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1.
Sensors (Basel) ; 24(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339721

RESUMO

The use of radar technology for non-contact measurement of vital parameters is increasingly being examined in scientific studies. Based on a systematic literature search in the PubMed, German National Library, Austrian Library Network (Union Catalog), Swiss National Library and Common Library Network databases, the accuracy of heart rate and/or respiratory rate measurements by means of radar technology was analyzed. In 37% of the included studies on the measurement of the respiratory rate and in 48% of those on the measurement of the heart rate, the maximum deviation was 5%. For a tolerated deviation of 10%, the corresponding percentages were 85% and 87%, respectively. However, the quantitative comparability of the results available in the current literature is very limited due to a variety of variables. The elimination of the problem of confounding variables and the continuation of the tendency to focus on the algorithm applied will continue to constitute a central topic of radar-based vital parameter measurement. Promising fields of application of research can be found in particular in areas that require non-contact measurements. This includes infection events, emergency medicine, disaster situations and major catastrophic incidents.


Assuntos
Radar , Taxa Respiratória , Frequência Cardíaca/fisiologia , Processamento de Sinais Assistido por Computador , Algoritmos , Sinais Vitais , Monitorização Fisiológica/métodos
2.
Environ Sci Pollut Res Int ; 28(20): 25069-25080, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-29934830

RESUMO

Herein, we report a novel paper-based electrochemical sensor for on-site detection of sulphur mustards. This sensor was conceived combining office paper-based electrochemical sensor with choline oxidase enzyme to deliver a sustainable sensing tool. The mustard agent detection relies on the evaluation of inhibition degree of choline oxidase, which is reversibly inhibited by sulphur mustards, by measuring the enzymatic by-product H2O2 in chronoamperometric mode. A nanocomposite constituted of Prussian Blue nanoparticles and Carbon Black was used as working electrode modifier to improve the electroanalytical performances. This bioassay was successfully applied for the measurement of a sulphur mustard, Yprite, obtaining a detection limit in the millimolar range (LOD = 0.9 mM). The developed sensor, combined with a portable and easy-to-use instrumentation, can be applied for a fast and cost-effective detection of sulphur mustards.


Assuntos
Técnicas Biossensoriais , Gás de Mostarda , Nanopartículas , Técnicas Eletroquímicas , Eletrodos , Peróxido de Hidrogênio , Limite de Detecção
3.
Toxicol Lett ; 320: 80-86, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31809884

RESUMO

In vitro cell culture experiments are highly important techniques to accelerate drug discovery, conduct safety testing and reduce the need for animal studies. Therefore, automatization may help to enhance the technical precision, reduce external (including operator's) influence on the data and thus improve reliability. Prior to application in scientific studies, validation of automated systems is absolutely necessary. In this study we present the validation of two combined automated pipetting systems to conduct toxicity studies in HaCaT cells consisting of cell seeding, noxious agent exposure and several assays to assess cell survival, apoptosis and interleukin production. After initial validation of pipetting accuracy, we compared homogeneity after automated seeding to plates seeded by expert laboratory technicians. Moreover, automated dispensing of a potentially unstable noxious agent was analyzed in terms of speed and consistency. We found a 2 % technical imprecision for the cell survival assay and 4.5-6 % for the other assays, bioluminescent and ELISA techniques. Thus, we could demonstrate the excellent technical precision of our assays. In a final step, we found that intraday variations, though acceptable, were much larger than technical variations and had to assume an intraday biological variability between different wells of the same experimental group.


Assuntos
Automação Laboratorial/normas , Substâncias para a Guerra Química/toxicidade , Gás de Mostarda/toxicidade , Técnicas de Cultura de Tecidos/normas , Testes de Toxicidade/normas , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Teste de Materiais , Necrose
4.
Toxicol Lett ; 314: 172-180, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31404593

RESUMO

Vesicants cause a multitude of cutaneous reactions like erythema, blisters and ulcerations. After exposure to sulfur mustard (SM) and related compounds, patients present dermal symptoms typically known for chemicals categorized as skin sensitizer (e.g. hypersensitivity and flare-up phenomena). However, although some case reports led to the assumption that SM and other alkylating compounds represent sensitizers, a comprehensive investigation of SM-triggered immunological responses has not been conducted so far. Based on a well-structured system of in chemico and in vitro test methods, the Organization for Economic Co-operation and Development (OECD) established procedures to categorize agents on their skin sensitizing abilities. In this study, the skin sensitizing potential of SM and three related alkylating agents (AAs) was assessed following the OECD test guidelines. Besides SM, investigated AAs were chlorambucil (CHL), nitrogen mustard (HN3) and 2-chloroethyl ethyl sulfide (CEES). The methods are described in detail in the EURL ECVAM DataBase service on ALternative Methods to animal experimentation (DB-ALM). In accordance to OECD recommendations, skin sensitization is a pathophysiological process starting with a molecular initiating step and ending with the in vivo outcome of an allergic contact dermatitis. This concept is called adverse outcome pathway (AOP). An AOP links an adverse outcome to various key events which can be assayed by established in chemico and in vitro test methods. Positive outcome in two out of three key events indicates that the chemical can be categorized as a skin sensitizer. In this study, key event 1 "haptenation" (covalent modification of epidermal proteins), key event 2 "activation of epidermal keratinocytes" and key event 3 "activation of dendritic cells" were investigated. Covalent modification of epidermal proteins measured by using the DPRA-assay provided distinct positive results for all tested substances. Same outcome was seen in the KeratinoSens assay, investigating the activation of epidermal keratinocytes. The h-CLAT assay performed to determine the activation of dendritic cells provided positive results for SM and CEES but not for CHL and HN3. Altogether, following OECD requirements, our results suggest the classification of all investigated substances as skin sensitizers. Finally, a tentative AOP for SM-induced skin sensitization is suggested.


Assuntos
Substâncias para a Guerra Química/toxicidade , Irritantes/toxicidade , Gás de Mostarda/toxicidade , Testes de Irritação da Pele/normas , Pele/efeitos dos fármacos , Biomarcadores/metabolismo , Substâncias para a Guerra Química/classificação , Clorambucila/classificação , Clorambucila/toxicidade , Guias como Assunto , Humanos , Irritantes/classificação , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Queratinócitos/metabolismo , Células de Langerhans/efeitos dos fármacos , Células de Langerhans/imunologia , Células de Langerhans/metabolismo , Mecloretamina/classificação , Mecloretamina/toxicidade , Gás de Mostarda/análogos & derivados , Gás de Mostarda/classificação , Medição de Risco , Pele/imunologia , Pele/metabolismo
5.
JMIR Mhealth Uhealth ; 7(8): e13516, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31429420

RESUMO

BACKGROUND: The Syria crisis has forced more than 4 million people to leave their homeland. As a result, in 2016, an overwhelming number of refugees reached Germany. In response to this, it was of utmost importance to set up refugee camps and to provide humanitarian aid, but a health surveillance system was also implemented in order to obtain rapid information about emerging diseases. OBJECTIVE: The present study describes the effects of using digital paper and pen (DPP) technology on the speed, sequence, and behavior of epidemiological documentation in a refugee camp. METHODS: DPP technology was used to examine documentation speed, sequence, and behavior. The data log of the digital pens used to fill in the documentation was analyzed, and each pen stroke in a field was recorded using a timestamp. Documentation time was the difference between first and last stroke on the paper, which includes clinical examination and translation. RESULTS: For three months, 495 data sets were recorded. After corrections had been made, 421 data sets were considered valid and subjected to further analysis. The median documentation time was 41:41 min (interquartile range 29:54 min; mean 45:02 min; SD 22:28 min). The documentation of vital signs ended up having the strongest effect on the overall time of documentation. Furthermore, filling in the free-text field clinical findings or therapy or measures required the most time (mean 16:49 min; SD 20:32 min). Analysis of the documentation sequence revealed that the final step of coding the diagnosis was a time-consuming step that took place once the form had been completed. CONCLUSIONS: We concluded that medical documentation using DPP technology leads to both an increase in documentation speed and data quality through the compliance of the data recorders who regard the tool to be convenient in everyday routine. Further analysis of more data sets will allow optimization of the documentation form used. Thus, DPP technology is an effective tool for the medical documentation process in refugee camps.


Assuntos
Documentação/normas , Refugiados/estatística & dados numéricos , Fatores de Tempo , Documentação/métodos , Documentação/tendências , Alemanha , Humanos , Campos de Refugiados/estatística & dados numéricos , Síria/etnologia
6.
Toxicol Lett ; 312: 109-117, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31048000

RESUMO

Sulfur mustard (SM) is a highly toxic chemical warfare agent, which produces blisters after skin contact. Treatment of SM-induced adverse health effects, such as cutaneous blistering, ulceration, and inflammation remains a challenging task. Antidotes or specific therapeutic measures are lacking. Some drugs (e.g. cyclooxygenase (COX) inhibitors) exhibited beneficial effects after SM poisoning in vivo. However, in vitro studies that evaluate and compare the potency of COX inhibitors are missing. In the presented study, non-specific (acetylsalicylic acid, ibuprofen, diclofenac, indomethacin, and piroxicam), COX-2-specific (celecoxib and parecoxib) inhibitors and COX-independent drugs (paracetamol and tofacitinib) were compared regarding anti-inflammatory and cytoprotective effects after SM exposure in post-exposure treatment settings. Normal human epidermal keratinocytes (NHEK) were used as a surrogate model. Prostaglandin E2 (PGE2) formation, a direct indicator for COX activity, was determined by ELISA. Changes in pro-inflammatory cytokine levels after SM exposures were assessed by quantitative determination of 27 inflammatory cytokines using a multiplex method. Cytotoxicity was determined using an XTT viability assay. The results demonstrated that SM highly increased PGE2 production and release of pro-inflammatory cytokines, predominantly IL-6, IL-8 and TNF-α. In general, all COX inhibitors and paracetamol were able to reduce the PGE2 formation, while tofacitinib, an inhibitor of Janus kinase, had no influence on PGE2 levels. In addition, IL-6, IL-8, and TNF-α formation were also inhibited, but sometimes independently of PGE2. The COX-2 specific celecoxib was identified as the most potent drug to reduce IL-6, IL-8 and TNF-α formation after SM exposures in vitro. However, cell viability was not improved significantly by any of the investigated drugs in our experiments.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Citocinas/metabolismo , Inflamação/induzido quimicamente , Queratinócitos/efeitos dos fármacos , Gás de Mostarda/toxicidade , Linhagem Celular , Citocinas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/metabolismo
7.
Biosens Bioelectron ; 129: 15-23, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30682684

RESUMO

The synthesis and employment of volatile toxic compounds as chemical weapons with a large-scale destructive power has introduced a new insidious threat over the last century. In this framework, the development of wearable sensing tools represents a critical point within the security field, in order to provide early alarm systems. Herein, a novel wearable electrochemical biosensor was developed for the rapid and on-site detection of mustard agents. Since a chemical attack is typically carried out by spraying these volatile agents into air, the sensor was designed in order to be able to measure mustard agents directly in the aerosol phase, further than in the liquid phase. The electrodes were screen-printed onto a filter paper support, which allowed to harness the porosity of paper to pre-load all the needed reagents into the cellulose network, and hence to realise an origami-like and reagent-free device. Mustard agent detection was carried out by monitoring their inhibitory effects toward the choline oxidase enzyme, through the amperometric measurement of the enzymatic by-product hydrogen peroxide. A carbon black/Prussian blue nanocomposite was used as a bulk-modifier of the conductive graphite ink constituting the working electrode, allowing for the electrocatalysis of the hydrogen peroxide reduction. After having verified the detecting capability toward a mustard agent simulant, the applicability of the resulting origami-like biosensor was demonstrated for the rapid and real-time detection of real sulfur mustard, obtaining limits of detection equal to 1 mM and 0.019 g·min/m3 for liquid and aerosol phase, respectively.


Assuntos
Técnicas Biossensoriais/instrumentação , Substâncias para a Guerra Química/análise , Gás de Mostarda/análise , Dispositivos Eletrônicos Vestíveis , Aerossóis/análise , Alcaligenes/enzimologia , Oxirredutases do Álcool/química , Técnicas Eletroquímicas/instrumentação , Enzimas Imobilizadas/química , Desenho de Equipamento , Humanos , Limite de Detecção , Papel
8.
Chem Biol Interact ; 298: 80-85, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30391637

RESUMO

Although its first military use in Ypres was 100 years ago, no causal therapy for sulfur mustard (SM) intoxications exists so far. To improve the therapeutic options for the treatment of SM intoxications, we developed a co-culture of keratinocytes (HaCaT cells) and immunocompetent cells (THP-1 cells) to identify potential substances for further research. Here, we report on the influence of necrosulfonamide (NSA) on the course of a SM intoxication in vitro. The cells were challenged with 100, 200 and 300 µM SM and after 1 h treated with NSA (1, 5, 10 µM). NSA was chosen for its known ability to inhibit necroptosis, a specialized pathway of programmed necrosis. However, in our settings NSA showed only mild effects on necrotic cell death after SM intoxication, whereas it had an immense ability to prevent apoptosis. Furthermore, NSA was able to reduce the production of interleukin-6 and interleukin-8 at certain concentrations. Our data highlight NSA as a candidate compound to address cell death and inflammation in SM exposure.


Assuntos
Acrilamidas/farmacologia , Gás de Mostarda/toxicidade , Substâncias Protetoras/farmacologia , Sulfonamidas/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Técnicas de Cocultura , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Necrose/tratamento farmacológico
9.
Toxicol Lett ; 293: 45-50, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29155286

RESUMO

The chemical warfare agent sulfur mustard (SM) can cause long-term health effects that may occur even years after a single exposure. The underlying pathophysiology is unknown, but epigenetic mechanisms are discussed as feasible explanation. "Epigenetics" depicts regulation of gene function without affecting the DNA sequence itself. DNA-methylation and covalent histone modifications (methylation or acetylation) are regarded as important processes. In the present in vitro study using early endothelial cells (EEC), we analyzed SM-induced DNA methylation over time and compared results to an in vivo skin sample that was obtained approx. one year after an accidental SM exposure. EEC were exposed to low SM concentrations (0.5 and 1.0µM). DNA methylation and histone acetylation (H3-K9, H3-K27, H4-K8) or histone di-methylation (H3-K9, H3-K27, H3-K36) were investigated 24h after exposure, and after 2 or 4 additional cell passages. The human skin sample was assessed in parallel. SM had only some minor effects on histone modifications. However, a significant and pronounced increase of DNA methylation was detected in the late cell passages as well as in the skin sample. Our results indicate that SM does indeed cause epigenetic modifications that appear to persist over time.


Assuntos
Substâncias para a Guerra Química/toxicidade , Epigênese Genética/efeitos dos fármacos , Gás de Mostarda/toxicidade , Acetilação , Linhagem Celular , Substâncias para a Guerra Química/envenenamento , Metilação de DNA/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Histonas/metabolismo , Humanos , Metilação , Gás de Mostarda/envenenamento , Projetos Piloto , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Pele/citologia , Pele/patologia
10.
Toxicol Lett ; 293: 2-8, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28916288

RESUMO

Skin affections after sulfur mustard (SM) exposure include erythema, blister formation and severe inflammation. An antidote or specific therapy does not exist. Anti-inflammatory compounds as well as substances counteracting SM-induced cell death are under investigation. In this study, we investigated the benzylisoquinoline alkaloide berberine (BER), a metabolite in plants like berberis vulgaris, which is used as herbal pharmaceutical in Asian countries, against SM toxicity using a well-established in vitro approach. Keratinocyte (HaCaT) mono-cultures (MoC) or HaCaT/THP-1 co-cultures (CoC) were challenged with 100, 200 or 300mM SM for 1h. Post-exposure, both MoC and CoC were treated with 10, 30 or 50µM BER for 24h. At that time, supernatants were collected and analyzed both for interleukine (IL) 6 and 8 levels and for content of adenylate-kinase (AK) as surrogate marker for cell necrosis. Cells were lysed and nucleosome formation as marker for late apoptosis was assessed. In parallel, AK in cells was determined for normalization purposes. BER treatment did not influence necrosis, but significantly decreased apoptosis. Anti-inflammatory effects were moderate, but also significant, primarily in CoC. Overall, BER has protective effects against SM toxicity in vitro. Whether this holds true should be evaluated in future in vivo studies.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antídotos/farmacologia , Apoptose/efeitos dos fármacos , Berberina/farmacologia , Substâncias para a Guerra Química/toxicidade , Queratinócitos/efeitos dos fármacos , Gás de Mostarda/toxicidade , Adenilato Quinase/metabolismo , Linhagem Celular , Células Cultivadas , Técnicas de Cocultura , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Queratinócitos/patologia , Necrose
11.
Toxicol Lett ; 293: 133-139, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28919489

RESUMO

The hygroscopic zinc chloride (ZnCl2) is often used to generate smoke screens. Severe adverse pulmonary health effects have been associated with inhalation of ZnCl2 smokes. The underlying molecular toxicology is not known. Recent studies have shown that the Transient Receptor Potential Channel A1 (TRPA1) is important for sensing toxic chemicals. TRPA1 was shown to be activated by Zn2+ which was linked to pain and inflammation. In the present study, we investigated whether TRPA1 activation contributes to ZnCl2-mediated toxicity in vitro. HEK wildtype (HEK-wt), TRPA1 overexpressing HEK (HEK-A1) and A549 lung cells, endogenously expressing TRPA1, were exposed to ZnCl2. Changes of intracellular calcium levels [Ca2+]i and cell viability were assessed after ZnCl2 exposure in all cell types, without or with TRPA1 inhibition. ZnCl2 increased [Ca2+]i through TRPA1 channels in a complex manner in both HEK-A1 and A549 cells while HEK-wt did not respond to ZnCl2. There was no difference in toxicity between HEK-wt and HEK-A1 cells after ZnCl2 exposure. Inhibition of TRPA1 did not influence toxicity in all investigated cells. Thus, our in vitro results support the assumption that TRPA1 does not primarily mediate toxicity of ZnCl2 and does probably not represent a therapeutic target to abate ZnCl2 toxicity.


Assuntos
Cloretos/toxicidade , Canal de Cátion TRPA1/agonistas , Compostos de Zinco/toxicidade , Células A549 , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Técnicas de Patch-Clamp , Fumaça
12.
Dent Mater ; 33(1): 54-62, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27836116

RESUMO

OBJECTIVE: An increment layering technique in a thickness of 2mm or less has been the standard to sufficiently convert (co)monomers. Bulk fill resin composites were developed to accelerate the restoration process by enabling up to 4mm thick increments to be cured in a single step. The aim of the present study is to investigate the effect of layer thickness on the elution of components from bulk fill composites. METHODS: The composites ELS Bulk fill, SDR Bulk fill and Venus Bulkfill were polymerized according to the instruction of the manufacturers. For each composite three groups with four samples each (n=4) were prepared: (1) samples with a layer thickness of 2mm; (2) samples with a layer thickness of 4mm and (3) samples with a layer thickness of 6mm. The samples were eluted in methanol and water for 24h and 7 d. The eluates were analyzed by gas chromatography/mass spectrometry (GC/MS). RESULTS: A total of 11 different elutable substances have been identified from the investigated composites. Following methacrylates showed an increase of elution at a higher layer thickness: TEGDMA (SDR Bulk fill, Venus Bulk fill), EGDMA (Venus Bulk fill). There was no significant difference in the elution of HEMA regarding the layer thickness. The highest concentration of TEGDMA was 146µg/mL for SDR Bulk fill at a layer thickness of 6mm after 7 d in water. The highest HEMA concentration measured at 108µg/mL was detected in the methanol eluate of Venus Bulk fill after 7 d with a layer thickness of 6mm. SIGNIFICANCE: A layer thickness of 4mm or more can lead to an increased elution of some bulk fill components, compared to the elution at a layer thickness of 2mm.


Assuntos
Resinas Compostas , Metacrilatos , Teste de Materiais , Polimerização
13.
Chem Biol Interact ; 262: 12-18, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27923644

RESUMO

Sulfur mustard (SM), a chemical warfare agent, causes DNA alkylation, which is believed to be the main cause of its toxicity. SM DNA adducts are commonly used to verify exposure to this vesicant. However, the required analytical state-of-the-art mass-spectrometry methods are complex, use delicate instruments, are not mobile, and require laboratory infrastructure that is most likely not available in conflict zones. Attempts have thus been made to develop rapid detection methods that can be used in the field. The analysis of SM DNA adducts (HETE-G) by immunodetection is a convenient and suitable method. For a diagnostic assessment, HETE-G levels must be determined in relation to the total DNA in the sample. Total DNA can be easily visualized by the use of fluorescent DNA dyes. This study examines whether SM and related compounds affect total DNA staining, an issue that has not been investigated before. After pure DNA was extracted from human keratinocytes (HaCaT cells), DNA was exposed to different S- and N-alkylating agents. Our experiments revealed a significant, dose-dependent decrease in the fluorescence signal of fluorescent dye-stained DNA after exposure to alkylating agents. After mass spectrometry and additional fluorescence measurements ruled out covalent modifications of ethidium bromide (EthBr) by SM, we assumed that DNA crosslinks caused DNA condensation and thereby impaired access of the fluorescent dyes to the DNA. DNA digestion by restriction enzymes restored fluorescence, a fact that strengthened our hypothesis. However, monofunctional agents, which are unable to crosslink DNA, also decreased the fluorescence signal. In subsequent experiments, we demonstrated that protons produced during DNA alkylation caused a pH decrease that was found responsible for the reduction in fluorescence. The use of an appropriate buffer system eliminated the adverse effect of alkylating agents on DNA staining with fluorescent dyes. An appropriate buffer system is thus crucial for DNA quantification with fluorescent dyes in the presence of alkylating compounds.


Assuntos
Alquilantes/química , Substâncias para a Guerra Química/química , DNA/química , Corantes Fluorescentes/química , Gás de Mostarda/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Adutos de DNA/análise , Etídio/química , Humanos , Espectrometria de Massas em Tandem
14.
Toxicol Lett ; 249: 22-8, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27033775

RESUMO

Poisoning by organophosphorus compounds (OP) still poses a major medical challenge. Diagnosis of clinical signs of OP poisoning is still the most important parameter for the initiation of specific treatment. However, in case of unspecific signs and of delayed onset of cholinergic crisis a rapid, reliable and on-site analysis of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity would be of great value. Recently the ChE check mobile, a CE-certified ready to use kit for the determination of whole blood AChE and BChE activities, was developed. Here, we evaluated whole blood AChE and BChE reference values with samples taken from 181 male and 61 female volunteers and analyzed them on-site with the ChE check mobile test kit. The analysis of the data revealed a large inter-individual variability (BChE>AChE), only a small sex difference for AChE but a significant difference for BChE activities. The now available normal range values enable an evaluation of determined AChE and BChE activities in case of suspected exposure to OP nerve agents and pesticides. However, the large inter-individual variability of AChE and BChE activities calls for the determination of pre-exposure values in specific subpopulations in order to enable the diagnosis of low-level OP exposure.


Assuntos
Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Compostos Organofosforados/toxicidade , Kit de Reagentes para Diagnóstico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
15.
Dent Mater ; 32(2): 127-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26719129

RESUMO

OBJECTIVES: Bleaching treatments can affect release of components from conventional composites. In this continuing study the influence of two different bleaching gels on the elution of bulk-fill composite components was investigated. METHODS: The composites Tetric EvoCeram(®) Bulk Fill, QuiXFil™ and X-tra fil were treated with the bleaching gels Opalescence PF 15% (PF 15%) for 5 h and PF 35% (PF 35%) for 30 min and then stored in methanol and water for 24 h and 7 d. The eluates were analyzed by gas chromatography/mass spectrometry (GC/MS). Unbleached specimens were used as control group. RESULTS: A total of 7 different elutable substances have been identified from the investigated composites after bleaching-treatment. Three of them were methacrylates: 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and trimethylolpropane trimethacrylate (TMPTMA). Compared to the unbleached controls an increase in elution after PF 15%-treatment of following compounds was found: HEMA (Tetric EvoCeram(®) Bulk Fill), TEGDMA (QuiXFil™, X-tra fil) and 4-N,N-dimethylaminobenzoic acid butyl ethoxy ester (DMABEE) (Tetric EvoCeram(®) Bulk Fill, QuiXFil™, X-tra fil). Following compounds showed a reduction in elution after PF 35%-treatment compared to controls: TEGDMA (QuiXFil™) and DMABEE (Tetric EvoCeram(®) Bulk Fill). The highest concentration of HEMA was 0.22 mmol/l (Tetric EvoCeram(®) Bulk Fill, methanol, 7 d, PF 15%), the highest concentration of TEGDMA was 0.3 mmol/l (X-tra fil, water, 7 d, PF 15%) and the highest concentration of DMABEE was 0.05 mmol/l (QuiXFil™, water, 7 d, PF 35%). SIGNIFICANCE: PF 15% and PF 35% can lead to reduced and/or increased elution of some bulk-fill components, compared to unbleached bulk-fill composites.


Assuntos
Resinas Compostas/química , Peróxidos/química , Polivinil/química , Clareadores Dentários/química , Ureia/análogos & derivados , Ácido 4-Aminobenzoico/química , Cromatografia Gasosa , Combinação de Medicamentos , Espectrometria de Massas , Teste de Materiais , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Ureia/química
16.
Toxicol Lett ; 244: 35-43, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26361990

RESUMO

Sulfur mustard (SM) is a chemical warfare agent causing blistering, inflammation and ulceration of the skin. Thiol compounds such as glutathione (GSH) and N-acetylcysteine (NAC) have been suggested as potential antidotes. We investigated SM toxicity in a human keratinocyte cell line (HaCaT) and used GSH and NAC to counteract its cytotoxic effects. Cells were treated with 1, 5 or 10mM GSH or NAC and exposed to 30, 100 or 300µM SM. Different treatment regimens were applied to model extra- and intra-cellular GSH/NAC effects on SM toxicity. Necrosis, apoptosis and interleukin-6 and -8 levels were determined 24h post-exposure. Necrosis and apoptosis increased with SM dose. Interleukin-6 and -8 production peaked at 100µM and decreased at 300µM probably due to reduced ability for interleukin biosynthesis. Intracellular GSH/NAC diminished necrosis induced by 100µM SM. Extracellular GSH/NAC protected against necrosis and apoptosis induced by 100 and 300µM SM. Interleukin-6 and -8 production, induced by 100µM SM was reduced by GSH/NAC. However, low-dose GSH/NAC treatment of cells exposed to 300µM SM led to increased interleukin production. Thus, moderately poisoned cells are mostly responsible for SM-induced secretion of pro-inflammatory cytokines. GSH and NAC treatment can reduce SM-induced toxic effects. Protective effects were more pronounced by extracellular GSH or NAC administration. Rescue of severely poisoned cells may result in a strong secretion of pro- inflammatory cytokines. In summary, thiol compounds such as GSH or NAC constitute a promising approach to improve the therapy for SM injury. Additional intervention to prevent adverse effects of interleukin production might be beneficial.


Assuntos
Acetilcisteína/farmacologia , Antídotos/farmacologia , Substâncias para a Guerra Química/toxicidade , Glutationa/farmacologia , Queratinócitos/efeitos dos fármacos , Gás de Mostarda/toxicidade , Compostos de Sulfidrila/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Citoproteção , Relação Dose-Resposta a Droga , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Queratinócitos/metabolismo , Queratinócitos/patologia , Necrose , Fatores de Tempo
17.
Clin Oral Investig ; 20(8): 2113-2121, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26707337

RESUMO

OBJECTIVES: Polymerization of resin-based composites (RBCs) is incomplete. The aim of the present study was to determine whether a longer curing time than recommended by the manufacturer influences the amount of released composite components of RBCs. MATERIALS AND METHODS: The composites Clearfil AP-X and els extra low shrinkage were polymerized for six different curing times: 4, 10, 20, 40, 100, and 200 s. Light curing time recommended by the manufacturer for both composites is 20 s. Subsequently, samples were eluted in methanol and water for 1, 3, and 7 days and analyzed by gas chromatography/mass spectrometry (GC/MS). RESULTS: For Clearfil AP-X ethylene glycol dimethacrylate (EGDMA), diethylene glycol dimethacrylate (DEGDMA), triethylene glycol dimethacrylate (TEGDMA), 2-hydroxy-4-methoxybenzophenone (HMBP), camphorquinone (CQ) and 2,6-di-tert-butyl-4-methylphenol (BHT) were detected in methanol. In the aqueous eluate, only TEGDMA was detected. In els extra low shrinkage, HMBP, BHT, and CQ were detected in methanol. CONCLUSION: Increasing the curing time compared to recommendation of the manufacturer reduces the release of most composite components. This could result in less exposure to human due to these substances. CLINICAL RELEVANCE: Methacrylates are classified as potential allergens. An increasing number of dentists and patients show allergic reaction to methacrylates. Therefore, a reduced elution of composite components is an advantage.


Assuntos
Resinas Compostas/química , Materiais Dentários/química , Cura Luminosa de Adesivos Dentários , Cromatografia Gasosa , Espectrometria de Massas , Teste de Materiais , Metacrilatos/química , Polimerização , Fatores de Tempo
18.
Chem Biol Interact ; 219: 143-50, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-24892517

RESUMO

Alkylating agents (e.g. sulfur and nitrogen mustards) cause a variety of cell and tissue damage including wound healing disorder. Migration of endothelial cells is of utmost importance for effective wound healing. In this study we investigated the effects of chlorambucil (a nitrogen mustard) on early endothelial cells (EEC) with special focus on cell migration. Chlorambucil significantly inhibited migration of EEC in Boyden chamber and wound healing experiments. Cell migration is linked to cytoskeletal organization. We therefore investigated the distribution pattern of the Golgi apparatus as a marker of cell polarity. Cells are polarized under control conditions, whereas chlorambucil caused an encircling perinuclear position of the Golgi apparatus, indicating non-polarized cells. ROS are discussed to be involved in the pathophysiology of alkylating substances and are linked to cell migration and cell polarity. Therefore we investigated the influence of ROS-scavengers (α-linolenic acid (ALA) and N-acetylcysteine (NAC)) on the impaired EEC migration. Both substances, in particular ALA, improved EEC migration. Notably ALA restored cell polarity. Remarkably, investigations of ROS and RNS biomarkers (8-isoprostane and nitrotyrosine) did not reveal a significant increase after chlorambucil exposure when assessed 24h post exposure. A distinct breakdown of mitochondrial membrane potential (measured by TMRM) that recovered under ALA treatment was observed. In conclusion our results provide compelling evidence that the alkylating agent chlorambucil dramatically impairs directed cellular migration, which is accompanied by perturbations of cell polarity and mitochondrial membrane potential. ALA treatment was able to reconstitute cell polarity and to stabilize mitochondrial potential resulting in improved cell migration.


Assuntos
Acetilcisteína/farmacologia , Antineoplásicos Alquilantes/metabolismo , Movimento Celular/fisiologia , Clorambucila/metabolismo , Endotélio Vascular/metabolismo , Ácido alfa-Linolênico/farmacologia , Animais , Antineoplásicos Alquilantes/toxicidade , Movimento Celular/efeitos dos fármacos , Polaridade Celular/fisiologia , Clorambucila/toxicidade , Células Endoteliais , Endotélio Vascular/citologia , Sequestradores de Radicais Livres/farmacologia , Imuno-Histoquímica , Potencial da Membrana Mitocondrial , Camundongos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo
19.
J Colloid Interface Sci ; 413: 127-32, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24183440

RESUMO

The present contribution presents a microemulsion system containing cosmetic oil and sugar surfactant and the enzyme diisopropyl fluorophosphatase (DFPase) as active agent for the decontamination of human skin. The bicontinuous structure and the physical properties of the microemulsion are characterized by dynamic light scattering and small angle neutron scattering. The DFPase from the squid Loligo vulgaris is catalyzing the hydrolysis of highly toxic organophosphates. The effect of the enzyme on the structure of the microemulsion is investigated. Moreover, the enzyme/microemulsion system is also studied with respect to its activity using nuclear magnetic resonance spectroscopy leading to promising results. A fast decomposition of the nerve agent sarin is achieved.


Assuntos
Emulsões , Óleos/química , Compostos Organofosforados/química , Pele , Tensoativos/química , Estrutura Molecular
20.
Chem Biol Interact ; 206(3): 435-43, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24091052

RESUMO

Recent news from Syria on a possible use of chemical warfare agents made the headlines. Furthermore, the motivation of terrorists to cause maximal harm shifts these agents into the public focus. For incidents with mass casualties appropriate medical countermeasures must be available. At present, the most important threats arise from nerve agents and sulfur mustard. At first, self-protection and protection of medical units from contamination is of utmost importance. Volatile nerve agent exposure, e.g. sarin, results in fast development of cholinergic crisis. Immediate clinical diagnosis can be confirmed on-site by assessment of acetylcholinesterase activity. Treatment with autoinjectors that are filled with 2mg atropine and an oxime (at present obidoxime, pralidoxime, TMB-4 or HI-6) are not effective against all nerve agents. A more aggressive atropinisation has to be considered and more effective oximes (if possible with a broad spectrum or a combination of different oximes) as well as alternative strategies to cope with high acetylcholine levels at synaptic sites should be developed. A further gap exists for the treatment of patients with sustained cholinergic crisis that has to be expected after exposure to persistent nerve agents, e.g. VX. The requirement for long-lasting artificial ventilation can be reduced with an oxime therapy that is optimized by using the cholinesterase status for guidance or by measures (e.g. scavengers) that are able to reduce the poison load substantially in the patients. For sulfur mustard poisoning no specific antidote is available until now. Symptomatic measures as used for treatment of burns are recommended together with surgical or laser debridement. Thus, huge amounts of resources are expected to be consumed as wound healing is impaired. Possible depots of sulfur mustard in tissues may aggravate the situation. More basic knowledge is necessary to improve substantially therapeutic options. The use of stem cells may provide a new and promising option.


Assuntos
Substâncias para a Guerra Química/envenenamento , Antídotos/administração & dosagem , Atropina/administração & dosagem , Guerra Química , Substâncias para a Guerra Química/química , Inibidores da Colinesterase/envenenamento , Descontaminação , Humanos , Gás de Mostarda/envenenamento , Compostos Organotiofosforados/envenenamento , Oximas/administração & dosagem , Sarina/envenenamento
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