RESUMEN
In recent decades, nanopores have become a promising diagnostic tool. Protein and solid-state nanopores are increasingly used for both RNA/DNA sequencing and small molecule detection. The latter is of great importance, as their detection is difficult or expensive using available methods such as HPLC or LC-MS. DNA aptamers are an excellent detection element for sensitive and specific detection of small molecules. Herein, a method for quantifying small molecules using a ready-to-use sequencing platform is described. Taking ethanolamine as an example, a strand displacement assay is developed in which the target-binding aptamer is displaced from the surface of magnetic particles by ethanolamine. Non-displaced aptamer and thus the ethanolamine concentration are detected by the nanopore system and can be quantified in the micromolar range using our in-house developed analysis software. This method is thus the first to describe a label-free approach for the detection of small molecules in a protein nanopore system.
Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanoporos , Etanolamina/análisis , Etanolamina/química , Etanolaminas , ADN/química , Secuencia de Bases , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodosRESUMEN
BACKGROUND: In vivo-mimicking conditions are critical in in vitro cell analysis to obtain clinically relevant results. The required conditions, comparable to those prevalent in nature, can be provided by microfluidic dynamic cell cultures. Microfluidics can be used to fabricate and test the functionality and biocompatibility of newly developed nanosystems or to apply micro- and nanoelectromechanical systems embedded in a microfluidic system. However, the use of microfluidic systems is often hampered by their accessibility, acquisition cost, or customization, especially for scientists whose primary research focus is not microfluidics. RESULTS: Here we present a method for 3D printing that can be applied without special prior knowledge and sophisticated equipment to produce various ready-to-use microfluidic components with a size of 100 µm. Compared to other available methods, 3D printing using fused deposition modeling (FDM) offers several advantages, such as time-reduction and avoidance of sophisticated equipment (e.g., photolithography), as well as excellent biocompatibility and avoidance of toxic, leaching chemicals or post-processing (e.g., stereolithography). We further demonstrate the ease of use of the method for two relevant applications: a cytotoxicity screening system and an osteoblastic differentiation assay. To our knowledge, this is the first time an application including treatment, long-term cell culture and analysis on one chip has been demonstrated in a directly 3D-printed microfluidic chip. CONCLUSION: The direct 3D printing method is tested and validated for various microfluidic components that can be combined on a chip depending on the specific requirements of the experiment. The ease of use and production opens up the potential of microfluidics to a wide range of users, especially in biomedical research. Our demonstration of its use as a cytotoxicity screening system and as an assay for osteoblastic differentiation shows the methods potential in the development of novel biomedical applications. With the presented method, we aim to disseminate microfluidics as a standard method in biomedical research, thus improving the reproducibility and transferability of results to clinical applications.
Asunto(s)
Células Madre Mesenquimatosas , Microfluídica , Impresión Tridimensional , Humanos , Diferenciación Celular , Evaluación Preclínica de Medicamentos , Dispositivos Laboratorio en un Chip , Microfluídica/métodos , Reproducibilidad de los ResultadosRESUMEN
Rash, photosensitivity, erythema multiforme, and the acute generalized exanthematous pustulosis (AGEP) are relatively uncommon adverse reactions of drugs. To date, the etiology is not well understood and individual susceptibility still remains unknown. Amiodarone, chlorpromazine, amitriptyline, and trimipramine are classified lysosomotropic as well as photosensitizing, however, they fail to trigger rash and pruritic papules in all individuals. Lysosomotropism is a common charcteristic of various drugs, but independent of individuals. There is evidence that the individual ability to respond to external oxidative stress is crosslinked with the elongation of long-chain fatty acids to very long-chain fatty acids by ELOVLs. ELOVL6 and ELOVL7 are sensitive to ROS induced depletion of cellular NADPH and insufficient regeneration via the pentose phosphate pathway and mitochondrial fatty acid oxidation. Deficiency of NADPH in presence of lysosomotropic drugs promotes the synthesis of C16-ceramide in lysosomes and may contribute to emerging pruritic papules of AGEP. However, independently from a lysosomomotropic drug, severe depletion of ATP and NAD(P)H, e.g., by UV radiation or a potent photosensitizer can trigger likewise the collapse of the lysosomal transmembrane proton gradient resulting in lysosomal C16-ceramide synthesis and pruritic papules. This kind of papules are equally present in polymorphous light eruption (PMLE/PLE) and acne aestivalis (Mallorca acne). The suggested model of a compartmentalized ceramide metabolism provides a more sophisticated explanation of cutaneous drug adverse effects and the individual sensitivity to UV radiation. Parameters such as pKa and ClogP of the triggering drug, cutaneous fatty acid profile, and ceramide profile enables new concepts in risk assessment and scoring of AGEP as well as prophylaxis outcome.
Asunto(s)
Pustulosis Exantematosa Generalizada Aguda/tratamiento farmacológico , Pustulosis Exantematosa Generalizada Aguda/etiología , Amitriptilina/farmacocinética , Ceramidas/metabolismo , Esfingolípidos/metabolismo , Pustulosis Exantematosa Generalizada Aguda/patología , Vesícula/inducido químicamente , Dermatitis Atópica/etiología , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Antagonistas de los Receptores Histamínicos/efectos adversos , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , NADP/metabolismo , Trastornos por Fotosensibilidad/etiología , Trastornos por Fotosensibilidad/metabolismo , Fármacos Fotosensibilizantes/efectos adversosRESUMEN
Precise and rapid identification and characterization of pathogens and antimicrobial resistance patterns are critical for the adequate treatment of infections, which represent an increasing problem in intensive care medicine. The current situation remains far from satisfactory in terms of turnaround times and overall efficacy. Application of an ineffective antimicrobial agent or the unnecessary use of broad-spectrum antibiotics worsens the patient prognosis and further accelerates the generation of resistant mutants. Here, we provide an overview that includes an evaluation and comparison of existing tools used to diagnose bacterial infections, together with a consideration of the underlying molecular principles and technologies. Special emphasis is placed on emerging developments that may lead to significant improvements in point of care detection and diagnosis of multi-resistant pathogens, and new directions that may be used to guide antibiotic therapy.
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Antibacterianos/uso terapéutico , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/tratamiento farmacológico , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana/métodosRESUMEN
Lysosomotropism is a biological characteristic of small molecules, independently present of their intrinsic pharmacological effects. Lysosomotropic compounds, in general, affect various targets, such as lipid second messengers originating from lysosomal enzymes promoting endothelial stress response in systemic inflammation; inflammatory messengers, such as IL-6; and cathepsin L-dependent viral entry into host cells. This heterogeneous group of drugs and active metabolites comprise various promising candidates with more favorable drug profiles than initially considered (hydroxy) chloroquine in prophylaxis and treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections/Coronavirus disease 2019 (COVID-19) and cytokine release syndrome (CRS) triggered by bacterial or viral infections. In this hypothesis, we discuss the possible relationships among lysosomotropism, enrichment in lysosomes of pulmonary tissue, SARS-CoV-2 infection, and transition to COVID-19. Moreover, we deduce further suitable approved drugs and active metabolites based with a more favorable drug profile on rational eligibility criteria, including readily available over-the-counter (OTC) drugs. Benefits to patients already receiving lysosomotropic drugs for other pre-existing conditions underline their vital clinical relevance in the current SARS-CoV2/COVID-19 pandemic.
Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Descubrimiento de Drogas , Lisosomas/efectos de los fármacos , SARS-CoV-2/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Antivirales/farmacocinética , Antivirales/uso terapéutico , COVID-19/inmunología , COVID-19/metabolismo , COVID-19/virología , Clorpromazina/farmacocinética , Clorpromazina/farmacología , Clorpromazina/uso terapéutico , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Descubrimiento de Drogas/métodos , Reposicionamiento de Medicamentos/métodos , Fluvoxamina/farmacocinética , Fluvoxamina/farmacología , Fluvoxamina/uso terapéutico , Humanos , Hidroxicloroquina/farmacocinética , Hidroxicloroquina/farmacología , Hidroxicloroquina/uso terapéutico , Interleucina-1/antagonistas & inhibidores , Interleucina-1/inmunología , Interleucina-6/antagonistas & inhibidores , Interleucina-6/inmunología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/virología , Lisosomas/inmunología , Lisosomas/metabolismo , Lisosomas/virología , SARS-CoV-2/inmunología , SARS-CoV-2/fisiología , Bibliotecas de Moléculas Pequeñas/farmacocinética , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Replicación Viral/efectos de los fármacosRESUMEN
Life-threatening bacterial infections have been managed by antibiotics for years and have significantly improved the wellbeing and lifetime of humans. However, bacteria have always been one step ahead by inactivating the antimicrobial agent chemically or by producing certain enzymes. The alarming universal occurrence of multidrug-resistant (MDR) bacteria has compelled researchers to find alternative treatments for MDR infections. This is a menace where conventional chemotherapies are no longer promising, but several novel approaches could help. Our current review article discusses the novel approaches that can combat MDR bacteria: starting off with potential nanoparticles (NPs) that efficiently interact with microorganisms causing fatal changes in the morphology and structure of these cells; nanophotothermal therapy using inorganic NPs like AuNPs to destroy pathogenic bacterial cells; bacteriophage therapy against which bacteria develop less resistance; combination drugs that act on dissimilar targets in distinctive pathways; probiotics therapy by the secretion of antibacterial chemicals; blockage of quorum sensing signals stopping bacterial colonization, and vaccination against resistant bacterial strains along with virulence factors. All these techniques show us a promising future in the fight against MDR bacteria, which remains the greatest challenge in public health care.
Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Farmacorresistencia Bacteriana Múltiple , Animales , Antibacterianos/uso terapéutico , Péptidos Catiónicos Antimicrobianos/uso terapéutico , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/terapia , Humanos , Nanopartículas/uso terapéutico , Terapia de Fagos/métodos , Vacunación/métodosRESUMEN
Furan-2-carboxylic acid was used as a starting material for the synthesis of dehydro-homopilopic acid. Esterification, hydrogenation and enzymatic hydrolysis followed by the reduction of Weinreb amides and a single-step attachment of a 1-methyl-imidazole residue allowed for the concise synthesis of both enantiomers of pilocarpine.
Asunto(s)
4-Butirolactona/análogos & derivados , Furanos/química , Pilocarpina/síntesis química , 4-Butirolactona/síntesis química , Amidas/química , Ácidos Carboxílicos/química , Esterificación , Hidrogenación , Hidrólisis , Pilocarpina/química , EstereoisomerismoRESUMEN
Pentacyclic triterpenoids oleanolic acid, ursolic acid, betulinic acid, and platanic acid were acetylated and converted into several amides 9-31; the cytotoxicity of which has been determined in sulforhodamine B assays employing seral human tumor cell lines and nonmalignant fibroblasts. Thereby, a betulinic acid/trans-1,4-cyclohexyldiamine amide showed excellent cytotoxicity (for example, EC50 = 0.6 µM for HT29 colon adenocarcinoma cells).
Asunto(s)
Ciclohexilaminas/química , Triterpenos Pentacíclicos/farmacología , Amidas/química , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Concentración 50 Inhibidora , Ratones , Células 3T3 NIH , Triterpenos Pentacíclicos/químicaRESUMEN
Three novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations of 7 and 11 µM, respectively. The results from docking experiments with EGFR suggested the binding of compound 1 at the ATP binding site of EGFR. Furthermore, the crystal structure of compound 3 (7-(4-bromophenyl)-9-(pyridin-4-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine) was determined by single crystal X-ray analysis. Our work represents a promising starting point for the development of a new series of compounds targeting EGFR.
Asunto(s)
Antineoplásicos/síntesis química , Receptores ErbB/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/síntesis química , Pirimidinas/química , Triazoles/química , Antineoplásicos/farmacología , Sitios de Unión , Proliferación Celular/efectos de los fármacos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Células HeLa , Humanos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
A convenient route has been developed for the synthesis of novel 6-amino-2,2-(or 3,3-difluoro)-2-(or 3),6-dideoxy-hexopyranoses. Biological screening showed these compounds as good inhibitors for several glycosidases. Especially n-propyl 6-amino-2,6-dideoxy-2,2-difluoro-ß-d-glucopyranoside (8) was an excellent competitive inhibitor for the ß-galactosidase from E. coli holding a K i of 0.50 µM.
RESUMEN
Fast point-of-care (POC) diagnostics represent an unmet medical need and include applications such as lateral flow assays (LFAs) for the diagnosis of sepsis and consequences of cytokine storms and for the treatment of COVID-19 and other systemic, inflammatory events not caused by infection. Because of the complex pathophysiology of sepsis, multiple biomarkers must be analyzed to compensate for the low sensitivity and specificity of single biomarker targets. Conventional LFAs, such as gold nanoparticle dyed assays, are limited to approximately five targets-the maximum number of test lines on an assay. To increase the information obtainable from each test line, we combined green and red emitting quantum dots (QDs) as labels for C-reactive protein (CRP) and interleukin-6 (IL-6) antibodies in an optical duplex immunoassay. CdSe-QDs with sharp and tunable emission bands were used to simultaneously quantify CRP and IL-6 in a single test line, by using a single UV-light source and two suitable emission filters for readout through a widely available BioImager device. For image and data processing, a customized software tool, the MultiFlow-Shiny app was used to accelerate and simplify the readout process. The app software provides advanced tools for image processing, including assisted extraction of line intensities, advanced background correction and an easy workflow for creation and handling of experimental data in quantitative LFAs. The results generated with our MultiFlow-Shiny app were superior to those generated with the popular software ImageJ and resulted in lower detection limits. Our assay is applicable for detecting clinically relevant ranges of both target proteins and therefore may serve as a powerful tool for POC diagnosis of inflammation and infectious events.
Asunto(s)
Biomarcadores/análisis , Proteína C-Reactiva/análisis , Inmunoensayo/métodos , Interleucina-6/análisis , Puntos Cuánticos/química , Sepsis/diagnóstico , Anticuerpos/inmunología , Betacoronavirus/aislamiento & purificación , Proteína C-Reactiva/inmunología , COVID-19 , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Humanos , Interleucina-6/inmunología , Límite de Detección , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/virología , Sistemas de Atención de Punto , SARS-CoV-2 , Sepsis/metabolismo , Programas Informáticos , Rayos UltravioletaRESUMEN
In line with SARS and MERS, the SARS-CoV-2/COVID-19 pandemic is one of the largest challenges in medicine and health care worldwide. SARS-CoV-2 infection/COVID-19 provides numerous therapeutic targets, each of them promising, but not leading to the success of therapy to date. Neither an antiviral nor an immunomodulatory therapy in patients with SARS-CoV-2 infection/COVID-19 or pre-exposure prophylaxis against SARS-CoV-2 has proved to be effective. In this review, we try to close the gap and point out the likely relationships among lysosomotropism, increasing lysosomal pH, SARS-CoV-2 infection, and disease process, and we deduce an approach for the treatment and prophylaxis of COVID-19, and cytokine release syndrome (CRS)/cytokine storm triggered by bacteria or viruses. Lysosomotropic compounds affect prominent inflammatory messengers (e.g., IL-1B, CCL4, CCL20, and IL-6), cathepsin-L-dependent viral entry of host cells, and products of lysosomal enzymes that promote endothelial stress response in systemic inflammation. As supported by recent clinical data, patients who have already taken lysosomotropic drugs for other pre-existing conditions likely benefit from this treatment in the COVID-19 pandemic. The early administration of a combination of antivirals such as remdesivir and lysosomotropic drugs, such as the antibiotics teicoplanin or dalbavancin, seems to be able to prevent SARS-CoV-2 infection and transition to COVID-19.
Asunto(s)
Infecciones por Coronavirus/patología , Lisosomas/metabolismo , Neumonía Viral/patología , Enzima Convertidora de Angiotensina 2 , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Betacoronavirus/aislamiento & purificación , Betacoronavirus/fisiología , COVID-19 , Proteasas 3C de Coronavirus , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/virología , Síndrome de Liberación de Citoquinas/etiología , Síndrome de Liberación de Citoquinas/patología , Humanos , Pandemias , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/complicaciones , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/virología , SARS-CoV-2 , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/metabolismo , Internalización del Virus/efectos de los fármacosRESUMEN
An aging population leads to increasing demand for sustained quality of life with the aid of novel implants. Patients expect fast healing and few complications after surgery. Increased biofunctionality and antimicrobial behavior of implants, in combination with supportive stem cell therapy, can meet these expectations. Recent research in the field of bone implants and the implementation of autologous mesenchymal stem cells in the treatment of bone defects is outlined and evaluated in this review. The article highlights several advantages, limitations and advances for metal-, ceramic- and polymer-based implants and discusses the future need for high-throughput screening systems used in the evaluation of novel developed materials and stem cell therapies. Automated cell culture systems, microarray assays or microfluidic devices are required to efficiently analyze the increasing number of new materials and stem cell-assisted therapies. Approaches described in the literature to improve biocompatibility, biofunctionality and stem cell differentiation efficiencies of implants range from the design of drug-laden nanoparticles to chemical modification and the selection of materials that mimic the natural tissue. Combining suitable implants with mesenchymal stem cell treatment promises to shorten healing time and increase treatment success. Most research studies focus on creating antibacterial materials or modifying implants with antibacterial coatings in order to address the increasing number of complications after surgeries that are mostly caused by bacterial infections. Moreover, treatment of multiresistant pathogens will pose even bigger challenges in hospitals in the future, according to the World Health Organization (WHO). These antibacterial materials will help to reduce infections after surgery and the number of antibiotic treatments that contribute to the emergence of new multiresistant pathogens, whilst the antibacterial implants will help reduce the amount of antibiotics used in clinical treatment.
Asunto(s)
Regeneración Ósea , Ensayos Analíticos de Alto Rendimiento/métodos , Células Madre Mesenquimatosas/citología , Trasplante de Células Madre/métodos , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Cicatrización de Heridas , Animales , Antibacterianos/química , Antibacterianos/uso terapéutico , Regeneración Ósea/fisiología , Técnicas de Cultivo de Célula/métodos , Cerámica/química , Cerámica/uso terapéutico , Ensayos Analíticos de Alto Rendimiento/instrumentación , Humanos , Metales/química , Metales/uso terapéutico , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Polímeros/química , Polímeros/uso terapéutico , Andamios del Tejido/microbiología , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiologíaRESUMEN
Assessment of hematotoxicity from environmental or xenobiotic compounds is of notable interest and is frequently assessed via the colony forming unit (CFU) assay. Identification of the mode of action of single compounds is of further interest, as this often enables transfer of results across different tissues and compounds. Metabolomics displays one promising approach for such identification, nevertheless, suitability with current protocols is restricted. Here, we combined a hematopoietic stem and progenitor cell (HSPC) expansion approach with distinct lineage differentiations, resulting in formation of erythrocytes, dendritic cells and neutrophils. We examined the unique combination of pathway activity in glycolysis, glutaminolysis, polyamine synthesis, fatty acid oxidation and synthesis, as well as glycerophospholipid and sphingolipid metabolism. We further assessed their interconnections and essentialness for each lineage formation. By this, we provide further insights into active metabolic pathways during the differentiation of HSPC into different lineages, enabling profound understanding of possible metabolic changes in each lineage caused by exogenous compounds.
Asunto(s)
Linaje de la Célula/fisiología , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/metabolismo , Metaboloma , Células Mieloides/fisiología , Antígenos CD34/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Linaje de la Célula/genética , Células Cultivadas , Perfilación de la Expresión Génica , Células Madre Hematopoyéticas/fisiología , Humanos , Redes y Vías Metabólicas/genética , Metabolómica , RNA-SeqRESUMEN
The combination of the "correct" triterpenoid, the "correct" spacer and rhodamine B (RhoB) seems to be decisive for the ability of the conjugate to accumulate in mitochondria. So far, several triterpenoid rhodamine B conjugates have been prepared and screened for their cytotoxic activity. To obtain cytotoxic compounds with EC50 values in a low nano-molar range combined with good tumor/non-tumor selectivity, the Rho B unit has to be attached via an amine spacer to the terpenoid skeleton. To avoid spirolactamization, secondary amines have to be used. First results indicate that a homopiperazinyl spacer is superior to a piperazinyl spacer. Hybrids derived from maslinic acid or tormentic acid are superior to those from oleanolic, ursolic, glycyrrhetinic or euscaphic acid. Thus, a tormentic acid-derived RhoB conjugate 32, holding a homopiperazinyl spacer can be regarded, at present, as the most promising candidate for further biological studies.
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Rodaminas/química , Triterpenos/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Técnicas de Química Sintética , Humanos , Concentración 50 Inhibidora , Ratones , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Click reactions between alkynes and azides using the privileged scaffold of triterpenes have been of interest for biological chemistry. Many publications deal with the synthesis of novel bioactive molecules; these conjugates have also been used for bioanalytical and diagnostic purposes. As a result, conjugates of better physicochemical properties were obtained; even compounds of improved solubility in water and physiological fluids were made through the introduction of a triazol residue. "Hybrid-structures", i.e. molecules consisting of two independently bioactive subunits linked by a triazole residue were higher bioactive than their parent compounds but not as active as expected, and with a few exceptions the ultimate breakthrough has not yet been achieved. Only in the synthesis of compounds with anti-leishmanial activity some new and promising lead structures were found. As a consequence, triazole modified triterpenes seem to hold their greatest future prospect rather as diagnostic reagents and molecular probes than as drugs.
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Química Clic , Triterpenos/química , Alquinos/química , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Antiprotozoarios/farmacología , Azidas/química , Catálisis , Supervivencia Celular/efectos de los fármacos , Reacción de Cicloadición , Humanos , Triazoles/química , Triterpenos/síntesis química , Triterpenos/farmacologíaRESUMEN
This work describes an aptamer-based capillary assay for ethanolamine (EA). It is making use of strand displacement format and magnetic particles. The capillary tubes are coated with three layers, viz. (a) first with short oligonucleotides complementary to the aptamer (EA-comp.); (b) then with magnetic particles (Dynabeads) coated with EA-binding aptamer (EA-aptamer), and (c) with short oligonucleotide-coated magnetic particles (EA-comp.). On exposure to a sample containing ethanolamine, the DNA-coated magnetic particles are released and subsequently collected and spatially separated using a permanent magnet. This results in the formation of a characteristic black/brown spots. The assay has a visual limit of detection of 5 nM and only requires 5 min of incubation. Quantification is possible through capture and analysis of digital (RGB) photos in the 5 to 75 nM EA concentration range. Furthermore, results from tap water and serum spiked with EA samples showed that the platform performs well in complex samples and can be applied to real sample analysis. The combined use of plastic capillaries, visual detection and passive flow make the method suited for implementation into a point-of-care device. Graphical abstract Schematic representation of the capillary assay steps.
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Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , ADN/química , Etanolamina/sangre , Aptámeros de Nucleótidos/genética , Secuencia de Bases , Técnicas Biosensibles/instrumentación , ADN/genética , Agua Potable/análisis , Etanolamina/química , Humanos , Límite de Detección , Fenómenos Magnéticos , Hibridación de Ácido Nucleico , Pruebas en el Punto de AtenciónRESUMEN
For modern approaches in precision medicine, fast and easy-to-use point-of-care diagnostics (POCs) are essential. Digoxin was chosen as an example of a drug requiring close monitoring. Digoxin is a cardiac glycoside used for the treatment of tachycardia with a narrow therapeutic window of 0.5-2.0 ng·mL-1, and toxic effects are common for concentrations above 2.5 ng·mL-1. For monitoring of blood concentration levels and treatment of intoxication, highly selective antibodies for digoxin and its hapten, digoxigenin, are available. A smartphone readout system is described for measuring digoxigenin in human serum using a common gold nanoparticle lateral flow assay (LFA). The R-package GNSplex, which also includes a Shiny app for quantitative test interpretation based on linear models, is used for image analysis. Images of lateral flow strips were taken with an iPhone camera and a simple darkbox made from black cardboard. Sensitivity and accuracy of the quantitative smartphone system as well as analytical parameters such as limit of detection (LOD) were determined and compared to data obtained with a high resolution BioImager. The data show that the smartphone based digoxin assay yields reliable quantitative results within the clinically relevant concentration range. Graphical abstract For therapeutic drug monitoring and point of care diagnostics we introduce the open source R-package GNSplex for smartphone readout and interpretation of lateral flow assays. The cardiac glycoside dixogin was used as target for this quantitative smartphone reader.
RESUMEN
Active rebuilding, stabilizing, and maintaining the lipid barrier of the skin is an encouraging disease management and care concept for dry skin, atopic dermatitis (eczema, neurodermatitis), and psoriasis. For decades, corticosteroids have been the mainstay of topical therapy for atopic dermatitis; however, innovations within the scope of basic therapy are rare. In (extremely) dry, irritated, or inflammatory skin, as well as in lesions, an altered (sphingo)lipid profile is present. Recovery of a balanced (sphingo)lipid profile is a promising target for topical and personalized treatment and prophylaxis. New approaches for adults and small children are still lacking. With an ingenious combination of commonly used active ingredients, it is possible to restore and reinforce the dermal lipid barrier and maintain refractivity. Lysosomes and ceramide de novo synthesis play a key role in attenuation of the dermal lipid barrier. Linoleic acid in combination with amitriptyline in topical medication offers the possibility to relieve patients affected by dry and itchy skin, mild to moderate atopic dermatitis lesions, and eczemas without the commonly occurring serious adverse effects of topical corticosteroids or systemic antibody administration.
Asunto(s)
Ceramidas/metabolismo , Dermatitis Atópica/metabolismo , Amitriptilina/uso terapéutico , Animales , Antioxidantes/metabolismo , Apoptosis/fisiología , Humanos , Ácido Linoleico/uso terapéutico , Esfingolípidos/metabolismoRESUMEN
We previously developed a single-molecule microscopy method termed TOCCSL (thinning out clusters while conserving stoichiometry of labeling), which allows for direct imaging of stable nanoscopic platforms with raft-like properties diffusing in the plasma membrane. As a consensus raft marker, we chose monomeric GFP linked via a glycosylphosphatidylinositol (GPI) anchor to the cell membrane (mGFP-GPI). With this probe, we previously observed cholesterol-dependent homo-association to nanoplatforms diffusing in the plasma membrane of live CHO cells. Here, we report the release of this homo-association upon addition of 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC) or 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine, two oxidized phospholipids (oxPLs) that are typically present in oxidatively modified low-density lipoprotein. We found a dose-response relationship for mGFP-GPI nanoplatform disintegration upon addition of POVPC, correlating with the signal of the apoptosis marker Annexin V-Cy3. Similar concentrations of lysolipid showed no effect, indicating that the observed phenomena were not linked to properties of the lipid bilayer itself. Inhibition of acid sphingomyelinase by NB-19 before addition of POVPC completely abolished nanoplatform disintegration by oxPLs. In conclusion, we were able to determine how oxidized lipid species disrupt mGFP-GPI nanoplatforms in the plasma membrane. Our results favor an indirect mechanism involving acid sphingomyelinase activity rather than a direct interaction of oxPLs with nanoplatform constituents.