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1.
Environ Sci Technol ; 57(48): 20159-20168, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37934924

RESUMEN

Research on per- and polyfluoroalkyl substances (PFAS) frequently incorporates organofluorine measurements, particularly because they could support a class-based approach to regulation. However, standardized methods for organofluorine analysis in a broad suite of matrices are currently unavailable, including a method for extractable organofluorine (EOF) measured using combustion ion chromatography (CIC). Here, we report the results of an international interlaboratory comparison. Seven laboratories representing academia, government, and the private sector measured paired EOF and PFAS concentrations in groundwater and eel (Anguilla rostrata) from a site contaminated by aqueous film-forming foam. Among all laboratories, targeted PFAS could not explain all EOF in groundwater but accounted for most EOF in eel. EOF results from all laboratories for at least one replicate extract fell within one standard deviation of the interlaboratory mean for groundwater and five out of seven laboratories for eel. PFAS spike mixture recoveries for EOF measurements in groundwater and eel were close to the criterion (±30%) for standardized targeted PFAS methods. Instrumental operation of the CIC such as replicate sample injections was a major source of measurement uncertainty. Blank contamination and incomplete inorganic fluorine removal may introduce additional uncertainties. To elucidate the presence of unknown organofluorine using paired EOF and PFAS measurements, we recommend that analysts carefully consider confounding methodological uncertainties such as differences in precision between measurements, data processing steps such as blank subtraction and replicate analyses, and the relative recoveries of PFAS and other fluorine compounds.


Asunto(s)
Anguilla , Fluorocarburos , Agua Subterránea , Contaminantes Químicos del Agua , Animales , Fluorocarburos/análisis , Agua Subterránea/química , Agua , Flúor/análisis , Flúor/química , Contaminantes Químicos del Agua/análisis
2.
Chemistry ; 27(3): 928-933, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-32579239

RESUMEN

Arabinogalactan, a microheterogeneous polysaccharide occurring in plants, is known for its allergy-protective activity, which could potentially be used for preventive allergy treatment. New treatment options are highly desirable, especially in a preventive manner, due to the constant rise of atopic diseases worldwide. The structural origin of the allergy-protective activity of arabinogalactan is, however, still unclear and isolation of the polysaccharide is not feasible for pharmaceutical applications due to a variation of the activity of the natural product and contaminations with endotoxins. Therefore, a pentasaccharide partial structure was selected for total synthesis and subsequently coupled to a carrier protein to form a neoglycoconjugate. The allergy-protective activity of arabinogalactan could be reproduced with the partial structure in subsequent in vivo experiments. This is the first example of a successful simplification of arabinogalactan with a single partial structure while retaining its allergy-preventive potential.

3.
Anal Bioanal Chem ; 413(1): 103-115, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33164152

RESUMEN

In this study, we compare combustion ion chromatography (CIC) and high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) with respect to their applicability for determining organically bound fluorine sum parameters. Extractable (EOF) and adsorbable (AOF) organically bound fluorine as well as total fluorine (TF) were measured in samples from river Spree in Berlin, Germany, to reveal the advantages and disadvantages of the two techniques used as well as the two established fluorine sum parameters AOF and EOF. TF concentrations determined via HR-CS-GFMAS and CIC were comparable between 148 and 270 µg/L. On average, AOF concentrations were higher than EOF concentrations, with AOF making up 0.14-0.81% of TF (determined using CIC) and EOF 0.04-0.28% of TF (determined using HR-CS-GFMAS). The results obtained by the two independent methods were in good agreement. It turned out that HR-CS-GFMAS is a more sensitive and precise method for fluorine analysis compared to CIC. EOF and AOF are comparable tools in risk evaluation for the emerging pollutants per- and polyfluorinated alkyl substances; however, EOF is much faster to conduct. Graphical abstract.

5.
Pediatr Diabetes ; 15(6): 428-35, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24350794

RESUMEN

AIMS/HYPOTHESIS: Aim of this study was to test Wilkin's 'accelerator hypothesis': whether excessive weight gain accelerates the onset of type 1 diabetes. SUBJECTS AND METHODS: Anthropometric birth data of 1117 children who developed diabetes between 1988 and April 2013 were compared with those of a sex, age, and gestational age matched, contemporary regional control group (n = 54 344). Cases were divided into three manifestation groups (G1:0-4.9 yr, G2:5-9.9 yr, and G3: 10-20 yr). Furthermore, growth data of 540 children with diabetes were compared with controls (n = 134 249) in pre-, peri-, and post-onset intervals (interval: 1-6). Also, correlation of age at onset and body mass index (BMI) standard deviation score (SDS) at this point of time were examined. RESULTS: Cases had significantly higher SDSs for birth weight when compared with controls (boys: p = 0.007, girls: p = 0.002). Children with early manifestation had the highest mean of birth weight SDS (G1>G2>G3), (p = 0.22, adjusted r(2) = 0.001). BMI SDS trend curves of cases are slightly higher compared with those of the healthy controls. This was only significant in years after diagnosis (interval 6, p < 0.000). Cases did not show excessive weight gain in any of the examined intervals before the onset of diagnosis (interval 1-3). One year after diagnosis, we found an inverse correlation between age at diagnosis and BMI SDS at diabetes manifestation. The youngest children at diagnosis (G1) had the lowest BMI SDS at manifestation and vice versa (G1

Asunto(s)
Peso al Nacer/fisiología , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/etiología , Macrosomía Fetal/complicaciones , Aumento de Peso/fisiología , Adolescente , Adulto , Edad de Inicio , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Macrosomía Fetal/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Modelos Teóricos , Adulto Joven
6.
Analyst ; 139(17): 4200-9, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-24995477

RESUMEN

SR-FTIR in combination with Principal Component Analysis (PCA) was applied to investigate macromolecular changes in a population of melanocytes and their extracted nuclei induced by environmentally relevant fluxes of UVR (Ultraviolet Radiation). Living cells and isolated cellular nuclei were investigated post-irradiation for three different irradiation dosages (130, 1505, 15,052 Jm(-2) UVR, weighted) after either 24 or 48 hours of incubation. DNA conformational changes were observed in cells exposed to an artificial UVR solar-simulator source as evidenced by a shift in the DNA asymmetric phosphodiester vibration from 1236 cm(-1) to 1242 cm(-1) in the case of the exposed cells and from 1225 cm(-1) to 1242 cm(-1) for irradiated nuclei. PCA Scores plots revealed distinct clustering of spectra from irradiated cells and nuclei from non-irradiated controls in response to the range of applied UVR radiation doses. 3D Raman confocal imaging in combination with k-means cluster analysis was applied to study the effect of the UVR radiation exposure on cellular nuclei. Chemical changes associated with apoptosis were detected and included intra-nuclear lipid deposition along with chromatin condensation. The results reported here demonstrate the utility of SR-FTIR and Raman spectroscopy to probe in situ DNA damage in cell nuclei resulting from UVR exposure. These results are in agreement with the increasing body of evidence that lipid accumulation is a characteristic of aggressive cancer cells, and are involved in the production of membranes for rapid cell proliferation.


Asunto(s)
Núcleo Celular/efectos de la radiación , Conformación de Ácido Nucleico/efectos de la radiación , Piel/citología , Piel/efectos de la radiación , Línea Celular Tumoral , Núcleo Celular/química , ADN/química , Humanos , Análisis de la Célula Individual , Piel/química , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Rayos Ultravioleta
7.
Waste Manag ; 189: 421-426, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39241560

RESUMEN

The analysis of the presence and content of substances that are toxic to aquatic life in waste is essential for classification of waste with regard to hazard property (HP) 14 'ecotoxic'. For the determination of HP14 classified copper (Cu) and zinc (Zn) compounds in various municipal solid waste incineration bottom ashes (IBA) and one fly ash (FA) from Germany we applied X-ray absorption near-edge structure (XANES) spectroscopy in combination with linear combination fitting. The analysis showed that approx. 50-70% of Cu in the IBA are Cu(I) compounds and elemental Cu(0), but these compounds were not equally distributed in the different IBA. In contrast, the majority (approx. 50-70%) of Zn in all IBA is elemental zinc, which originates from brass or other alloys and galvanized metals with a large content of zinc in the waste. The FA contain higher mass fraction on Zn and other toxic elements, but similar Cu and Zn species. Additional performed selective extraction at a pH of 4 with an organic acid of some IBA showed that the ecotoxic Zn fraction is mainly elemental zinc and zinc oxide. In contrast, for the ecotoxic Cu fraction within the IBA no specific compound could be identified. Furthermore, the XANES analysis showed that the HP14 properties of especially Cu in IBA is overestimated with current best-practice guidelines for sample processing for the current substance-related approach with the 0.1% cut-off rule for each substance. However, it should be considered whether it would not be better from an environmental point of view to take the ecotoxicologically leachable copper and zinc as a reference value.


Asunto(s)
Ceniza del Carbón , Cobre , Incineración , Residuos Sólidos , Zinc , Ceniza del Carbón/química , Ceniza del Carbón/análisis , Cobre/análisis , Zinc/análisis , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Alemania , Espectroscopía de Absorción de Rayos X
8.
Eur Urol Focus ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39244510

RESUMEN

Bacteria develop biofilms for protection and persistent colonization. Biofilms of pathogenic bacteria can lead to serious medical problems. Bacterial biofilms on catheters used in the treatment of urinary tract diseases represent a major challenge for antibiotic therapy. Several attempts to eradicate biofilms using classical antibiotics and various alternatives, including antibiotic treatment of surfaces, surfaces that release silver ions, and surfaces with anti-adhesive properties, have not shown clinical efficacy in biofilm prevention or removal. Pseudomonas aeruginosa is one of the most problematic biofilm-forming uropathogens and accounts for approximately 10% of urinary tract infections. Novel glycomimetics that inhibit bacterial lectins have shown promising results in the prevention of P. aeruginosa biofilms and in interference with bacterial virulence. This mini-review summarizes the status of glycomimetic development and provides a perspective on their use in clinical practice. PATIENT SUMMARY: For patients with recurrent urinary tract infections and patients needing long-term catheter use to manage urinary problems, biofilms formed by bacteria can be a problem and are difficult to treat. New compounds that mimic carbohydrates, called glycomimetics, have shown promise in inhibiting these bacteria and the biofilms they form. More research on these compounds is needed before they can be used to treat patients.

9.
Chemosphere ; 351: 141200, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228192

RESUMEN

Here, we report a comparative study of different sum parameter analysis methods for the extraction of per- and polyfluoroalkyl substances (PFAS) from manufactured consumer products, which can be measured by combustion ion chromatography (CIC). Therefore, a hydrolysis-based extraction method was further developed, which accounts for the addition of hydrolyzable covalently bound polyfluoroalkylated side-chain polymers (SFPs) to the extractable organic fluorine portion of the mass balance proposed as "hydrolyzable organically bound fluorine" (HOF). To test this hypothesis, the method was applied to 39 different consumer products containing fluoropolymers or monomeric PFAS taken from four different categories: outdoor textiles, paper packaging, carpeting, and permanent baking sheets. We also evaluated the method's efficiency by extracting four synthesized fluorotelomer polyacrylate reference compounds. The total fluorine (TF) and extractable organically bound fluorine (EOF) values were measured through CIC using established protocols. The TF values ranged from sub-ppb to %-levels, depending on the compound class. All samples showed results for hydrolyzed organofluorine (HOF) between 0.03 and 76.3 µg/g, while most EOF values were lower (

Asunto(s)
Polímeros de Fluorocarbono , Fluorocarburos , Polímeros de Fluorocarbono/análisis , Fluorocarburos/análisis , Cromatografía Liquida , Flúor/química , Espectrometría de Masas en Tándem , Concentración de Iones de Hidrógeno
10.
Chembiochem ; 14(12): 1485-93, 2013 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-23873779

RESUMEN

The interaction between the O-chain from the lipopolysaccharide from Burkholderia anthina and a lipopolysaccharide-specific monoclonal antibody (5D8) has been studied at high resolution by NMR spectroscopy. In particular, the 5D8-bound epitope of the saccharide entity has been unraveled by a combination of saturation transfer difference (STD) and transferred NOESY (tr-NOESY) experiments performed on the 5D8/polysaccharide complex. To dissect the fine details of the molecular recognition events, further experiments with simpler carbohydrate ligands were carried out. Thus, experiments were also performed with ad hoc synthesized trisaccharide and hexasaccharide O-antigen repeating units. By using this multidisciplinary approach (chemical synthesis, NMR spectroscopy and molecular dynamics simulation), determination of the binding epitope and the contribution to the binding of the sugar units composing the O-chain have been determined.


Asunto(s)
Anticuerpos Monoclonales/química , Burkholderia/química , Lipopolisacáridos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Antígenos O/química , Secuencia de Carbohidratos , Disacáridos/química , Simulación de Dinámica Molecular , Trisacáridos/química
11.
Environ Sci Technol ; 47(1): 563-7, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23189972

RESUMEN

Sewage sludge ash (SSA) is a prospective phosphorus source for the future production of recycling P-fertilizers. Due to its high heavy metals contents and the relatively low P plant-availability, SSA must be treated before agricultural utilisation. In this paper SSA was thermochemically treated with PVC in a bench-scale rotary furnace in order to remove heavy metals via the chloride pathway. PVC has a high Cl-content of 52-53% and a high heating value that can be beneficially used for the thermochemical process. Large amounts of waste PVC are already recovered in recycling processes, but there are still some fractions that would be available for the proposed thermochemical process, for example, the low quality near-infrared(NIR)-fraction from waste separation facilities. Heavy metals were effectively removed at temperatures in the range of 800-950 °C via the gas phase by utilisation of PVC as Cl-donor. The resulting P plant-availability was comparable to SSA thermochemically treated with MgCl(2) as Cl-donor if MgO was used as an additive (Mg-donor). A further increase of the plant availability of phosphorus was achieved by acid post-treatment of the thermochemically treated SSA.


Asunto(s)
Residuos Industriales , Metales Pesados/química , Fósforo/química , Cloruro de Polivinilo/química , Aguas del Alcantarillado , Ácido Cítrico/química , Fertilizantes , Calor , Incineración , Compuestos de Amonio Cuaternario/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
12.
Environ Sci Process Impacts ; 25(7): 1213-1223, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37335293

RESUMEN

For the first time, µ-X-ray fluorescence (µ-XRF) mapping combined with fluorine K-edge µ-X-ray absorption near-edge structure (µ-XANES) spectroscopy was applied to depict per- and polyfluoroalkyl substance (PFAS) contamination and inorganic fluoride in sample concentrations down to 100 µg kg-1 fluoride. To demonstrate the matrix tolerance of the method, several PFAS contaminated soil and sludge samples as well as selected consumer product samples (textiles, food contact paper and permanent baking sheets) were investigated. µ-XRF mapping allows for a unique element-specific visualization at the sample surface and enables localization of fluorine containing compounds to a depth of 1 µm. Manually selected fluorine rich spots were subsequently analyzed via fluorine K-edge µ-XANES spectroscopy. To support spectral interpretation with respect to inorganic and organic chemical distribution and compound class determination, linear combination (LC) fitting was applied to all recorded µ-XANES spectra. Complementarily, solvent extracts of all samples were target-analyzed via LC-MS/MS spectrometry. The detected PFAS sum values range from 20 to 1136 µg kg-1 dry weight (dw). All environmentally exposed samples revealed a higher concentration of PFAS with a chain length > C8 (e.g. 580 µg kg-1 dw PFOS for Soil1), whereas the consumer product samples showed a more uniform distribution with regard to chain lengths from C4 to C8. Independent of quantified PFAS amounts via target analysis, µ-XRF mapping combined with µ-XANES spectroscopy was successfully applied to detect both point-specific concentration maxima and evenly distributed surface coatings of fluorinated organic contaminants in the corresponding samples.


Asunto(s)
Flúor , Fluorocarburos , Espectroscopía de Absorción de Rayos X , Rayos X , Fluoruros , Cromatografía Liquida , Espectrometría de Masas en Tándem
13.
Pathogens ; 11(10)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36297233

RESUMEN

Urinary tract infections (UTIs) affect a major proportion of the world population but have limited non-antibiotic-based therapeutic and preventative strategies against UTIs. Facultative intracellular uropathogens such as strains of uropathogenic E. coli, K. pneumoniae, E. faecalis, E. cloacae are well-known uropathogens causing UTIs. These pathogens manipulate several host-signaling pathways during infection, which contributes to recurrent UTIs and inappropriate antibiotic application. Since host cell receptor tyrosine kinases (RTKs) are critical for the entry, survival and replication of intracellular pathogens, we investigated whether different uropathogens require host EPHA2 receptors for their intracellular survival using a cell culture model of intracellular infection in human bladder epithelial cells (BECs). Infection of BECs with seven different uropathogens enhanced the expression levels and activation of EPHA2. The significance of EPHA2 signaling for uropathogen infection was investigated by silencing EPHA2 expression using RNA interference or by inhibiting the kinase activity of EPHA2 using small-molecule compounds such as dasatinib or ALW-II-41-27. Both preventive and therapeutic tyrosine kinase inhibition significantly reduced the intracellular bacterial load. Thus, our results demonstrate the involvement of host cell EPHA2 receptor during intracellular uropathogen infection of BECs, and targeting RTK activity is a viable non-antibiotic therapeutic strategy for managing recurrent UTIs.

14.
Environ Sci Pollut Res Int ; 29(18): 26889-26899, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34860340

RESUMEN

For the first time, fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy was applied to detect per- and polyfluoroalkyl substances (PFAS) in various soil and sewage sludge samples. The method can be used to determine the speciation of inorganic and organic fluorides, without pre-treatment of solid samples. Therefore, XANES spectra of several inorganic fluorides as well as selected fluorinated organic compounds were recorded. While inorganic fluorides partially exhibit a variety of sharp spectral features in the XANES spectrum, almost all inspected organofluorine compounds show two distinct broad features at 688.5 and 692.0 eV. Moreover, the peak intensity ratio 688.5 eV/692.0 eV in the PFAS XANES spectrum can be inversely correlated to the chain length of the perfluoro sulfonic acid group. The detection of targeted PFAS by bulk-XANES spectroscopy in combination with linear combination fitting in soils and sewage sludges was not applicable due to the low organic fluorine to total fluorine ratio of the samples (0.01-1.84%). Nonetheless, direct analysis of pure PFAS revealed that analysis of organofluorine species might be achieved in higher concentrated samples. Furthermore, quantitative measurements by combustion ion chromatography (CIC) evaluated as sum parameters extractable organically bound fluorine (EOF) and total fluorine (TF) emphasize that besides soils, sewage sludges are a significant source of organic fluorine in agriculture (154-7209 µg/kg).


Asunto(s)
Fluorocarburos , Aguas del Alcantarillado , Cromatografía , Fluoruros/análisis , Flúor/análisis , Fluorocarburos/análisis , Suelo/química , Espectroscopía de Absorción de Rayos X
15.
Environ Sci Technol ; 45(17): 7445-50, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21819089

RESUMEN

Sewage sludge ash (SSA) is a suitable raw material for fertilizers due to its high phosphorus (P) content. However, heavy metals must be removed before agricultural application and P should be transferred into a bioavailable form. The utilization of gaseous hydrochloric acid for thermochemical heavy metal removal from SSA at approximately 1000 °C was investigated and compared to the utilization of alkaline earth metal chlorides. The heavy metal removal efficiency increased as expected with higher gas concentration, longer retention time and higher temperature. Equivalent heavy metal removal efficiency were achieved with these different Cl-donors under comparable conditions (150 g Cl/kg SSA, 1000 °C). In contrast, the bioavailability of the P-bearing compounds present in the SSA after thermal treatment with gaseous HCl was not as good as the bioavailability of the P-bearing compounds formed by the utilization of magnesium chloride. This disadvantage was overcome by mixing MgCO(3) as an Mg-donor to the SSA before thermochemical treatment with the gaseous Cl-donor. A test series under systematic variation of the operational parameters showed that copper removal is more depending on the retention time than the removal of zinc. Zn-removal was declined by a decreasing ratio of the partial pressures of ZnCl(2) and water.


Asunto(s)
Gases/química , Ácido Clorhídrico/química , Metales Pesados/química , Aguas del Alcantarillado/química , Calor , Incineración , Fósforo/química , Eliminación de Residuos Líquidos/instrumentación , Eliminación de Residuos Líquidos/métodos
16.
Ber Wiss ; 39(4): 299-310, 2016 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-33008241
17.
Materials (Basel) ; 14(9)2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33925043

RESUMEN

Clinching continuous fibre reinforced thermoplastic composites and metals is challenging due to the low ductility of the composite material. Therefore, a number of novel clinching technologies has been developed specifically for these material combinations. A systematic overview of these advanced clinching methods is given in the present paper. With a focus on process design, three selected clinching methods suitable for different joining tasks are described in detail. The clinching processes including equipment and tools, observed process phenomena and the resultant material structure are compared. Process phenomena during joining are explained in general and compared using computed tomography and micrograph images for each process. In addition the load bearing behaviour and the corresponding failure mechanisms are investigated by means of single-lap shear tests. Finally, the new joining technologies are discussed regarding application relevant criteria.

18.
Materials (Basel) ; 14(14)2021 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-34300806

RESUMEN

Generative hybridization enables the efficient production of lightweight structures by combining classic manufacturing processes with additive manufacturing technologies. This type of functionalization process allows components with high geometric complexity and high mechanical properties to be produced efficiently in small series without the need for additional molds. In this study, hybrid specimens were generated by additively depositing PA6 (polyamide 6) via fused layer modeling (FLM) onto continuous woven fiber GF/PA6 (glass fiber/polyamide 6) flat preforms. Specifically, the effects of surface pre-treatment and process-induced surface interactions were investigated using optical microscopy for contact angle measurements as well as laser profilometry and thermal analytics. The bonding characteristic at the interface was evaluated via quasi-static tensile pull-off tests. Results indicate that both the bond strength and corresponding failure type vary with pre-treatment settings and process parameters during generative hybridization. It is shown that both the base substrate temperature and the FLM nozzle distance have a significant influence on the adhesive tensile strength. In particular, it can be seen that surface activation by plasma can significantly improve the specific adhesion in generative hybridization.

19.
Materials (Basel) ; 14(9)2021 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-34065095

RESUMEN

Continuous carbon fibre-reinforced thermoplastic composites have convincing anisotropic properties, which can be used to strengthen structural components in a local, variable and efficient way. In this study, an additive manufacturing (AM) process is introduced to fabricate in situ consolidated continuous fibre-reinforced polycarbonate. Specimens with three different nozzle temperatures were in situ consolidated and tested in a three-point bending test. Computed tomography (CT) is used for a detailed analysis of the local material structure and resulting material porosity, thus the results can be put into context with process parameters. In addition, a highly curved test structure was fabricated that demonstrates the limits of the process and dependent fibre strand folding behaviours. These experimental investigations present the potential and the challenges of additive manufacturing-based in situ consolidated continuous fibre-reinforced polycarbonate.

20.
Bioorg Med Chem ; 18(17): 6275-81, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20696583

RESUMEN

This paper describes a new method for the preparation of 1,5-bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadien-3-one 1 and its derivatives 2-5. This set of synthetic compounds exhibited high antitumoral activities regarding in vitro screening against several human tumor cell lines as lung carcinoma NCI-460, melanoma UACC-62, breast MCF-7, colon HT-29, renal 786-O, ovarian OVCAR-03 and ovarian expressing the resistance phenotype for adriamycin NCI-ADR/RES, prostate PC-3, and leukemia K-562. Compounds were also tested against murine tumor cell line B16F10 melanoma and lymphocytic leukemia L1210 as well as to their effect toward normal macrophages. Specific activity against colon cancer cells HT-29 was observed for all tested compounds and suggests further studies with models of colon cancer. Compounds 1, 2, and 4 showed significant cytotoxic activity with IC(50) values 2.3 microM for all human cancer cell lines. Intraperitoneal acute administration of compound 1 and 2 showed very low toxicity rate.


Asunto(s)
Anisoles/farmacología , Antineoplásicos/farmacología , Cetonas/farmacología , Animales , Anisoles/síntesis química , Anisoles/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Cetonas/síntesis química , Cetonas/química , Ratones , Relación Estructura-Actividad
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