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1.
Rapid Commun Mass Spectrom ; 38(13): e9757, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38693722

RESUMEN

RATIONALE: Contamination of everyday goods with heavy metals such as nickel, cadmium, and lead known to be hazardous to the health of customers is an ongoing problem. METHOD: Here, a mass spectrometric screening method based on reactive desorption electrospray ionization (DESI) is presented for the analysis of metals in consumer goods such as jewelry, tableware, and paintings. The method detects oxidized species of lead, nickel, cadmium, copper, and iron from the surface of objects without sample preparation. Positively charged metal ions form singly and doubly negatively charged complexes with ethylenediaminetetraacetic acid added to the DESI solvent, which are analyzed by a mass spectrometer. RESULTS: Qualitative and quantitative performance of the method was elucidated with metal salt standards. Subsequently, authentic samples were analyzed qualitatively. Reactive DESI-MS was able to detect lead and cadmium in eight out of nine consumer goods. For tableware, these heavy metals were found to be localized in the print as determined by reactive DESI imaging. In addition, mockup paintings generated from modern and historical pigments of Pb, Cu, Cd, and Fe in various media (acrylic binder, egg tempera, and linseed oil) were measured to show the suitability of the method for art authentication and conservation. CONCLUSION: The developed method expands the range of analytes accessible by DESI-MS to metal ions. Hence, DESI becomes a suitable ionization technique for an increasing number of analyte classes, which are of interest in chemical screening of consumer goods.

2.
BMC Med Ethics ; 24(1): 68, 2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37641094

RESUMEN

BACKGROUND: The significance of medical implants goes beyond technical functioning and reaches into everyday life, with consequences for individuals as well as society. Ethical aspects associated with the everyday use of implants are relevant for individuals' lifeworlds and need to be considered in implant care and in the course of technical developments. METHODS: This scoping review aimed to provide a synthesis of the existing evidence regarding ethically relevant psychosocial and cultural aspects in cochlear, glaucoma and cardiovascular implants in patient-centered empirical research. Systematic literature searches were conducted in EBSCOhost, Philpapers, PsycNET, Pubmed, Web of Science and BELIT databases. Eligible studies were articles in German or English language published since 2000 dealing with ethically relevant aspects of cochlear, glaucoma and passive cardiovascular implants based on empirical findings from the perspective of (prospective) implant-wearers and their significant others. Following a descriptive-analytical approach, a data extraction form was developed and relevant data were extracted accordingly. We combined a basic numerical analysis of study characteristics with a thematically organized narrative synthesis of the data. RESULTS: Sixty-nine studies were included in the present analysis. Fifty were in the field of cochlear implants, sixteen in the field of passive cardiovascular implants and three in the field of glaucoma implants. Implant-related aspects were mainly found in connection with autonomy, freedom, identity, participation and justice, whereas little to no data was found with regards to ethical principles of privacy, safety or sustainability. CONCLUSIONS: Empirical research on ethical aspects of implant use in everyday life is highly relevant, but marked by ambiguity and unclarity in the operationalization of ethical terms and contextualization. A transparent orientation framework for the exploration and acknowledgment of ethical aspects in "lived experiences" may contribute to the improvement of individual care, healthcare programs and research quality in this area. Ethics-sensitive care requires creating awareness for cultural and identity-related issues, promoting health literacy to strengthen patient autonomy as well as adjusting healthcare programs accordingly. More consideration needs to be given to sustainability issues in implant development and care according to an approach of ethics-by-design.


Asunto(s)
Glaucoma , Humanos , Estudios Prospectivos , Bases de Datos Factuales , Investigación Empírica , Atención Dirigida al Paciente
3.
Pflugers Arch ; 474(2): 231-242, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34797426

RESUMEN

The distribution of atherosclerotic lesions in the aorta and its branches of ApoE knockout (ApoE-/-) mice is like that of patients with atherosclerosis. By using high-resolution MALDI mass spectrometry imaging (MSI), we aimed at characterizing universally applicable physiological biomarkers by comparing the murine lipid marker profile with that of human atherosclerotic arteries. Therefore, the aorta or carotid artery of male ApoE-/- mice at different ages, human arteries with documented atherosclerotic changes originated from amputated limbs, and corresponding controls were analysed. Obtained data were subjected to multivariate statistical analysis to identify potential biomarkers. Thirty-one m/z values corresponding to individual lipid species of cholesterol esters, lysophosphatidylcholines, lysophosphatidylethanolamines, and cholesterol derivatives were found to be specific in aortic atherosclerotic plaques of old ApoE-/- mice. The lipid composition at related vessel positions of young ApoE-/- mice was more comparable with wild-type mice. Twenty-six m/z values of the murine lipid markers were found in human atherosclerotic peripheral arteries but also control vessels and showed a more patient-dependent diverse distribution. Extensive data analysis without marker preselection based on mouse data revealed lysophosphatidylcholine and glucosylated cholesterol species, the latter not being detected in the murine atherosclerotic tissue, as specific potential novel human atherosclerotic vessel markers. Despite the heterogeneous lipid profile of atherosclerotic peripheral arteries derived from human patients, we identified lipids specifically colocalized to atherosclerotic human tissue and plaques in ApoE-/- mice. These data highlight species-dependent differences in lipid profiles between peripheral artery disease and aortic atherosclerosis.


Asunto(s)
Lípidos/fisiología , Placa Aterosclerótica/metabolismo , Animales , Aorta/metabolismo , Enfermedades de la Aorta/metabolismo , Apolipoproteínas E/metabolismo , Aterosclerosis/metabolismo , Colesterol/metabolismo , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
4.
Analyst ; 146(9): 3004-3015, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33949361

RESUMEN

We present a handheld liquid extraction pen (LEP) combined with a self-sustaining electrospray ionization platform for ambient mass spectrometry within a laboratory-independent workspace. The LEP enables direct sampling from various surfaces and textures, independent of sample shape without precise sample positioning or dedicated sample preparation. The combination of liquid extraction of analytes through the pen and electrospray ionization (ESI) opens a broad field of applications. Qualitative and semi-quantitative analysis is presented for pesticides, plasticizers and drugs which were analyzed from representative consumer goods, such as fruits, toys and pills. Food authentication via metabolomic fingerprinting and multivariate statistics is demonstrated for the analysis of fish fillets and coffee. The LEP source uses a rechargeable battery to power a compressor. Ambient air is used for solvent nebulization in ESI. Through a pressure pump with integrated solvent reservoir, a solvent flow through the LEP and ESI source is generated. Measurement times of more than three hours are possible. The ion source is adaptable to any kind of mass spectrometer equipped with an atmospheric pressure interface. Measurements were performed on orbital trapping instruments and on a miniature mass spectrometer. Coupled to the miniaturized mass spectrometer, the completely portable LEP-MS instrument has dimensions of 48.4 × 27.0 × 18.0 cm (l × w × h).

5.
Analyst ; 145(16): 5584-5593, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32628233

RESUMEN

A general-purpose desorption electrospray ionization (DESI) source is presented which is not bound to the laboratory site. It allows autarkic operation for a few hours and can be connected to different types of (autarkic or non-autarkic) mass spectrometers via an atmospheric-pressure interface. Technical characteristics are described as well as results from direct surface analysis of consumer goods such as plastics, fruit peels or pills, or from living objects such as human skin, demonstrating the detection of various target compounds such as plasticizers, pesticides, drugs or sun blockers. Quantitative analysis is demonstrated for phthalates in plastics. The geometry of the sample, the sample table and the sprayer were modified and characterized for optimization of the method. The autarkic ion source has a total size of 48.4 × 27.0 × 18.0 cm (l×w×h) and a total mass of 7 kg. The source delivers 5.5 bar pressurized air and an adjustable solvent flow rate down to 1.5 µl min-1 for the DESI sprayer. A rechargeable 25.6 V battery allows autarkic runtimes of more than 3.5 hours. Source optimization and characterization was done on an orbital trapping mass spectrometer. Connected to a portable mass spectrometer, the developed device makes DESI suitable for on-site analyses in e.g. consumer protection, border control or homeland security.

6.
J Immunol ; 198(6): 2414-2425, 2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28179495

RESUMEN

Peroxisomes are proposed to play an important role in the regulation of systemic inflammation; however, the functional role of these organelles in inflammatory responses of myeloid immune cells is largely unknown. In this article, we demonstrate that the nonclassical peroxisome proliferator 4-phenyl butyric acid is an efficient inducer of peroxisomes in various models of murine macrophages, such as primary alveolar and peritoneal macrophages and the macrophage cell line RAW264.7, but not in primary bone marrow-derived macrophages. Further, proliferation of peroxisomes blocked the TLR4 ligand LPS-induced proinflammatory response, as detected by the reduced induction of the proinflammatory protein cyclooxygenase (COX)-2 and the proinflammatory cytokines TNF-α, IL-6, and IL-12. In contrast, disturbing peroxisome function by knockdown of peroxisomal gene Pex14 or Mfp2 markedly increased the LPS-dependent upregulation of the proinflammatory proteins COX-2 and TNF-α. Specifically, induction of peroxisomes did not affect the upregulation of COX-2 at the mRNA level, but it reduced the half-life of COX-2 protein, which was restored by COX-2 enzyme inhibitors but not by proteasomal and lysosomal inhibitors. Liquid chromatography-tandem mass spectrometry analysis revealed that various anti-inflammatory lipid mediators (e.g., docosahexaenoic acid) were increased in the conditioned medium from peroxisome-induced macrophages, which blocked LPS-induced COX-2 upregulation in naive RAW264.7 cells and human primary peripheral blood-derived macrophages. Importantly, LPS itself induced peroxisomes that correlated with the regulation of COX-2 during the late phase of LPS activation in macrophages. In conclusion, our findings identify a previously unidentified role for peroxisomes in macrophage inflammatory responses and suggest that peroxisomes are involved in the physiological cessation of macrophage activation.


Asunto(s)
Activación de Macrófagos , Macrófagos/inmunología , Peroxisomas/inmunología , Fenilbutiratos/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , Ácidos Docosahexaenoicos/metabolismo , Técnicas de Silenciamiento del Gen , Humanos , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/inmunología , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Proteína-2 Multifuncional Peroxisomal/genética , Cultivo Primario de Células , Células RAW 264.7 , Proteínas Represoras/genética
7.
Analyst ; 143(18): 4273-4282, 2018 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-30027181

RESUMEN

Macrophages are large phagocytes playing a crucial role in the development and progression of atherosclerosis. The phenotypic polarization and activation of macrophages in atherosclerotic plaques depends on their complex micro-environment and at the same time has a major impact on the vulnerability or stability of advanced atherosclerotic lesions. Many in vitro and in vivo studies have been designed to define markers for macrophage subtypes to better understand the mechanism of plaque progression but they have rather added to the confusion. Nonetheless, some of the in vitro defined macrophage subtypes, like the pro-inflammatory M1 or the anti-inflammatory M2a/b/c macrophage, have been shown to be present in atherosclerotic plaques. Herein, we developed a comprehensive workflow to distinguish between human in vitro differentiated pro-inflammatory M1 and anti-inflammatory M2a and M2c macrophages. The cells were analyzed using qPCR and FACS analyses for defining suitable markers on the transcript (mRNA) and protein level as well as MALDI MSI for the assignment of metabolic markers, which can be used for the identification of the corresponding macrophage subtypes in atherosclerotic plaques. Data obtained using both qPCR and FACS analyses were in agreement with the literature. For the analysis of the macrophages with MALDI MSI, a comprehensive workflow was developed and the obtained data were subjected to different statistical analysis methods like principal component analysis (PCA) to define markers for each macrophage type. Our MALDI MSI results revealed that the method produces reliable and reproducible results but that the heterogeneity of the monocytes derived from different donors is too high to define universal markers on the metabolic level. Moreover, the results show that a sample set of three biological replicates is not sufficient to obtain representative data and therefore we recommend performing ring experiments in which the samples are measured by different laboratories.


Asunto(s)
Diferenciación Celular , Macrófagos/citología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Antiinflamatorios , Biomarcadores , Células Cultivadas , Humanos , Monocitos/citología , Placa Aterosclerótica/inmunología
8.
Anal Chem ; 89(20): 10717-10725, 2017 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-28892367

RESUMEN

Food adulteration is a threat to public health and the economy. In order to determine food adulteration efficiently, rapid and easy-to-use on-site analytical methods are needed. In this study, a miniaturized mass spectrometer in combination with three ambient ionization methods was used for food authentication. The chemical fingerprints of three milk types, five fish species, and two coffee types were measured using electrospray ionization, desorption electrospray ionization, and low temperature plasma ionization. Minimum sample preparation was needed for the analysis of liquid and solid food samples. Mass spectrometric data was processed using the laboratory-built software MS food classifier, which allows for the definition of specific food profiles from reference data sets using multivariate statistical methods and the subsequent classification of unknown data. Applicability of the obtained mass spectrometric fingerprints for food authentication was evaluated using different data processing methods, leave-10%-out cross-validation, and real-time classification of new data. Classification accuracy of 100% was achieved for the differentiation of milk types and fish species, and a classification accuracy of 96.4% was achieved for coffee types in cross-validation experiments. Measurement of two milk mixtures yielded correct classification of >94%. For real-time classification, the accuracies were comparable. Functionality of the software program and its performance is described. Processing time for a reference data set and a newly acquired spectrum was found to be 12 s and 2 s, respectively. These proof-of-principle experiments show that the combination of a miniaturized mass spectrometer, ambient ionization, and statistical analysis is suitable for on-site real-time food authentication.


Asunto(s)
Contaminación de Alimentos/análisis , Leche/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Algoritmos , Animales , Bovinos , Café/química , Cabras , Miniaturización , Análisis de Componente Principal , Alimentos Marinos/análisis , Glycine max/metabolismo
9.
Anal Bioanal Chem ; 409(8): 2107-2117, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28035435

RESUMEN

Direct analysis of fruit and vegetable surfaces is an important tool for in situ detection of food contaminants such as pesticides. We tested three different ways to prepare samples for the qualitative desorption electrospray ionization mass spectrometry (DESI-MS) analysis of 32 pesticides found on nine authentic fruits collected from food control. Best recovery rates for topically applied pesticides (88%) were found by analyzing the surface of a glass slide which had been rubbed against the surface of the food. Pesticide concentration in all samples was at or below the maximum residue level allowed. In addition to the high sensitivity of the method for qualitative analysis, quantitative or, at least, semi-quantitative information is needed in food control. We developed a DESI-MS method for the simultaneous determination of linear calibration curves of multiple pesticides of the same chemical class using normalization to one internal standard (ISTD). The method was first optimized for food extracts and subsequently evaluated for the quantification of pesticides in three authentic food extracts. Next, pesticides and the ISTD were applied directly onto food surfaces, and the corresponding calibration curves were obtained. The determination of linear calibration curves was still feasible, as demonstrated for three different food surfaces. This proof-of-principle method was used to simultaneously quantify two pesticides on an authentic sample, showing that the method developed could serve as a fast and simple preselective tool for disclosure of pesticide regulation violations. Graphical Abstract Multiple pesticide residues were detected and quantified in-situ from an authentic set of food items and extracts in a proof of principle study.


Asunto(s)
Contaminación de Alimentos/análisis , Plaguicidas/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Estándares de Referencia
10.
Altern Ther Health Med ; 23(2): 28-34, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28323626

RESUMEN

Context • In the folk medicine of Mediterranean countries and in ancient Ayurveda, Punica granatum seeds (ie, pomegranate seeds) have been used for treatment of various disorders, including those that nowadays are classified as menopausal symptoms (MSs). Pomegranate seed oil (PSO) from those seeds mainly contains unsaturated fatty acids such as γ-linoleic acid and linolenic acid, but it also includes phytoestrogens. It is, therefore, regarded as a promising option for treating MSs today. Objectives • The study intended to investigate the safety and effectiveness of PSO as a defined P granatum seed oil for patients with MSs. Design • The research team designed an individually controlled, investigator-initiated cohort study. Setting • The treatments were performed at 2 institutions: (1) the Center for Complementary Medicine at the University Medical Center Freiburg (Freiburg, Germany); and (2) in the medical practice of H. Fischer (Freiburg, Germany). Participants • Seventy-eight patients, who had a mean duration of MSs of 46 mo, participated in the study. Intervention • After 4 wk without treatment, which functioned as a period providing an individual control, each participant took 1000 mg of PSO daily in 2 capsules for 8 wk. Outcome Measures • The symptom severity was scored on the German version of the menopausal rating scale (MRS) at baseline, after 4 wk without treatment, after 4 wk of treatment, and postintervention, with 0 = absence of symptoms and 4 = very strong symptoms. The efficacy and tolerability were estimated on scales from 0-4. Each participant's 17ß estradiol was determined at baseline and after postintervention using the patient's sera. The content of the ß-sitosterol was determined in the PSO preparations by gas chromatography. Results • The content of ß-sitosterol in the PSO used in the study was 6.3 mg/1000 mg. In the intention to treat analysis, most MRS symptoms were significantly and relevantly reduced (eg, hot flushes changed from 2.32 ± 1.04 to 1.41 ± 1.07, P < .001). Remarkably, urogenital tract symptoms (ie, a dry vagina) also significantly improved, moving from 1.32 ± 1.43 to 0.85 ± 1.19, P < .001. Few patients reported gastrointestinal symptoms. The tolerability was excellent at 3.69 ± 0.71 after 4 wk of treatment and 3.71 ± 0.65 after 8 wk of treatment. The 17ß estradiol was unchanged. Conclusions • Participants showed significant improvements in all domains of the MRS, remarkably including the difficult-to-treat urogenital symptoms. No changes occurred in the 17ß-estradiol in patients' sera after the PSO treatment. The results are promising and encourage the investigation of PSO rich in ß-sitosterol for treatment of MSs in placebo-controlled studies.


Asunto(s)
Sofocos/tratamiento farmacológico , Lythraceae/química , Menopausia/efectos de los fármacos , Extractos Vegetales/farmacología , Aceites de Plantas/administración & dosificación , Semillas/química , Estudios de Cohortes , Estradiol , Femenino , Humanos , Aceites de Plantas/farmacología , Resultado del Tratamiento , Salud de la Mujer
11.
Analyst ; 140(10): 3484-91, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25827613

RESUMEN

Phthalates are used as plasticizes in many everyday items, but some of them are known as hormone disruptors, being especially harmful during childhood. The European Union therefore restricted their application in children's toys and certain food packaging to 0.1%w. Due to the ever increasing number of plastic-containing consumer goods, rapid screening methods are needed to ensure and improve consumer safety in the future. In this study we evaluated the performance of desorption electrospray ionization (DESI) mass spectrometry (MS) for rapid quantitative screening of phthalates in toys. DESI allowed for direct surface sampling of the toys under atmospheric conditions with minimal sample preparation, while the high performance mass spectrometer used provided a high sensitivity and reliable identification via accurate mass measurements, high mass resolving power and MS/MS capabilities. External calibration curves for six banned phthalates (DBP, BBP, DEHP, DNOP, DINP and DIDP) were obtained from matrix-matched reference materials. Coefficients of determination were greater than 0.985, LOQs ranged from 0.02%w (DIDP) to 2.26%w (DINP) and the relative standard deviation of the calibration curve slope was less than 7.8% for intraday and 11.4% for interday comparison. The phthalate contents of eleven authentic samples were determined in a proof-of-concept approach using DESI MS and results were compared to those from confirmatory methods. The phthalate content was correctly assigned with relative deviations ranging from -20% to +10% for the majority of samples. Given further optimization and automation, DESI MS is likely to become a useful tool for rapid and accurate phthalate screening in the future.


Asunto(s)
Contaminantes Ambientales/análisis , Ácidos Ftálicos/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Seguridad de Productos para el Consumidor , Alimentos , Límite de Detección , Reproducibilidad de los Resultados
12.
Anal Bioanal Chem ; 407(24): 7379-89, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26229027

RESUMEN

Distribution of pesticides both on the surface of leaves and in cross sections of plant stem and leaves was investigated using desorption electrospray ionization mass spectrometry imaging (DESI-MSI) with a spatial resolution of 50-100 µm. Two commercially available insecticide sprays containing different contact pesticides were applied onto leaves of Cotoneaster horizontalis, and the distributions of all active ingredients were directly analyzed. The first spray contained pyrethrins and rapeseed oil, both known as natural insecticides. Each component showed an inhomogeneous spreading throughout the leaf, based on substance polarity and solubility. The second spray contained the synthetic insecticides imidacloprid and methiocarb. Imidacloprid accumulated on the border of the leaf, while methiocarb was distributed more homogenously. In order to investigate the incorporation of a systemically acting pesticide into Kalanchoe blossfeldiana, a commercially available insecticide tablet containing dimethoate was spiked to the soil of the plant. Cross sections of the stem and leaf were obtained 25 and 60 days after application. Dimethoate was mainly detected in the transport system of the plant after 25 days, while it was found to be homogenously distributed in a leaf section after 60 days.


Asunto(s)
Espectrometría de Masas/métodos , Plaguicidas/análisis , Hojas de la Planta/química
13.
J Biol Chem ; 288(2): 1385-96, 2013 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-23168408

RESUMEN

The vacuolar H(+)-ATPase (V-ATPase), a multisubunit proton pump, has come into focus as an attractive target in cancer invasion. However, little is known about the role of V-ATPase in cell death, and especially the underlying mechanisms remain mostly unknown. We used the myxobacterial macrolide archazolid B, a potent inhibitor of the V-ATPase, as an experimental drug as well as a chemical tool to decipher V-ATPase-related cell death signaling. We found that archazolid induced apoptosis in highly invasive tumor cells at nanomolar concentrations which was executed by the mitochondrial pathway. Prior to apoptosis induction archazolid led to the activation of a cellular stress response including activation of the hypoxia-inducible factor-1α (HIF1α) and autophagy. Autophagy, which was demonstrated by degradation of p62 or fusion of autophagosomes with lysosomes, was induced at low concentrations of archazolid that not yet increase pH in lysosomes. HIF1α was induced due to energy stress shown by a decline of the ATP level and followed by a shutdown of energy-consuming processes. As silencing HIF1α increases apoptosis, the cellular stress response was suggested to be a survival mechanism. We conclude that archazolid leads to energy stress which activates adaptive mechanisms like autophagy mediated by HIF1α and finally leads to apoptosis. We propose V-ATPase as a promising drugable target in cancer therapy caught up at the interplay of apoptosis, autophagy, and cellular/metabolic stress.


Asunto(s)
Muerte Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , Autofagia , Línea Celular Tumoral , Proliferación Celular , Citocromos c/metabolismo , Humanos , Potencial de la Membrana Mitocondrial , Microscopía Confocal , Transducción de Señal
14.
Biochim Biophys Acta ; 1828(9): 2121-33, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23685124

RESUMEN

The cell-toxic bile salt glycochenodeoxycholic acid (GCDCA) and taurochenodeoxycholic acid (TCDCA) are responsible for hepatocyte demise in cholestatic liver diseases, while tauroursodeoxycholic acid (TUDCA) is regarded hepatoprotective. We demonstrate the direct mitochondrio-toxicity of bile salts which deplete the mitochondrial membrane potential and induce the mitochondrial permeability transition (MPT). The bile salt mediated mechanistic mode of destruction significantly differs from that of calcium, the prototype MPT inducer. Cell-toxic bile salts initially bind to the mitochondrial outer membrane. Subsequently, the structure of the inner boundary membrane disintegrates. And it is only thereafter that the MPT is induced. This progressive destruction occurs in a dose- and time-dependent way. We demonstrate that GCDCA and TCDCA, but not TUDCA, preferentially permeabilize liposomes containing the mitochondrial membrane protein ANT, a process resembling the MPT induction in whole mitochondria. This suggests that ANT is one decisive target for toxic bile salts. To our knowledge this is the first report unraveling the consecutive steps leading to mitochondrial destruction by cell-toxic bile salts.


Asunto(s)
Ácido Glicoquenodesoxicólico/toxicidad , Mitocondrias Hepáticas/efectos de los fármacos , Translocasas Mitocondriales de ADP y ATP/agonistas , Ácido Tauroquenodesoxicólico/farmacología , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Liposomas/química , Hígado/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias Cardíacas/química , Mitocondrias Hepáticas/metabolismo , Mitocondrias Hepáticas/patología , Translocasas Mitocondriales de ADP y ATP/aislamiento & purificación , Proteínas de Transporte de Membrana Mitocondrial/agonistas , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Membranas Mitocondriales/química , Membranas Mitocondriales/efectos de los fármacos , Poro de Transición de la Permeabilidad Mitocondrial , Miocardio/química , Ratas , Ácido Tauroquenodesoxicólico/toxicidad , Canales Aniónicos Dependientes del Voltaje/química , Canales Aniónicos Dependientes del Voltaje/aislamiento & purificación
15.
Anal Biochem ; 443(1): 66-74, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23969012

RESUMEN

Mitochondrial dysfunctions decisively contribute to the progression of human diseases, implying that functional tests of isolated mitochondria may furnish conclusive information for diagnosis and therapy. Classical mitochondrial isolation methods, however, lack precisely adjustable settings for cell rupture, which is the most critical step in this procedure, and this complicates subsequent analyses. Here, we present an efficient method to isolate functionally active, intact mitochondria from cultured or primary cells and minute tissue samples in a rapid, highly reproducible manner.


Asunto(s)
Hepatocitos/ultraestructura , Mitocondrias Hepáticas/ultraestructura , Neuronas/ultraestructura , Animales , Automatización de Laboratorios , Biomarcadores/metabolismo , Fraccionamiento Celular , Línea Celular Tumoral , Hepatocitos/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Mitocondrias Hepáticas/metabolismo , Neuronas/metabolismo , Cultivo Primario de Células , Ratas , Ratas Endogámicas BUF , Ratas Endogámicas WKY
16.
Telemed J E Health ; 19(6): 460-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23570275

RESUMEN

OBJECTIVE: Implantable cardioverter-defibrillators (ICDs) alone or combined with cardiac resynchronization therapy (CRT-Ds) featuring automatic home monitoring (HM) function can be monitored remotely on a daily basis. Different ways of implementing HM into clinical routines are possible, with efficient patient management being the main objective. In this study, a concept using a telemedical service center (TmSC) to manage HM data was developed and investigated regarding patients' satisfaction, physicians' satisfaction, and alert filtering. SUBJECTS AND METHODS: Fifty-five ICD or CRT-D patients with symptomatic heart failure were enrolled. The TmSC received HM data, identified "actionable parameters" (APs) by following protocol-defined procedures, conducted structured patient interviews, and forwarded selected APs to the respective follow-up clinic. Satisfaction of patients and physicians with the TmSC was evaluated at the end of the study by purpose-designed questionnaires. RESULTS: During a mean follow-up of 402±200 days, 3,831 APs were identified and analyzed at the TmSC (5.28 per patient-month). Most APs were triggered by a pilot detection algorithm for worsening heart failure (2.80 per patient-month), followed by atrial tachyarrhythmia episodes (1.10 per patient-month) and ventricular pacing issues (0.87 per patient-month). The TmSC forwarded 682 APs (18% of all APs) to 10 study sites. Approximately 65% of physicians and patients deemed the TmSC improved patient care. CONCLUSIONS: The TmSC-based management concept was well accepted and appreciated by the majority of physicians and patients. It may be helpful in gaining symptomatic information on top of automatic HM data and in supporting smaller clinics in the follow-up of their device patients.


Asunto(s)
Desfibriladores Implantables , Gestión de la Información en Salud , Insuficiencia Cardíaca/terapia , Centros de Información , Monitoreo Fisiológico/métodos , Telemetría , Anciano , Congresos como Asunto , Comportamiento del Consumidor , Diagnóstico Precoz , Femenino , Alemania , Humanos , Masculino , Proyectos Piloto
17.
Artículo en Inglés | MEDLINE | ID: mdl-37510590

RESUMEN

In the process of developing and implementing innovative implant technologies the consideration of patient preferences can be beneficial for patients, doctors and developers. Nevertheless, in existing literature, there is still scarce knowledge of patients' perspectives on long-term implant care. In this study, three discrete choice experiments (DCEs) were conducted in the context of cochlear implants (CI, n = 92), glaucoma implants (GI, n = 21) and cardiovascular implants (CVI, n = 23), examining the relative importance of attributes of long-term implant care from the patients' perspective. The participants chose between differently shaped options for implant-related care. The attributes of these care options were generated and selected based on previous literature reviews, group discussions and a diary study with patients. The choice data were analyzed via binary logit regression. In CI-DCE, the technological compatibility of the implant with newer implant models, accessories or devices from other manufacturers was highly valued by participants, whereas in GI-DCE the (in)dependency on glaucoma medication post-implantation had the greatest influence on participants' choice behavior. In CVI-DCE, the attribute with the highest relative importance related to the means of securing long-term treatment success. In all three DCE, shared decision making was relatively important for participants. Our results emphasized the importance of an adequate transfer of technological advancements in implant care for promoting patient benefits, such as the availability of comprehensible, understandable, high-quality information about current developments. Similarly, promoting technological health literacy and further pushing the technological compatibility, durability and safety of implants are directions for future implant development in accordance with patients' preferences. Therefore, the participation of implant wearers in the development process is encouraged.


Asunto(s)
Enfermedades Cardiovasculares , Médicos , Humanos , Conducta de Elección , Enfermedades Cardiovasculares/cirugía , Prioridad del Paciente
18.
Circulation ; 124(25): 2892-902, 2011 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-22144571

RESUMEN

BACKGROUND: Excessive formation of reactive oxygen species contributes to tissue injury and functional deterioration after myocardial ischemia/reperfusion. Especially, mitochondrial reactive oxygen species are capable of opening the mitochondrial permeability transition pore, a harmful event in cardiac ischemia/reperfusion. Thioredoxins are key players in the cardiac defense against oxidative stress. Mutations in the mitochondrial thioredoxin reductase (thioredoxin reductase-2, Txnrd2) gene have been recently identified to cause dilated cardiomyopathy in patients. Here, we investigated whether mitochondrial thioredoxin reductase is protective against myocardial ischemia/reperfusion injury. METHODS AND RESULTS: In mice, α-MHC-restricted Cre-mediated Txnrd2 deficiency, induced by tamoxifen (Txnrd2-/-ic), aggravated systolic dysfunction and cardiomyocyte cell death after ischemia (90 minutes) and reperfusion (24 hours). Txnrd2-/-ic was accompanied by a loss of mitochondrial integrity and function, which was resolved on pretreatment with the reactive oxygen species scavenger N-acetylcysteine and the mitochondrial permeability transition pore blocker cyclosporin A. Likewise, Txnrd2 deletion in embryonic endothelial precursor cells and embryonic stem cell-derived cardiomyocytes, as well as introduction of Txnrd2-shRNA into adult HL-1 cardiomyocytes, increased cell death on hypoxia and reoxygenation, unless N-acetylcysteine was coadministered. CONCLUSIONS: We report that Txnrd2 exerts a crucial function during postischemic reperfusion via thiol regeneration. The efficacy of cyclosporin A in cardiac Txnrd2 deficiency may indicate a role for Txnrd2 in reducing mitochondrial reactive oxygen species, thereby preventing opening of the mitochondrial permeability transition pore.


Asunto(s)
Mitocondrias/enzimología , Daño por Reperfusión Miocárdica/metabolismo , Estrés Oxidativo/fisiología , Compuestos de Sulfhidrilo/metabolismo , Tiorredoxina Reductasa 2/metabolismo , Acetilcisteína/farmacología , Animales , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Células Cultivadas , Ciclosporina/farmacología , Células Madre Embrionarias/citología , Células Endoteliales/citología , Inhibidores Enzimáticos/farmacología , Depuradores de Radicales Libres/farmacología , Regulación Enzimológica de la Expresión Génica/fisiología , Células Madre Hematopoyéticas/citología , Ratones , Ratones Noqueados , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/fisiopatología , Miocitos Cardíacos/citología , Estrés Oxidativo/efectos de los fármacos , Tiorredoxina Reductasa 1/genética , Tiorredoxina Reductasa 1/metabolismo , Tiorredoxina Reductasa 2/genética
19.
Biochem Biophys Res Commun ; 424(4): 758-64, 2012 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-22809502

RESUMEN

PURPOSE: ß-Muricholic acid (ßMCA) is a trihydroxylated bile acid that constitutes the major bile acid in rat and mouse. ßMCA is more hydrophilic than ursodeoxycholic acid and has been evaluated for dissolution of cholesterol gallstones. Since it is unknown if ßMCA has beneficial effects on hepatocyte cell death we determined the effect of tauro-ßMCA (TßMCA) on apoptosis in vitro. METHODS: Human Ntcp-transfected HepG2 cells and primary hepatocytes from rat and mouse were incubated with the proapoptotic glycochenodeoxycholic acid (GCDCA) as well as the free fatty acid palmitate in the absence and presence of TßMCA. Apoptosis was quantified using caspase 3/7-assays and after Hoechst 33342 staining. The mitochondrial membrane potential (MMP) was measured fluorometrically using JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazol-carbocyaniniodide). Immunoblotting was performed against the proapoptotic Bcl-2-protein Bax. RESULTS: In Ntcp-HepG2 cells, GCDCA markedly increased apoptosis after 4h. Co-incubation with TßMCA reduced apoptosis to 49% (p<0.01 vs. GCDCA, each; n=6). While GCDCA (100µmol/L) reduced the MMP to 34% after 6h, combination treatment with TßMCA restored the MMP to control levels at all time points (n=4). TßMCA also restored breakdown of the MMP induced by palmitate. GCDCA induced a translocation of Bax from the cytosol to mitochondria that was inhibited by simultaneous treatment with TßMCA in eqimolar concentrations. CONCLUSIONS: TßMCA restricts hepatocellular apoptosis induced by low micromolar concentrations of GCDCA or palmitate via inhibition of Bax translocation to mitochondria and preservation of the MMP. Thus, further studies are warranted to evaluate a potential use of TßMCA in ameliorating liver injury in cholestasis.


Asunto(s)
Apoptosis/efectos de los fármacos , Citoprotección , Ácido Glicoquenodesoxicólico/antagonistas & inhibidores , Hepatocitos/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ácido Taurocólico/análogos & derivados , Ácidos y Sales Biliares/farmacología , Ácido Glicoquenodesoxicólico/farmacología , Células Hep G2 , Humanos , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Ácido Taurocólico/farmacología , Proteína X Asociada a bcl-2/metabolismo
20.
Artículo en Inglés | MEDLINE | ID: mdl-35742224

RESUMEN

The continuous development of medical implants offers various benefits for persons with chronic conditions but also challenges an individual's, and the healthcare system's, ability to deal with technical innovation. Accessing and understanding new information, navigating healthcare, and appraising the role of the implant in body perceptions and everyday life requires health literacy (HL) of those affected as well as an HL-responsive healthcare system. The interconnectedness of these aspects to ethically relevant values such as health, dependence, responsibility and self-determination reinforces the need to address HL in implant care. Following a qualitative approach, we conducted group discussions and a diary study among wearers of a cochlear, glaucoma or cardiovascular implant (or their parents). Data were analysed using the documentary method and grounded theory. The data reveal the perceptions of implant wearers regarding the implant on (1) the ability to handle technical and ambiguous information; (2) dependence and responsibility within the healthcare system; and (3) the ethical aspects of HL. Knowing more about the experiences and values of implant wearers is highly beneficial to develop HL from an ethical perspective. Respective interventions need to initially address ethically relevant values in counselling processes and implant care.


Asunto(s)
Alfabetización en Salud , Teoría Fundamentada , Alfabetización en Salud/métodos , Autonomía Personal , Estudios Prospectivos
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