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1.
Atmos Environ (1994) ; 163: 138-154, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30519142

RESUMO

Inhalation of particulate matter (PM) from residential biomass combustion is epidemiologically associated with cardiovascular and pulmonary diseases. This study investigates PM0.4-1 emissions from combustion of commercial Miscanthus straw (MS), softwood chips (SWC) and beech wood chips (BWC) in a domestic-scale boiler (40 kW). The PM0.4-1 emitted during combustion of the MS, SWC and BWC were characterized by ICP-MS/OES, XRD, SEM, TEM, and DLS. Cytotoxicity and genotoxicity in human alveolar epithelial A549 and human bronchial epithelial BEAS-2B cells were assessed by the WST-1 assay and the DNA-Alkaline Unwinding Assay (DAUA). PM0.4-1 uptake/translocation in cells was investigated with a new method developed using a confocal reflection microscope. SWC and BWC had a inherently higher residual water content than MS. The PM0.4-1 emitted during combustion of SWC and BWC exhibited higher levels of Polycyclic Aromatic Hydrocarbons (PAHs), a greater variety of mineral species and a higher heavy metal content than PM0.4-1 from MS combustion. Exposure to PM0.4-1 from combustion of SWC and BWC induced cytotoxic and genotoxic effects in human alveolar and bronchial cells, whereby the strongest effect was observed for BWC and was comparable to that caused by diesel PM (SRM 2 975), In contrast, PM0.4-1 from MS combustion did not induce cellular responses in the studied lung cells. A high PAH content in PM emissions seems to be a reliable chemical marker of both combustion efficiency and particle toxicity. Residual biomass water content strongly affects particulate emissions and their toxic potential. Therefore, to minimize the harmful effects of fine PM on health, improvement of combustion efficiency (aiming to reduce the presence of incomplete combustion products bound to PM) and application of fly ash capture technology, as well as use of novel biomass fuels like Miscanthus straw is recommended.

2.
Altern Ther Health Med ; 23(2): 28-34, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28323626

RESUMO

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


Assuntos
Fogachos/tratamento farmacológico , Lythraceae/química , Menopausa/efeitos dos fármacos , Extratos Vegetais/farmacologia , Óleos de Plantas/administração & dosagem , Sementes/química , Estudos de Coortes , Estradiol , Feminino , Humanos , Óleos de Plantas/farmacologia , Resultado do Tratamento , Saúde da Mulher
3.
Arch Toxicol ; 90(12): 3111-3123, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26856714

RESUMO

Aim of this study was the investigation of the genotoxic properties of XLR-11 [1-(5-fluoropentyl)-1H-indol-3-yl](2,2,3,3-tetramethylcyclopropyl)methanone, a widely consumed synthetic cannabinoid (SC), and of the benzoyl indole RCS-4 (4-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone). We characterized the DNA-damaging properties of these drugs in different experimental systems. No evidence for induction of gene mutations was detected in bacterial (Salmonella/microsome) tests, but clear dose-dependent effects were found in in vitro single cell gel electrophoresis (SCGE) assays with human lymphocytes and with buccal- and lung-derived human cell lines (TR-146 and A-549). These experiments are based on the determination of DNA migration in an electric field and enable the detection of single- and double-strand breaks and apurinic sites. Furthermore, we found that both drugs induce micronuclei which are formed as a consequence of chromosomal aberrations. The lack of effects in SCGE experiments with lesion-specific enzymes (FPG, Endo III) shows that the DNA damage is not caused by formation of oxidatively damaged bases; experiments with liver enzyme homogenates and bovine serum albumin indicate that the drugs are not converted enzymatically to DNA-reactive intermediates. Furthermore, results with buccal- and lung-derived human cells show that gaseous treatment of the cells under conditions which reflect the exposure situation in drug users may cause damage of the genetic material in epithelia of the respiratory tract. Since DNA instability is involved in the etiology of cancer, these findings can be taken as an indication that consumption of the SCs may cause tumors in the respiratory tract of consumers.


Assuntos
Canabinoides/toxicidade , Dano ao DNA , Drogas Desenhadas/toxicidade , Mutagênicos/toxicidade , Mucosa Respiratória/efeitos dos fármacos , Neoplasias do Sistema Respiratório/induzido quimicamente , Células A549 , Biotransformação , Canabinoides/metabolismo , Linhagem Celular , Células Cultivadas , Ensaio Cometa , Drogas Desenhadas/metabolismo , Humanos , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Testes para Micronúcleos , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Mutagênicos/metabolismo , Mutação/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Absorção pelo Trato Respiratório , Neoplasias do Sistema Respiratório/metabolismo , Neoplasias do Sistema Respiratório/patologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/enzimologia , Salmonella typhimurium/metabolismo
4.
Chem Res Toxicol ; 26(5): 693-702, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23607891

RESUMO

In a recent study, magnetite was investigated for its potential to induce toxic effects and influence signaling pathways. It was clearly demonstrated that ROS formation leads to mitochondrial damage and genotoxic effects in A549 cells. On the basis of these findings, we wanted to elucidate the origin of magnetite-mediated ROS formation and its influence on the cell cycle of A549 and H1299 human lung epithelial cells. Concentration- and size-dependent superoxide formation, measured by electron paramagnetic resonance (EPR), was observed. Furthermore, we could show that the GSH level decreased significantly after exposure to magnetite particles, while catalase (CAT) activity was increased. These effects were also dependent on particle size, albeit less pronounced than those observed with EPR. We were able to show that incubation of A549 cells prior to particle treatment with diphenyleneiodonium (DPI), a NADPH-oxidase (NOX) inhibitor, leads to decreased ROS formation, but this effect was not observed for the NOX inhibitor apocynin. Soluble iron does not contribute considerably to ROS production. Analysis of cell-cycle distribution revealed a pronounced sub-G1 peak, which cannot be linked to increased cell death. Western blot analysis did not show activation of p53 but upregulation of p21 in A549. Here, we were unexpectedly able to demonstrate that exposure to magnetite leads to p21-mediated G1-like arrest. This has been reported previously only for low concentrations of microtubule stabilization drugs. Importantly, the arrested sub-G1 cells were viable and showed no caspase 3/7 activation.


Assuntos
Ciclo Celular/efeitos dos fármacos , Pulmão/patologia , Nanopartículas de Magnetita/química , Estresse Oxidativo/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Oniocompostos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas , Quinases Ativadas por p21/metabolismo
5.
Mutat Res ; 755(2): 163-6, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23817106

RESUMO

Conflicting results have been published regarding the induction of genotoxic effects by exposure to radiofrequency electromagnetic fields (RF-EMF). Various results indicating a genotoxic potential of RF-EMF were reported by the collaborative EU-funded REFLEX (Risk Evaluation of Potential Environmental Hazards From Low Energy Electromagnetic Field Exposure Using Sensitive in vitro Methods) project. There has been a long-lasting scientific debate about the reliability of the reported results and an attempt to reproduce parts of the results obtained with human fibroblasts failed. Another part of the REFLEX study was performed in Berlin with the human lymphoblastoid cell line HL-60; genotoxic effects of RF-EMF were measured by means of the comet assay and the micronucleus test. The plausibility and reliability of these results were also questioned. In order to contribute to a clarification of the biological significance of the reported findings, a repeat study was performed, involving scientists of the original study. Comet-assay experiments and micronucleus tests were performed under the same experimental conditions that had led to genotoxic effects in the REFLEX study. Here we report that the attempts to reproduce the induction of genotoxic effects by RF-EMF in HL-60 cells failed. No genotoxic effects of RF-EMF were measured in the repeat experiments. We could not find an explanation for the conflicting results. However, the negative repeat experiments suggest that the biological significance of genotoxic effects of RF-EMF reported by the REFLEX study should be re-assessed.


Assuntos
Células HL-60/efeitos da radiação , Ondas de Rádio/efeitos adversos , Ensaio Cometa , Humanos , Testes para Micronúcleos , Estudos Multicêntricos como Assunto , Reprodutibilidade dos Testes , Projetos de Pesquisa
6.
Chem Res Toxicol ; 25(12): 2687-703, 2012 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-23116259

RESUMO

Ambient airborne particulate matter is known to cause various adverse health effects in humans. In a recent study on the environmental impacts of coal and tire combustion in a thermal power station, fine crystals of PbSO(4) (anglesite), ZnSO(4)·H(2)O (gunningite), and CaSO(4) (anhydrite) were identified in the stack emissions. Here, we have studied the toxic potential of these sulfate phases as particulates and their uptake in human alveolar epithelial cells (A549). Both PbSO(4) and CaSO(4) yielded no loss of cell viability, as determined by the WST-1 and NR assays. In contrast, a concentration-dependent increase in cytotoxicity was observed for Zn sulfate. For all analyzed sulfates, an increase in the production of reactive oxygen species (ROS), assessed by the DCFH-DA assay and EPR, was observed, although to a varying extent. Again, Zn sulfate was the most active compound. Genotoxicity assays revealed concentration-dependent DNA damage and induction of micronuclei for Zn sulfate and, to a lower extent, for CaSO(4), whereas only slight effects could be found for PbSO(4). Moreover, changes of the cell cycle were observed for Zn sulfate and PbSO(4). It could be shown further that Zn sulfate increased the nuclear factor kappa-B (NF-κB) DNA binding activity and activated JNK. During our TEM investigations, no effect on the appearance of the A549 cells exposed to CaSO(4) compared to the nonexposed cells was observed, and in our experiments, only one CaSO(4) particle was detected in the cytoplasm. In the case of exposure to Zn sulfate, no particles were found in the cytoplasm of A549 cells, but we observed a concentration-dependent increase in the number and size of dark vesicles (presumably zincosomes). After exposure to PbSO(4), the A549 cells contained isolated particles as well as agglomerates both in vesicles and in the cytoplasm. Since these metal-sulfate particles are emitted into the atmosphere via the flue gas of coal-fired power stations, they may be globally abundant. Therefore, our study is of direct relevance to populations living near such power plants.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Sulfatos/toxicidade , Transporte Biológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Carvão Mineral , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Centrais Elétricas
7.
Environ Toxicol ; 27(5): 297-306, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-20803486

RESUMO

Epidemiological studies have shown that respirable exposure to emitted cement particulate matter is associated with adverse health risk for human. The underlying mechanisms, however, are poorly understood. To examine the effect of cement, nine blinded cement-related particulates (<10 µm) were assessed with regard to their induction of the proinflammatory cytokines IL-6 and IL-8 in human primary epithelial cells (pEC) from oropharyngeal mucosa as well as from nonsmall-cell lung carcinoma (non-SCLC) cells A549. It was demonstrated that the cement specimens did not act cytotoxic as assessed by the lactate dehydrogenase (LDH) assay. The basal and IL-1ß-induced IL-8 expression was suppressed, in contrast to an unchanged IL-6. At the transcript level the basal and induced IL-6 and IL-8 gene expression was not influenced by cement dust. To discover the mechanism by which cement influenced the IL-8 expression the following experiments were performed. Submerse exposure experiments have shown that the release of IL-8 was suppressed by cement dust. Furthermore, the incubation of IL-8 with cement-related specimens under cell-free condition led to a loss of immunoreactive IL-8. An immunological masking of IL-8 by free soluble components of respiratory epithelial cells was excluded. Thus, the decrease of IL-8 protein content after cement exposure seems to be a result of the adsorption of IL-8 protein to cement particles and the inhibition of IL-8 release. In conclusion, due to absent cytotoxic and inflammatory effects of cement-related specimens in both human pEC and A549 cell models it remains open how cement exposure may lead to the respiratory adverse effects in humans.


Assuntos
Materiais de Construção/toxicidade , Interleucina-8/metabolismo , Material Particulado/toxicidade , Poluentes Atmosféricos/toxicidade , Linhagem Celular Tumoral , Poeira , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Mucosa/metabolismo
8.
Dent Mater ; 38(12): 1886-1899, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36210220

RESUMO

OBJECTIVES: The aim was to evaluate the release of particles from dental materials during wet and dry grinding and test their effects on human lung epithelia cells in-vitro. METHODS: Four dental restorative materials were used: two composites [Ceram.x® universal (Dentsply Sirona) and Filtek™ Supreme XTE (3 M)], one ceramic [VITABLOCS® Mark II (VITAy)] and a ceramic-resin material [Lava™ Ultimate (3 M)]. Material samples were ground to powder under standardized wet and dry conditions in an isolated dental room. During grinding, the particle concentrations were measured with LAS and CPC. Baseline values were measured before grinding. The particles' size was evaluated using DLS and SEM. Water was used as control. The cytotoxicity and inflammatory response of the lung cells (A549) after exposure to different concentrations (1, 3, 10, 30, 100, 300 µg/mL) of the generated dust were analyzed with LDH, WST-1 and ELISA. RESULTS: LAS and CPC revealed a high concentration of particles< 10 µm and< 1 µm respectively, into the air. Particles showed high tendency to agglomerate. DLS showed particle size distribution between 150 nm and 18 µm independently of the material composition. All materials induced significant effects (p < 0.05) on the cell membrane integrity and viability of the A549 cells. Only the ceramic particles showed a significant increase in hydroxyl radical formation at low concentrations (p < 0.05), for both wet and dry conditions. All materials except ceramic, induced a significant release of IL-8 in A549 cells at 300 µg / mL (p < 0.05). SIGNIFICANCE: Wet and dry grinding of dental materials result in release of ultrafine and fine particulate matter into the air. The in-vitro findings on the cellular response of lung cells to generated dust indicate a potential risk for human health due inhalation of the released particles. The use of water-cooling seems to be beneficial resulting in reduced release of particles compared to dry grinding.


Assuntos
Poeira , Pulmão , Humanos , Poeira/análise , Tamanho da Partícula , Células Epiteliais , Água
9.
Chem Res Toxicol ; 24(9): 1460-75, 2011 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-21761924

RESUMO

Airborne particulate matter (PM) of varying size and composition is known to cause health problems in humans. The iron oxide Fe(3)O(4) (magnetite) may be a major anthropogenic component in ambient PM and is derived mainly from industrial sources. In the present study, we have investigated the effects of four different size fractions of magnetite on signaling pathways, free radical generation, cytotoxicity, and genotoxicity in human alveolar epithelial-like type-II cells (A549). The magnetite particles used in the exposure experiments were characterized by mineralogical and chemical techniques. Four size fractions were investigated: bulk magnetite (0.2-10 µm), respirable fraction (2-3 µm), alveolar fraction (0.5-1.0 µm), and nanoparticles (20-60 nm). After 24 h of exposure, the A549 cells were investigated by transmission electron microscopy (TEM) to study particle uptake. TEM images showed an incorporation of magnetite particles in A549 cells by endocytosis. Particles were found as agglomerates in cytoplasm-bound vesicles, and few particles were detected in the cytoplasm but none in the nucleus. Increased production of reactive oxygen species (ROS), as determined by the 2',7'-dichlorfluorescein-diacetate assay (DCFH-DA), as well as genotoxic effects, as measured by the cytokinesis block-micronucleus test and the Comet assay, were observed for all of the studied fractions after 24 h of exposure. Moreover, activation of c-Jun N-terminal kinases (JNK) without increased nuclear factor kappa-B (NF-κB)-binding activity but delayed IκB-degradation was observed. Interestingly, pretreatment of cells with magnetite and subsequent stimulation with the pro-inflammatory cytokine tumor necrosis factor-alpha (TNFα) led to a reduction of NF-κB DNA binding compared to that in stimulation with TNFα alone. Altogether, these experiments suggest that ROS formation may play an important role in the genotoxicity of magnetite in A549 cells but that activation of JNK seems to be ROS-independent.


Assuntos
Óxido Ferroso-Férrico/toxicidade , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Pulmão/citologia , Mutagênicos/toxicidade , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Material Particulado/toxicidade
10.
Anticancer Res ; 41(4): 1849-1858, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33813390

RESUMO

BACKGROUND/AIM: Epidemiological studies showed an increased risk of developing laryngeal head and neck squamous cell carcinoma (HNSCC) for employees working in the construction business. This suggested a causal link between exposure to cement particles and development of HNSCC but data were missing. MATERIALS AND METHODS: We established an Organisation for Economic Co-operation and Development (OECD) guideline 487-conform micronucleus assay (MNA) using oropharyngeal mucosa-derived primary epithelial cells (OPCs) ex vivo. OPCs from healthy mucosa of 52 donors were cultured in vitro and incubated with serial concentrations of two common cement particles. Mitomycin C was used as a soluble positive control, and TiO2 and DQ12 were used as negative and positive particle controls. Bi-nucleated cells were counted and the mitotic index (MI) was determined. Subsequently, micronuclei-containing bi-nucleated cells (MN+) were counted. RESULTS: Cement particles, in concentrations not significantly reducing ex vivo proliferation according to mitotic index, dose-dependently increased micronuclei formation. CONCLUSION: Through the establishment of an OECD guideline 487 conform MNA, we demonstrate the mutagenic effects of cement on human OPCs.


Assuntos
Materiais de Construção/toxicidade , Poeira , Células Epiteliais/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mucosa Bucal/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epiteliais/patologia , Feminino , Humanos , Neoplasias Laríngeas/induzido quimicamente , Neoplasias Laríngeas/patologia , Masculino , Testes para Micronúcleos , Mucosa Bucal/patologia , Cultura Primária de Células , Medição de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço/induzido quimicamente , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
11.
Nanomaterials (Basel) ; 11(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199005

RESUMO

The use of nanomaterials incorporated into plastic products is increasing steadily. By using nano-scaled filling materials, thermoplastics, such as polyethylene (PE), take advantage of the unique properties of nanomaterials (NM). The life cycle of these so-called nanocomposites (NC) usually ends with energetic recovery. However, the toxicity of these aerosols, which may consist of released NM as well as combustion-generated volatile compounds, is not fully understood. Within this study, model nanocomposites consisting of a PE matrix and nano-scaled filling material (TiO2, CuO, carbon nano tubes (CNT)) were produced and subsequently incinerated using a lab-scale model burner. The combustion-generated aerosols were characterized with regard to particle release as well as compound composition. Subsequently, A549 cells and a reconstituted 3D lung cell culture model (MucilAir™, Epithelix) were exposed for 4 h to the respective aerosols. This approach enabled the parallel application of a complete aerosol, an aerosol under conditions of enhanced particle deposition using high voltage, and a filtered aerosol resulting in the sole gaseous phase. After 20 h post-incubation, cytotoxicity, inflammatory response (IL-8), transcriptional toxicity profiling, and genotoxicity were determined. Only the exposure toward combustion aerosols originated from PE-based materials induced cytotoxicity, genotoxicity, and transcriptional alterations in both cell models. In contrast, an inflammatory response in A549 cells was more evident after exposure toward aerosols of nano-scaled filler combustion, whereas the thermal decomposition of PE-based materials revealed an impaired IL-8 secretion. MucilAir™ tissue showed a pronounced inflammatory response after exposure to either combustion aerosols, except for nanocomposite combustion. In conclusion, this study supports the present knowledge on the release of nanomaterials after incineration of nano-enabled thermoplastics. Since in the case of PE-based combustion aerosols no major differences were evident between exposure to the complete aerosol and to the gaseous phase, adverse cellular effects could be deduced to the volatile organic compounds that are generated during incomplete combustion of NC.

12.
Neurotherapeutics ; 18(2): 1360-1370, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33449304

RESUMO

Oropharyngeal dysphagia is prevalent in age-related neurological disorders presenting with impaired efficacy and safety of swallowing due to a loss of muscle force and sensory deficits. Stimulating the oropharynx with capsaicin that mediates Substance P release is an emerging pharmacological treatment option which needs further scientific evidence. Our aim was to comprehensively evaluate the effect of capsaicin on biochemical, neurophysiological, and biomechanical parameters of swallowing function. In a randomized study on healthy individuals, the impact of orally administered capsaicinoids at different dosages and application durations in comparison to non-carbonated water was evaluated. Time course and magnitude of salivary Substance P increase were monitored. Magnetoencephalography was used to detect cortical swallowing network alterations. Modifications in swallowing biomechanics were measured applying high-resolution pharyngeal manometry. Capsaicinoids at 10 µmol/L improved swallowing efficacy as seen by a significant increase of pharyngeal contractile integral and upper esophageal sphincter activation and relaxation times in manometry. Significant improvement of precision in a challenging swallow task accompanied by a reduction in swallowing-related submental electromyographic power was observed with capsaicinoids preconditioning at 10 µmol/L over 5 min, but not with continuous stimulation. The cortical activation pattern remained unchanged after any intervention. A significant increase of salivary Substance P was not detected with 10 µmol/L but with 50 µmol/L and lasted for 15 min after application. Capsaicinoids mediate dose-dependent Substance P release and positively alter swallowing biomechanics in healthy subjects. The results provide supportive evidence for the value of natural capsaicinoids to improve swallowing function.


Assuntos
Capsaicina/farmacologia , Córtex Cerebral/efeitos dos fármacos , Deglutição/efeitos dos fármacos , Esfíncter Esofágico Superior/efeitos dos fármacos , Faringe/efeitos dos fármacos , Fármacos do Sistema Sensorial/farmacologia , Substância P/efeitos dos fármacos , Adulto , Fenômenos Biomecânicos , Capsaicina/análogos & derivados , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Deglutição/fisiologia , Eletromiografia , Esfíncter Esofágico Superior/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Magnetoencefalografia , Masculino , Manometria , Faringe/fisiologia , Distribuição Aleatória , Saliva/química , Saliva/efeitos dos fármacos , Substância P/metabolismo , Adulto Jovem
13.
Environ Int ; 151: 106449, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33611105

RESUMO

BACKGROUND: Increased use of renewable resources like sustainably produced wood in construction or for all sorts of long-lived products is considered to contribute to reducing society's carbon footprint. However, as a natural, biological material, wood and wood products emit specific volatile organic compounds (VOCs). Therefore, the evaluation of possible health effects due to wood emissions is of major interest. OBJECTIVES: We investigated the effects of an exposure to multiple wood-related VOCs on asthma development. METHODS: A murine asthma model was used to evaluate possible allergic and inflammatory effects on the lung after short- or long-term and perinatal exposure to pinewood or oriented strand board (OSB). In addition, wood-related VOCs were measured within the German prospective mother-child cohort LINA and their joint effect on early wheezing or asthma development in children until the age of 10 was estimated by Bayesian kernel machine regression (BKMR) stratifying also for family history of atopy (FHA). RESULTS: Our experimental data show that neither pinewood nor OSB emissions even at high total VOC levels and a long-lasting exposure period induce significant inflammatory or asthma-promoting effects in sensitized or non-sensitized mice. Moreover, an exposure during the vulnerable time window around birth was also without effect. Consistently, in our mother-child cohort LINA, an exposure to multiple wood-related VOCs during pregnancy or the first year of life was not associated with early wheezing or asthma development in children independent from their FHA. CONCLUSION: Our findings indicate that emissions from wood and wood products at levels commonly occurring in the living environment do not exert adverse effects concerning wheezing or asthma development.


Assuntos
Asma , Compostos Orgânicos Voláteis , Animais , Asma/induzido quimicamente , Teorema de Bayes , Camundongos , Estudos Prospectivos , Compostos Orgânicos Voláteis/toxicidade , Madeira
14.
Dent Mater ; 36(8): 1009-1018, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32507540

RESUMO

OBJECTIVES: This study evaluated the release of bisphenol A (BPA) in wastewater after grinding of resin composites and tested three filtration materials. METHODS: Three resin composites (Ceram X, Filtek Supreme XTE and Core-X flow) were used. Samples (5mm×2mm, n=10) were prepared using a metal mold and were polymerized for 20s according to manufacturers' instructions. A dental unit was disconnected from wastewater circulation and composite samples were ground under standardized procedures (200,000rpm; 90s). Wastewater was collected in glass bottles. Water samples were collected as control by performing the same procedure without grinding resin composite. All samples were stored at 7°C for 6 months to simulate storage. Then they were analyzed by HPLC-FLD. Three filtration materials (Zeosorb, Katalox Light and Catalytic Carbon) were used for water treatment to remove BPA. BPA-water solutions were prepared; corresponding to the highest amount released by the resin composites. These solutions were analyzed before and after filtration by HPLC-FLD and their efficacy (%) was calculated. RESULTS: BPA was detected in all composite solutions: Ceram X and Filtek Supreme XTE showed similar findings (p>0.05) which were significantly higher than the control (p<0.001) and Core-X flow (p=0.001). The efficacy of the filtration materials was: Katalox Light (5.09%)

Assuntos
Materiais Dentários , Águas Residuárias , Compostos Benzidrílicos , Resinas Compostas , Teste de Materiais , Fenóis
15.
Mutat Res ; 649(1-2): 15-27, 2008 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-17980648

RESUMO

In the course of standardisation of the in vitro micronucleus test for analysis of effluents according to ISO, a national round-robin study was organised by the German Federal Institute of Hydrology (BfG), involving 10 laboratories of private companies, universities and public authorities. The micronucleus assay was performed with the permanently growing Chinese hamster lung fibroblast cell line V79. All participants tested four encoded samples from one municipal and one industrial wastewater treatment plant with and without metabolic activation by S9-mix. Two of these samples were spiked in advance with defined concentrations of the clastogenic substances cyclophosphamide and mitomycin C, respectively. Cyclophosphamide and ethyl methanesulfonate were used as positive controls. The defined assessment criterion for genotoxicity was the lowest dilution of a sample that does not show any significant induction of micronuclei. Cytotoxicity was judged by determining the cell-survival index, i.e. the percentage growth rate of the cells compared with the corresponding negative controls. As supplementary qualitative criteria, the mitotic index and the proliferation index were assessed. All participants successfully established the method within a few weeks and generated viable test results in time. The two non-genotoxic samples were detected as negative by 90% (with S9-mix) and 95% (without S9-mix) of the participants. The mitomycin C-spiked wastewater sample (expected to be positive without S9-mix supplementation) was correctly judged as positive by all laboratories. The cyclophosphamide-spiked sample (expected to be positive with S9-mix addition) was evaluated correctly as genotoxic by 80% of the laboratories. A post-test analysis found evidence that the false negative results were due to technical failure, but not of a methodological nature. In 94% of all tests the sample LID values (lowest ineffective dilution=dilution stage of the sample in the test at which a statistically significant increase in the micronucleus rate was not detectable any more) varied by no more than one dilution step around the median LID value. The survival index was proven to be a robust measure for estimation of toxicity. This round-robin study is the first inter-laboratory comparison of the in vitro micronucleus test using wastewater samples. The test system is intended to complement the already DIN- and ISO-standardised bacterial tests, i.e. the umu-test and the Ames plate-incorporation assay. The data provide evidence that the robust and practicable in vitro micronucleus test is suitable as a routine method for wastewater testing.


Assuntos
Ciclofosfamida/toxicidade , Metanossulfonato de Etila/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Aberrações Cromossômicas/induzido quimicamente , Testes para Micronúcleos/métodos , Testes para Micronúcleos/normas , Eliminação de Resíduos Líquidos
16.
Toxicol Environ Chem ; 100(4): 373-394, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31534295

RESUMO

High urban atmospheric pollution is caused by economic and industrial growth, especially in developing countries. The objective of this study was to assess possible relationships between in vitro effects on human alveolar epithelial cells of source-related dust types collected at Sulaimani City (Iraq), and to determine their mineralogical and chemical composition. A passive sampler was used to collect dust particles at a rural, an industrial and an urban sampling site during July and August 2014. The samples were size-fractionated by a low-pressure impactor to obtain respirable dust with aerodynamic diameters of less than 10 µm. The dust was mainly composed of quartz and calcite. Chrysotile fibres (white asbestos) were also found at the urban site. Dust from the industrial and urban sites triggered cytotoxic and genotoxic effects in the cells, whereas only minor effects were observed for the sample from the rural site.

17.
Pathog Glob Health ; 111(1): 7-22, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28093045

RESUMO

BACKGROUND: With modern information technology, an overwhelming amount of data is available on different aspects of societies. Our research investigated the feasibility of using secondary data sources to get an overview of determinants of health and health outcomes in different population strata of Cape Town, a large city of South Africa. METHODS: The methodological approach of secondary-data analysis was similar in the different disciplines: Biological Anthropology, Public Health, Environmental Health, Mental Health, Palliative Care, Medical Psychology and Sociology at the University of Freiburg and Public Health at the University of Cape Town. The teams collected information on Cape Town through Internet searches and published articles. The information was extracted, analyzed, condensed, and jointly interpreted. RESULTS: Data show the typical picture of a population in epidemiological and demographic transition exposed to often difficult social, mental, and physical environmental conditions. Comparison between low and higher socioeconomic districts demonstrated that the former had higher air pollution, poorer water quality, and deficient sanitary conditions in addition to sub-optimal mental health services and palliative care. CONCLUSION: Although important information gaps were identified, the data draw attention to critical public health interventions required in poor health districts, and to motivate for pro-equity policies.


Assuntos
Nível de Saúde , Saúde Pública , Saúde da População Urbana/estatística & dados numéricos , Poluição do Ar/análise , Criança , Pré-Escolar , Interpretação Estatística de Dados , Saúde Ambiental/estatística & dados numéricos , Estudos de Viabilidade , Feminino , Acessibilidade aos Serviços de Saúde , Pesquisa sobre Serviços de Saúde/métodos , Humanos , Lactente , Mortalidade , Fatores de Risco , Determinantes Sociais da Saúde , Fatores Socioeconômicos , África do Sul/epidemiologia
18.
Environ Sci Pollut Res Int ; 22(22): 18017-30, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26169816

RESUMO

In the present study, in vitro toxicity as well as biopersistence and photopersistence of four artificial sweeteners (acesulfame, cyclamate, saccharine, and sucralose) and five antibiotics (levofloxacin, lincomycin, linezolid, marbofloxacin, and sarafloxacin) and of their phototransformation products (PTPs) were investigated. Furthermore, antibiotic activity was evaluated after UV irradiation and after exposure to inocula of a sewage treatment plant. The study reveals that most of the tested compounds and their PTPs were neither readily nor inherently biodegradable in the Organisation for Economic Co-operation and Development (OECD)-biodegradability tests. The study further demonstrates that PTPs are formed upon irradiation with an Hg lamp (UV light) and, to a lesser extent, upon irradiation with a Xe lamp (mimics sunlight). Comparing the nonirradiated with the corresponding irradiated solutions, a higher chronic toxicity against bacteria was found for the irradiated solutions of linezolid. Neither cytotoxicity nor genotoxicity was found in human cervical (HeLa) and liver (Hep-G2) cells for any of the investigated compounds or their PTPs. Antimicrobial activity of the tested fluoroquinolones was reduced after UV treatment, but it was not reduced after a 28-day exposure to inocula of a sewage treatment plant. This comparative study shows that PTPs can be formed as a result of UV treatment. The study further demonstrated that UV irradiation can be effective in reducing the antimicrobial activity of antibiotics, and consequently may help to reduce antimicrobial resistance in wastewaters. Nevertheless, the study also highlights that some PTPs may exhibit a higher ecotoxicity than the respective parent compounds. Consequently, UV treatment does not transform all micropollutants into harmless compounds and may not be a large-scale effluent treatment option.


Assuntos
Antibacterianos/análise , Antibacterianos/toxicidade , Processos Fotoquímicos , Edulcorantes/análise , Edulcorantes/toxicidade , Água/química , Antibacterianos/química , Antibacterianos/metabolismo , Biodegradação Ambiental , Células HeLa , Células Hep G2 , Humanos , Esgotos/química , Edulcorantes/química , Edulcorantes/metabolismo , Raios Ultravioleta , Gerenciamento de Resíduos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
19.
Anticancer Res ; 24(2B): 631-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15161005

RESUMO

Malignant gliomas tend to recur in the vast majority of cases. Recurrent gliomas may arise from vital tumor cells present in this zone around the resection margin. It appears promising to combine tumor resection with local chemotherapy using an antineoplastic, but non-toxic agent. Taurolidine exerts a selective antineoplastic effect by induction of programmed cell death and has anti-angiogenic activity. Fibrin sealant is completely degradable and firmly adheres to brain tissue, suggesting that it would provide a suitable matrix for taurolidine delivery--a Taurolidine-Fibrin-Sealant-Matrix (TFM)--in the local treatment of brain tumors. The potential of local delivery of taurolidine out of a fibrin sealant matrix was investigated. Taurolidine could be suspended homogeneously in both the thrombin and the procoagulant protein components of the fibrin sealant. The fibrin sealant matrix was a suitable carrier for the suspension of taurolidine at a concentration that ensured the release of therapeutically effective amounts of the drug over a period of 2 weeks in vitro. The antineoplastic action of taurolidine was not affected by embedding in the fibrin sealant matrix. The described drug delivery system may be suitable for local taurolidine treatment of brain tumors following complete or partial resection or of tumors that are non-resectable because of their location.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Adesivo Tecidual de Fibrina/administração & dosagem , Glioblastoma/tratamento farmacológico , Taurina/análogos & derivados , Taurina/administração & dosagem , Tiadiazinas/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacocinética , Neoplasias Encefálicas/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Química Farmacêutica , Preparações de Ação Retardada , Difusão , Adesivo Tecidual de Fibrina/química , Adesivo Tecidual de Fibrina/farmacocinética , Glioblastoma/metabolismo , Humanos , Modelos Biológicos , Taurina/química , Taurina/farmacocinética , Tiadiazinas/química , Tiadiazinas/farmacocinética
20.
Chem Biol Interact ; 142(3): 285-96, 2003 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-12453666

RESUMO

The aim of this study was to investigate the chemoprotective effects of water and garden cress juices towards benzo(a)pyrene (B(a)P)-induced DNA damage using the single cell gel electrophoresis (SCGE)/Hep G2 test system. This experimental model combines the advantages of the SCGE assay with that of human derived cells possessing inducible phase I and phase II enzymes. Treatment of Hep G2 cells with small amounts of water cress or garden cress juice (0.1-1.25 microl/ml) and B(a)P reduced the genotoxic effect of the latter in a dose-dependent manner. Contrary to the results with the juices, unexpected synergistic effects were observed with benzyl isothiocyanate (BITC, 0.6 microM), a breakdown product of glucotropaeolin contained abundantly in garden cress. Although these concentrations of BITC did not cause DNA damage per se, at higher concentrations (> or = 2.5 microM), the compound caused a pronounced dose-dependent DNA damage by itself. With phenethyl isothiocyanate (PEITC), the breakdown product of gluconasturtin contained in water cress, no synergistic effects with B(a)P were seen; however, significant induction of DNA damage was observed when the cells were exposed to the pure compound at concentrations > or = 5 microM. In experiments with (+/-)-anti-benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE, 5.0 microM), the ultimate genotoxic metabolite of B(a)P, and the juices, only moderate protective effects were seen indicating that detoxification of BPDE is not the main mechanism behind the protective effect of the juices against B(a)P-induced DNA damage. In conclusion, our findings show that garden and water cress juices are highly protective against B(a)P-induced DNA damage in human derived cells and that their effects can not be explained by their isothiocyanate contents.


Assuntos
Brassicaceae , Dano ao DNA , Lepidium sativum , Benzo(a)pireno/toxicidade , Linhagem Celular , Humanos , Isotiocianatos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Verduras/química
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