulmonary carcinoma specimens was centrally prepared. Pre-cut sections were stained at 10 sites by the use of assays 28-8, 22C3, SP263, and SP142, as well as 11 LDTs. Assay performance was evaluated with a second tissue microarray containing 11 cell lines with defined PD-L1 expression. Quality control was centrally performed by manual and digital analyses. The assays yielded reproducible IHC staining patterns at all sites. In agreement with previous studies, 22C3, 28-8 and SP263 showed similar staining patterns, whereas SP142 was distinct. Among the LDTs, six of 11 protocols showed staining patterns similar to those of assays 22C3 and 28-8. Interlaboratory concordance of tumour cell scoring by use of a six-step system was moderate (Light's κ = 0.43-0.69), whereas the clinically approved cut-offs of ≥1% and ≥50% showed substantial concordance (κ = 0.73-0.89). Immune cell scoring by the use of SP142 yielded moderate concordance (κ = 0.42). CONCLUSIONS: The data confirm the previously described staining patterns of the assays, and show that they can be reproducibly employed at different sites. LDTs with staining results similar to those of the assays are implementable, but have to be carefully validated.


Assuntos
Antígeno B7-H1/análise , Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Imuno-Histoquímica/normas , Neoplasias Pulmonares/diagnóstico , Humanos , Reprodutibilidade dos Testes
5.
Anal Bioanal Chem ; 410(3): 999-1006, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28905087

RESUMO

A new approach is presented for cell lysate identification which uses SERS-active silver nanoparticles and a droplet-based microfluidic chip. Eighty-nanoliter droplets are generated by injecting silver nanoparticles, KCl as aggregation agent, and cell lysate containing cell constituents, such as nucleic acids, carbohydrates, metabolites, and proteins into a continuous flow of mineral oil. This platform enables accurate mixing of small volumes inside the meandering channels of the quartz chip and allows acquisition of thousands of SERS spectra with 785 nm excitation at an integration time of 1 s. Preparation of three batches of three leukemia cell lines demonstrated the experimental reproducibility. The main advantage of a high number of reproducible spectra is to apply statistics for large sample populations with robust classification results. A support vector machine with leave-one-batch-out cross-validation classified SERS spectra with sensitivities, specificities, and accuracies better than 99% to differentiate Jurkat, THP-1, and MONO-MAC-6 leukemia cell lysates. This approach is compared with previous published reports about Raman spectroscopy for leukemia detection, and an outlook is given for transfer to single cells. A quartz chip was designed for SERS at 785 nm excitation. Principal component analysis of SERS spectra clearly separates cell lysates using variations in band intensity ratios.


Assuntos
Leucemia/diagnóstico , Técnicas Analíticas Microfluídicas/instrumentação , Análise Espectral Raman/instrumentação , Linhagem Celular Tumoral , Desenho de Equipamento , Humanos , Nanopartículas Metálicas/química , Técnicas Analíticas Microfluídicas/métodos , Prata/química , Sonicação , Análise Espectral Raman/métodos
6.
Sensors (Basel) ; 18(2)2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29415468

RESUMO

Due to a worldwide increased use of pharmaceuticals and, in particular, antibiotics, a growing number of these substance residues now contaminate natural water resources and drinking supplies. This triggers a considerable demand for low-cost, high-sensitivity methods for monitoring water quality. Since many biological substances exhibit strong and characteristic absorption features at wavelengths shorter than 300 nm, UV spectroscopy presents a suitable approach for the quantitative identification of such water-contaminating species. However, current UV spectroscopic devices often show limited light-matter interaction lengths, demand sophisticated and bulky experimental infrastructure which is not compatible with microfluidics, and leave large fractions of the sample analyte unused. Here, we introduce the concept of UV spectroscopy in liquid-filled anti-resonant hollow core fibers, with large core diameters and lengths of approximately 1 m, as a means to overcome such limitations. This extended light-matter interaction length principally improves the concentration detection limit by two orders of magnitude while using almost the entire sample volume-that is three orders of magnitude smaller compared to cuvette based approaches. By integrating the fibers into an optofluidic chip environment and operating within the lowest experimentally feasible transmission band, concentrations of the application-relevant pharmaceutical substances, sulfamethoxazole (SMX) and sodium salicylate (SS), were detectable down to 0.1 µM (26 ppb) and 0.4 µM (64 ppb), respectively, with the potential to reach significantly lower detection limits for further device integration.


Assuntos
Espectrofotometria Ultravioleta , Limite de Detecção , Microfluídica , Água
7.
Mod Pathol ; 28(12): 1528-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26403781

RESUMO

Recently the American Society of Clinical Oncology and the College of American Pathologists have updated their clinical practice guidelines for HER2 testing in breast cancer. In order to evaluate these new recommendations, we have re-assessed the HER2 status of 6018 breast cancer cases of the screening population for the HERceptin adjuvant (HERA) trial that were originally centrally tested by fluorescence in situ hybridization based on the FDA-released test guidelines. According to the most recent 2013 ASCO/CAP recommendations, 3380 (56.2%) cases were classified as HER2 positive compared with 3359 (55.8%) applying the HERA/FDA scheme and 3339 (55.5%) applying the 2007 ASCO/CAP guidelines. Twenty-one cases switched from negative (HERA/FDA scheme) to positive (2013 ASCO/CAP guidelines). This group is characterized by a mean HER2 gene copy number of ≥6.0, polysomy or co-amplification of CEP17 with an average CEP17 count of 5, and with HER2 receptor overexpression in 75% of cases. On the basis of the HER2 gene copy number alone, we observe 494 cases (8.2%) that are in the equivocal range. Most of these cases (>80%) were also nondecisive by immunohistochemistry (score 2+) irrespective of whether ratio was <2.0>. The number of equivocal cases that would require HER2 reflex testing decreases to 113 (1.9%) if in addition to the HER2 gene copy number also the ratio of HER2 and CEP17 copy numbers is considered via dual-color in situ hybridization. The combination of applying the HER2 mean gene copy number as well as the HER2/CEP17 ratio to define equivocal test decisions by fluorescence in situ hybridization as proposed by the current ASCO/CAP guidelines appears to be a more optimum approach to adopt in order to avoid or minimize reporting of false negative results. Using the mean HER2 gene copy number alone for decision making results in a significant increase of equivocal cases.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/genética , Hibridização in Situ Fluorescente/métodos , Guias de Prática Clínica como Assunto , Receptor ErbB-2/análise , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Trastuzumab/uso terapêutico
8.
Bioorg Med Chem ; 22(18): 5110-6, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24530033

RESUMO

Natural products represent compound classes with high chemical and structural diversity and various biological activities. Libraries based on natural products are valuable starting point in the search for novel biologically active substances. Here we report on the identification of the natural product podoverine A from the plant Podophyllum versipelle Hance as a novel tubulin-acting agent. A natural product compound collection was subjected to a high-content screen that monitors changes in cytoskeleton and DNA and podoverine A was identified as inhibitor of mitosis. This natural product causes mitotic arrest and inhibits microtubule polymerization in vitro and in cells by targeting the vinca binding site on tubulin.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Flavonas/farmacologia , Microtúbulos/efeitos dos fármacos , Podophyllum/química , Moduladores de Tubulina/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Flavonas/química , Flavonas/isolamento & purificação , Células HeLa , Humanos , Células MCF-7 , Microtúbulos/metabolismo , Estrutura Molecular , Polimerização/efeitos dos fármacos , Relação Estrutura-Atividade , Moduladores de Tubulina/química , Moduladores de Tubulina/isolamento & purificação
9.
J Travel Med ; 31(3)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38206875

RESUMO

BACKGROUND: PfSPZ vaccines comprising Plasmodium falciparum (Pf) sporozoites (SPZ) have demonstrated > 90% protection against variant Pf malaria infections for at least 12 weeks; they are the only vaccines with the level of efficacy necessary to protect travellers. PfSPZ are eukaryotic cells stabilized by cryopreservation and distributed using a cryogenic (below -150 °C) cold chain. The Ebola vaccine and mRNA vaccines against SARS-CoV-2 pioneered uptake of vaccines requiring non-standard ultra-low temperature cold chains. The cryogenic cold chain using liquid nitrogen (LN2) vapour phase (LNVP) cryoshippers, is simpler, more efficient than -80, -20 or 2-8 °C cold chains, and does not use electricity. This study was conducted to evaluate implementation and integration of a cryogenically distributed vaccine at travel and military immunization clinics. METHODS: We conducted sequential 28-day studies evaluating vaccine shipping, storage, maintenance and accession at two US military and two civilian travel health/immunization clinics. In each clinic, personnel were trained in equipment use, procurement and handling of LN2, temperature monitoring and inventory record keeping by in-person or video instruction. RESULTS: Sites required 2-4 h/person for two persons to assimilate and develop the expertise to manage vaccine storage and LNVP operations. LN2 for recharging cryoshippers was delivered every 1-2 weeks. Vaccine ordering, receipt, storage and inventory control was conducted effectively. Simulated single dose vaccine cryovial retrieval and thawing were performed successfully in different travel clinic settings. Continuous temperature monitoring at each site was maintained with only one short excursion above -150 °C (-145 °C) through shipping, use and reverse logistics. Staff, during and at study conclusion, provided feedback that has been incorporated into our models for cold chain logistics. CONCLUSIONS: These studies demonstrated that the training in delivery, storage, administration and integration of PfSPZ vaccines can be successfully managed in different immunization clinic settings for travellers and military personnel.


Assuntos
Vacinas contra Ebola , Doença pelo Vírus Ebola , Malária Falciparum , Medicina Militar , Humanos , Refrigeração , Vacinas contra COVID-19 , Malária Falciparum/prevenção & controle , Plasmodium falciparum
10.
Anal Bioanal Chem ; 405(8): 2743-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23371531

RESUMO

Three important technical innovations are reported here towards Raman-activated cell sorting. Firstly, a microfluidic chip made of quartz is introduced which integrates injection of single cells, trapping by laser fibres and sorting of cells. Secondly, a chip holder was designed to provide simple, accurate and stable adjustment of chips, microfluidic connections and the trapping laser fibres. The new setup enables to the collection of Raman spectra of single cells at 785 nm excitation with 10 s exposure time. Lastly, a new type of modelling the various background contributions is described, improving Raman-based cell identification by the classification algorithm linear discriminant analysis. Mean sensitivity and specificity determined by iterated 10-fold cross validation were 96 and 99 %, respectively, for the distinction of leucocytes extracted from blood, breast cancer cells BT-20 and MCF-7, and leukaemia cells OCI-AML3.


Assuntos
Células/química , Microfluídica/métodos , Análise Espectral Raman/métodos , Linhagem Celular Tumoral , Humanos , Microfluídica/instrumentação , Pinças Ópticas , Quartzo , Análise Espectral Raman/instrumentação
11.
J Hand Surg Am ; 38(5): 999-1005, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23618456

RESUMO

Arthrodesis of a painful and destroyed wrist is one of the key operations in patients with rheumatoid arthritis. Clayton is given credit for the first description of an operative technique of wrist arthrodesis by means of an intramedullary Steinmann pin. Mannerfelt popularized this technique by using a Rush pin and additional fixation with staples. The aim of the present article is to give a detailed description of the operative technique used in our hospital. Over a period of 13 years, 104 modified Clayton-Mannerfelt arthrodeses were performed in 87 patients with rheumatoid arthritis. Ninety-three wrists were reviewed clinically and radiographically. The patients had high fusion rates and a reliable reduction in preoperative pain, with a low rate of complications. The pin technique is more versatile than standard wrist arthrodesis plates, and the wrist can be positioned according to the needs of the patient. This technique seems to be a good alternative to conventional wrist arthrodesis using an arthrodesis plate in wrists destroyed by rheumatoid arthritis, even in situations with difficult bone stock. In most cases, it is not necessary to remove the hardware.


Assuntos
Artrite Reumatoide/cirurgia , Artrodese/métodos , Articulação do Punho/cirurgia , Adulto , Idoso , Ossos do Carpo/cirurgia , Feminino , Humanos , Cápsula Articular/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Técnicas de Sutura
12.
Micromachines (Basel) ; 13(2)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35208362

RESUMO

In the development and optimization of biotechnological cultivation processes the continuous monitoring through the acquisition and interpretation of spectral and morphological properties of bioparticles are challenging. There is therefore a need for the parallel acquisition and interpretation of spatially and spectrally resolved measurements with which particles can be characterized and classified in-flow with high throughput. Therefore, in this paper we investigated the scientific and technological connectivity of standard imaging flow cytometry (IFC) with filter-on-chip based spatially and spectrally resolving snapshot-mosaic cameras for photonic sensing and control in a smart and innovative microfluidic device. For the investigations presented here we used the microalgae Haematococcus pluvialis (HP). These microalgae are used commercially to produce the antioxidant keto-carotenoid astaxanthin. Therefore, HP is relevant to practically demonstrate the usability of the developed system for Multispectral Imaging Flow Cytometry (MIFC) platform. The extension of standard IFC with snapshot-mosaic cameras and multivariate data processing is an innovative approach for the in-flow characterization and derived classification of bioparticles. Finally, the multispectral data acquisition and the therefore developed methodology is generalizable and enables further applications far beyond the here characterized population of HP cells.

13.
Micromachines (Basel) ; 13(7)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35888839

RESUMO

Droplet-based microfluidic screening techniques can benefit from interfacing established microtiter plate-based screening and sample management workflows. Interfacing tools are required both for loading preconfigured microtiter-plate (MTP)-based sample collections into droplets and for dispensing the used droplets samples back into MTPs for subsequent storage or further processing. Here, we present a collection of Digital Microfluidic Pipetting Tips (DMPTs) with integrated facilities for droplet generation and manipulation together with a robotic system for its operation. This combination serves as a bidirectional sampling interface for sample transfer from wells into droplets (w2d) and vice versa droplets into wells (d2w). The DMPT were designed to fit into 96-deep-well MTPs and prepared from glass by means of microsystems technology. The aspirated samples are converted into the channel-confined droplets' sequences separated by an immiscible carrier medium. To comply with the demands of dose-response assays, up to three additional assay compound solutions can be added to the sample droplets. To enable different procedural assay protocols, four different DMPT variants were made. In this way, droplet series with gradually changing composition can be generated for, e.g., 2D screening purposes. The developed DMPT and their common fluidic connector are described here. To handle the opposite transfer d2w, a robotic transfer system was set up and is described briefly.

14.
Anal Methods ; 14(2): 135-146, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34918017

RESUMO

To date, hepatitis B virus (HBV) capsid assembly modulators (CAMs), which target the viral core protein and induce the formation of non-functional viral capsids, have been identified and characterized in microtiter plate-based biochemical or cell-based in vitro assays. In this work, we developed an automated microfluidic screening assay, which uses convection-dominated Taylor-Aris dispersion to generate high-resolution dose-response curves, enabling the measurements of compound EC50 values at very short incubation times. The measurement of early kinetics down to 7.7 seconds in the microfluidic format was utilized to discriminate between the two different classes of CAMs known so far. The CAM (-N), leading to the formation of morphologically normal capsids and the CAM (-A), leading to aberrant HBV capsid structures. CAM-A compounds like BAY 41-4109 and GLS4 showed rapid kinetics, with assembly rates above 80% of the core protein after only a 7 second exposure to the compound, whereas CAM-N compounds like ABI-H0731 and JNJ-56136379 showed significantly slower kinetics. Using our microfluidic system, we characterized two of our in-house screening compounds. Interestingly, one compound showed a CAM-N/A intermediate behavior, which was verified with two standard methods for CAM classification, size exclusion chromatography, and anti-HBc immunofluorescence microscopy. With this proof-of-concept study, we believe that this microfluidic system is a robust primary screening tool for HBV CAM drug discovery, especially for the hit finding and hit-to-lead optimization phases. In addition to EC50 values, this system gives valuable first information about the mode of action of novel CAM screening compounds.


Assuntos
Capsídeo , Vírus da Hepatite B , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Capsídeo/metabolismo , Vírus da Hepatite B/metabolismo , Microfluídica , Compostos Orgânicos
15.
Anal Bioanal Chem ; 400(9): 2755-61, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21359568

RESUMO

In this contribution, the great potential of surface enhanced Raman spectroscopy (SERS) in a lab-on-a-chip (LOC) device for the detection of analyte molecules in a complex environment is demonstrated. Using LOC-SERS, the enzyme activity of thiopurine S-methyltransferase (TPMT) is analysed and identified in lysed red blood cells. The conversion of 6-mercaptopurine to 6-methylmercaptopurine catalysed by TPMT is observed as it gives evidence for the enzyme activity. Being able to determine the TPMT activity before starting a treatment using 6-mercaptopurine, an optimized dosage can be applied to each patient and serious toxicity appearing within thiopurine treatment will be prevented.


Assuntos
Eritrócitos/enzimologia , Dispositivos Lab-On-A-Chip , Metiltransferases/metabolismo , Análise Espectral Raman/métodos , Humanos , Mercaptopurina/análogos & derivados , Mercaptopurina/metabolismo
16.
Lab Chip ; 21(19): 3655-3666, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34514484

RESUMO

Within the last decades, conventional flow cytometry (FC) has evolved as a powerful measurement method in clinical diagnostics, biology, life sciences and healthcare. Imaging flow cytometry (IFC) extends the power of traditional FC by adding high resolution optical and spectroscopic information. However, the conventional IFC only provides a 2D projection of a 3D object. To overcome this limitation, tomographic imaging flow cytometry (tIFC) was developed to access 3D information about the target particles. The goal of tIFC is to visualize surfaces and internal structures in a holistic way. This review article gives an overview of the past and current developments in tIFC.


Assuntos
Imageamento Tridimensional , Citometria de Fluxo
17.
J Cancer Res Clin Oncol ; 147(4): 1271-1272, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33507360

RESUMO

The authors of this "Letter to the Editors" express their major concern about selective and biased reporting in this paper.


Assuntos
Braquiterapia , Neoplasias da Próstata , Humanos , Masculino , Prostatectomia
18.
PLoS One ; 16(3): e0249192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33780476

RESUMO

Label-free and gentle separation of cell stages with desired target properties from mixed stage populations are a major research task in modern biotechnological cultivation process and optimization of micro algae. The reported microfluidic sorter system (MSS) allows the subsequent investigation of separated subpopulations. The implementation of a viability preserving MSS is shown for separation of late stage 1 Haematococcus pluvialis (HP) cells form a mixed stage population. The MSS combines a three-step flow focusing unit for aligning the cells in single file transportation mode at the center of the microfluidic channel with a pure hydrodynamic sorter structure for cell sorting. Lateral displacement of the cells into one of the two outlet channels is generated by piezo-actuated pump chambers. In-line decision making for sorting is based on a user-definable set of image features and properties. The reported MSS significantly increased the purity of target cells in the sorted population (94%) in comparison to the initial mixed stage population (19%).


Assuntos
Separação Celular/instrumentação , Clorofíceas/citologia , Dispositivos Lab-On-A-Chip
19.
Cancer Med ; 10(19): 6807-6822, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34546000

RESUMO

Rocaglates are natural compounds that have been extensively studied for their ability to inhibit translation initiation. Rocaglates represent promising drug candidates for tumor treatment due to their growth-inhibitory effects on neoplastic cells. In contrast to natural rocaglates, synthetic analogues of rocaglates have been less comprehensively characterized, but were also shown to have similar effects on the process of protein translation. Here, we demonstrate an enhanced growth-inhibitory effect of synthetic rocaglates when combined with glucose anti-metabolite 2-deoxy-D-glucose (2DG) in different cancer cell lines. Moreover, we unravel a new aspect in the mechanism of action of synthetic rocaglates involving reduction of glucose uptake mediated by downregulation or abrogation of glucose transporter GLUT-1 expression. Importantly, cells with genetically induced resistance to synthetic rocaglates showed substantially less pronounced treatment effect on glucose metabolism and did not demonstrate GLUT-1 downregulation, pointing at the crucial role of this mechanism for the anti-tumor activity of the synthetic rocaglates. Transcriptome profiling revealed glycolysis as one of the major pathways differentially regulated in sensitive and resistant cells. Analysis of synthetic rocaglate efficacy in a 3D tissue context with a co-culture of tumor and normal cells demonstrated a selective effect on tumor cells and substantiated the mechanistic observations obtained in cancer cell lines. Increased glucose uptake and metabolism is a universal feature across different tumor types. Therefore, targeting this feature by synthetic rocaglates could represent a promising direction for exploitation of rocaglates in novel anti-tumor therapies.


Assuntos
Benzofuranos/uso terapêutico , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Neoplasias/tratamento farmacológico , Benzofuranos/farmacologia , Proliferação de Células , Humanos
20.
Small ; 6(22): 2584-9, 2010 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-20957761

RESUMO

Plasmonic nanoparticles with spectral properties in the UV-to-near-IR range have a large potential for the development of innovative optical devices. Similarly, microstructured optical fibers (MOFs) represent a promising platform technology for fully integrated, next-generation plasmonic devices; therefore, the combination of MOFs and plasmonic nanoparticles would open the way for novel applications, especially in sensing applications. In this Full Paper, a cost-effective, innovative nanoparticle layer deposition (NLD) technique is demonstrated for the preparation of well-defined plasmonic layers of selected particles inside the channels of MOFs. This dynamic chemical deposition method utilizes a combination of microfluidics and self-assembled monolayer (SAM) techniques, leading to a longitudinal homogeneous particle density as long as several meters. By using particles with predefined plasmonic properties, such as the resonance wavelength, fibers with particle-adequate spectral characteristics can be prepared. The application of such fibers for refractive-index sensing yields a sensitivity of about 78 nm per refractive index unit (RIU). These novel, plasmonically tuned optical fibers with freely selected, application-tailored optical properties present extensive possibilities for applications in localized surface plasmon resonance (LSPR) sensing.


Assuntos
Nanopartículas Metálicas/química , Nanotecnologia/métodos , Fibras Ópticas , Ressonância de Plasmônio de Superfície
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