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1.
Arch Toxicol ; 95(6): 2037-2050, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33844042

RESUMO

Parabens are widely used preservatives in cosmetics and pharmaceutical products and are approved as food additives. These chemicals have been considered safe for many years. However, the literature classifies parabens as endocrine-disrupting chemicals, and an assessment of their influence on the endocrine system and systemic toxicity is important. This study explored long-term systemic toxicity, effects on the endocrine system, and toxicokinetic behavior after repeated subcutaneous administration of butylparaben to Sprague-Dawley rats. Rats were treated with vehicle (4% Tween 80) or butylparaben at dose levels of 2, 10, and 50 mg/kg/day for 13 weeks. Assessment of systemic toxicity and endocrine-disrupting effects was based on mortality; clinical signs; body weight; food and water consumption; ophthalmological findings; urinalysis; hematology and clinical biochemistry; organ weights; necropsy and histopathological findings; regularity and length of the estrous cycle; semen quality; and toxicokinetic behavior. Female uterine weight and estrous cycle, and male semen quality indicated no estrogenic effects. Butylparaben induced local irritation at the injection site in both sexes at a dose of 50 mg/kg/day, but systemic toxicity was not observed. Therefore, the no-observed-adverse-effect level of butylparaben is set at 50 mg/kg/day in rats of both sexes. Butylparaben was without endocrine system effects at this dose. Butylparaben displays dose-dependent systemic exposure up to the maximum dose of 50 mg/kg/day and repeated administration of butylparaben for 13 weeks shows no bioaccumulation.


Assuntos
Parabenos/toxicidade , Conservantes Farmacêuticos/toxicidade , Toxicocinética , Animais , Relação Dose-Resposta a Droga , Ciclo Estral/efeitos dos fármacos , Feminino , Injeções Subcutâneas , Masculino , Nível de Efeito Adverso não Observado , Parabenos/administração & dosagem , Conservantes Farmacêuticos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Sêmen/efeitos dos fármacos , Fatores Sexuais
3.
Polymers (Basel) ; 12(8)2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32784728

RESUMO

Flexible fibers composed of a conductive material mixed with a polymer matrix are useful in wearable electronic devices. However, the presence of the conductive material often reduces the flexibility of the fiber, while the conductivity may be affected by environmental factors such as water and moisture. To address these issues, we developed a new conductive fiber by mixing carbon nanotubes (CNT) with a polyurethane (PU) matrix. A silane ((heptadecafluoro-1,1,2,2-tetra-hydrodecyl)trichlorosilane) was added to improve the strain value of the fiber from 155% to 228%. Moreover, silica aerogel particles were embedded on the fiber surface to increase the water contact angle (WCA) and minimize the effect of water on the conductivity of the fiber. As a result, the fabricated PU-CNT-silane-aerogel composite microfiber maintained a WCA of ~140° even after heating at 250 °C for 30 min. We expect this method of incorporating silane and aerogel to help the development of conductive fibers with high flexibility that are capable of stable operation in wet or humid environments.

4.
RSC Adv ; 10(30): 17724-17730, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35515599

RESUMO

Structure engineering of trivalent metal halide perovskites (MHPs) such as A3Sb2X9 (A = a monovalent cation such as methyl ammonium (MA), cesium (Cs), and formamidinium (FA) and X = a halogen such as I, Br, and Cl) is of great interest because a two dimensional (2D) layer structure with direct bandgap has narrower bandgap energy than a zero dimensional (0D) dimer structure with indirect bandgap. Here, we demonstrated 2D layer structured FACs2Sb2I6Cl3 MHP by dual-site (A and X site) mixing. Thanks to the lattice-symmetry change by I-Cl mixed halide, the shortest ionic radius of Cs, and the lower solution energy due to dual-site mixing, the FACs2Sb2I6Cl3 MHP had 2D layer structure and thereby the MHP solar cells exhibited improved short-circuit current density.

5.
ACS Appl Mater Interfaces ; 11(46): 43066-43074, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31657896

RESUMO

Highly efficient and thermally stable inorganic CsPbI2Br mesoscopic metal halide perovskite (MHP) solar cells with a poly-3-hexylthiophene (P3HT) hole transporting layer (HTL) are demonstrated by spin-washing of the P3HT HTL since the light harvesting efficiency is improved by minimizing the coabsorption of light by P3HT, and the open-circuit voltage is enhanced because of the increased valence band maximum position of the spin-washed P3HT HTL. The spin-washed CsPbI2Br MHP solar cell exhibited 1.24 V open-circuit voltage (Voc), 14.20 mA/cm2 short-circuit current density (Jsc), 81.52% fill factor (FF), and 14.35% power conversion efficiency (PCE). The unencapsulated spin-washed CsPbI2Br MHP solar cell went through 7.56% degradation after a 1000 h thermal stability test under 100 °C/25% relative humidity (RH) and simultaneous 1 sun light soaking conditions. In addition, the unencapsulated spin-washed CsPbI2Br MHP solar submodule with 25 cm2 of masked active area showed a 98% geometrical FF, 115.09 mA short-circuit current, 3.54 V Voc, 71.09% FF, and 11.58% PCE while exhibiting 8.80% of degradation during a thermal stability test at 100 °C/25% RH and 1 sun light soaking for 1000 h.

6.
J Toxicol Environ Health A ; 82(11): 678-695, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31328663

RESUMO

Disposable sanitary pads are a necessity for women's health, but safety concerns regarding the use of these products have created anxiety. The aim of this study was to conduct a risk assessment of 74 volatile organic compounds (VOCs), which were expected to be contained within sanitary pads. Of the 74 VOCs, 50 were found in sanitary pads retailed in Korea at concentrations ranging from 0.025 to 3548.09 µg/pad. In order to undertake a risk assessment of the VOCs, the toxicological database of these compounds in the United States Environmental Protection Agency (USEPA), Agency for Toxic Substances and Disease Registry (ATSDR), National Toxicology Program (NTP) and World Health Organization (WHO) was searched. Ethanol was found to exhibit the highest reference dose (RfD) while 1,2-dibromo-3-chloro-propane displayed the lowest RfD. Consequently, a worst-case exposure scenario was applied in this study. It was assumed that there was the use of 7.5 sanitary napkins/day for 7 days/month. In the case of panty liners or overnight sanitary napkins, the utilization of 90 panty liners/month or 21 overnight sanitary napkins/month was assumed, respectively. In addition, 43 kg, the body weight of 12 to 13-year-old young women, and 100% VOCs skin absorption were employed for risk assessment. The systemic exposure dose (SED) values were calculated ranging from 1.74 (1,1,2-trichloroethane) ng/kg/day to 144.4 (ethanol, absolute) µg/kg/day. Uncertainty factors (UFs) were applied ranging from 10 to 100,000 in accordance with the robustness of animal or human experiments. The margin of exposure (MOE) of 34 VOCs was more than 1 (acceptable MOE > 1). Applicable carcinogenic references reported that the cancer risk of five VOCs was below 10-6. Based on our findings, evidence indicates that the non-cancer and cancer risks associated with VOCs detected in sanitary pads currently used in South Korea do not pose an adverse health risk in women.


Assuntos
Poluentes Atmosféricos/análise , Qualidade de Produtos para o Consumidor , Exposição Ambiental/análise , Compostos Orgânicos Voláteis/toxicidade , Monitoramento Ambiental , Humanos , Medição de Risco , Fatores de Risco , Saúde da Mulher
7.
Chem Biol Interact ; 284: 41-47, 2018 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-29462589

RESUMO

Certain cosmetic colorants are irritant to skin or aggravate dermatitis. Thymic stromal lymphopoietin (TSLP) plays an important role in the initiation and progress of skin inflammation and atopic dermatitis by triggering Th2 immune responses. However, the effects of cosmetic colorants on TSLP production are unknown yet. Therefore, we investigated whether cosmetic colorants regulated TSLP production and dermatitis. Lithol Rubine B (LR-B, Pigment Red 57) and its calcium salt (LR-BCA), commonly used cosmetic colorants, potentiated phorbol-12-myristate-13-acetate-induced TSLP production in keratinocytes. In addition, the topical exposure to LR-B or LR-BCA on mouse ear upregulated a TSLP inducer (MC903)-induced TSLP production and Th2 cytokine expression. Dermatitis symptoms and serum IgE and histamine levels were also aggravated by LR-B or LR-BCA, implicating the role of increased TSLP expression in acute dermatitis. LR-B or LR-BCA induced IκBα degradation and NF-κB activation in keratinocytes, leading to TSLP expression. Collectively, our results demonstrate that LR-B and LR-BCA increase TSLP expression and Th2 immune responses, thereby aggravating acute dermatitis in the compromised skin. The results further suggest that certain cosmetic colorants such as LR-B may aggravate dermatitis under pro-inflammatory conditions by upregulating TSLP production.


Assuntos
Corantes/toxicidade , Citocinas/metabolismo , Dermatite Atópica/etiologia , Pele/efeitos dos fármacos , Animais , Compostos Azo/toxicidade , Benzenossulfonatos/toxicidade , Linhagem Celular , Citocinas/análise , Dermatite Atópica/metabolismo , Modelos Animais de Doenças , Orelha/patologia , Histamina/sangue , Imunoglobulina E/sangue , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ésteres de Forbol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células Th2/citologia , Células Th2/efeitos dos fármacos , Células Th2/metabolismo , Regulação para Cima/efeitos dos fármacos , Linfopoietina do Estroma do Timo
8.
J Phys Ther Sci ; 29(2): 235-237, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28265147

RESUMO

[Purpose] The aim of this study was to determine the effect of stair task training on gait abilities by conducting stair task training. In this training, step training is applied in various directions with hemiplegia patients. [Subjects and Methods] Thirty-six patients with stroke were selected on the basis of inclusion and exclusion criteria, and they were randomly divided into eighteen patients in the experimental group and eighteen patients in the control group via draw. [Results] In this study, the Dartfish program was used to measure gait capabilities. Experiment group showed a statistically significant improvement in the swing phase time of the affected lower extremity compared to control group. [Conclusion] It was found that the stair task training group had effective results in the swing phase time of the affected lower extremity compared with the group that applied weight support on the affected lower extremity and balance training.

9.
J Phys Ther Sci ; 28(4): 1166-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27190448

RESUMO

[Purpose] The aim of this study was to evaluate the overlap effect of the PNF following the application of Kinesio taping and the McConnell taping, and also the impact of the taping application method on the balance and walking speed of the patients with stroke. [Subjects and Methods] Thirty-six patients who were diagnosed with hemiplegia due to stroke were selected as subjects of this study. They were randomly and evenly divided into experiment group 1 (Kinesio taping group), experiment group 2 (McConnell taping group), and the control group; each group had 12 patients. [Results] The Berg balance scale (BBS) was used to evaluate balance, and the ability in this study. A 10 m walking test (10MWT) was performed to measure the walking speed. Experiment group 1 showed a statistically significant improvement in balance and walking speed compared to experiment group 2, and the control group in week 4 and week 8. [Conclusion] Application of Kinesio taping had a more beneficial effect on the balance and walking speed than joint-fixation taping of the patients with stroke.

10.
J Chromatogr Sci ; 53(7): 1100-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25523464

RESUMO

Chloroacetamide (CAA) is a preservative used in various cosmetic, personal care and household products. Due to the hazard potential for allergic reaction and reproductive toxicity, CAA is being considered a high priority for screening assessment and toxicological re-evaluation. This study describes the development of a highly specific and sensitive atmospheric pressure chemical ionization tandem mass spectrometry method for the determination of CAA in rat plasma and its application to a topical bioavailability study. Chromatographic separations were achieved on a C8 column using a highly aqueous mobile phase with a binary gradient elution. The assay was linear in the concentration range of 5-2,500 ng/mL (r ≥ 0.995) using a small sample volume (100 µL). Applicability of the assay was demonstrated in a bioavailability study in rats after i.v. injection (0.5 or 2 mg/kg) and topical application (7.02 mg/kg). Average elimination half-life and clearance ranged from 26.6 to 30.5 min and 53.9 to 57.3 mL/min/kg, respectively. Upon topical application, CAA was slowly but steadily absorbed for a prolonged time period (12 h). The topical bioavailability was 53.5 and 48.3% for emulsion and lotion, respectively. The developed assay may be useful to examine the relationship between exposure and toxic potential of CAA in risk assessment.


Assuntos
Acetamidas/farmacocinética , Cromatografia Líquida/métodos , Excipientes/farmacocinética , Espectrometria de Massas em Tandem/métodos , Acetamidas/administração & dosagem , Acetamidas/sangue , Administração Tópica , Animais , Disponibilidade Biológica , Excipientes/administração & dosagem , Excipientes/análise , Meia-Vida , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
11.
J Phys Ther Sci ; 26(11): 1831-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25435710

RESUMO

[Purpose] The aim of this study was to evaluate the changes in function and balance after Kinesio Taping application in stroke patients. [Subjects and Methods] Thirty subjects were randomly divided into an experimental group and control group. The experimental group was applied taping before therapeutic exercise, and the control group received only therapeutic exercise. Functional gait was measured using the straight line walking test, and dynamic balance ability was measured using the Berg Balance Scale. Walking velocity was measured with the 10 m walking test. [Results] There were statistically significant differences between the results of the straight line walking and 10 m walking tests in the pre-post analysis for the experimental group. There were a statistically significant difference in the Berg Balance Scale and 10 m walking test between the two groups. [Conclusion] Application of taping to the paralyzed parts of a stroke patient has a positive effect on improvement of typical asymmetric gait and walking speed.

12.
J Phys Ther Sci ; 25(9): 1119-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24259927

RESUMO

[Purpose] The purpose of this study was to compare the effects of taping on the articular angle of the knee joint and on the functioning of patients with hemiplegia resulting from stroke. [Subjects] The subjects of this study were 30 patients who were diagnosed with hemiplegia due to stroke. The subjects were randomly assigned to either an experimental group which received proprioceptive neuromuscular facilitation combination patterns and kinesio taping were applied, or a control group which received neurodevelopmental treatment. [Methods] Joint angle was measured at the hip and the ankle for both the paretic and non-paretic sides using a goniometer. Dynamic balance ability was assessed using the Berg Balance Scale. Gait velocity was measured as the 10-m walking time using a stopwatch. [Results] Comparative analysis of the experimental group's pre-test and post-test results showed statistically significant differences in the BBS and 10-m walking test. There were significant differences between the groups in ankle dorsiflexion, BBS, and 10-m walking times. [Conclusion] We judge the application of taping on the knee joint prior to rehabilitation treatment for patients in accordance with nervous system damage positively influences their functional improvement.

13.
J Phys Ther Sci ; 25(11): 1359-62, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24396188

RESUMO

[Purpose] This study examined the effects of scapular stabilization exercises immediately after surgery on pain and function in patients diagnosed with shoulder impingement syndrome. [Subjects] The subjects were assigned by random sampling to an experimental group (n=15) to which stabilization exercise was applied and a control group (n=15) to which ordinary physical treatment was applied. [Methods] To evaluate the degree of pain, a 100 mm visual analogue scale (VAS) was used. The Constant-Murley Scale (CMS) was used to evaluate the functions of the shoulder joints. To determine the range of motion, a goniometer was used to measure range of shoulder motion. The simple shoulder test (SST) was used to determine the condition of the shoulder joints of the subjects. [Results] There were significant differences in all the items of the experimental group. The results of comparison of the therapeutic effect in the experimental and control groups revealed significant differences in active abduction, passive abduction, VAS, SST, and the CMS, except for pain. [Conclusion] The results suggest that shoulder stabilization exercise positively affects pain alleviation and functional recovery in shoulder impingement patients.

14.
Opt Express ; 19(7): 6243-52, 2011 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21451649

RESUMO

We propose and experimentally demonstrate a hybrid WDM/OCDMA ring with a dynamic add/drop function based on Fourier code for local area networks. Dynamic function is implemented by mechanically tuning the Fourier encoder/decoder for optical code division multiple access (OCDMA) encoding/decoding. Wavelength division multiplexing (WDM) is utilized for node assignment and 4-chip Fourier code recovers the matched signal from the codes. For an optical source well adapted to WDM channels and its short optical pulse generation, reflective semiconductor optical amplifiers (RSOAs) are used with a fiber Bragg grating (FBG) and gain-switched. To demonstrate we experimentally investigated a two-node hybrid WDM/OCDMA ring with a 4-chip Fourier encoder/decoder fabricated by cascading four FBGs with the bit error rate (BER) of <10(-9) for the node span of 10.64 km at 1.25 Gb/s.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Compressão de Dados/métodos , Tecnologia de Fibra Óptica/instrumentação , Dispositivos Ópticos , Processamento de Sinais Assistido por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Análise de Fourier
15.
Kisaengchunghak Chapchi ; 8(2): 58-62, 1970 Aug.
Artigo em Coreano | MEDLINE | ID: mdl-12913515

RESUMO

Total 9 cases of extraintestinal amoebiasis, amebic liver abscess and amebic lung abscess, were treated with metronidazole. The diagnosis and progress check were done by (1) stool examination, (2) size and pain of liver, (3) hematological examination, (4) urinanalysis, (5) X-ray or liver scanning (6) examination of aspirated pus from liver and (7) immobilization test of E. histolytica. Results are summarized as follows: 1. Amebic hepatitis: Metronidazole was given to 3 cases with daily dose of 0.9-1.2 gm for 3-7 days. Clinical symptoms were completely restored by the treatment. 2. Amebic lung abscess: One case was treated with metronidazole for 3 days with the daily dose 1.2 gm. X-ray findings showed remarkable improvement by the treatment. An additional administration of the drug for 6 days resulted complete resolution of the pneumonic changes. 3. Amebic liver abscess: Four cases were treated with metronidazole. The daily doses were 0.4-2.4 gm and continued for 2-10 days. Aspiration of the abscess for 1-10 times or continuous drainage of pus were performed during the course supplementarily. All cases were recovered to normal by the combining treatment. No remarkable side effect was noticed by the drug administration, and no relapse was experienced up to date.

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