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1.
Adv Healthc Mater ; 12(27): e2301194, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37171457

RESUMO

Tumor-derived extracellular vesicles (TEVs) induce the epithelial-to-mesenchymal transition (EMT) in nonmalignant cells to promote invasion and cancer metastasis, representing a novel therapeutic target in a field severely lacking in efficacious antimetastasis treatments. However, scalable technologies that allow continuous, multiparametric monitoring for identifying metastasis inhibitors are absent. Here, the development of a functional phenotypic screening platform based on organic electrochemical transistors (OECTs) for real-time, noninvasive monitoring of TEV-induced EMT and screening of antimetastatic drugs is reported. TEVs derived from the triple-negative breast cancer cell line MDA-MB-231 induce EMT in nonmalignant breast epithelial cells (MCF10A) over a nine-day period, recapitulating a model of invasive ductal carcinoma metastasis. Immunoblot analysis and immunofluorescence imaging confirm the EMT status of TEV-treated cells, while dual optical and electrical readouts of cell phenotype are obtained using OECTs. Further, heparin, a competitive inhibitor of cell surface receptors, is identified as an effective blocker of TEV-induced EMT. Together, these results demonstrate the utility of the platform for TEV-targeted drug discovery, allowing for facile modeling of the transient drug response using electrical measurements, and provide proof of concept that inhibitors of TEV function have potential as antimetastatic drug candidates.


Assuntos
Neoplasias da Mama , Vesículas Extracelulares , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Detecção Precoce de Câncer , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Transição Epitelial-Mesenquimal/genética , Movimento Celular , Melanoma Maligno Cutâneo
2.
Nat Commun ; 14(1): 653, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36746944

RESUMO

The detection of proteins is of central importance to biomolecular analysis and diagnostics. Typical immunosensing assays rely on surface-capture of target molecules, but this constraint can limit specificity, sensitivity, and the ability to obtain information beyond simple concentration measurements. Here we present a surface-free, single-molecule microfluidic sensing platform for direct digital protein biomarker detection in solution, termed digital immunosensor assay (DigitISA). DigitISA is based on microchip electrophoretic separation combined with single-molecule detection and enables absolute number/concentration quantification of proteins in a single, solution-phase step. Applying DigitISA to a range of targets including amyloid aggregates, exosomes, and biomolecular condensates, we demonstrate that the assay provides information beyond stoichiometric interactions, and enables characterization of immunochemistry, binding affinity, and protein biomarker abundance. Taken together, our results suggest a experimental paradigm for the sensing of protein biomarkers, which enables analyses of targets that are challenging to address using conventional immunosensing approaches.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Imunoensaio , Biomarcadores/análise , Amiloide , Microfluídica/métodos
3.
ACS Biomater Sci Eng ; 7(12): 5585-5597, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34802228

RESUMO

Cancer-derived exosomes (cEXOs) facilitate transfer of information between tumor and human primary stromal cells, favoring cancer progression. Although the mechanisms used during this information exchange are still not completely understood, it is known that binding is the initial contact established between cEXOs and cells. Hence, studying binding and finding strategies to block it are of great therapeutic value. However, such studies are challenging for a variety of reasons, including the need for human primary cell culture, the difficulty in decoupling and isolating binding from internalization and cargo delivery, and the lack of techniques to detect these specific interactions. In this work, we created a supported biomimetic stem cell membrane incorporating membrane components from human primary adipose-derived stem cells (ADSCs). We formed the supported membrane on glass and on multielectrode arrays to offer the dual option of optical or electrical detection of cEXO binding to the membrane surface. Using our platform, we show that cEXOs bind to the stem cell membrane and that binding is blocked when an antibody to integrin ß1, a component of ADSC surface, is exposed to the membrane surface prior to cEXOs. To test the biological outcome of blocking this interaction, we first confirm that adding cEXOs to cultured ADSCs leads to the upregulation of vascular endothelial growth factor, a measure of proangiogenic activity. Next, when ADSCs are first blocked with anti-integrin ß1 and then exposed to cEXOs, the upregulation of proangiogenic activity and cell proliferation are significantly reduced. This biomimetic membrane platform is the first cell-free label-free in vitro platform for the recapitulation and study of cEXO binding to human primary stem cells with potential for therapeutic molecule screening as it is compatible with scale-up and multiplexing.


Assuntos
Exossomos , Neoplasias , Biomimética , Humanos , Células-Tronco , Fator A de Crescimento do Endotélio Vascular
4.
ACS Nano ; 15(11): 18142-18152, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34694775

RESUMO

Emerging viruses will continue to be a threat to human health and wellbeing into the foreseeable future. The COVID-19 pandemic revealed the necessity for rapid viral sensing and inhibitor screening in mitigating viral spread and impact. Here, we present a platform that uses a label-free electronic readout as well as a dual capability of optical (fluorescence) readout to sense the ability of a virus to bind and fuse with a host cell membrane, thereby sensing viral entry. This approach introduces a hitherto unseen level of specificity by distinguishing fusion-competent viruses from fusion-incompetent viruses. The ability to discern between competent and incompetent viruses means that this device could also be used for applications beyond detection, such as screening antiviral compounds for their ability to block virus entry mechanisms. Using optical means, we first demonstrate the ability to recapitulate the entry processes of influenza virus using a biomembrane containing the viral receptor that has been functionalized on a transparent organic bioelectronic device. Next, we detect virus membrane fusion, using the same, label-free devices. Using both reconstituted and native cell membranes as materials to functionalize organic bioelectronic devices, configured as electrodes and transistors, we measure changes in membrane properties when virus fusion is triggered by a pH drop, inducing hemagglutinin to undergo a conformational change that leads to membrane fusion.


Assuntos
COVID-19 , Nanopartículas , Vírus , Humanos , Pandemias , Internalização do Vírus
5.
Int J Cardiol Heart Vasc ; 31: 100641, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33088899

RESUMO

BACKGROUND: MitraClip ® (MC) is an established procedure for severe mitral regurgitation (MR) in patients deemed unsuitable for surgery.Right ventricular dysfunction (RVD) is associated with a higher mortality risk. The prognostic accuracy of heart failure risk scores like the Seattle heart failure model (SHFM) and Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) score in pts undergoing MC with or without RVD has not been investigated so far. METHODS: SHFM and MAGGIC score were calculated retrospectively. RVD was determined as tricuspid annular plane systolic excursion (TAPSE) ≤15 mm. Area under receiver operating curves (AUROC) of SHFM and MAGGIC were performed for one-year all-cause mortality after MC. RESULTS: N = 103 pts with MR III° (73 ± 11 years, LVEF 37 ± 17%) underwent MC with a reduction of at least I° MR. One-year mortality was 28.2%.In Kaplan-Meier analysis, one- year mortality was significantly higher in RVD-pts (34.8% vs 2.8%, p = 0.009).Area under the Receiver Operating Characteristic (AUROC) for SHFM and MAGGIC were comparable for both scores (SHFM: 0.704, MAGGIC: 0.692). In pts without RVD, SHFM displayed a higher AUROC and therefore better diagnostic accuracy (SHFM: 0.776; MAGGIC: 0.551, p < 0.05). In pts with RVD, MAGGIC and SHFM displayed comparable AUROCs. CONCLUSION: RVD is an important prognostic marker in pts undergoing MC. SHFM and MAGGIC displayed adequate over-all prognostic power in these pts. Accuracy differed in pts with and without RVD, indicating higher predictive power of the SHFM score in pts without RVD.

6.
Rev Environ Contam Toxicol ; 241: 139-160, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27300012

RESUMO

Application of radioactive elements or radionuclides for anthropogenic use is a widespread phenomenon nowadays. Radionuclides undergo radioactive decays releasing ionizing radiation like gamma ray(s) and/or alpha or beta particles that can displace electrons in the living matter (like in DNA) and disturb its function. Radionuclides are highly hazardous pollutants of considerable impact on the environment, food chain and human health. Cleaning up of the contaminated environment through plants is a promising technology where the rhizosphere may play an important role. Plants belonging to the families of Brassicaceae, Papilionaceae, Caryophyllaceae, Poaceae, and Asteraceae are most important in this respect and offer the largest potential for heavy metal phytoremediation. Plants like Lactuca sativa L., Silybum marianum Gaertn., Centaurea cyanus L., Carthamus tinctorius L., Helianthus annuus and H. tuberosus are also important plants for heavy metal phytoremediation. However, transfer factors (TF) of radionuclide from soil/water to plant ([Radionuclide]plant/[Radionuclide]soil) vary widely in different plants. Rhizosphere, rhizobacteria and varied metal transporters like NRAMP, ZIP families CDF, ATPases (HMAs) family like P1B-ATPases, are involved in the radio-phytoremediation processes. This review will discuss recent advancements and potential application of plants for radionuclide removal from the environment.


Assuntos
Plantas/metabolismo , Poluentes Radioativos/farmacocinética , Biodegradação Ambiental , Disponibilidade Biológica , Transporte Biológico , Poluentes Radioativos do Solo/farmacocinética
7.
J Environ Radioact ; 162-163: 289-299, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27318573

RESUMO

In this study, new data are presented for the iodine isotopes (127I, 129I and their isotopic ratios) and Cesium (137Cs) in water samples of the North Sea and the Baltic Sea in 2005 and 2009. This study supplements and extends the study of Michel et al. (2012). Iodine isotopes were separated from their matrix by using an anion exchange method and were determined by applying ICP-MS and AMS. 137Cs in seawater was determined after cesium ion exchange procedure enrichment by gamma-spectrometry. The concentrations of 127I in seawater of the North and Baltic Sea are fairly constant in each Sea with averages of (44 ± 2) and (21 ± 1) ng g-1, respectively, depending on the salinity. However, large variations of 129I concentrations in these areas were detected, which decreased along the French, Belgian, Dutch, German, and Danish shores. 129I/127I isotope ratios in the Baltic Sea are about 10 times lower than in the North Sea in 2009. The highest isotopic ratios (2.7 × 10-6) was detected in the English Channel east of the nuclear reprocessing plant at Cap de la Hague. The results confirm the result of our early study that the sources of 129I in the North Sea are primarily the nuclear reprocessing facilities at Sellafield (UK) and La Hague (F), and that in the Baltic Sea the inflow of water from North Sea through the Danish Straits dominates the occurrence of 129I. In 2009, the activity concentration of 137Cs was at least 6 times higher in the Baltic Sea (37 Bq m-3) than in the North Sea (5.9 Bq m-3), due to release of 137Cs from sediments in the Baltic Sea, which were contaminated by the Chernobyl accident and - to a minor degree - the atmospheric explosions of atomic bombs. The results are discussed by comparing the results of our previous work and the current study demonstrating the continuing disequilibrium of 129I/127I atomic ratio in the environmental compartments.


Assuntos
Radioisótopos do Iodo/análise , Iodo/análise , Monitoramento de Radiação , Água do Mar/química , Poluentes Radioativos da Água/análise , Países Bálticos , Mar do Norte
8.
J Environ Radioact ; 154: 101-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26867099

RESUMO

New data about (129)I, (127)I concentrations and their isotopic ratios in aerosol samples from the trace survey station of the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Northern Germany, are presented and discussed in this paper. The investigated samples were collected on a weekly basis during the years 2011 to 2013. Iodine was extracted from aerosol filters using a strong basic solution and was separated from the matrix elements with chloroform and was analysed by accelerator mass spectrometry (AMS) for (129)I and by inductively coupled plasma mass spectrometry (ICP-MS) for (127)I. The concentrations of (127)I and (129)I in aerosol filters ranged from 0.31 to 3.71 ng m(-3) and from 0.06 to 0.75 fg m(-3), respectively. The results of (129)I/(127)I isotopic ratios were in the order 10(-8) to 10(-7). The (129)I originated directly from gaseous emissions and indirectly from liquid emissions (via sea spray) from the reprocessing plants in Sellafield and La Hague. In comparison with the results of (131)I after the Fukushima accident, no contribution of (129)I from this accident was detectable in Central Europe due to the high background originating from the (129)I releases of the European reprocessing plants. (129)I atmospheric activity concentrations were compared with those of an anthropogenic radionuclide ((85)Kr). We did not find any correlation between (129)I and (85)Kr, both having nuclear reprocessing plant as the main source.


Assuntos
Aerossóis/análise , Poluentes Radioativos do Ar/análise , Isótopos de Iodo/análise , Radioisótopos do Iodo/análise , Monitoramento de Radiação , Inglaterra , França , Alemanha
9.
Protein Expr Purif ; 120: 42-50, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26687898

RESUMO

N(pro) fusion technology, a highly efficient system for overexpression of proteins and peptides in Escherichia coli, was further developed by splitting the autoprotease N(pro) into two fragments to generate a functional complementation system. The size of the expression tag is thus reduced from 168 to 58 amino acids, so by 66%. Upon complementation of the fragments auto-proteolytic activity is restored. This process has been shown for three model proteins of different size, a short 16 aa-peptide, MCP-1, and lysozyme. Moreover, the complementation was still functional after immobilization of the N-terminal fragment to a solid support which enables recycling of the immobilized fragment. This strategy enhances overall productivity of N(pro) Fusion Technology and thus allows more efficient production of recombinant proteins with reduced costs and in higher yields. Overall, the N(pro) complementation system has, depending on the size of the target molecule, potential to increase the productivity up to 4 fold for batch refolding and even more for on-column refolding strategies by the proven possibility of regeneration of the immobilized fragment.


Assuntos
Escherichia coli/genética , Peptídeo Hidrolases , Proteínas Recombinantes de Fusão/isolamento & purificação , Regulação para Cima , Sequência de Aminoácidos , Quimiocina CCL2/isolamento & purificação , Quimiocina CCL2/metabolismo , Cromatografia de Afinidade , Escherichia coli/metabolismo , Dados de Sequência Molecular , Muramidase/isolamento & purificação , Muramidase/metabolismo , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Redobramento de Proteína , Proteínas Recombinantes de Fusão/metabolismo
10.
Arch Gynecol Obstet ; 293(2): 383-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26193954

RESUMO

PURPOSE: To analyze the trends and developments among journals in the specialty of obstetrics and gynecology. METHODS: Using the Journal Citation Reports from 2007 to 2013, we analyzed the impact factor (IF), Eigenfactor® Score (ES), and Article Influence® Score (AIS) of 43 journals in the field of obstetrics and gynecology published in this time period. RESULTS: From 78 journals of the Journal Citation Report 2013, 43 were selected for this study. The mean IF grew from 1.68 ± 0.97 in 2007 to 2.12 ± 1.05 in 2013, the ES from 0.0113 ± 0.0169 to 0.0114 ± 0.0140, and the AIS from 0.513 ± 0.302 to 0.663 ± 0.359. Differences in the IF, ES, and AIS between journals from the United States versus Europe could be observed. In most cases, the IF, ES, and AIS increased between 2007 and 2013. Strong correlations could be found between IF, AIS, and ES. CONCLUSIONS: The overall mean IF for obstetrical and gynecological journals increased over the analyzed time period. The IF remains the standard measure to compare scientific journals. It correlates well with two major alternative measures of scientific impact, the ES and especially the AIS. Other measures are evolving and might show superior usage in the future.


Assuntos
Ginecologia/tendências , Fator de Impacto de Revistas , Obstetrícia/tendências , Publicações Periódicas como Assunto/estatística & dados numéricos , Editoração/tendências , Bibliometria , Feminino , Humanos , Gravidez , Editoração/estatística & dados numéricos , Estados Unidos
11.
J Environ Radioact ; 144: 21-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25791900

RESUMO

The Mulde River drains the former uranium mining areas in Saxony (Germany), which has led to a large-scale contamination of the river and the adjacent floodplain soils with radionuclides of the uranium decay series. The objective of the investigation is to quantify the long-term effect of former uranium mining activities on a river system. All of the investigated environmental compartments (water, sediment, soil) still reveal an impact from the former uranium mining and milling activities. The contamination of water has decreased considerably during the last 20 years due to the operation of water treatment facilities. The uranium content of the sediments decreased as well (on average by a factor of 5.6), most likely caused by displacement of contaminated material during flood events. Currently, the impact of the mining activities is most obvious in soils. For some of the plots activity concentrations of >200 Bq/kg of soil were detected for uranium-238. Alluvial soils used as grassland were found to be contaminated to a higher degree than those used as cropland.


Assuntos
Mineração , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Urânio/análise , Poluentes Radioativos da Água/análise , Alemanha , Radioisótopos/análise
12.
Int J Cancer ; 136(3): 699-708, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24895230

RESUMO

This phase I study tested the safety, feasibility, pharmacokinetics and pharmacodynamics of cisplatin administered as hyperthermic intraoperative intraperitoneal chemoperfusion (HIPEC) in patients with platinum-sensitive recurrent epithelial ovarian cancer (EOC) undergoing secondary cytoreductive surgery followed by postoperative platinum-based intravenous chemotherapy. Twelve patients with operable, recurrent platinum-sensitive EOC (recurrence ≥6 months after first-line therapy) were included according to the classical 3+3 dose-escalation design at three dose levels-60, 80 and 100 mg/m(2). After surgical cytoreduction, a single dose of cisplatin was administered via HIPEC for 90 min at 41-43°C. Postoperatively, all patients were treated with standard intravenous platinum-based combination chemotherapy. One of six patients experienced a dose-limiting toxicity (grade 3 renal toxicity) at a dose of 100 mg/m(2). The remaining five patients treated with 100 mg/m(2) tolerated their treatment well. The recommended phase II dose was established at 100 mg/m(2). The mean peritoneal-to-plasma AUC ratio was 19·5 at the highest dose level. Cisplatin-induced DNA adducts were confirmed in tumor samples. Common postoperative grade 1-3 toxicities included fatigue, postoperative pain, nausea, and surgical site infection. The ability to administer standard intravenous platinum-based chemotherapy after HIPEC was uncompromised. Cisplatin administered as HIPEC at a dose of 100 mg/m(2) has an acceptable safety profile in selected patients undergoing secondary cytoreductive surgery for platinum-sensitive recurrent EOC. Favorable pharmacokinetic and pharmacodynamic properties of HIPEC with cisplatin were confirmed at all dose levels, especially at 100 mg/m(2). The results are encouraging to determine the efficacy of HIPEC as a complementary treatment in patients with EOC.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Procedimentos Cirúrgicos de Citorredução/métodos , Hipertermia Induzida , Recidiva Local de Neoplasia/terapia , Neoplasias Epiteliais e Glandulares/terapia , Neoplasias Ovarianas/terapia , Adulto , Idoso , Carcinoma Epitelial do Ovário , Cisplatino/efeitos adversos , Cisplatino/análise , Cisplatino/farmacocinética , Terapia Combinada , Adutos de DNA/análise , Feminino , Humanos , Pessoa de Meia-Idade
13.
PLoS One ; 9(8): e105007, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25121606

RESUMO

INTRODUCTION: The increased thrombotic risk of oral contraceptives (OC) has been attributed to various alterations of the hemostatic system, including acquired resistance to activated protein C (APC). To evaluate to what extent OC-associated APC resistance induces a prothrombotic state we monitored plasma levels of thrombin and molecular markers specific for thrombin formation in women starting OC use. Elevated plasma levels of thrombin have been reported to characterize situations of high thrombotic risk such as trauma-induced hypercoagulability, but have not yet been studied during OC use. PATIENTS AND METHODS: Blood samples were collected prospectively from healthy women (n = 21) before and during three menstruation cycles after start of OC. APC resistance was evaluated using a thrombin generation-based assay. Plasma levels of thrombin and APC were directly measured using highly sensitive oligonucleotide-based enzyme capture assay (OECA) technology. Thrombin generation markers and other hemostasis parameters were measured additionally. RESULTS: All women developed APC resistance as indicated by an increased APC sensitivity ratio compared with baseline after start of OC (p = 0.0003). Simultaneously, plasma levels of thrombin, prothrombin fragment 1+2, and of thrombin-antithrombin complexes did not change, ruling out increased thrombin formation. APC plasma levels were also not influenced by OC use, giving further evidence that increased thrombin formation did not occur. CONCLUSIONS: In the majority of OC users no enhanced thrombin formation occurs despite the development of APC resistance. It cannot be ruled out, however, that thrombin formation might occur to a greater extent in the presence of additional risk factors. If this were the case, endogenous thrombin levels might be a potential biomarker candidate to identify women at high thrombotic risk during OC treatment. Large-scale studies are required to assess the value of plasma levels of thrombin as predictors of OC-associated thrombotic risk.


Assuntos
Resistência à Proteína C Ativada/induzido quimicamente , Anticoncepcionais Orais Hormonais/efeitos adversos , Trombose/induzido quimicamente , Adolescente , Adulto , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
14.
J Radiol Prot ; 34(3): 575-93, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24983208

RESUMO

Despite several decades of studies on the risk assessment and risk perception of ionising radiation, risk management of radioactive materials remains a challenging issue. This is also true for wastes containing technologically enhanced naturally occurring radioactive materials. The present work focuses on the underlying reasons for communication problems between experts and affected members of the public. Exploring the case of a German remediation site with residual radioactive contamination in a residential area, the experts' as well as the residents' perspectives were studied by conducting qualitative interviews. Our results indicate a variety of reasons for communication problems on different levels of risk management and risk communication: the regulatory, the communicative and the moral levels. In the observed case, four salient causes for problems in risk communication and risk management emerged: the mismatch in understanding the residents' values, the issue of risk communication in an unforeseen situation, the problem of the regulatory gap between radiation protection and soil protection in regard to legacies with naturally occurring radioactive material in Germany, and the challenge of communicating a highly complex scientific issue to non-scientists. Moreover, one (at least partial) solution could be seen: the introduction of an external mediator. The results indicate that coordination of different health and environment protection disciplines-in this case radiation protection relating to soil protection-is possible and urgently needed. The opportunity to put, at least natural, radioactive material in line with other conventional industrial materials should be taken.


Assuntos
Recuperação e Remediação Ambiental/legislação & jurisprudência , Proteção Radiológica/legislação & jurisprudência , Poluentes Radioativos do Solo , Acesso à Informação , Comunicação , Alemanha , Humanos , Medição de Risco
15.
Thromb Res ; 133(5): 886-91, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24568775

RESUMO

INTRODUCTION: The estrogen antagonist tamoxifen (TAM) increases the thrombotic risk similar to estrogen containing oral contraceptives (OC). In OC users this risk is attributed to alterations of hemostasis resulting in acquired resistance to activated protein C (APC). TAM-induced APC resistance has not been reported yet. MATERIALS AND METHODS: Blood samples were collected prospectively from women with breast cancer before (n=25) and monthly after start of adjuvant TAM treatment (n=75). APC resistance was evaluated on basis of the effect of APC on the endogenous thrombin generation potential. To detect increased in vivo APC generation APC plasma levels were measured using a highly sensitive oligonucleotide-based enzyme capture assay. Routine hemostasis parameters were measured additionally. RESULTS: APC sensitivity decreased by 41% (p=0.001) compared to baseline after one month of TAM application and remained significantly decreased during the study period. Free protein S increased (p=0.008) while other analyzed procoagulant factors, inhibitors, and activation markers of coagulation decreased or did not change significantly. In five patients the APC concentration increased to non-physiological levels but an overall significant increase of APC was not observed. CONCLUSIONS: This is the first study showing acquired APC resistance under TAM therapy. Acquired APC resistance might explain the increased thrombotic risk during TAM treatment. Observed changes of hemostasis parameters suggest different determinants of TAM-induced APC resistance than in OC-induced APC resistance. The presence of acquired APC resistance in TAM patients warrants further evaluation if these patients may benefit from antithrombotic prophylaxis in the presence of additional thrombotic risk factors.


Assuntos
Resistência à Proteína C Ativada/induzido quimicamente , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Proteína C/metabolismo , Proteína C/farmacologia , Tamoxifeno/efeitos adversos , Adulto , Idoso , Antineoplásicos Hormonais/administração & dosagem , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/farmacologia , Tamoxifeno/administração & dosagem
16.
Chemosphere ; 108: 134-44, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24560283

RESUMO

As a nonrenewable resource, phosphorus (P) is the second most important macronutrient for plant growth and nutrition. Demand of phosphorus application in the agricultural production is increasing fast throughout the globe. The bioavailability of phosphorus is distinctively low due to its slow diffusion and high fixation in soils which make phosphorus a key limiting factor for crop production. Applications of phosphorus-based fertilizers improve the soil fertility and agriculture yield but at the same time concerns over a number of factors that lead to environmental damage need to be addressed properly. Phosphate rock mining leads to reallocation and exposure of several heavy metals and radionuclides in crop fields and water bodies throughout the world. Proper management of phosphorus along with its fertilizers is required that may help the maximum utilization by plants and minimum run-off and wastage. Phosphorus solubilizing bacteria along with the root rhizosphere of plant integrated with root morphological and physiological adaptive strategies need to be explored further for utilization of this extremely valuable nonrenewable resource judiciously. The main objective of this review is to assess the role of phosphorus in fertilizers, their uptake along with other elements and signaling during P starvation.


Assuntos
Fertilizantes/análise , Metais Pesados/metabolismo , Fosfatos/metabolismo , Fósforo/metabolismo , Plantas/metabolismo , Poluentes do Solo/metabolismo , Agricultura , Biodegradação Ambiental , Transporte Biológico , Metais Pesados/análise , Metais Pesados/toxicidade , Fosfatos/análise , Fósforo/análise , Rizosfera , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
17.
Acta Anaesthesiol Scand ; 56(8): 1066-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22762373

RESUMO

We report a patient with severe anaphylactic shock immediately after injection of i.v. fluorescein. The patient recovered without sequela. Immunoglobulin E (IgE) mechanism was highly suggestive with significant increase in serum tryptase, positive basophil allergen threshold sensitivity (CD-sens) and histamine release tests towards fluorescein. This is, to our knowledge, the first report where CD-sens has been used to aid in diagnosing an IgE-mediated anaphylactic shock caused by fluorescein.


Assuntos
Anafilaxia/imunologia , Meios de Contraste/efeitos adversos , Fluoresceína/efeitos adversos , Imunoglobulina E/imunologia , Idoso , Anafilaxia/tratamento farmacológico , Anafilaxia/etiologia , Antígenos CD/imunologia , Basófilos/imunologia , Dor no Peito/complicações , Epinefrina/uso terapêutico , Liberação de Histamina/fisiologia , Humanos , Intubação Intratraqueal , Masculino , Muco/fisiologia , Testes Cutâneos , Triptases , Vasoconstritores/uso terapêutico
18.
Rev Sci Instrum ; 83(4): 043105, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22559513

RESUMO

Since its inauguration in 2005, the INE-Beamline for actinide research at the synchrotron source ANKA (KIT North Campus) provides dedicated instrumentation for x-ray spectroscopic characterization of actinide samples and other radioactive materials. R&D work at the beamline focuses on various aspects of nuclear waste disposal within INE's mission to provide the scientific basis for assessing long-term safety of a final nuclear waste repository. The INE-Beamline is accessible for the actinide and radiochemistry community through the ANKA proposal system and the European Union Integrated Infrastructure Initiative ACTINET-I3. Experiments with activities up to 1 × 10(+6) times the European exemption limit are feasible within a safe but flexible containment concept. Measurements with monochromatic radiation are performed at photon energies varying between ~2.1 keV (P K-edge) and ~25 keV (Pd K-edge), including the lanthanide L-edges and the actinide M- and L3-edges up to Cf. The close proximity of the INE-Beamline to INE controlled area labs offers infrastructure unique in Europe for the spectroscopic and microscopic characterization of actinide samples. The modular beamline design enables sufficient flexibility to adapt sample environments and detection systems to many scientific questions. The well-established bulk techniques x-ray absorption fine structure (XAFS) spectroscopy in transmission and fluorescence mode have been augmented by advanced methods using a microfocused beam, including (confocal) XAFS/x-ray fluorescence detection and a combination of (micro-)XAFS and (micro-)x-ray diffraction. Additional instrumentation for high energy-resolution x-ray emission spectroscopy has been successfully developed and tested.

19.
Rapid Commun Mass Spectrom ; 26(6): 583-91, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22328210

RESUMO

Polymerization in hexavalent uranium solutions was measured by electrospray ionization time-of-flight mass spectrometry in three different acidic media at pH values from 3 to 5.3 in order to detect all hydrolysis species present in solution. The aqueous solutions were directly measured without further dilution in organic solvents. At high uranyl concentrations ([U(VI)] = 10(- 3) M) artifacts were observed due to the presence of more than one solution species per formed microdroplet. Those artifacts were composed of ions and neutral species being present in the same droplet. However, by analyzing the detected species carefully, the origin of the artifacts could be traced back to the physically meaningful species. Still, only general trends of the hydrolysis behavior can be deduced from the measurements at [U(VI)] = 1 ⋅ 10(- 3) M. The solutions at [U(VI)] = 5 ⋅ 10(- 5) M did not show any comparable artifact formation. The detected species distributions resemble the expected trends calculated from the equilibrium constants published in the Nuclear Energy Agency Thermodynamic Database (NEA-TDB). The neutral (UO(2))(CO(3))(0) species present in solution causes, if located in the same microdroplet as a charged species, the apparent formation of dimeric and trimeric ternary hydroxo carbonate complexes at pH 5.3. As the uncharged species is not repelled from the ionic species, it might remain in the same droplet during the droplet fission process. By dividing those detected species into the uncharged (UO(2))(CO(3))(0) and a second ionic species, the relative abundances of the solution species can be corrected, leading to a good agreement with the predictions of the published equilibrium constants. In addition to the well-known trimer, we report the direct mass spectrometric detection of the dimeric (UO(2))(2)(OH)(2)(2+) species.

20.
Dtsch Med Wochenschr ; 136(46): 2348-54, 2011 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22068444

RESUMO

BACKGROUND AND OBJECTIVE: It was the aim of this study to measure the effects over two years of daily sport activity during the school-day on their physical fitness (primary endpoint), motor coordination and blood pressure (secondary endpoints). METHODS: A total of 232 children from eleven different 6 (th) grade classes were enrolled after informed parental consent. Their mean age was 11.1 ± 0.6 years. Six classes were randomly assigned for intervention (n=141), five as control (n=91). Those of the intervention cohort undertook, for five days weekly during the school year one hour of regulated sport exercise, including 15 min of endurance training. The pupils of the control group undertook customary sport activity (two hours a week). Anthropometric data were recorded and maximal oxygen uptake measured in each pupil, as well as blood pressure and motor coordination at the beginning and at the end of each of the two years of the study. The data were analyzed using the cluster randomization method. RESULTS: Maximal oxygen uptake (VO (2)max) had improved among the intervention group after two years, compared with the controls (3.12 m/kg/min, 95% confindence interval [CI] 0.06-6.19), while improvement in motor coordination just failed to reach statistical significance (3.06, 95% CI -0.17-6.29). There was no significant difference in systolic and diastolic blood pressure, but a downward trend in the prevalence of overweight and obesity from 12.1% to 7.8% in the intervention group. CONCLUSION: The results indicate that daily physical exercise during school hours should be given greater importance. But it will require a long-term trial to determine whether promotion of increased physical activity at school influences the prevalence of cardiovascular risk factors when the pupils reach adulthood.


Assuntos
Exercício Físico/fisiologia , Educação Física e Treinamento/normas , Pressão Sanguínea/fisiologia , Criança , Análise por Conglomerados , Feminino , Alemanha , Frequência Cardíaca/fisiologia , Humanos , Masculino , Sobrepeso/epidemiologia , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia , Prevalência , Resultado do Tratamento
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