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1.
Artigo em Inglês | MEDLINE | ID: mdl-38574248

RESUMO

Background and Aims: Cannabigerol (CBG) is a nonintoxicating cannabinoid synthesized in the Cannabis sativa plant that is incorporated into dietary supplements. This study investigated the influence of dietary fat and an emulsified delivery vehicle on CBG pharmacokinetics (PKs) after oral ingestion by adults. Materials and Methods: Consented participants were enrolled in a double-crossover pilot study and were blinded to the delivery vehicle type (isolate or emulsification) and isocaloric meal condition (low-fat=<5 g fat/meal or high-fat [HF]=>30 g fat/meal). The concentration of CBG in human plasma was measured after a single 25 mg dose of CBG using liquid chromatography-tandem mass spectrometry (LC-MS/MS). PK parameters were calculated using noncompartmental analysis. Results: The PKs of the two delivery systems (emulsified vs. non-emulsified) were significantly impacted by the HF meal condition. Participants in the HF meal group exhibited significantly higher area under the plasma concentration time curve from time 0 to last quantifiable value, maximum concentration, and terminal half-life. Participants in the HF meal group also had a significantly lower terminal elimination rate constant and time to maximum concentration (Tmax), in addition to decreased Tmax variation. The threshold for bioequivalence between conditions was not met. An exploratory aim correlated anthropometric measures and previous day's dietary intake on PK parameters which yielded inconsistent results across dietary fat conditions. Conclusions: In aggregate, dietary fat had a greater effect on CBG PKs than the emulsified delivery vehicle. This supports accounting for dietary intake in development of therapeutics and administration guidelines for orally delivered CBG.

2.
PLoS One ; 18(9): e0291052, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37683016

RESUMO

BACKGROUND: Psychological status affects dietary intake, and recognizing genetic information can lead to behavior changes by influencing psychological factors such as anxiety or depression. OBJECTIVES: In this study, we examined the effects of disclosing genetic information on anxiety or depression levels and the association between these psychological factors and dietary intake. METHODS: A total of 100 healthy adults were randomly assigned to an intervention group (n = 65) informed about their genetic test results regarding body mass index and lipid profiles (triglyceride and cholesterol concentrations) and a not-informed control group (CON, n = 35). Based on polygenic risk scores, participants in the intervention group were subclassified into an intervention-low risk (ILR, n = 32) and an intervention-high risk (IHR, n = 33) group. Nutrient and food intakes were assessed via a 3-day dietary record at baseline and at 3 and 6 months. Depression and anxiety levels were measured using PHQ-9 and GAD-7 questionnaires, and the relative levels of blood metabolites were measure using GC-MS/MS analysis. RESULTS: Noticeable changes in dietary intake as well as psychological factors were observed in male subjects, with those perceiving their genetic risks as low (ILR) showing a significant increase in protein intake at 3 months compared to baseline (ILR: 3.9 ± 1.4, p<0.05). Meat intake also increased significantly in males in the ILR group at 3 months, but not in the IHR and CON groups (ILR: 49.4 ± 30.8, IHR: -52.2 ± 25.4, CON: -5.3 ± 30.3 g/d). ILR group showed a significant decrease in anxiety levels at 3 months, and their anxiety scores showed a negative association with meat intake (standardized ß = -0.321, p<0.05). The meat intake at 3 months was associated with the relative levels of arginine and ornithine (standardized ß = 0.452, p<0.05 and standardized ß = 0.474, p<0.05, respectively). CONCLUSIONS: Taken together, anxiety levels were decreased in male subjects who perceived their genetic risk to be low, and the decrease in anxiety levels was associated with an increase in meat intake. This suggests that recognizing genetic information may affect psychological factors and dietary intake.


Assuntos
Depressão , Espectrometria de Massas em Tandem , Adulto , Masculino , Humanos , Triglicerídeos , Índice de Massa Corporal , Depressão/genética , Ansiedade/genética , Fatores de Risco , Lipoproteínas , Carne
3.
Pest Manag Sci ; 79(2): 678-687, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36229424

RESUMO

BACKGROUND: Exposure of agricultural workers in rice paddies to the insecticide chlorantraniliprole and its subsequent potential health risks were investigated during two scenarios (mixing/loading and hand-held spraying). The exposure factors, such as the outer dosimeter, inner dosimeter, gauze, and nitrile gloves, were calculated using whole-body dosimetry to measure dermal exposure. The inhalation exposure was determined using a fiberglass filter which is set with an Institute of Occupational Medicine (IOM) sampler. A recovery test was performed to evaluate the accuracy of the analytical method. RESULTS: The exposure amounts of various matrices were calculated from extraction volume and concentration of the target compound. The dermal exposure to chlorantraniliprole was 0.6 mg [0.001% of the total active ingredient (a.i.)] for mixing and loading, and 28.6 mg (0.066% of the total a.i.) for application. The inhalation exposure to chlorantraniliprole was 7.2 µg (1.3%, 1.2 × 10-5 % of the total applied a.i.) for mixing and loading, and 1.9 µg (0.006%, 4.4 × 10-6 % of the total applied a.i.) for application. The most exposed part of the body was the hand (90.4%) during mixing and loading, whereas the primary sites during application were the thighs (32.8%) and shins (22.6%). For mixing and loading, the amount of actual dermal exposure was 5.5 µg day-1 and that of actual inhalation exposure was 21.9 µg day-1 . By contrast, in the application, the amounts of actual dermal and actual inhalation exposures were 34 178.7 and 5.9 µg day-1 , respectively. CONCLUSIONS: The risk assessment results demonstrated that the risk of chlorantraniliprole exposure in rice paddies was low during application than during mixing and loading. © 2022 Society of Chemical Industry.


Assuntos
Inseticidas , Exposição Ocupacional , Oryza , Humanos , Inseticidas/análise , Exposição Ocupacional/análise , Fazendeiros , Medição de Risco , Exposição por Inalação/análise
4.
Ecotoxicol Environ Saf ; 243: 113988, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029578

RESUMO

Dermal & inhalation exposure was examined and according to these results, risk assessment of agricultural workers to thiamethoxam was performed during pesticide mixing/loading and hand-held sprayer application (11 replicates, each of about 1000 L of spray suspension) in vineyards. For the whole body dosimetry (WBD), clothing (Outer and inner), gauze, and nitrile gloves were analyzed to determine dermal exposure using whole-body dosimetry exposure protocol. The inhalation exposure was measured using a glass fiber filter with an IOM sampler. Analytical method validation of exposure matrices was evaluated including the field recovery and breakthrough test. The dermal exposure amount during mixing/loading was 0.163 mg (0.0004% of the total mixed/loaded active ingredient [a.i.]), whereas there was no inhalation exposure. The gloves (0.154 mg, 94.5%) were the most exposed body parts followed by the chest and stomach (0.009 mg, 5.5%). During application, the dermal and inhalation exposure amounts were 32.3 mg (0.07% of the total applied a.i.) and 10.8 µg (2.4 × 10-6% of the total applied a.i), respectively. The shin (35.1%) had the highest exposure to pesticides, followed by the chest & stomach (15.6%) and pelvis (12.6%). In case of mixing/loading, the amounts of actual dermal exposure (ADE) and actual inhalation exposure (AIE) were 0.0 and 0.0 µg/day, while those of ADE and AIE were 4707.6 and 15.8 µg/day for application. In risk assessment of the two different scenarios, the risk index was much lower than 1 (mixing/loading:0.000, application:0.014), indicating that vineyard workers are at low risk of thiamethoxam exposure. To determine the validity of the risk assessment using WBD method, the urinary metabolite was analyzed. Comparison of biomonitoring data and WBD exposure data show a reliable correlation (r = 0.885, p = 0.0003), suggesting that these are suitable methods to estimate exposure.


Assuntos
Exposição Ocupacional , Praguicidas , Fazendeiros , Fazendas , Humanos , Exposição Ocupacional/análise , Medição de Risco , Tiametoxam
5.
Food Chem ; 374: 131626, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34838406

RESUMO

A rapid screening method for the quantitative analysis of pesticide multiresidues using a high-resolution accurate mass (HRAM) quadrupole time-of-flight (Q-TOF) with a dopant-assisted gas chromatography-atmospheric pressure chemical ionization (GC-APCI) technique were developed. For convenient and constant supply of APCI dopant, a large-volume dopant bottle with a bypass valve was newly designed, and the developed method was tested with 415 pesticide mixtures for representative produce (orange, chili pepper, and brown rice). Methanol-enriched nitrogen gas was used to produce protonated molecular [M + H]+ ions, and fragment ions were produced by broad-band collision-induced dissociation mode. Twenty representative pesticides were selected and validated for analytical performance. The methanol dopant-assisted GC-APCI-Q-TOF technique is very promising for target and non-target screening and sensitive quantification for hundreds of pesticides in a single run.


Assuntos
Capsicum , Citrus sinensis , Oryza , Praguicidas , Pressão Atmosférica , Cromatografia Gasosa-Espectrometria de Massas , Praguicidas/análise
6.
Chemosphere ; 277: 130215, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33774252

RESUMO

Multiresidual pesticide analysis in hair can provide useful perspectives on the relationship between pesticides and human health. To establish a rapid and simultaneous analytical method using LC-MS/MS and GC-MS/MS, optimization of hair pulverization, extraction solvent and purification with dispersive SPE was performed for 300 pesticides. Hair pulverization was standardized with a ball mill, at 30 Hz for 20 min (10 min twice), using 3-mm diameter beads. For extraction, 0.1% formic acid in acetonitrile was selected, and PSA d-SPE was chosen for clean-up among three different types of solid phase extraction. The limits of quantitation (LOQs) in this method were between 2.5 and 7.5 pg mg-1. In recovery test, fifty milligrams of hair powder were extracted with 0.1% formic acid in acetonitrile, and incubated for three h at 40 ℃. The crude extract was treated using PSA-dSPE, dried under nitrogen gas, and reconstructed with acetonitrile. An aliquot was analyzed with LC- and GC-MS/MS. Recovery ranges were 22.7-131.1%, in LC-MS/MS analysis, and 81.1-151.8% in GC-MS/MS analysis. The validated analysis systems were applied to biomonitoring of ten agricultural workers, and residues of 28 target pesticides were detected in their hair.


Assuntos
Resíduos de Praguicidas , Monitoramento Biológico , Cromatografia Líquida , Fazendeiros , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Resíduos de Praguicidas/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem
7.
J Hazard Mater ; 389: 122056, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32000124

RESUMO

Endosulfan sulfate is a major oxidative metabolite of the chlorinated insecticide endosulfan. In this study, a targeted metabolomics approach was used to investigate the toxic mechanisms of endosulfan sulfate in adult zebrafish using the multiple reaction monitoring mode of a GC-MS/MS. The LC50 of endosulfan sulfate in adult zebrafish was determined and then zebrafish were exposed to endosulfan sulfate at one-tenth the LC50 (0.1LC50) or the LC50 for 24 and 48 h. After exposure, the fish were extracted, derivatized and analyzed by GC-MS/MS for 379 metabolites to identify 170 metabolites. Three experimental groups (control, 0.1LC50 and LC50) were clearly separated in PLS-DA score plots. Based on the VIP, ANOVA, and fold change results, 40 metabolites were selected as biomarkers. Metabolic pathways associated with those metabolites were identified using MetaboAnalyst 4.0 as follows: aminoacyl-tRNA biosynthesis, valine/leucine/isoleucine biosynthesis, citrate cycle, glycerolipid metabolism, and arginine/proline metabolism. Gene expression studies confirmed the activation of citrate cycle and glycerolipids metabolism. MDA levels of the exposed group significantly increased in oxidative toxicity assay tests. Such significant perturbations of important metabolites within key biochemical pathways must result in biologically hazardous effects in zebrafish.


Assuntos
Endossulfano/análogos & derivados , Metaboloma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Catalase/genética , Endossulfano/toxicidade , Cromatografia Gasosa-Espectrometria de Massas/estatística & dados numéricos , Expressão Gênica/efeitos dos fármacos , Malondialdeído/metabolismo , Metabolômica/métodos , Análise Multivariada , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Espectrometria de Massas em Tandem/estatística & dados numéricos , Peixe-Zebra
8.
Sci Rep ; 9(1): 11648, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406178

RESUMO

The dissipation patterns of cyantraniliprole and its metabolite IN-J9Z38 were investigated using proso millet (Panicum miliaceum) under open-field conditions to establish a pre-harvest interval. A simple and sensitive analytical method was developed for analyzing residues using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) for multiple reaction monitoring of target compounds. The analytical method was validated in terms of the instrumental limit of quantitation, method limit of quantitation, linearity, accuracy, and precision. The method was successfully applied to the analysis of cyantraniliprole and IN-J9Z38 residues in the field samples of four plots, which were treated twice with an oil dispersion formulation, according to the date of pesticide treatment before harvest. In the case of cyantraniliprole in grain and straw, there was a 91.1 and 89.1% decrease, respectively, from the initial residues (14-7 days) to the final plot (40-30 days before harvest). However, IN-J9Z38 gradually increased over time, indicating that cyantraniliprole transformed into IN-J9Z38 during cultivation. The biological half-lives of total cyantraniliprole were 11.3 and 9.4 days for grain and straw, respectively. The results obtained in this study will inform regulation and management of pesticide use for the minor crop proso millet.


Assuntos
Inseticidas/análise , Panicum/química , Resíduos de Praguicidas/análise , Pirazóis/análise , ortoaminobenzoatos/análise , Cromatografia Líquida de Alta Pressão/métodos , Produção Agrícola/métodos , Produção Agrícola/normas , Grão Comestível/química , Grão Comestível/normas , Meia-Vida , Inseticidas/metabolismo , Resíduos de Praguicidas/metabolismo , Caules de Planta/química , Pirazóis/metabolismo , Espectrometria de Massas em Tandem/métodos , ortoaminobenzoatos/metabolismo
9.
Molecules ; 24(7)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987340

RESUMO

Multiresidual pesticide determination in a biological sample is essential for an immediate decision and response related to various pesticide intoxications. A rapid and simultaneous analytical method for 260 pesticides in human urine was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). High speed positive/negative switching electrospray ionization (ESI) mode was used, and scheduled multiple reaction monitoring (MRM) was optimized. Three versions of scaled-down QuEChERS procedures were evaluated, and the procedure using non-buffer reagents (magnesium sulfate and sodium chloride) and excluding cleanup steps was selected for optimum pesticide extraction. The limit of quantitation (LOQ) in this methodology was 10 ng/mL for each target pesticide, and correlation coefficient (r²) values of calibration curves were ≥0.988 (linearity range; 10-250 ng/mL). In accuracy and precision tests, the relative error ranges were -18.4% to 19.5%, with relative standard deviation (RSD) 2.1%-19.9% at an LOQ level (10 ng/mL), and -14.7% to 14.9% (RSD; 0.6%-14.9%) at higher concentrations (50, 150, and 250 ng/mL). Recovery range was 54.2%-113.9% (RSD; 0.3%-20.0%), and the soft matrix effect (range; -20% to 20%) was observed in 75.4% of target pesticides. The established bioanalytical methods are sufficient for application to biomonitoring in agricultural exposures and applicable in the forensic and clinic.


Assuntos
Cromatografia Líquida , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/urina , Espectrometria de Massas em Tandem , Urinálise , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Urinálise/métodos , Urinálise/normas
10.
Bone ; 114: 150-160, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29775761

RESUMO

Irisin, a recently identified hormone secreted by skeletal muscle in response to exercise, exhibits anabolic effects on the skeleton primarily through the stimulation of bone formation. However, the mechanism underlying the irisin-stimulated anabolic response remains largely unknown. To uncover the underlying mechanism, we biosynthesized recombinant irisin (r-irisin) using an Escherichia coli expression system and used it to treat several osteoblast cell types. Our synthesized r-irisin could promote proliferation and differentiation of osteoblasts as evidenced by enhanced expression of osteoblast-specific transcriptional factors, including Runt-related transcription factor-2 (Runx2), Oster (Osx), as well as early osteoblastic differentiation markers such as alkaline phosphatase (Alp) and collagen type I alpha 1 (Col1a1). Furthermore, we showed that the promotion of r-irisin on the proliferation and differentiation of osteoblast lineage cells are preferentially through aerobic glycolysis, as indicated by the enhanced abundance of representative enzymes such as lactate dehydrogenase A (LDHA) and pyruvate dehydrogenase kinase 1 (PDK1), together with increased lactate levels. Suppression of r-irisin-mediated aerobic glycolysis with Dichloroacetate blunted its anabolic effects. The favorite of the aerobic glycolysis after r-irisin treatment was then confirmed in primary calvarial cells by metabolic analysis using gas chromatography-mass spectrometry. Thus, our results suggest that the anabolic actions of r-irisin on the regulation of osteoblast lineage cells are preferentially through aerobic glycolysis, which may help to develop new irisin-based bone anabolic agents.


Assuntos
Anabolizantes/farmacologia , Fibronectinas/biossíntese , Fibronectinas/farmacologia , Glicólise/fisiologia , Osteoblastos/metabolismo , Osteogênese/fisiologia , Células 3T3-L1 , Anabolizantes/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Cadeia alfa 1 do Colágeno Tipo I , Glicólise/efeitos dos fármacos , Humanos , Camundongos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos
11.
Chemosphere ; 207: 519-526, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29843028

RESUMO

In this study, we developed a multiresidue method for the analysis of 310 pesticides in representative agricultural produce (brown rice, orange, and spinach) using ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) combined with a modified QuEChERS procedure. The optimal mobile phase composition (Methanol containing 5 mM ammonium formate and 0.1% formic acid) produced high sensitivity and reliable results. Also, the relationship between injection volume and repeatability of peak area was investigated. Most of the target pesticides had a limit of quantitation under 10 ng g-1, and correlation coefficients (r2) > 0.99 in matrix-matched standards within the range of 1-100 ng g-1. To validate the optimized method, recovery tests were performed with each of the crops at 10 and 50 ng g-1 spiking levels (n = 5). Satisfactory recoveries were achieved showing that 86.8-88.7% (at 10 ng g-1) and 91.9-96.1% (at 50 ng g-1) of the pesticides met the validation criteria (recoveries in the range of 70-120% and relative standard deviation ≤ 20%). Fifteen compounds were found to show a loss of recovery due to adsorption by primary and secondary amine or graphite carbon black. In the case of brown rice, 86.1% of pesticides showed an insignificant matrix effect (<±20%), while 35.2% and 41.6% of pesticides in orange and spinach were in that range, respectively. Sixteen apple samples from local markets were analyzed to evaluate the applicability of the optimized method. Nineteen pesticides were detected, of which the concentrations were lower than the maximum residue limit.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citrus sinensis/metabolismo , Oryza/metabolismo , Resíduos de Praguicidas/análise , Spinacia oleracea/metabolismo , Espectrometria de Massas em Tandem/métodos
12.
Ecotoxicol Environ Saf ; 155: 94-100, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29510314

RESUMO

This study examined dermal and inhalation exposure of agricultural operators to kresoxim-methyl during pesticide mixing/loading and speed sprayer application (10 replicates, each of 3000 L of spray suspension) in an apple orchard and performed risk assessment. For the whole body dosimetry (WBD) exposure protocol, outer clothing, inner clothing, gauze, and nitrile gloves were examined to measure dermal exposure. In contrast, an IOM (institute of occupational medicine) sampler with a glass fiber filter was used to measure inhalation exposure. Analytical method accuracy in the exposure matrices was evaluated by a field recovery study. The dermal and inhalation exposure amounts for mixing/loading were 9.7 mg [0.002% of the total mixed/loaded active ingredient (a.i.)] and 1.2 µg (1.7 × 10-6% of the total mixed/loaded a.i.), respectively. The body parts more exposed were the forearms (35.5%), chest & stomach (30.2%), and hands (17.9%). During application, the dermal and inhalation exposure amounts were 66.5 mg (0.009% of the total applied a.i) and 34.8 µg (4.6 × 10-5% of the total applied a.i.), respectively. The shins (18.5%) and chest & stomach (16.0%) were exposed to higher proportion of pesticide, followed by the thighs (15.8%) and back (14.7%). Comparing the exposure pattern as assessed by the WBD method in the present study with the patch method as in our previous study, the ADE (actual dermal exposure) as measured by the WBD method was 25 times less than that measured by the patch method. The daily exposure amounts of ADE and AIE (actual inhalation exposure) for mixing/loading were 711.8 µg/day and 4.3 µg/day, respectively, whereas the amounts of ADE and AIE for application were 1825.8 µg/day and 116.1 µg/day. In risk assessment of the mixing/loading and application scenarios, the AOEL (acceptable operator exposure level) of kresoxim-methyl was used as the reference dose to show that the RI (risk index) was much lower than 1, indicating that agricultural operators are at low risk of exposure to kresoxim-methyl.


Assuntos
Poluentes Ocupacionais do Ar/análise , Fungicidas Industriais/análise , Exposição por Inalação/análise , Exposição Ocupacional/análise , Absorção Cutânea , Estrobilurinas/análise , Adulto , Fazendeiros , Humanos , Masculino , Malus , Medição de Risco
13.
J Agric Food Chem ; 66(13): 3550-3560, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29536730

RESUMO

A screening method for simultaneous analysis of 379 pesticides in human serum was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Electrospray ionization with positive/negative switching mode of LC-MS/MS was adopted, and scheduled multiple reaction monitoring for each target compound was established. The limit of quantitation was 10 ng/mL for 94.5% of the total pesticides, and the correlation coefficients of calibration were ≥0.990 for 93.9% of the pesticides. For the sample preparation, scaled-down QuEChERS were used. Serum (100 µL) was extracted with acetonitrile (400 µL), partitioned with magnesium sulfate (40 mg) and sodium chloride (10 mg), and the upper layer was used for analysis without further cleanup steps. For the accuracy and precision tests, most of the pesticides showed excellent results in intra- and interday conditions. In the recovery tests at 10, 50, and 250 ng/mL, 85.8-91.8% of all target compounds satisfied the recovery range of 70-120% (relative standard deviation ≤20%).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Praguicidas/sangue , Soro/química , Espectrometria de Massas em Tandem/métodos , Humanos , Praguicidas/química , Praguicidas/isolamento & purificação , Extração em Fase Sólida
14.
J Audiol Otol ; 21(3): 133-139, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28942627

RESUMO

BACKGROUND AND OBJECTIVES: Listeners with sensorineural hearing loss want to compensate for their narrow dynamic range from appropriate compression functions of hearing aids. The present study aimed to determine which compression threshold and release time of nonlinear hearing aids might affect speech recognition and speech quality judgments. SUBJECTS AND METHODS: Ten elderly listeners with symmetrical moderate-to-severe sensorineural hearing loss participated in the study. To compare two compression threshold (31 dB SPL vs. 61 dB SPL) and two release time (50 ms vs. 500 ms) conditions, subjects' speech recognition was measured using the Korean version of the Hearing in Noise Test in both quiet and noisy situations. All subjects were also asked to rate the degree of speech quality in terms of loudness, sharpness, clarity, and background noise immediately after completing the speech recognition test. RESULTS: Although no significant difference emerged in speech recognition thresholds between the two compression thresholds in the quiet situation, the compression threshold of 31 dB SPL showed a lower (or better) signal-to-noise ratio of speech recognition compared to that of 61 dB SPL. The release times of 50 and 500 ms did not statistically differ in both quiet and noisy situations. Subjective categories were found to be louder and clearer in the 50 ms release time for quiet and noisy, respectively. CONCLUSIONS: We expect that these patterns of current results will apply for better-fitting protocol of elderly Korean hearing aid users.

15.
J Audiol Otol ; 21(2): 120-123, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28704901

RESUMO

Evidence based practice has become an important aspect in many healthcare provisions to improve patient outcomes. Investigating the gaps between knowing and doing in audiology practice will provide future directions for successful service delivery. The purpose of this study was to explore "know-do" gaps related to professional awareness and attitude in hearing aid fitting management (HAFM) by analyzing data of a questionnaire. It consisted of 22 questions focusing on 11 HAFM components. Each component had two sub-questions involving levels of the importance and practice for HAFM. Respondents answered each question based on subjective judgments for their own hearing aid fitting services with a Visual Analogue Scale. A total of 51 responses from hearing care professionals were collected and the scores for knowing and doing were compared. The results showed overall high scores in doing and knowing responses; however, there were significant "know-do" gaps demonstrating higher knowing scores than doing scores across all HAFM components. The largest "know-do" gaps were observed in three components mostly implemented during follow-up sessions which indicate the need to improve their corresponding services and practical guidelines emphasizing the follow-up services.

16.
J Agric Food Chem ; 65(16): 3387-3395, 2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28345909

RESUMO

A multiresidue method for the simultaneous and rapid analysis of 360 pesticides in representative agricultural produce (brown rice, orange, spinach, and potato) was developed using a modified QuEChERS procedure combined with gas chromatography-tandem mass spectrometry (GC-MS/MS). Selected reaction monitoring transition parameters (e.g., collision energy, precursor and product ions) in MS/MS were optimized to achieve the best selectivity and sensitivity for a wide range of GC-amenable pesticides. A short (20 m) microbore (0.18 mm i.d.) column resulted in better signal-to-noise ratio with reduced analysis time than a conventional narrowbore column (30 m × 0.25 mm i.d.). The priming injection dramatically increased peak areas by masking effect on a new GC liner. The limit of quantitation was <0.01 mg/kg, and the correlation coefficients (r2) of matrix-matched standards were >0.99 within the range of 0.0025-0.1 mg/kg. Acetonitrile with 0.1% formic acid without additional buffer salts was used for pesticide extraction, whereas only primary-secondary amine (PSA) was used for dispersive solid phase extraction (dSPE) cleanup, to achieve good recoveries for most of the target analytes. The recoveries ranged from 70 to 120% with relative standard deviations of ≤20% at 0.01 and 0.05 mg/kg spiking levels (n = 6) in all samples, indicating acceptable accuracy and precision of the method. Seventeen real samples from local markets were analyzed by using the optimized method, and 14 pesticides in 11 incurred samples were found at below the maximum residue limits.


Assuntos
Citrus sinensis/química , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Oryza/química , Resíduos de Praguicidas/química , Solanum tuberosum/química , Spinacia oleracea/química , Limite de Detecção
17.
J Audiol Otol ; 20(2): 80-4, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27626080

RESUMO

BACKGROUND AND OBJECTIVES: The band-importance function (BIF) refers to a value characterizing the relative importance of different frequencies to speech intelligibility. The purpose of this study was to derive the BIF for the Korean standard sentence lists for adults (KS-SL-A). SUBJECTS AND METHODS: In this study, sentences from the KS-SL-A were used as the speech material. Twenty-six normal-hearing Korean listeners participated and intelligibility scores in 8 filters with 3 signal-to-noise ratio conditions were obtained. Based on the intelligibility score percentages, the BIF for the KS-SL-A was derived by using an established protocol. RESULTS: Band-importance weights varied across frequency bands. The most important frequency region was around 316 Hz (20.0%), and the importance of the frequency bands below the center frequency (CF) of 1,778 Hz was 59.6%. Therefore, low frequencies below the CF of 1,778 Hz were more important than high frequencies above the CF of 1,778 Hz. CONCLUSIONS: The BIF for KS-SL-A could be applied towards developing a hearing aid fitting formulae for Korean listeners.

18.
J Audiol Otol ; 20(2): 109-13, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27626085

RESUMO

The present report provides an overview of terminology studies in audiology including topics and study characteristics, as well as categorizing the main issues. The goals are to improve the understanding of the current issues for terminology in audiology and to provide some basic information that will be useful to develop an international standard. Search procedures were completed over two phases. Phase 1 included a systematic electronic searches using MEDLINE (PubMed), Excerpta Medica Database, Cumulative Index to Nursing and Allied Health Literature, and International Organization for Standardization with keywords related to terminology of audiology. The studies were initially identified according to the titles of 2921 publications following careful abstract examination. Of these, whole texts of 16 publications were retrieved. Five papers met the inclusion criteria were further investigated. In phase 2, a manual search was conducted to collect additional publications with keywords related to terminology project in audiology. A total of 16 papers were found. The essential terminology issues classified included 'appropriateness,' 'classification/framework,' 'inconsistency of terminology,' 'multilingual and international aspects,' and 'service quality/delivery including communication and accessibility.' This was indicative of the paucity of terminology research in audiology, despite recurring terminology issues. Establishment of standardized terminology in audiology may minimize current challenging terminology issues by improving appropriateness and consistency of terminology as well as communication among relevant stakeholders at national and international levels.

19.
J Audiol Otol ; 20(1): 1-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27144226

RESUMO

Hearing aids are one of the most widely used treatment options for the hearing impaired and optimal outcomes of hearing aids are supported by comprehensive hearing aid fitting protocols. Currently, the term 'hearing aid fitting' is prevalently used among service and industry sectors with its comprehensive procedures not systematically explicated. In addition, a variety of non-normalized guidelines for hearing aid fitting has led to non-uniform care, outcome variability, and dissatisfaction of the use of hearing aids. The main purpose of the present study is to suggest a general framework of standardized practice for hearing aid fitting management including its pre- and post-fitting stages. The management framework centers on its fitting process with its prior steps of assessment as well as its posterior steps of follow-up, thereby eliminating diverging interpretations and non-uniform practices. Outcomes of this study are also expected to improve potential benefits such as quality of hearing aid fitting, user satisfaction, and cost effectiveness across relevant stakeholders.

20.
J Audiol Otol ; 19(2): 68-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26413571

RESUMO

BACKGROUND AND OBJECTIVES: The purpose was to establish the test-retest reliability of word recognition score (WRS) using Korean standard monosyllabic word lists for adults (KS-MWL-A) recently developed based on the international standard for speech audiometry (ISO 8253-3:2012). SUBJECTS AND METHODS: Subjects consisted of 159 adults aged to 18 to 25 years with normal hearing sensitivity. WRSs were obtained in 2 dB steps from the level of speech recognition thresholds to the level of 86% correct responses or greater. After one or two weeks, retest was performed. Correlation, confidence interval (CI) and prediction interval (PI) were calculated for the reliability. RESULTS: Correlation coefficients were 0.88 for 50 test words, 0.76 for 25 and 0.61 for 10 words. Results also showed that 95% CIs and PIs were narrower for 25 and 50 test words than those for 10 test words. CONCLUSIONS: Korean WRS using the KS-MWL-A has high reliability for 25 and 50 test words, but relatively low for 10 words. It suggested that 95% CIs for each test words would be criteria for significant differences in WRS for groups and 95% PIs at each score of WRS could be utilized for a considerable difference for each individual at retest.

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