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2.
Sci Total Environ ; 912: 169276, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38086480

ABSTRACT

Marine debris, particularly microdebris (< 1 mm) poses a potential threat to marine life, including reef-building corals. While previous research has mainly focused on the impact of single polymer microplastics, the effects of natural microdebris, composed of a mixture of materials, have not been explored. Therefore, this study aimed to assess the effects of different microdebris, originating from major sources of pollution, on reef-building corals. For this, we exposed two scleractinian coral species, Pocillopora verrucosa and Stylophora pistillata, known to frequently ingest microplastics, to four types of microdebris in an 8-week laboratory experiment: fragmented environmental plastic debris, artificial fibers from clothing, residues from the automobile sector consisting of tire wear, brake abrasion, and varnish flakes, a single polymer microplastic treatment consisting of polyethylene particles, and a microdebris-free control treatment. Specifically, we (I) compared the effects of the different microdebris on coral growth, necrosis, and photosynthesis, (II) investigated the difference between the microdebris mixtures and the exposure to the single polymer treatment, and (III) identified potential mechanisms causing species-specific effects by contrasting the feeding responses of the two coral species on microdebris and natural food. We show that the fibers and tire wear had the strongest effects on coral physiology, with P. verrucosa being more affected than S. pistillata. Both species showed increased volume growth in response to the microdebris treatments, accompanied by decreased calcification in P. verrucosa. Photosynthetic efficiency of the symbionts was enhanced in both species. The species-specific physiological responses might be attributed to feeding reactions, with P. verrucosa responding significantly more often to microdebris than S. pistillata. These findings highlight the effect of different microdebris on coral physiology and the need for future studies to use particle mixtures to better mimic naturally occurring microdebris and assess its effect on corals in more detail.


Subject(s)
Anthozoa , Animals , Anthozoa/physiology , Coral Reefs , Plastics/toxicity , Microplastics , Photosynthesis
3.
Front Oncol ; 13: 1129627, 2023.
Article in English | MEDLINE | ID: mdl-37114125

ABSTRACT

Glioblastoma (GBM) heterogeneity, aggressiveness and infiltrative growth drastically limit success of current standard of care drugs and efficacy of various new therapeutic approaches. There is a need for new therapies and models reflecting the complex biology of these tumors to analyze the molecular mechanisms of tumor formation and resistance, as well as to identify new therapeutic targets. We established and screened a panel of 26 patient-derived subcutaneous (s.c.) xenograft (PDX) GBM models on immunodeficient mice, of which 15 were also established as orthotopic models. Sensitivity toward a drug panel, selected for their different modes of action, was determined. Best treatment responses were observed for standard of care temozolomide, irinotecan and bevacizumab. Matching orthotopic models frequently show reduced sensitivity, as the blood-brain barrier limits crossing of the drugs to the GBM. Molecular characterization of 23 PDX identified all of them as IDH-wt (R132) with frequent mutations in EGFR, TP53, FAT1, and within the PI3K/Akt/mTOR pathway. Their expression profiles resemble proposed molecular GBM subtypes mesenchymal, proneural and classical, with pronounced clustering for gene sets related to angiogenesis and MAPK signaling. Subsequent gene set enrichment analysis identified hallmark gene sets of hypoxia and mTORC1 signaling as enriched in temozolomide resistant PDX. In models sensitive for mTOR inhibitor everolimus, hypoxia-related gene sets reactive oxygen species pathway and angiogenesis were enriched. Our results highlight how our platform of s.c. GBM PDX can reflect the complex, heterogeneous biology of GBM. Combined with transcriptome analyses, it is a valuable tool in identification of molecular signatures correlating with monitored responses. Available matching orthotopic PDX models can be used to assess the impact of the tumor microenvironment and blood-brain barrier on efficacy. Our GBM PDX panel therefore represents a valuable platform for screening regarding molecular markers and pharmacologically active drugs, as well as optimizing delivery of active drugs to the tumor.

4.
Emerg Infect Dis ; 28(12): 2538-2542, 2022 12.
Article in English | MEDLINE | ID: mdl-36418000

ABSTRACT

We collected data on mass mortality in Sandwich terns (Thalasseus sandvicensis) during the 2022 breeding season in the Netherlands. Mortality was associated with at least 2 variants of highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b. We report on carcass removal efforts relative to survival in colonies. Mitigation strategies urgently require structured research.


Subject(s)
Charadriiformes , Influenza A Virus, H5N1 Subtype , Influenza A virus , Influenza in Birds , Influenza, Human , Animals , Humans , Influenza A Virus, H5N1 Subtype/genetics , Influenza in Birds/epidemiology , Netherlands/epidemiology , Influenza, Human/epidemiology
5.
Environ Pollut ; 310: 119861, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-35940480

ABSTRACT

Marine debris is now a ubiquitous component of the Anthropocene global ocean. Plastic ingestion by marine wildlife was first reported in the 1960s and since that time, roughly one thousand marine species have been reported to consume this debris. This study focuses on plastic ingestion by marine invertebrates and vertebrates in the North Pacific Ocean. Specifically, we reviewed the scientific literature to assess the scope of the problem, identified key bioindicator species, and proposed guidelines for future monitoring of plastic debris in North Pacific marine ecosystems. Our meta-analysis confirmed that the North Pacific is among the most polluted ocean regions globally; roughly half of all fish and seabird specimens and more than three-quarters of sea turtles and bivalve specimens examined in this region had consumed plastic. While there are not enough standardized data to assess if these ingestion rates are changing, sampling standardization and reporting of methods are improving over time. Using a rubric-evaluation approach, we evaluated 352 species for their potential to serve as bioindicators of the prevalence of plastic pollution in the North Pacific. This analysis revealed a suite of 12 bioindicator species candidates which sample a variety of ecosystem components and cover a wide range of plastic size classes. Thus, we contend that these bioindicator candidates provide a key foundation for developing a comprehensive plastic monitoring program in the region. To enhance the utility of these bioindicators, we developed a framework for standardized data collection to minimize methodological variability across different studies and to facilitate the assessment of temporal trends over space and time. Tracking plastic ingestion by these bioindicators will help to assess the effectiveness of mitigation actions in the region, a critical step to evaluate progress towards sustainability and improved ocean health in the 21st century.


Subject(s)
Environmental Biomarkers , Plastics , Animals , Eating , Ecosystem , Environmental Monitoring , Pacific Ocean , Sentinel Species , Waste Products
6.
Food Chem Toxicol ; 159: 112701, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34838897

ABSTRACT

Oral exposure to mineral oil may result in a narrow fraction of mineral oil saturated hydrocarbon (MOSH) being retained in tissues. Excess of MOSH hepatic retention may lead to the formation of lipogranuloma caused by predominantly multiring cycloalkanes (naphthenics) in a critical range of C25-C35. Although hepatic lipogranuloma is of low pathological concern, MOSH tissue deposition could be minimized by using an oil of similar quality but devoid of naphthenic structures to decrease hepatic retention. Synthetic Gas to liquid (GTL) oils offer an alternative to petroleum derived mineral oils, because they do not contain naphthenic structures. To demonstrate this point, SD rats were fed either GTL oil (99% iso-alkanes) or naphthenic mineral oil (84% cycloalkanes) at 200 mg/kg bw/day for 90 or 134 days with a recovery group. Liver, fat and mesenteric lymph nodes were analyzed for alkane sub-type levels using Online-HPLC-GC-FID and GCxGC-TOF-MS. Results indicate that at equal external dose, GTL hydrocarbons result in lower tissue levels and more rapid excretion than MOSH. GTL retained hepatic fractions were also qualitatively different than MOSH constituents. Because chemical composition differences, GTL oil show low absorption and tissue retention potential and thus an advantageous alternative to conventional mineral oil.


Subject(s)
Liver , Mineral Oil , Oils , Paraffin , Animals , Cycloparaffins/chemistry , Cycloparaffins/metabolism , Female , Liver/drug effects , Liver/metabolism , Lymph Nodes/metabolism , Mineral Oil/chemistry , Mineral Oil/metabolism , Mineral Oil/pharmacokinetics , Oils/chemistry , Oils/metabolism , Oils/pharmacokinetics , Paraffin/chemistry , Paraffin/metabolism , Paraffin/pharmacokinetics , Rats , Rats, Sprague-Dawley , Tissue Distribution
7.
Toxins (Basel) ; 13(5)2021 05 11.
Article in English | MEDLINE | ID: mdl-34064772

ABSTRACT

Ergot alkaloids are mycotoxins formed by fungi of the Claviceps genus, which are some of the most common contaminants of food and feed worldwide. These toxins are a structurally heterogeneous group of compounds, sharing an ergoline backbone. Six structures and their corresponding stereoisomers are typically quantified by either HPLC-FLD or HPLC-MS/MS and the values subsequently summed up to determine the total ergot alkaloid content. For the development of a screening method targeting all ergot alkaloids simultaneously, the alkaloids need to be transferred to one homogeneous structure: a lysergic acid derivative. In this study, two promising cleaving methods-acidic esterification and hydrazinolysis-are compared, using dihydroergocristine as a model compound. While the acidic esterification proved to be unsuitable, due to long reaction times and oxidation sensitivity, hydrazinolysis reached a quantitative yield in 40‒60 min. Parallel workup of several samples is possible. An increasing effect on the reaction rate by the addition of ammonium iodide was demonstrated. Application of hydrazinolysis to a major ergot alkaloid mix solution showed that all ergopeptines were cleaved, but ergometrine/-inine was barely affected. Still, hydrazinolysis is a suitable tool for the development of a sum parameter screening method for ergot alkaloids in food and feed.


Subject(s)
Claviceps/metabolism , Ergot Alkaloids/analysis , Mycotoxins/analysis , Chromatography, High Pressure Liquid , Ergot Alkaloids/chemistry , Hydrazines/chemistry , Mycotoxins/chemistry , Stereoisomerism , Tandem Mass Spectrometry
8.
Mar Pollut Bull ; 166: 112246, 2021 May.
Article in English | MEDLINE | ID: mdl-33774479

ABSTRACT

Monitoring plastic in stomachs of beached northern fulmars for OSPAR's Ecological Quality Objectives (EcoQOs) has been incorporated into the European Marine Strategy Framework Directive (MSFD). This paper aims to provide the appropriate tools to interpret the monitoring results. MSFD requires a data-derived threshold value (Fulmar-TV) representing 'Good Environmental Status'. Such Fulmar-TV was calculated from near-pristine Canadian Arctic data where 10.06% of fulmars exceeded the level of 0.1 g ingested plastic. This Fulmar-TV is almost identical to the earlier OSPAR EcoQO, arbitrarily set at 10%. The MSFD approach was evaluated for 2661 North Sea fulmars in 2002-2018. Between 2014 and 2018, 51% of 393 fulmars exceeded 0.1 g plastic, significantly above the proposed Fulmar-TV. Linear regression of individual ingested plastic mass over the 2009-2018 period indicates a significant decrease. Over the longer term 2002-2018, logistic regression of annual EcoQ% shows a significant decline and predicts compliance with the Fulmar-TV by 2054.


Subject(s)
Environmental Monitoring , Plastics , Animals , Canada , Eating , Gastrointestinal Contents , North Sea
9.
J Cutan Pathol ; 48(3): 384-389, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33051901

ABSTRACT

Spiradenocarcinoma (SC) is a very rare malignant skin adnexal tumor with sweat gland differentiation that develops from a pre-existing spiradenoma, cylindroma, or hybrid tumor called spiradenocylindroma, or arises de novo. We present two exceptionally rare SC cases showing sarcomatous differentiation; we also discuss the clinicopathologic features of SC, as well as its differential diagnoses and available therapeutic modalities. Given the aggressive behavior of SC, rapid diagnosis and complete removal of the tumor with tumor-free margins is mandatory. Owing to the marked morphological heterogeneity of individual SC cases, dermatopathologists must be familiar with the different possible histopathologic manifestations of this neoplasm.


Subject(s)
Adenocarcinoma/diagnosis , Metaplasia/pathology , Sarcoma/pathology , Skin Neoplasms/pathology , Sweat Gland Neoplasms/pathology , Acrospiroma/complications , Acrospiroma/pathology , Adenocarcinoma/pathology , Adenocarcinoma/surgery , Adult , Aged , Carcinoma, Adenoid Cystic/complications , Carcinoma, Adenoid Cystic/pathology , Cell Differentiation , Diagnosis, Differential , Female , Humans , Immunohistochemistry/methods , Lost to Follow-Up , Margins of Excision , Sarcoma/diagnosis , Skin Neoplasms/surgery , Staining and Labeling/methods , Sweat Gland Neoplasms/surgery
10.
Environ Sci Pollut Res Int ; 28(2): 1643-1655, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32851520

ABSTRACT

Although ingestion of plastic by tubenosed seabirds has been documented regularly, identification of the polymer composition of these plastics has rarely been described. Polymer assessment may assist in identifying sources and may indicate risks from additives occurring in specific types of polymers. Using known test materials, two identification methods Fourier transform infrared spectroscopy and near infrared spectroscopy (FTIR and NIR) were compared. Although both methods were found to be similarly suitable for identification of plastic polymers, a significant difference was observed in identification of natural materials. FTIR frequently misclassified natural materials as being a synthetic polymer. Within our results, an 80% match score threshold functioned best to distinguish between natural items and synthetics. Using NIR, the historical variability of plastics ingested by northern fulmars (Fulmarus glacialis) from the Dutch sector of the North Sea was analysed for three time periods since the 1980s. For the more recent decade, variability between fulmars from different regions in the northeast Atlantic was investigated. Regional variation was further explored by analysing plastics obtained from the stomachs of southern hemisphere relatives of the fulmar (southern fulmar, cape petrel, snow petrel) and Wilson's storm petrel. Results show that proportional abundance of polymer types in these seabirds is closely related to the plastic categories that they ingest (e.g. pellets, foam, fragments). The uptake of different plastic categories and related polymer types most likely reflects spatial and temporal variations in availability rather than ingestion preferences of the birds.


Subject(s)
Environmental Monitoring , Gastrointestinal Contents , Animals , Birds , North Sea , Plastics , Polymers
11.
Mar Pollut Bull ; 151: 110858, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32056640

ABSTRACT

This review quantifies plastic interaction in marine biota. Firstly, entanglement and ingestion records for all marine birds, mammals, turtles, fish, and invertebrate species, are summarized from 747 studies. Marine debris affected 914 species through entanglement and/or ingestion. Ingestion was recorded for 701 species, entanglement was documented for 354 species. Secondly, the frequency of occurrence of ingestion per species (Sp-%FO) was extracted for marine birds, mammals and turtles. Thirdly, for seabird species, average numbers of plastics ingested per individual were determined. Highest Sp-%FO and average number of plastics were found in tubenosed seabirds with 41% of all birds analysed having plastics, on average 9.9 particles per bird. The Sp-%FO and average number of ingested particles is lower for most other species. However, for certain species, ingestion rates of litter are reason for serious concern. Standardized methods are crucial for future studies, to generate datasets that allow higher level ecosystem analyses.


Subject(s)
Environmental Monitoring , Waste Products , Water Pollutants, Chemical , Animals , Dietary Exposure/statistics & numerical data , Eating , Ecosystem , Gastrointestinal Contents , Plastics
12.
J Sep Sci ; 43(6): 1089-1099, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31855312

ABSTRACT

An analytical method was developed for the quantitation of the mineral oil aromatic hydrocarbons in cosmetic raw materials separating those of one or two aromatic rings from those of three and more aromatic rings. Normal phase high performance liquid chromatography was used with donor-acceptor complex chromatography. The composition of both fractions and the quantities of respective compounds were determined by comprehensive two dimensional gas chromatography with time of flight mass spectrometry and by liquid chromatography coupled to gas chromatography with flame ionization detection.

13.
Environ Pollut ; 257: 113569, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31753635

ABSTRACT

This study combines published datasets with unpublished data on plastic ingestion in several North Sea fish species. The combined dataset of 4389 individuals from 15 species allows the analysis of spatial distribution and temporal variability of plastic uptake in fish. Airborne fibre contamination was observed to be the main contributor to fibres encountered in the samples. The number of fibres in samples was strongly related to the time needed to process a sample, not to the number of individual fishes in the sample. Accurate correction for secondary fibre contamination was not possible, but corrections required would be similar to fibre numbers observed in the samples. Consequently, all fibres were omitted from further analysis. The frequency of occurrence and the average number of plastics in fish is generally low (1.8% and 0.022 pieces per organism respectively), with only cod having a higher prevalence (12.3%). While latitude of catch locations influences plastic uptake in fish, no correlation with the distance to the coast was found. Slightly less plastics were ingested in winter, and a decrease in plastics ingested was observed between 2009 and 2018. These factors should be considered when fish species, catch location and time are discussed as indicators for plastic pollution in the European Marine Strategy Framework Directive. We recommend considering demersal cod and pelagic sprat as two species suitable for monitoring plastic ingestion in biota, both on the seafloor and in the water column.


Subject(s)
Fishes , Plastics/adverse effects , Water Pollutants, Chemical , Animals , Eating , Environmental Monitoring , North Sea , Oceans and Seas
14.
Chemosphere ; 213: 103-113, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30216811

ABSTRACT

Studies investigating the effects of plastic litter on marine biota have almost exclusively utilised pristine plastic materials that are homogeneous in polymer type, size, shape and chemical composition. This is particularly the case for microplastics (<5 mm), where collecting sufficient quantities from the marine environment for use in laboratory impacts studies is simply not feasible. Weathered plastics collected from the marine environment show considerable physical and chemical differences to pristine and post-production consumer plastics. For this study, macroplastic litter was collected on a Dutch beach and cryo-milled to create a microplastic mixture for environmental impact assessments. The sample composition followed proportions of marine plastic litter types observed in an earlier large beach clean-up. Polymer composition of the sample was assessed by infrared spectroscopy (ATR-FTIR) and differential scanning calorimetry analysis (DSC). The particle size distribution of the cryo-milled microplastics showed that particles 0.5-2.0 mm represented 68% of mass, but smaller sizes (<2 mm) strongly dominated numerically. Inductively coupled plasma spectroscopy (ICP-MS and ICP-OES) analysis of the microplastic mixture revealed a broad range of metals and other elements (e.g. Al, Cd, Cr, Fe, Mg, Pb, S and Zn), representing common inorganic additives used as colorants, fillers and stabilisers. GC-MS analysis identified a broad range of organic plasticisers, stabilisers, antioxidants and flame retardants. Comparison of different analytical approaches showed that creation of a homogeneous microplastic mixture is possible, representing a first step in closing the gap between laboratory studies with pristine materials and realistic scenarios with weathered microplastic.


Subject(s)
Ecosystem , Environmental Monitoring/methods , Plastics/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/analysis
15.
J Cancer Res Clin Oncol ; 144(5): 809-819, 2018 May.
Article in English | MEDLINE | ID: mdl-29427211

ABSTRACT

PURPOSE: Glioblastoma multiforme (GBM) is the most lethal primary brain tumor in adults. The epigenetically active ribonucleoside analog 5-azacitidine is a new therapy option that changes tumor cell chromatin, which is frequently modified by methylation and deacetylation in malignant gliomas. METHODS: In vitro, we analyzed cell viability, cell apoptosis, and migration of human GBM cells. In vivo, we established subcutaneous and intracerebral GBM mouse models originating from U87MG, U373MG, and primary GBM cells as well as one patient-derived xenograft. Xenografts were treated with 5-azacitidine as well as valproic acid, bevacizumab, temozolomide, and phosphate buffered saline. The tumor sizes and Ki67 proliferation indices were determined. Glioma angiogenesis was examined immunohistochemically by expression analysis of endothelial cells (CD31) and pericytes (PDGFRß). RESULTS: In vitro, 5-azacitidine treatment significantly reduced human glioblastoma cell viability, increased cellular apoptosis, and reduced cellular migration. In vivo, 5-azacitidine significantly reduced growth in two intracerebral GBM models. Notably, this was also shown for a xenograft established from a patient surgery sample; whereas, epigenetically acting valproic acid did not show any growth reduction. Highly vascularized tumors responded to treatment, whereas low-vascularized xenografts showed no response. Furthermore, intracerebral glioblastomas treated with 5-azacitidine showed a clearly visible reduction of tumor angiogenesis and lower numbers of endothelial cells and tumor vessel pericytes. CONCLUSIONS: Our data show significant growth inhibition as well as antiangiogenic effects in intracerebral as well as patient-derived GBM xenografts. This encourages to investigate in detail the multifactorial effects of 5-azacitidine on glioblastomas.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Brain Neoplasms/drug therapy , Glioblastoma/drug therapy , Xenograft Model Antitumor Assays , Animals , Apoptosis/drug effects , Azacitidine/administration & dosage , Azacitidine/pharmacology , Brain Neoplasms/pathology , Cell Line, Tumor , Cell Movement/drug effects , Cell Survival/drug effects , Female , Glioblastoma/pathology , Humans , Mice, Inbred NOD , Mice, Knockout , Mice, Nude , Mice, SCID , Tumor Burden/drug effects
16.
Ambio ; 47(4): 387-397, 2018 May.
Article in English | MEDLINE | ID: mdl-29305788

ABSTRACT

Stomach contents of harbour porpoises (Phocoena phocoena) collected in the Netherlands between 2003 and 2013 were inspected for the presence of plastic and other man-made litter. In 654 stomach samples the frequency of occurrence of plastic litter was 7% with less than 0.5% additional presence of non-synthetic man-made litter. However, we show that when a dedicated standard protocol for the detection of litter is followed, a considerably higher percentage (15% of 81 harbour porpoise stomachs from the period 2010-2013) contained plastic litter. Results thus strongly depended on methods used and time period considered. Occurrence of litter in the stomach was correlated to the presence of other non-food remains like stones, shells, bog-wood, etc., suggesting that litter was often ingested accidentally when the animals foraged close to the bottom. Most items were small and were not considered to have had a major health impact. No evident differences in ingestion were found between sexes or age groups, with the exception that neonates contained no litter. Polyethylene and polypropylene were the most common plastic types encountered. Compared to earlier literature on the harbour porpoise and related species, our results suggest higher levels of ingestion of litter. This is largely due to the lack of dedicated protocols to investigate marine litter ingestion in previous studies. Still, the low frequency of ingestion, and minor number and mass of litter items found in harbour porpoises in the relatively polluted southern North Sea indicates that the species is not a strong candidate for annual monitoring of marine litter trends under the EU marine strategy framework directive. However, for longer-term comparisons and regional differences, with proper dedicated protocols applied, the harbour porpoise has specific use in quantifying litter presence in the, for that specific objective, poorly studied benthic marine habitat.


Subject(s)
Diet , Phocoena , Plastics , Animals , Ecosystem , Netherlands , North Sea , Reference Standards
17.
Turk Neurosurg ; 2018 Oct 17.
Article in English | MEDLINE | ID: mdl-30649824

ABSTRACT

AIM: In glioblastoma multiforme, the balance between the procoagulant system, anticoagulant system and fibrinolytic system is impaired in favour of hypercoagulability. The aim of this study was to compare glioblastoma multiforme with astrocytoma grade II by subjectively evaluating the levels of prothrombin and biotinylation thrombin, and G protein serum protease activatin receptors, as tissue factors causing hypercoagulation and affecting coagulation. MATERIAL AND METHODS: Specimens from 35 cases with glioblastoma multiforme and 23 cases with astrocytoma grade II were evaluated immunohistochemically. The specimens were stained with hematoxylen-eosin and immunohistochemically for prothrombin, biotinylation thrombin and protease activating factor receptors to determine the correlation between the tumor malignancy and coagulation factor receptors. RESULTS: An increase in malignancy was seen to result in an increase in prothrombin, biotinylation thrombin, protein activator receptor 1, protein activator receptor 3, and protein activator receptor 4 levels, and a decrease in protein activator receptor 2 level. These data showedthat there was hypercoagulability in glioblastoma multiforme. Descriptive statistics and Mann-Whitney U analysis were used to evaluate the results. CONCLUSION: In glioblastoma multiforme, if there is no radiologicalevidence of hemorrhage, low molecular weight heparin should be administered peroperatively and continued for 3 months postoperatively to prevent the development of deep venous thrombosis. This will also be useful in the prevention of invasion, angiogenesis, metastasis and tumour progression.

18.
Polar Biol ; 41(6): 1269-1278, 2018.
Article in English | MEDLINE | ID: mdl-31007367

ABSTRACT

One of the recently recognised stressors in Arctic ecosystems concerns plastic litter. In this study, juvenile polar cod (Boreogadus saida) were investigated for the presence of plastics in their stomachs. Polar cod is considered a key species in the Arctic ecosystem. The fish were collected both directly from underneath the sea ice in the Eurasian Basin and in open waters around Svalbard. We analysed the stomachs of 72 individuals under a stereo microscope. Two stomachs contained non-fibrous microplastic particles. According to µFTIR analysis, the particles consisted of epoxy resin and a mix of Kaolin with polymethylmethacrylate (PMMA). Fibrous objects were excluded from this analysis to avoid bias due to contamination with airborne micro-fibres. A systematic investigation of the risk for secondary micro-fibre contamination during analytical procedures showed that precautionary measures in all procedural steps are critical. Based on the two non-fibrous objects found in polar cod stomachs, our results show that ingestion of microplastic particles by this ecologically important fish species is possible. With increasing human activity, plastic ingestion may act as an increasing stressor on polar cod in combination with ocean warming and sea-ice decline in peripheral regions of the Arctic Ocean. To fully assess the significance of this stressor and its spatial and temporal variability, future studies must apply a rigorous approach to avoid secondary pollution.

19.
Mar Pollut Bull ; 115(1-2): 86-90, 2017 Feb 15.
Article in English | MEDLINE | ID: mdl-27912918

ABSTRACT

In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.


Subject(s)
Aquatic Organisms/metabolism , Hydroxides/chemistry , Plastics/isolation & purification , Potassium Compounds/chemistry , Water Pollutants, Chemical/isolation & purification , Eating , Environmental Monitoring , Waste Products
20.
Praxis (Bern 1994) ; 103(23): 1385-96, 2014 Nov 12.
Article in German | MEDLINE | ID: mdl-25391745

ABSTRACT

Low-grade gliomas (LGG) are brain tumors with a low or intermediate biological aggressiveness. According to histopathological features, they are further specified as grade I or II by WHO criteria. Diffuse astrocytomas, oligodendrogliomas, and mixed gliomas are the most common LGG. They mainly affect young patients in their 3rd to 5th decade and often manifest with epileptic seizures. A macroscopically complete or near-complete tumor resection that does not induce additional neurological deficits, is recommended as first line therapy in surgically accessible tumors, as a significant benefit for overall survival has been demonstrated. The indication for adjuvant chemo- or radiotherapy must be discussed interdisciplinary in each case. MGMT promotor methylation, LOH 1p/19q, as well as the status of somatic mutations within IDH1/2 gene constitute biomarkers that may predict response to adjuvant therapy and may correlate to overall survival. These and other biomarkers could be of benefit in future managing plans to offer patients with LGG an individually tailored, optimal treatment.


Les gliomes de bas grade (GBG) sont des lésions tumorales cérébrales primaires considérées à potentiel malin faible à modéré; l'Organisation Mondiale de la Santé les a classés de grades I et II. Les astrocytomes, les oligodendrogliomes et les gliomes mixtes constituent des sous-groupes. Les GBG sont principalement retrouvés chez les jeunes patients et se manifestent souvent par des crises épileptiques. La résection tumorale complète, dans la mesure où elle ne cause pas de dysfonction neurologique, est considérée comme le traitement de première ligne, car elle améliore significativement la survie globale. L'indication à une radiothérapie et/ou une chimiothérapie adjuvantes doit être discutée au cas par cas à la consultation multidisciplinaire. La connaissance de biomarqueurs tels que le MGMT (et de son éventuelle méthylation), et le status, muté ou non, de 1p/19q et IDH1/2- peuvent être utiles en raison de la répercussion sur le traitement et la survie globale. À l'avenir, ces marqueurs (et d'autres encore) pourraient être utilisés pour fournir un traitement personnalisé, par conséquent avec un résultat thérapeutique optimal pour les patients atteints de GBG.


Subject(s)
Brain Neoplasms/pathology , Glioma/pathology , Adult , Biopsy , Brain/pathology , Brain Neoplasms/therapy , Chemotherapy, Adjuvant , Combined Modality Therapy , Female , Glioma/diagnosis , Glioma/therapy , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Postoperative Complications/diagnosis , Prognosis , Radiotherapy, Adjuvant , Tomography, X-Ray Computed
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