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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124724, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38941755

RESUMO

Many studies show that ortho-phenylenediamine (OPD) produces an oxidized fluorescent product when exposed to an oxidizing agent that enables the direct or indirect fluorescence detection of a range chemical and biochemical analytes. However, there is no report on this unique optical behavior for other two isomers of phenylenediamine. This study demonstrates that a simple hydrothermal treatment of para-phenylenediamine (PPD) in the presence of sulfuric acid results in the formation of fluorescent N, S-doped carbon dots (CDs) with triple functionalities including the reduction of Au3+ into gold nanoparticles (AuNPs), the stabilization of the produced AuNPs, and the determination of Au3+ concentration through an intrinsic ratiometric fluorescence signal. In the presence of Au3+, the blue emission of CDs at 437 nm quenched, and a green emission at 540 nm emerged. The linear concentration range for the determination of Au3+ was 20 nM-16 µM with a detection limit of 16 nM. Additionally, the dual emissive CDs-AuNPs hybrid probe showed potential for the indirect fluorescence ratiometric determination of cysteine and sulfide ions. The linear concentration range for cysteine and sulfide ions were 0.25-8 µM and 0.1-6 µΜ, with detection limits of 0.095 µM and 0.041 µM, respectively. Accordingly, CDs were applied to detect Au3+ and S2- in real water samples. Moreover, the synthesized CDs showed no cytotoxicity for HeLa cells up to 300 µg mL-1, as determined by the MTT assay. Therefore, their potential for intracellular imaging of Au3+ in living cells was also investigated.

2.
Cureus ; 16(4): e58054, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38738072

RESUMO

Allergy to hair products is an increasingly common issue among people given the exposure to these products on a daily basis. Allergic reactions could be in the form of delayed-type contact dermatitis or the form of immediate-type hypersensitivity reactions. Hair products contain many ingredients and chemicals that patients may have allergies to, but common allergens are hair dyes, fragrances, persulfate salts, ammonium thioglycolate, coconut fatty acid derivatives, and acrylates. Allergy to hair dye is the most common followed by other allergens such as fragrances and persulfate salts. We discussed testing for hair dye allergy along with suggestions for alternative hair dyes that patients may use. Allergy to topical scalp medications is also seen in patients using those products. Allergy to topical minoxidil is seen more often due to the increased use of minoxidil sprays and foams among patients to increase hair growth. We will discuss in this review the diagnosis and alternatives for patients with minoxidil allergy. Hairdressers are at higher risk of allergy to hair products compared to the general population due to prolonged exposure to allergens and specific measures should be implemented to minimize the hazards of exposure.

3.
Environ Sci Technol ; 58(13): 5921-5931, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38512777

RESUMO

Identifying transformed emerging contaminants in complex environmental compartments is a challenging but meaningful task. Substituted para-phenylenediamine quinones (PPD-quinones) are emerging contaminants originating from rubber antioxidants and have been proven to be toxic to the aquatic species, especially salmonids. The emergence of multiple PPD-quinones in various environmental matrices and evidence of their specific hazards underscore the need to understand their environmental occurrences. Here, we introduce a fragmentation pattern-based nontargeted screening strategy combining full MS/All ion fragmentation/neutral loss-ddMS2 scans to identify potential unknown PPD-quinones in different environmental matrices. Using diagnostic fragments of m/z 170.0600, 139.0502, and characteristic neutral losses of 199.0633, 138.0429 Da, six known and three novel PPD-quinones were recognized in air particulates, surface soil, and tire tissue. Their specific structures were confirmed, and their environmental concentration and composition profiles were clarified with self-synthesized standards. N-(1-methylheptyl)-N'-phenyl-1,4-benzenediamine quinone (8PPD-Q) and N,N'-di(1,3-dimethylbutyl)-p-phenylenediamine quinone (66PD-Q) were identified and quantified for the first time, with their median concentrations found to be 0.02-0.21 µg·g-1 in tire tissue, 0.40-2.76 pg·m-3 in air particles, and 0.23-1.02 ng·g-1 in surface soil. This work provides new evidence for the presence of unknown PPD-quinones in the environment, showcasing a potential strategy for screening emerging transformed contaminants in the environment.


Assuntos
Fenilenodiaminas , Quinonas , Fenilenodiaminas/química , Benzoquinonas , Solo
4.
J Hazard Mater ; 465: 133427, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38185090

RESUMO

Substituted para-phenylenediamine quinones (PPD-quinones) are a class of emerging contaminants frequently detected in the aqueous environment. One of them, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q), was found to cause acute toxicities to aquatic species at extremely low environmental levels. The ubiquitousness and ecotoxicity of such pollutants underscore the importance of their transformation and elimination. In this work, we demonstrated effective removals of five PPD-quinones in aqueous environments under UV irradiation, with up to 94% of 6PPD-Q eliminated after a 40-min treatment. By applying high-resolution mass spectrometry (HRMS) non-targeted screening in combination with isotope labeling strategies, a total of 22 transformation products (TPs) were identified. Coupling with the time-based dynamic patterns, potential transformation mechanisms were identified as an •OH-induced photocatalysis reaction involving bond cleavage, hydroxylation, and oxidation. Computational toxicity assessment predicted lower aquatic toxicity of the TPs than their parent PPD-quinones. Our results in parallel evidenced an obvious reduction of PPD-quinones accompanied by the presence of their TPs in the effluent after UV disinfection in real municipal wastewater. This work builds a comprehensive understanding of the fate, transformation products, and related toxicological characteristics of emerging PPD-quinone contaminants in the aqueous environment.


Assuntos
Benzoquinonas , Fenilenodiaminas , Quinonas , Poluentes Químicos da Água , Fotólise , Raios Ultravioleta , Poluentes Químicos da Água/química , Cinética
5.
Toxicol Ind Health ; 39(7): 388-397, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37243687

RESUMO

Para-phenylenediamine (PPD) is a derivative of benzene used as an ingredient in dyes, a photographic developing agent, and a component of engineered polymers. The carcinogenicity of PPD, which has been documented in several studies, may be related to its toxic effects on different compartments of the immune system. The main goal of this research was to evaluate the mechanism of the toxicity of PPD on human lymphocytes by exploiting the accelerated cytotoxicity mechanism screening (ACMS) technique. Lymphocytes were isolated from the blood of healthy persons using a Ficoll-Paque PLUS standard method. Assessment of cell viability was carried out 12 h following treatment of human lymphocytes with 0.25-1 mM PPD. For determination of cellular parameters, isolated human lymphocytes were incubated with 1/2 the IC50 (0.4 mM), the IC50 (0.8 mM), and twice the IC50 (1.6 mM) for 2, 4, and 6 h. Half maximal inhibitory concentration (IC50) is the concentration that reduces cell viability approximately 50% following treatment. The results of this study demonstrated that PPD-associated apoptosis in human lymphocytes was mainly through the enhancement of intracellular calcium, oxidative stress, and following adverse effect on lymphocyte organelles (like mitochondria and lysosomes). Lipid peroxidation, activation of caspase-3, and stimulation of cytokines (IL2, interferon-gamma (IFN-γ), and TNF-alpha) production were also observed in PPD-treated lymphocytes. Considering the results of this study, we can suggest an association between PPD carcinogenicity and its toxic effects on different compartments of the immune system.


Assuntos
Cálcio , Linfócitos , Humanos , Espécies Reativas de Oxigênio , Apoptose
6.
Cureus ; 15(3): e36697, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37113365

RESUMO

Henna is commonly used in body arts, where it produces orange-brown color. It is often mixed with chemicals such as para-phenylenediamine (PPD) to fasten the dyeing process and produce a black color. However, PPD has many allergic and toxic effects. We present a case of henna-induced cutaneous neuritis, which is not reported before. A 27-year-old female presented to our hospital, complaining of pain in her left great toe after applying black henna. Upon examination, the proximal nail fold was inflamed, and an erythematous non-palpable tender lesion was noticed on the dorsum of the foot. The lesion had an inverted-Y shape that was confined to the course of the superficial fibular nerve. Cutaneous nerve inflammation was favored after excluding all the anatomical structures in the region. Black henna should be avoided since it contains PPD, which can be absorbed through the skin and affect the underlying cutaneous nerves.

7.
Regul Toxicol Pharmacol ; 138: 105331, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36603762

RESUMO

Hair dye products include a range of chemicals, depending on the type and color. A common primary intermediate compound used to achieve the permanent effect of hair dye is para-phenylenediamine (PPD). 4-aminobiphenyl (4-ABP) has reportedly been found as a trace contaminant (presumably from the para-phenylenediamine [PPD] ingredient) in consumer permanent hair dye. While several regulatory agencies have designated 4-ABP as a human bladder carcinogen based on evidence in humans and experimental animals, only the Office of Environmental Health Hazard Assessment (OEHHA) have established a cancer risk value for 4-ABP of 0.03 µg/day based on liver tumors developed in mice. A hypothetical dermal risk assessment was performed to estimate the bladder cancer risk associated with exposure to 4-ABP from personal use of permanent hair dye potentially containing incidental 4-ABP. Previously published laboratory analyses characterizing 4-ABP concentrations in consumer hair dyes indicate the concentrations can range from below the limit of detection to 8120 ppb. Precautionary estimates of human scalp surface area, maximum skin adherence, hair dye retention factor, and percent dermal absorption were used to estimate the daily systemic exposure doses (SEDs) from dermal application of hair dye. The estimated SEDs ranged from 0.05 to 3000 pg/day. A margin of safety (MOS) was calculated as the ratio of the NSRL to the SED and ranged from 10 to 570,000. The results of this study suggest that there is no indication of increased risk of bladder cancer in humans from exposure to 4-ABP in consumer hair dye, especially as it is extremely unlikely that a consumer would use permanent hair dye on a daily basis (as this assessment models).


Assuntos
Tinturas para Cabelo , Neoplasias da Bexiga Urinária , Humanos , Animais , Camundongos , Tinturas para Cabelo/toxicidade , Bexiga Urinária/química , Fenilenodiaminas/toxicidade , Neoplasias da Bexiga Urinária/induzido quimicamente , Medição de Risco
8.
Environ Sci Technol ; 56(15): 10629-10637, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35834306

RESUMO

Substituted para-phenylenediamine (PPD) antioxidants have been extensively used to retard oxidative degradation of tire rubber and were found to pervade multiple environmental compartments. However, there is a paucity of research on the environmental occurrences of their transformation products. In this study, we revealed the co-occurrence of six PPD-derived quinones (PPD-Qs) along with eight PPDs in fine particulate matter (PM2.5) from two Chinese megacities, in which N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine quinone (77PD-Q) was identified and quantified for the first time. Prevalent occurrences of these emerging PPD-Qs were found in Taiyuan (5.59-8480 pg/m3) and Guangzhou (3.61-4490 pg/m3). Significantly higher levels of PPDs/PPD-Qs were observed at a roadside site, implying the possible contribution of vehicle emissions. Correlation analysis implied potential consistencies in the fate of these PPD-Qs and suggested that most of them were originated from the transformation of their parent PPDs. For different subpopulation groups under different exposure scenarios, the estimated daily intakes of PPD-Qs (0.16-1.25 ng kgbw-1 day-1) were comparable to those of their parent PPDs (0.19-1.41 ng kgbw-1 day-1), suggesting an important but overlooked exposure caused by novel PPD-Qs. Given the prolonged exposure of these antioxidants and their quinone derivatives to traffic-relevant occupations, further investigations on their toxicological and epidemiological effects are necessary.


Assuntos
Antioxidantes , Material Particulado , Benzoquinonas , Material Particulado/análise , Fenilenodiaminas/análise , Prevalência
9.
Environ Toxicol ; 37(7): 1803-1813, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35363429

RESUMO

Several studies demonstrate that para-phenylenediamine (PPD) is often added to permanent oxidative hair dyes. Sub-chronic topical exposure to PPD in male rats damages their testicular function; however, little is known about the effects of PPD exposure on the female reproductive system, especially on oocyte quality. In this study, we found that PPD can affect the meiotic capacity of oocytes and their fertilization potential. In particular, PPD can damage the spindle/chromosome structure and prevent oocytes from developing and maturing normally. Furthermore, PPD exposure compromised the dynamics of cortical granules and their component, ovastacin. In addition to the protein level of Juno, the sperm receptors on the egg membrane, were substantially impaired in PPD-administered oocytes, thus leading to fertilization failure. Finally, we found that PPD exposure resulted in abnormal mitochondrial function, which led to oocyte degeneration, apoptosis, and increased ROS levels. Altogether, our study illustrates that mitochondrial dysfunction and redox perturbation are the major causes of the poor quality of oocytes exposed to PPD.


Assuntos
Meiose , Mitocôndrias , Oócitos , Fenilenodiaminas , Animais , Feminino , Tinturas para Cabelo/toxicidade , Masculino , Mitocôndrias/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Fenilenodiaminas/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo
10.
Arch Toxicol ; 96(1): 153-165, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773126

RESUMO

Para-phenylenediamine (PPD) is one of the most used chemicals in oxidative hair dyes. However, its use has been associated with adverse effects on health, including contact dermatitis and other systemic toxicities. Novel PPD derivatives have been proposed as a safer replacement for PPD. This can be achieved if these molecules minimally permeate the skin and/or are easily metabolised by enzymes in the skin (e.g., N-acetyltransferase-1 (NAT-1)) into innocuous compounds before gaining systemic entry. This study investigated the detoxification pathway mediated by NAT-1 enzymes on 6 synthesized PPD analogues (namely, P1-P6) with different chemical properties, to study the role of functional groups on detoxification mechanisms in HaCaT skin cells. These compounds were carefully designed with different chemical properties (whereby the ortho position of PPD was substituted by nucleophile and electrophile groups to promote N-acetylation reactions, metabolism and clearance). Compounds P2-P4 N-acetylated at 54-49 nmol/mg/min, which is 1.6 times higher than N-acetylation of PPD, upregulated NAT-1 activity from 8-7% at 50 µM to 22-11% at 100 µM and showed 4 times higher rate of elimination (k equal to 0.141 ± 0.016-0.124 ± 0.01 h-1) and 3 times faster rate of clearance (0.172 ± 0.007-0.158 ± 0.005 h-1mgprotein-1) than PPD (0.0316 ± 0.0019 h-1, 0.0576 ± 0.003 h-1mg protein-1, respectively). The data suggest that nucleophile substituted compounds detoxify at a faster rate than PPD. Our metabolic and detoxification mechanistic studies revealed significantly higher rates of N-acetylation, NAT-1 activity and higher detoxification of P2-P4 in keratinocytes, suggesting the importance of nucleophilic groups at the ortho position in PPD to reduce toxicity of aniline-based dyes on human skin cells.


Assuntos
Dermatite Alérgica de Contato , Tinturas para Cabelo , Arilamina N-Acetiltransferase , Tinturas para Cabelo/química , Tinturas para Cabelo/metabolismo , Tinturas para Cabelo/toxicidade , Humanos , Isoenzimas , Fenilenodiaminas/metabolismo , Fenilenodiaminas/toxicidade
11.
Macromol Rapid Commun ; 42(21): e2100431, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34480770

RESUMO

The hydrogels composed of decamethylcucurbit[5]uril (Me10 Q[5]) and para-phenylenediamine (p-PDA) are first reported herein. They are the first Q[5]-based supramolecular hydrogels, the formation of which is driven by portal exclusion between Me10 Q[5] and p-PDA. The composition, structure, and properties of the Me10 Q[5]/p-PDA-based hydrogels are investigated by various techniques. Since the 1D supramolecular chain forms via portal exclusion between Me10 Q[5] and p-PDA is the key to the formation of the hydrogels, any competitive species, such as metal ions, organic molecules, and amino acids, which can affect the portal exclusion, can change the behavior of the Me10 Q[5]/p-PDA-based hydrogels. Hence, the hydrogels can be used for various applications. Importantly, the results may provide a new research direction for the preparation of Q[n]-based hydrogels via portal exclusion of Q[n]s with guests.


Assuntos
Hidrogéis , Fenilenodiaminas , Íons
12.
Cureus ; 13(4): e14607, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-34079664

RESUMO

Para phenylenediamine (PPD) is a common component of hair dye as well as temporary tattoos and is a well-known cause of type 4 hypersensitivity reactions from topical exposure. While there have been several cases reported in the literature describing toxicities following ingestion, there are a paucity of reports of severe systemic disease following topical exposure. Cases of PPD ingestion have been reported to present with angioedema-like reactions, often progressing to rhabdomyolysis and renal failure. To our knowledge, there have only been two reported cases of severe reactions following topical exposure to PPD. We present a case of a 59-year-old man with topical exposure to hair dye who presented with an angioedema-like reaction shortly after topical exposure to PPD containing hair dye that rapidly progressed to rhabdomyolysis, renal failure, and eventually death.

13.
Toxics ; 9(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916218

RESUMO

Water is regarded as an important natural resource to sustain life, and its purification is an important criterion that determines its quality and usefulness. In this study, the incorporation of Fe3+ oxide onto a phenylenediamine (pPD) polymer matrix through chemical co-polymerization was prepared, and its arsenite and fluoride removal potentials at optimal conditions from aqueous solution were evaluated. The morphology and structural analysis of the synthesized Fe-doped pPD (Fe-pPD) were comparatively evaluated using the FT-IR, SEM, EDS, and XRD techniques. Fe was successfully incorporated onto pPD matrix as confirmed by different morphological characterizations. The rate of adsorption of F- and As3+ onto the Fe-pPD composite best followed the pseudo-second-order kinetic model. The experimental data for both As3+ and F- onto the Fe-pPD composite better fit the Freundlich isotherm model at different operating temperatures. Overall, the synthesized composite exhibited a strong affinity towards fluoride uptake (96.6%) than arsenite uptake (71.14%) with a maximum capacity of 6.79 (F-) and 1.86 (As3+) mg/g. Additionally, the synthesized adsorbent showed some level of antimicrobial activity against common water-borne bacterial. Therefore, the Fe-doped pPD composite has the potential ability for inorganic metal species pollutants remediation and bacterial disinfection in community-level water purification processes.

14.
Toxicol Rep ; 8: 96-105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33437652

RESUMO

para-Phenylediamine (PPD), a major component of hair dyeing ingredients, can induce allergenic sensitization and exert mutagenic, tumorigenic and cytotoxic effect. In this study, we determined the cytotoxic effect of PPD on human keratinocytes and evaluated the protective effect of Rhus semialata M. extracts (RSE) on PPD induced cytotoxicity for the first time. We observed that RSE is a strong inhibitory agent against PPD-induced toxicity in human keratinocytes. The results indicated that RSE pretreatment significantly could suppress PPD induced cytotoxic effects, including decrease of cell viability, accumulation in subG1 phase of cells, and relocation of phosphatidylserine on keratinocytes. Also, we found that PPD caused cytotoxicity was associated with mitochondrial membrane potential loss and subsequent activation of caspase and PARP degradation. However, pretreatment of RSE showed preventive activities against PPD induced mitochondrial membrane potential loss and ROS production in keratinocytes. In conclusion, the results of present study suggest that RSE was able to protect the skin from several cytotoxic effects of PPD and could be a meaningful material in many industries using PPD.

15.
Rheumatol Int ; 41(4): 795-797, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33196874

RESUMO

Hair dye (HD) and its component para-phenylenediamine (PPD) are commonly used to enhance beauty and youth. HD is associated with allergic contact reactions and the development of autoimmune phenomena. A 28-year-old woman presented to us complaining of pain and swelling affecting the small joints of the hands bilaterally lasting for 7 weeks. Laboratory evaluation was remarkable only for an increase of acute-phase reactants, while the rest of laboratory tests including serological tests for viruses, as well as immunological tests were negative or within normal limits. She noticed a close correlation between the onset of symmetrical polyarthritis and the use of HD product. Thus, after excluding other possibilities of inflammatory arthritides, the diagnosis of HD-induced arthritis was made. The patient was treated with naproxen, and after 3 weeks, she had a complete clinical response with decrease of acute-phase reactants. Thus, we review and discuss the relevant literature of cases related with the use of HD and arthritis development. This is the first described case of HD-induced arthritis. Physicians must be aware and recognize these symptoms and signs of patients exposed to HD and treat them appropriately.


Assuntos
Artrite Reumatoide/induzido quimicamente , Corantes/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Tinturas para Cabelo/efeitos adversos , Fenilenodiaminas/efeitos adversos , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Dermatite Alérgica de Contato/tratamento farmacológico , Feminino , Humanos , Hipersensibilidade/tratamento farmacológico , Naproxeno/uso terapêutico , Resultado do Tratamento
16.
Cutan Ocul Toxicol ; 39(4): 311-316, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32722942

RESUMO

BACKGROUND: Para-Phenylenediamine (PPD) is a commonly used dye intermediate in permanent hair dye formulations, and exposure to PPD has been associated with allergic contact dermatitis at certain doses. PURPOSE: Determine the concentration of PPD in a survey of self-application permanent hair dye products, and perform a quantitative risk assessment to determine the risk of skin sensitization induction following application of these products. METHODS: Consumer exposure levels (CELs) to PPD following application of hair dye products were estimated using the maximum amount of hair dye that can adhere to the surface area of the scalp, the measured concentration of PPD in the hair dye product, a retention factor, the dermal absorption of PPD, and the surface area of the scalp. CELs were calculated for various exposure scenarios, and were stratified by hair dye shade. RESULTS: All estimated CELs did not exceed the acceptable exposure level. Specifically, margins of safety ranged from 2.3 to 1534 for black dyes, 2.9 to 5031 for brown dyes, and 26 to 5031 for blonde dyes. CONCLUSIONS: Findings suggest that use of the evaluated permanent hair dyes, under the evaluated exposure scenarios, would not be expected to induce skin sensitization due to PPD exposure at concentrations ≤0.67%.


Assuntos
Dermatite Alérgica de Contato , Tinturas para Cabelo/análise , Fenilenodiaminas/análise , Qualidade de Produtos para o Consumidor , Exposição Ambiental , Humanos , Medição de Risco , Pele , Inquéritos e Questionários
17.
Micromachines (Basel) ; 11(7)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605054

RESUMO

In this study, macroporous graphene aerogels (GAs) were synthesized by chemical reduction of graphene oxide sheets and were used as a support material for in situ synthesis of conductive poly(para-phenylenediamine) (p(p-PDA)). The in situ synthesis of p(p-PDA) in GA was carried out by using a simple oxidation polymerization technique. Moreover, the prepared conductive p(p-PDA) polymers in the networks of GAs were doped with various types of acids such as hydrochloric acid (HCl), nitric acid (HNO3), sulfuric acid (H2SO4), phosphoric acid (H3PO4), respectively. The prepared GA and different acid-doped forms as GA/p(p-PDA) composites were characterized by FT-IR, TGA, and conductivity measurements. The observed FT-IR peaks at 1574 cm-1, and 1491 cm-1, for stretching deformations of quinone and benzene, respectively, confirmed the in situ synthesis of P(p-PDA) polymers within GAs. The conductivity of GAs with 2.17 × 10-4 ± 3.15 × 10-5 S·cm-1 has experienced an approximately 250-fold increase to 5.16 × 10-2 ± 2.72 × 10-3 S·cm-1 after in situ synthesis of p(p-PDA) polymers and with HCl doping. Conductivity values for different types of acid-doped GA/p(p-PDA) composites were compared with the bare p(p-PDA) and their undoped forms. Moreover, the changes in the conductivity of GA and GA/p(p-PDA) composites upon CO2 gas exposure were compared and their sensory potential in terms of response and sensitivity, along with reusability in CO2 detection, were evaluated.

18.
Xenobiotica ; 49(10): 1143-1148, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30474463

RESUMO

1. Para-phenylenediamine (PPD) is the commonest and most well-known component of hair dyes. PPD is found in more than 1000 hair dye formulations and is the most frequently used permanent hair dye component in Europe, North America and East Asia. PPD containing hair dyes have been associated with cancer and mutagenicity. Apart from that, PPD has potential toxicity which includes acute toxicity such as allergic contact dermatitis and subacute toxicity. 2. In this study, we examined the effects of the PPD composition on the skin-isolated fibroblast cells. Fibroblast cells were isolated from the skin and cell viability, reactive oxygen species (ROS) production, the collapse of mitochondrial membrane potential (MMP), lipid peroxidation (LPO), damage to the lysosome release of lactate dehydrogenase (LDH) and finally release of cytochrome c were examined following the exposure to various concentrations of PPD. 3. Our results showed that exposure to PPD increased ROS generation, LPO, the collapse of MMP, LDH release and cytochrome c release. Our results suggest that PPD can induce damage to the lysosomal membrane. 4. These results showed that PPD composition has a selective toxicity on skin fibroblasts cell and mitochondria are considered one of the goals of its toxicity.


Assuntos
Dermatite Alérgica de Contato/metabolismo , Fibroblastos/metabolismo , Tinturas para Cabelo/efeitos adversos , Fenilenodiaminas/efeitos adversos , Pele/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Dermatite Alérgica de Contato/patologia , Fibroblastos/patologia , Tinturas para Cabelo/farmacologia , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Fenilenodiaminas/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Pele/patologia
19.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-762198

RESUMO

Anaphylaxis is a sudden-onset life-threatening systemic hypersensitivity reaction. Allergens, such as foods, stinging insect venoms, and drugs, are the globally important causative factors for anaphylaxis. Para-phenylenediamine (PPD), an aromatic amine, is a well-known hair dye component that can act as a skin irritant and/or a skin sensitizer. As an allergen, PPD can induce various reactions; the most common being contact dermatitis, a delayed-type hypersensitivity reaction. Anaphylaxis or other immediate hypersensitivity reactions by hair dye contact is extremely rare, with only a few cases reported worldwide. Here, we report a case of a 63-year-old female who presented to the Emergency Department with dyspnea, rash, vomiting, and diarrhea within minutes after using a hair dye product containing PPD. Her past medical history includes urticaria of unknown cause. Her total IgE antibody level was increased to 630 kU/L. Skin prick and patch tests with the hair dye she applied at the time of anaphylaxis demonstrated an immediate reaction. An additional patch test with 25 common contact allergens showed positive reaction to PPD. This is the first case report of hair dye-induced contact anaphylaxis presenting sensitization to PPD in Korea.


Assuntos
Feminino , Humanos , Pessoa de Meia-Idade , Alérgenos , Anafilaxia , Mordeduras e Picadas , Dermatite de Contato , Diarreia , Dispneia , Serviço Hospitalar de Emergência , Exantema , Tinturas para Cabelo , Cabelo , Hipersensibilidade , Hipersensibilidade Imediata , Imunoglobulina E , Insetos , Coreia (Geográfico) , Testes do Emplastro , Pele , Urticária , Peçonhas , Vômito
20.
Polymers (Basel) ; 10(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30961313

RESUMO

The Pt elements are prepared via the redox reaction with microwave (MW) irradiation in the presence of poly(p-phenylenediamine) (PpPD) which is polymerized on XC72 carbon matrix (PpPD/XC72), behaving as reducing agent. The free primary amines of PpPD are actually converted (oxidized) to secondary ones (5,10-dihydrophenazine) after MW irradiation. Transmission electronic microscopy (TEM) micrographs reveal the prepared Pt nanoparticles are well-dispersed on the carbon matrix like commercial Pt-implanted carbon nanocomposite (Pt/C). From the residue weights of thermogravimetric analysis (TGA) thermograms of Pt-loaded PpPD/XC72 (PpPD/XC72-Pt-MW), more Pt (18.49 wt %) nanoparticles are implanted on PpPD/XC72 composite. The Pt-implanted wt % on PpPD/XC72 matrix is just slightly lower than that of commercial Pt/C (22.30 wt %). The Pt-catalyst supports of PpPD/XC72-Pt-MW illustrate typical cyclic voltammograms (C-V) of Pt-catalyst, including significant Pt⁻H oxidation and Pt⁻O reduction peaks. The electrochemical active surface area of PpPD/XC72-Pt-MW is found to be as high as 60.1 m² g-1. Max. number of electron transfer during oxygen reduction reaction (ORR) approaches 3.83 for PpPD/XC72-Pt-MW, higher than that of commercial Pt/C (3.62). Single cell based on PpPD/XC72-Pt-MW demonstrates much higher specific max. power density to be 34.6 mW cm-2 Pt, higher than that single cell prepared with commercial Pt/C electrode (30.6 mW cm-2 Pt).

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