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1.
Environ Sci Pollut Res Int ; 30(45): 100552-100561, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37635162

RESUMEN

Bisphenol A (BPA) and parabens (PBs) are chemicals that are extensively used in personal care products (PCPs). In early childhood development, hearing is critical to speech and language development, communication, and learning. In vitro and in vivo, BPA/PBs exhibited neurotoxicity through elevated levels of oxidative stress. BPA also has the potential to be an ototoxicant. Therefore, this study aimed to determine the association of exposure to BPA/PBs with sensorineural hearing loss in children. A cross-sectional study based on hearing tests was conducted. This study enrolled 320 children aged 6-12 years from elementary school. Urinary BPA and PB concentrations were analyzed by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Logistic regression models were employed to determine the association of BPA/PB exposure with sensorineural hearing loss. Children with sensorineural hearing loss had higher BPA concentrations than normal-hearing children (0.22 ng/ml vs. 0.10 ng/ml, p = 0.05). After adjustment for covariates, the risk of hearing loss at middle frequencies reached 1.83-fold (95% CI: 1.12-2.99) when BPA concentrations increased by 1 log10. The risk of slight hearing loss reached 2.24-fold (95% CI: 1.05-4.78) when children had a tenfold increase in ethyl paraben (EP) concentration. This study clarifies the role of exposure to BPA/PBs in hearing loss in children. Future research needs to be expanded to include cohort designs and nationwide studies to identify causality.


Asunto(s)
Pérdida Auditiva Sensorineural , Parabenos , Humanos , Niño , Preescolar , Cromatografía Liquida , Parabenos/análisis , Estudios Transversales , Espectrometría de Masas en Tándem , Compuestos de Bencidrilo/análisis , Pérdida Auditiva Sensorineural/inducido químicamente
2.
Physiol Behav ; 255: 113922, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35905807

RESUMEN

The auditory brainstem response to complex sounds (cABR) could be evoked using speech sounds such as the 40 ms synthetic consonant-vowel syllable /da/ (CV-da) that was commonly used in basic and clinical research. cABR consists of responses to formant energy as well as the energy of fundamental frequency. The co-existence of the two energy makes cABR a mixed response. We introduced a new stimulus of click-sawtooths (CSW) with similar time-lock patterns but without formant or harmonic energy. Ten young healthy volunteers were recruited and the cABRs of CV-da and CSW of their 20 ears were acquired. The response latencies, amplitudes, and frequency-domain analytic results were compared pairwisely between stimuli. The response amplitudes were significantly greater for CSW and the latencies were significantly shorter for CSW. The latency-intensity functions were also greater for CSW. For CSW, adjustments of energy component can be made without causing biased changes to the other. CSW may be used in future basic research and clinical applications.


Asunto(s)
Potenciales Evocados Auditivos del Tronco Encefálico , Percepción del Habla , Estimulación Acústica , Potenciales Evocados Auditivos/fisiología , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Humanos , Fonética , Tiempo de Reacción/fisiología , Sonido , Percepción del Habla/fisiología
3.
Environ Health ; 21(1): 58, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35710478

RESUMEN

BACKGROUND: Association between smoking and sleep apnea is well-known from previous studies. However, the influence of secondhand smoke (SHS), which is a potential risk factor of obstructive sleep apnea (OSA), remains unclear. Our aim was to investigate the relationship between SHS and OSA using a meta-analysis. MATERIALS AND METHODS: For the meta-analysis, searches were performed in MEDLINE, EMBASE, and Web of Science databases on January 10, 2022, by combining various keywords including "SHS exposure" and "OSA". Data were extracted using defined inclusion and exclusion criteria. Fixed-effects model meta-analyses were used to pool risk ratio (RR) estimates with their 95% confidence intervals (CI). I2 was used to assess heterogeneity. Moreover, we performed subgroup meta-analyses of children-adults, and smoker fathers and mothers. RESULTS: In total, 267 articles were obtained through an electronic search. Twenty-six articles were included in our analysis according to the inclusion and exclusion criteria. We found evidence of an association between SHS exposure and possible OSA (RR 1.64, 95% CI 1.44-1.88). The results of the subgroup analyses showed that children passive smokers (RR 1.84, 95% CI 1.60-2.13) were at greater risks of possible OSA than adult passive smokers (RR 1.35, 95% CI 1.21-1.50). Also, significant differences were observed in mothers with smoking exposure (RR 2.61, 95% CI 1.62-4.21, p < 0.0001), as well as in fathers with smoking exposure (RR 2.15, 95% CI 0.98-4.72, p = 0.06). SHORT CONCLUSION: Our meta-analysis confirmed that SHS exposure is significantly associated with OSA. In the subgroup analyses, the association of SHS and possible OSA was significant in both children and adults, as well as in smoker mothers and fathers.


Asunto(s)
Apnea Obstructiva del Sueño , Contaminación por Humo de Tabaco , Adulto , Niño , Femenino , Humanos , Madres , Factores de Riesgo , Apnea Obstructiva del Sueño/epidemiología , Contaminación por Humo de Tabaco/efectos adversos
4.
FASEB J ; 35(10): e21915, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34496088

RESUMEN

During development, erythroid cells are generated by two waves of hematopoiesis. In zebrafish, primitive erythropoiesis takes place in the intermediate cell mass region, and definitive erythropoiesis arises from the aorta-gonad mesonephros. TALE-homeoproteins Meis1 and Pbx1 function upstream of GATA1 to specify the erythroid lineage. Embryos lacking Meis1 or Pbx1 have weak gata1 expression and fail to produce primitive erythrocytes. Nevertheless, the underlying mechanism of how Meis1 and Pbx1 mediate gata1 transcription in erythrocytes remains unclear. Here we show that Hif1α acts downstream of Meis1 to mediate gata1 expression in zebrafish embryos. Inhibition of Meis1 expression resulted in suppression of hif1a expression and abrogated primitive erythropoiesis, while injection with in vitro-synthesized hif1α mRNA rescued gata1 transcription in Meis1 morphants and recovered their erythropoiesis. Ablation of Hif1α expression either by morpholino knockdown or Crispr-Cas9 knockout suppressed gata1 transcription and abrogated primitive erythropoiesis. Results of chromatin immunoprecipitation assays showed that Hif1α associates with hypoxia-response elements located in the 3'-flanking region of gata1 during development, suggesting that Hif1α regulates gata1 expression in vivo. Together, our results indicate that Meis1, Hif1α, and GATA1 indeed comprise a hierarchical regulatory network in which Hif1α acts downstream of Meis1 to activate gata1 transcription through direct interactions with its cis-acting elements in primitive erythrocytes.


Asunto(s)
Células Eritroides/metabolismo , Eritropoyesis , Factor de Transcripción GATA1/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/metabolismo , Animales , Inmunoprecipitación de Cromatina , Eritrocitos/citología , Eritrocitos/metabolismo , Células Eritroides/citología , Eritropoyesis/genética , Factor de Transcripción GATA1/genética , Regulación del Desarrollo de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/deficiencia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide/deficiencia , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide/genética , Factor de Transcripción 1 de la Leucemia de Células Pre-B/deficiencia , Factor de Transcripción 1 de la Leucemia de Células Pre-B/genética , Transcripción Genética , Pez Cebra/sangre , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/deficiencia , Proteínas de Pez Cebra/genética
5.
JMIR Serious Games ; 8(1): e14548, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31804184

RESUMEN

BACKGROUND: Virtual reality (VR) technologies have been developed to assist education and training. Although recent research suggested that the application of VR led to effective learning and training outcomes, investigations concerning the acceptance of these VR systems are needed to better urge learners and trainees to be active adopters. OBJECTIVE: This study aimed to create a theoretical model to examine how determining factors from relevant theories of technology acceptance can be used to explain the acceptance of a novel VR-assisted mental rotation (MR) training system created by our research team to better understand how to encourage learners to use VR technology to enhance their spatial ability. METHODS: Stereo and interactive MR tasks based on Shepard and Metzler's pencil and paper test for MR ability were created. The participants completed a set of MR tasks using 3D glasses and stereoscopic display and a 6-degree-of-freedom joystick controller. Following task completion, psychometric constructs from theories and previous studies (ie, perceived ease of use, perceived enjoyment, attitude, satisfaction, and behavioral intention to use the system) were used to measure relevant factors influencing behavior intentions. RESULTS: The statistical technique of partial least squares structural equation modeling was applied to analyze the data. The model explained 47.7% of the novel, VR-assisted MR training system's adoption intention, which suggests that the model has moderate explanatory power. Direct and indirect effects were also interpreted. CONCLUSIONS: The findings of this study have both theoretical and practical importance not only for MR training but also for other VR-assisted education. The results can extend current theories from the context of information systems to educational and training technology, specifically for the use of VR-assisted systems and devices. The empirical evidence has practical implications for educators, technology developers, and policy makers regarding MR training.

6.
Sensors (Basel) ; 19(23)2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31766519

RESUMEN

In this paper, we demonstrate an innovative electromagnetic targeting system utilizing a passive magnetic-flux-concentrator for tracking endobronchoscope used in the diagnosis process of lung cancer tumors/lesions. The system consists of a magnetic-flux emitting coil, a magnetic-flux receiving electromagnets-array, and high permeability silicon-steel sheets rolled as a collar (as the passive magnetic-flux-concentrator) fixed in a guide sheath of an endobronchoscope. The emitting coil is used to produce AC magnetic-flux, which is consequently received by the receiving electromagnets-array. Due to the electromagnetic-induction, a voltage is induced in the receiving electromagnets-array. When the endobronchoscope's guide sheath (with the silicon-steel collar) travels between the emitting coil and the receiving electromagnets-arrays, the magnetic flux is concentrated by the silicon-steel collar and thereby the induced voltage is changed. Through analyzing the voltage-pattern change, the location of the silicon-steel collar with the guide sheath is targeted. For testing, a bronchial-tree model for training medical doctors and operators is used to test our system. According to experimental results, the system is successfully verified to be able to target the endobronchoscope in the bronchial-tree model. The targeting errors on the x-, y- and z-axes are 9 mm, 10 mm, and 5 mm, respectively.


Asunto(s)
Broncoscopía/instrumentación , Fenómenos Electromagnéticos , Humanos , Neoplasias Pulmonares/diagnóstico , Silicio/química , Acero/química
7.
Cell Physiol Biochem ; 46(3): 1252-1262, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29672298

RESUMEN

BACKGROUND/AIMS: Intermittent hypoxia (IH) has been shown to exert preconditioning-like cardioprotective effects. It also has been reported that IH preserves intracellular pH (pHi) during ischemia and protects cardiomyocytes against ischemic reperfusion injury. However, the exact mechanism is still unclear. METHODS: In this study, we used proton indicator BCECF-AM to analyze the rate of pHi recovery from acidosis in the IH model of rat neonatal cardiomyocytes. Neonatal cardiomyocytes were first treated with repetitive hypoxia-normoxia cycles for 1-4 days. Cells were then acid loaded with NH4Cl, and the rate of pHi recovery from acidosis was measured. RESULTS: We found that the pHi recovery rate from acidosis was much slower in the IH group than in the room air (RA) group. When we treated cardiomyocytes with Na+-H+ exchange (NHE) inhibitors (Amiloride and HOE642) or Na+-free Tyrode solution during the recovery, there was no difference between RA and IH groups. We also found intracellular Na+ concentration ([Na+]i) significantly increased after IH exposure for 4 days. However, the phenomenon could be abolished by pretreatment with ROS inhibitors (SOD and phenanathroline), intracellular calcium chelator or Na+-Ca2+ exchange (NCX) inhibitor. Furthermore, the pHi recovery rate from acidosis became faster in the IH group than in the RA group when inhibition of NCX activity. CONCLUSIONS: These results suggest that IH would induce the elevation of ROS production. ROS then activates Ca2+-efflux mode of NCX and results in intracellular Na+ accumulation. The rise of [Na+]i further inhibits the activity of NHE-mediated acid extrusion and retards the rate of pHi recovery from acidosis during IH.


Asunto(s)
Hipoxia de la Célula , Intercambiador de Sodio-Calcio/metabolismo , Sodio/metabolismo , Amilorida/farmacología , Animales , Células Cultivadas , Femenino , Guanidinas/farmacología , Concentración de Iones de Hidrógeno , Masculino , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Intercambiador de Sodio-Calcio/antagonistas & inhibidores , Sulfonas/farmacología , Superóxido Dismutasa/metabolismo
8.
Bioresour Technol ; 227: 35-43, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28013134

RESUMEN

Lignocellulosic materials, mostly from agricultural and forestry residues, provide a potential renewable resource for sustainable biorefineries. Reducing sugars can be produced only after a pre-treatment stage, which normally involves chemicals but can be biological. In this case, two steps are usually necessary: solid-state cultivation of fungi for deconstruction, followed by enzymatic hydrolysis using cellulolytic enzymes. In this research, the utilisation of solid-state bioprocessing using the fungus Trichoderma longibrachiatum was implemented as a simultaneous microbial pretreatment and in-situ enzyme production method for fungal autolysis and further enzyme hydrolysis of fermented solids. Suspending the fermented solids in water at 50°C led to the highest hydrolysis yields of 226mg/g reducing sugar and 7.7mg/g free amino nitrogen (FAN). The resultant feedstock was shown to be suitable for the production of various products including ethanol.


Asunto(s)
Reactores Biológicos/microbiología , Lignina/química , Trichoderma/metabolismo , Fermentación , Hidrólisis
9.
Springerplus ; 2(1): 33, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23450673

RESUMEN

Suitable medium for production of milk clotting enzyme (MCE) by Bacillus subtilis (natto) Takahashi in submerged liquid-state fermentation was screened, the nutrient factors affecting MCE production was optimized by response surface methodology. The MCE production by B. subtilis (natto) Takahashi was increased significantly by 428% in the optimal medium developed. The MCE was filtered and concentrated by ultrafiltration. The retentate after tandem filtration carried out with the combined membranes of MWCO 50kDa and 5 kDa showed two major bands between 25kDa and 30kDa on SDS-PAGE, and the MCA and MCA/PA improved significantly in comparison with those in the initial broth. The crude enzyme thus obtained showed MCA and MCA/PA ratio of 48,000 SU/g and 6,400, which are commensurate with those (MCA 26,667 SU/g and MCA/PA 6,667) of the commercial rennet. It had optimal pH and temperature at pH 6 and 60°C, and showed excellent pH and thermal stability.

10.
Brain Res ; 1500: 28-35, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23337618

RESUMEN

Several clinical and animal studies of different pain models reported that motor cortex stimulation (MCS) has an antinociceptive effect. In our previous study, the response of the primary somatosensory cortex (SI) to peripheral stimuli decreased after MCS. The aim of the present study was to investigate involvement of the periaqueductal gray (PAG) in this inhibitory effect of MCS. Responses of the SI to electrical stimuli applied to both forepaws of anesthetized rats were monitored to evaluate the effect of MCS. After sensory-evoked potentials (SEPs) were stable, either saline, opioid, or dopamine receptor antagonists were locally microinjected into the PAG. After drug or saline administration, MCS was applied to the forepaw area of the right motor cortex. SEPs after MCS were compared to those before MCS. In the saline group, SEPs ipsilateral to MCS decreased, but SEPs contralateral to MCS did not. The decrease in SEPs was prevented by pretreatment of the PAG with naloxone. Application of a nonspecific dopamine receptor antagonist (α-flupenthixol) to the PAG also blocked the inhibition of SEPs after MCS. Inhibition of SEPs after MCS was blocked by local application of a D1 antagonist (SCH-23390) in the PAG, but not by a D2 antagonist (eticlopride). These results suggest that the PAG participates in the inhibitory effect of MCS, and this effect of MCS may be mediated by opioid and dopamine D1 receptors within thePAG.


Asunto(s)
Potenciales Evocados/fisiología , Corteza Motora/fisiología , Neuronas/fisiología , Sustancia Gris Periacueductal/fisiología , Animales , Benzazepinas/farmacología , Antagonistas de Dopamina/farmacología , Estimulación Eléctrica , Potenciales Evocados/efectos de los fármacos , Flupentixol/farmacología , Masculino , Microinyecciones , Corteza Motora/efectos de los fármacos , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Neuronas/efectos de los fármacos , Sustancia Gris Periacueductal/efectos de los fármacos , Ratas , Ratas Long-Evans , Salicilamidas/farmacología , Corteza Somatosensorial/efectos de los fármacos , Corteza Somatosensorial/fisiología
11.
Brain Res ; 1463: 42-50, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-22607820

RESUMEN

Motor cortex stimulation (MCS) is a promising clinical procedure to help alleviate chronic pain. Animal models demonstrated that MCS is effective in lessening nocifensive behaviors. The present study explored the effects of MCS on cortical somatosensory evoked potentials (SEPs) recorded at the primary somatosensory cortex (SI) of the rat. SEPs were evoked by electrical stimulation applied to the contralateral forepaws. Effects of different intensities, frequencies, and durations of MCS were tested. MCS at ≥2V suppressed SEPs of the ipsilateral SI. Suppression lasted 120 min at an intensity of 5 V. The optimal frequency was 50 Hz, and the duration was 30s. In contrast, MCS did not affect SEPs recorded on the contralateral SI. Cortical stimulation out of the motor cortex did not induce a decrease in the ipsilateral SEPs. We also investigated involvement of the endogenous opioid system in this inhibition of SEPs induced by MCS. The opioid antagonist, naloxone (0.5 mg/kg), was administered 30 min before MCS. Application of naloxone completely prevented the inhibitory effect of MCS on ipsilateral SEPs. These results demonstrate that MCS blocked the transmission of somatosensory information to the primary somatosensory cortex, and this interference was mediated by the endogenous opioid system. This inhibitory effect on sensory transmission induced by MCS may reflect its antinociceptive effect.


Asunto(s)
Potenciales Evocados Somatosensoriales/fisiología , Corteza Motora/fisiología , Inhibición Neural/fisiología , Corteza Somatosensorial/fisiología , Animales , Regulación hacia Abajo/fisiología , Estimulación Eléctrica/métodos , Espacio Epidural/fisiología , Masculino , Ratas , Ratas Long-Evans
12.
Artículo en Inglés | MEDLINE | ID: mdl-19962446

RESUMEN

Angiogenesis is a highly regulated physiological process in animals. Angiopoietin-1 (Angpt1) induces the signaling pathways related to vessel maturation in late phase of angiogenesis, which recruits pericyte supplements to make compact interaction with vessel tubes. There are only few data showing Angpt1 functions in fish. By using degenerate primers, partial sequence (812 bp) of Angpt1 was cloned from Anguilla japonica, and deduced amino acids showed 80% similarity to those of zebrafish. Physiological functions of cloned eel Angpt1 were studied by in vitro and in vivo manipulations with gas glands (rete mirabile) taken as the tested target tissues. RT-PCR and immunofluorescent staining techniques were performed to examine the expression patterns of Angpt1 as well as VEGF-Flk. Experimental data showed that, in vitro, bFGF, PPAR beta agonist, and estradiol affected Angpt1 expression; while cobalt ions, a VEGF expression-inducer, did not affect Angpt1 expression. In vivo, expression levels of Angpt1 increased with body growth. Furthermore, Angpt1 expressions increased significantly in the late stage of gas glands in the stimulated eel. Successive expression patterns on VEGF-Flk, and Angpt1 on different development stages of gas glands were observed. Our results suggest that the original function of angiopoietin-1 on angiogenesis is conserved during evolution.


Asunto(s)
Angiopoyetina 1/genética , Anguilla/embriología , Anguilla/genética , Estructuras Animales/embriología , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Angiopoyetina 1/metabolismo , Estructuras Animales/citología , Estructuras Animales/efectos de los fármacos , Estructuras Animales/metabolismo , Animales , Tamaño Corporal , Bagres , Células Cultivadas , Cobalto/farmacología , ADN Complementario/genética , Femenino , Factor 2 de Crecimiento de Fibroblastos/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Hormonas Esteroides Gonadales/farmacología , Insulina/farmacología , Masculino , Receptores Activados del Proliferador del Peroxisoma/agonistas , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Alineación de Secuencia , Extractos de Tejidos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
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