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1.
Ann Med Surg (Lond) ; 85(7): 3611-3614, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37427245

RESUMO

The stylohyoid ligament begins when the styloid process extends from the petrous temporal bone in a thin bony protrusion. Eagle's syndrome (ES) is a condition related to either calcification of the calcifying the stylohyoid ligament or elongating styloid process The incidence of symptomatic ES is 0.16%, and it is more common in women. The reported study diagnosed ES and treated it surgically through transoral approach styloidectomy. Case presentation: A 39-year-old man who is a farmer and a driver was presented with complaints of ongoing, excruciating discomfort in the back of his left ear. Before the exam, he took a variety of drugs, various drugs 2 years without receiving a definitive diagnosis. Axial, coronal, and sagittal computed tomography scans of both petrous bones were analyzed, and the results showed aberrant styloid process elongation and calcification of the stylohyoid ligament. Discussion: ES, shares many symptoms with other regional illnesses. Physicians frequently misdiagnose cases of ES and treat them without providing a conclusive diagnosis or treatment. Conclusion: ES diagnosis can be difficult for otolaryngologists and primary care providers due to its similarity with other regional illnesses. However, surgical intervention can result in consistent and significant symptomatic improvement when correctly diagnosed. The case presented in the report was successfully diagnosed as ES and treated surgically through transoral approach styloidectomy.

2.
J Sustain Cem Based Mater ; 9(6): 350-370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34136311

RESUMO

Substitution of cement clinker with suitable excess materials from other processes is an effective way to reduce CO2 emissions of cement production. Moreover, specific properties of the resulting mortar or concrete can be designed with different clinker replacement materials and their mixing ratios. In this study, bottom and fly ashes from six biomass power plants with different power scales and various flue-gas treatment strategies were admixed to mortars, whose properties (influence of water requirement and final compressive strength) were then assessed in the laboratory by following industrial standard procedures. Results reveal that fly ash from a cyclone of a medium-scale combustor burning Miscanthus straw amended with 2 wt % Ca(OH)2 (to prevent slagging during combustion) turned out to be well suited as a clinker replacement material, even boosting final compressive strength of the mortar. Wood-chip bottom ashes and fly ash from a cyclone exhibited acceptable results, whereas fly ash from electrostatic precipitators (ESPs) and baghouse filters lowered final compressive strength of the mortar when admixed. The scale of the power plant is positively correlated with final compressive strength in the case of ESPs. Cenospheres, typical fly ash particles present in cyclone ash, seem to have a positive effect on water-to-binder ratio and final compressive strength. In contrast, potassium salts, which are most abundant in ash from ESPs and baghouse filters, appear to have a negative influence on these properties. Grinding of the biomass ashes to a typical Portland cement fineness had a positive effect on mortar quality. All fly ashes had high contents of Cd, and baghouse filter ash contained As in amounts about four times the Swiss limit value for cement of 30 ppm; only bottom ash and cyclone ash from Miscanthus exhibited concentrations below respective limit values for all critical trace elements. To assess the immobilization potential of contaminating elements during the cement hardening process, blended mortars were crushed and subjected to multistep leaching, followed by subsequent analysis of the leachates by atomic absorption spectroscopy. Immobilization of Cd by the mortar was particularly effective. Our results indicate that fly ash from wood-chip combustion is most suitable as an amendment to cement when it was trapped by a cyclone rather than by the ESPs or baghouse filters.

3.
Chem Res Toxicol ; 33(5): 1039-1054, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-31507156

RESUMO

One of the challenges in using in vitro data to understand the potential risks of engineered nanomaterials (ENMs) is that results often differ or are even contradictory among studies. While it is recognized that numerous factors can influence results produced by nanobioassays, there has not yet been a consistently used conceptual framework to identify key sources of variability in these assays. In this paper, we use cause-and-effect analysis to systematically describe sources of variability in four key in vitro nanobioassays: the 2',7'-dichlorofluorescein assay, an enzyme-linked immunosorbent assay for measuring interleukin-8, a flow cytometry assay (Annexin V/propidium iodide), and the Comet assay. These assays measure end points that can occur in cells impacted by ENMs through oxidative stress, a principle mechanism for ENM toxicity. The results from this analysis identify control measurements to test for potential artifacts or biases that could occur during conduct of these assays with ENMs. Cause-and-effect analysis also reveals additional measurements that could be performed either in preliminary experiments or each time the assay is run to increase confidence in the assay results and their reproducibility within and among laboratories. The approach applied here with these four assays can be used to support the development of a broad range of nanobioassays.


Assuntos
Ensaio Cometa , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Fluorometria , Nanotecnologia , Fluoresceínas/química , Corantes Fluorescentes/química , Humanos , Interleucina-8/análise , Reprodutibilidade dos Testes
4.
Fuel (Lond) ; 2582019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32523161

RESUMO

Bottom and fly ash samples from six biomass power plants with different power scales and various flue gas treatment strategies were collected and analyzed in regard to their mineralogical composition, and their bulk major and trace element contents, all of which are of concern for regulations on biomass ash for further utilization. Furthermore, individual ash particles were investigated by scanning electron microscopy to characterize their physicochemical microstructures. Thermal behavior of wood-pellet ash, i.e. decomposition processes and mineral transformations during combustion, was indicated by thermogravimetric analysis and X-ray diffraction. Results reveal extensive variation of physicochemical features across the different ash types: wood-chip fly ash from electrostatic precipitators mainly consisted of water-soluble salts, whereas wood-chip fly ash from cyclones contained predominantly cenospheres (hollow spherical fly ash particles) and higher heavy metal concentrations. In addition, the fuel type and admixture had influences on ash compositions; some fuels like Miscanthus straw require a liming agent such as calcium hydroxide to be admixed to prevent fouling, which is then predominantly found in the ash. Furthermore, boiler size had an influence on fly ash composition. Cadmium concentrations were elevated in some fly ash samples at levels of concern for further utilization, whereas concentrations of troublesome Cr(VI) were below the detection limit for all investigated ash samples. Other contaminating elements such as Ni, Pb and Zn were variable but below limit values. Results clearly show that the nature of biomass ash calls for careful analyses prior to further application as, e.g., cement clinker replacement material.

5.
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.

6.
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.

7.
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
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