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1.
Environ Toxicol ; 38(12): 2819-2825, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37551787

RESUMEN

Cyclizine exhibits sedation and treatment of nausea, vomiting, and motion sickness due to antihistaminic and antimuscarinic effects. Cyclizine has the potential for abuse due to the hallucinogenic and euphoric effect. The response of overdose and illegal abuse of cyclizine includes confusion, tremors, chest pain, ataxia, seizures, and lead to suicide. Macrophage plays the important role in the innate immunity. However, over activation of macrophages results in pro-inflammatory responses in peripheral tissues. In the present study, cyclizine was found to enhanced the generation of pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6. We further found that secretion of nitrogen oxide (NO) induced by cyclizine via expression of inducible nitric oxide synthases (iNOS). Cyclizine exhibited parallel stimulation of phosphorylation of nuclear factor-κB (NFκB) p65, and its up-stream factor Akt. These results indicated that the expression of pro-inflammatory cytokines, pro-inflammatory mediators, and adhesion molecules would be induced by cyclizine via activation of Akt-NFκB pathway in macrophages.


Asunto(s)
FN-kappa B , Proteínas Proto-Oncogénicas c-akt , Humanos , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ciclizina/metabolismo , Ciclizina/farmacología , Antiinflamatorios/farmacología , Macrófagos , Citocinas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Lipopolisacáridos/farmacología , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo
2.
Sensors (Basel) ; 22(7)2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-35408372

RESUMEN

Recovering and distinguishing different ionospheric layers and signals usually requires slow and complicated procedures. In this work, we construct and train five convolutional neural network (CNN) models: DeepLab, fully convolutional DenseNet24 (FC-DenseNet24), deep watershed transform (DWT), Mask R-CNN, and spatial attention-UNet (SA-UNet) for the recovery of ionograms. The performance of the models is evaluated by intersection over union (IoU). We collect and manually label 6131 ionograms, which are acquired from a low-latitude ionosonde in Taiwan. These ionograms are contaminated by strong quasi-static noise, with an average signal-to-noise ratio (SNR) equal to 1.4. Applying the five models to these noisy ionograms, we show that the models can recover useful signals with IoU > 0.6. The highest accuracy is achieved by SA-UNet. For signals with less than 15% of samples in the data set, they can be recovered by Mask R-CNN to some degree (IoU > 0.2). In addition to the number of samples, we identify and examine the effects of three factors: (1) SNR, (2) shape of signal, (3) overlapping of signals on the recovery accuracy of different models. Our results indicate that FC-DenseNet24, DWT, Mask R-CNN and SA-UNet are capable of identifying signals from very noisy ionograms (SNR < 1.4), overlapping signals can be well identified by DWT, Mask R-CNN and SA-UNet, and that more elongated signals are better identified by all models.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Recolección de Datos , Procesamiento de Imagen Asistido por Computador/métodos , Relación Señal-Ruido , Taiwán
3.
Int J Mol Sci ; 23(9)2022 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-35563070

RESUMEN

Rice (Oryza sativa L.) is an important crop worldwide. Functional rice has exhibited health benefits. The aim of this study was to use marker-assisted selection (MAS) to introgress two genes, GE (giant embryo) and OsALDH7 (aldehyde dehydrogenase, golden-like endosperm) into colored rice and obtain high yield functional rice. CNY103108 and CNY103107 are two rice lines with golden-like endosperms and giant embryos. They were used as the donor parents. CNY922401, an elite purple waxy rice line, and TNGSW26, an indica red waxy rice cultivar were used as the recurrent parents. Foreground selection of the progenies was completed using functional markers for GE and OsALDH7, and background selection was completed using molecular markers to recover the background of the recurrent parents. MAS results showed a purple functional rice population (PFR) (CNY922401/CNY103108), with the recovery rate of the recurrent parental genome as 91.3%, and a red functional rice population (RFR) (TNGSW26/CNY103107) with the recovery as 89.8%. After five-season yield trials and several antioxidant activities analyses, PFR32 and RFR13 lines, which have similar yields and antioxidant activities, were selected as the recurrent parents with a golden-like endosperm and a giant embryo. For a biofortification purpose, they can become valuable products and be adapted to the current agricultural community.


Asunto(s)
Oryza , Agricultura , Antioxidantes , Marcadores Genéticos , Oryza/genética , Fitomejoramiento/métodos
4.
Sensors (Basel) ; 21(24)2021 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-34960569

RESUMEN

Human activity recognition without equipment plays a vital role in smart home applications, freeing humans from the shackles of wearable devices. In this paper, by using the channel state information (CSI) of the WiFi signal, semi-supervised transfer learning with dynamic associate domain adaptation is proposed for human activity recognition. In order to improve the CSI quality and denoising of CSI, we carried out missing packet filling, burst noise removal, background estimation, feature extraction, feature enhancement, and data augmentation in the data pre-processing stage. This paper considers the problem of environment-independent human activity recognition, also known as domain adaptation. The pre-trained model is trained from the source domain by collecting a complete labeled dataset of all of the CSI of human activity patterns. Then, the pre-trained model is transferred to the target environment through the semi-supervised transfer learning stage. Therefore, when humans move to different target domains, a partial labeled dataset of the target domain is required for fine-tuning. In this paper, we propose a dynamic associate domain adaptation called DADA. By modifying the existing associate domain adaptation algorithm, the target domain can provide a dynamic ratio of labeled dataset/unlabeled dataset, while the existing associate domain adaptation algorithm only allows target domains with the unlabeled dataset. The advantage of DADA is that it provides a dynamic strategy to eliminate different effects on different environments. In addition, we further designed an attention-based DenseNet model, or AD, as our training network, which is modified by an existing DenseNet by adding the attention function. The solution we proposed was simplified to DADA-AD throughout the paper. The experimental results show that for domain adaptation in different domains, the accuracy of human activity recognition of the DADA-AD scheme is 97.4%. It also shows that DADA-AD has advantages over existing semi-supervised learning schemes.


Asunto(s)
Aprendizaje Automático Supervisado , Dispositivos Electrónicos Vestibles , Aclimatación , Algoritmos , Actividades Humanas , Humanos
5.
Sensors (Basel) ; 21(19)2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34640800

RESUMEN

The technique of active ionospheric sounding by ionosondes requires sophisticated methods for the recovery of experimental data on ionograms. In this work, we applied an advanced algorithm of deep learning for the identification and classification of signals from different ionospheric layers. We collected a dataset of 6131 manually labeled ionograms acquired from low-latitude ionosondes in Taiwan. In the ionograms, we distinguished 11 different classes of the signals according to their ionospheric layers. We developed an artificial neural network, FC-DenseNet24, based on the FC-DenseNet convolutional neural network. We also developed a double-filtering algorithm to reduce incorrectly classified signals. That made it possible to successfully recover the sporadic E layer and the F2 layer from highly noise-contaminated ionograms whose mean signal-to-noise ratio was low, SNR = 1.43. The Intersection over Union (IoU) of the recovery of these two signal classes was greater than 0.6, which was higher than the previous models reported. We also identified three factors that can lower the recovery accuracy: (1) smaller statistics of samples; (2) mixing and overlapping of different signals; (3) the compact shape of signals.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Relación Señal-Ruido , Taiwán
6.
Int J Mol Sci ; 22(24)2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34948165

RESUMEN

Flash flooding is a major environmental stressor affecting rice production worldwide. DT3 is a drought-tolerant, recurrent parent with a good yield, edible quality, and agronomic traits akin to those of an elite Taiwanese variety, Taiken9 (TK9). Progenies carrying Sub1A can enhance submergence stress tolerance and can be selected using the marker-assisted backcross (MAB) breeding method. For foreground selection, Sub1A and SubAB1 were utilized as markers on the BC2F1, BC3F1, and BC3F2 generations to select the submergence-tolerant gene, Sub1A. Background selection was performed in the Sub1A-BC3F2 genotypes, and the percentages of recurrent parent recovery within individuals ranged from 84.7-99.55%. BC3F3 genotypes (N = 100) were evaluated for agronomic traits, yield, and eating quality. Four of the eleven BC3F4 lines showed good yield, yield component, grain, and eating quality. Four BC3F4 lines, SU39, SU40, SU89, and SU92, exhibited desirable agronomic traits, including grain quality and palatability, consistent with those of DT3. These genotypes displayed a high survival rate between 92 and 96%, much better compared with DT3 with 64%, and demonstrated better drought tolerance compared to IR64 and IR96321-345-240. This study provides an efficient and precise MAB strategy for developing climate-resilient rice varieties with good grain quality for flood-prone regions.


Asunto(s)
Oryza/genética , Proteínas de Plantas/genética , Estrés Fisiológico/genética , Adaptación Fisiológica/genética , Sequías , Inundaciones , Genes de Plantas/genética , Genotipo , Fenotipo , Fitomejoramiento/métodos , Proteínas de Plantas/metabolismo
7.
NMR Biomed ; 33(9): e4356, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32575161

RESUMEN

Chemical exchange saturation transfer (CEST) can provide metabolite-weighted images in the clinical setting; therefore, understanding the origin of each CEST signal is essential to revealing the changes in diseases at the molecular level, which would provide further insight for diagnoses and treatments. The CEST signal at -1.6 ppm is attributed to the choline methyl group of phosphatidylcholines. The methyl groups have no exchangeable protons, so the corresponding CEST signals must result from the relayed nuclear Overhauser effect (rNOE); however, the detailed mechanism remains unclear. Cholesterol is a major component of biological membranes, and its content is closely related to the dynamics and phases of these lipids. However, cholesterol has a hydroxyl group, which could participate in proton exchange to complete the rNOE process. In this study, we used liposomes containing cholesterol and its analogs (5α-cholestane and progesterone), which presumably have similar capabilities of influencing lipid bilayers, and found that the steroid hydroxyl group is the key to inducing the rNOE at -1.6 ppm. Our results suggest that the origin of the rNOE at -1.6 ppm likely requires an intermolecular NOE between the proton of the choline methyl group and that of the cholesterol hydroxyl group, and a chemical exchange between the cholesterol hydroxyl group and bulk water. However, the phenomenon in which the rNOE at -1.6 ppm appears when the cholesterol concentration is high seems to contradict the in vivo results, suggesting a more complicated mechanism associated with the rNOE at -1.6 ppm in biological membranes.


Asunto(s)
Colesterol/química , Imagen por Resonancia Magnética , 1,2-Dipalmitoilfosfatidilcolina/química , Colestanos/química , Liposomas , Ácido Palmítico/química
8.
Crit Rev Toxicol ; 50(7): 605-639, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-33021439

RESUMEN

The inhalation of dust containing certain nickel compounds has been associated with an increased risk of lung and nasal cancers in occupational studies of workers who process or refine sulfidic nickel ores and are exposed to relatively high levels of mixtures of water-soluble, sulfidic, oxidic, and/or metallic forms of nickel. We conducted a systematic review of the potential carcinogenicity of metallic nickel, focusing on cancers of the respiratory tract. We evaluated the quality and risk of bias (RoB) of the relevant epidemiology, experimental animal, and in vitro mechanistic studies using the National Toxicology Program's Office of Health Assessment and Translation (OHAT) RoB Rating Tool. We then used a systematic review protocol based on the OHAT approach to critically assess whether metallic nickel should be considered a human respiratory carcinogen. Our evaluation of the epidemiology studies indicates that there is no substantive evidence of increased respiratory cancer risk in workers exposed predominantly to metallic nickel. Animal evidence indicates that metallic nickel does not increase the incidence of respiratory tumors in rodents exposed by inhalation. The in vitro studies are limited in value, as they bypass normal clearance mechanisms. Nevertheless, the mechanistic evidence indicates that metallic nickel is not mutagenic but can induce DNA strand breaks under certain conditions. Based on a standard framework for assessing causality, we conclude that the evidence does not support a causal relationship between metallic nickel exposure and respiratory cancer in humans.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Carcinógenos/toxicidad , Exposición por Inhalación/estadística & datos numéricos , Níquel/toxicidad , Exposición Profesional/estadística & datos numéricos , Humanos
9.
Brain Behav Immun ; 78: 105-115, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30668980

RESUMEN

Several epidemiological studies have shown associations between developmental exposure to traffic-related air pollution and increased risk for autism spectrum disorders (ASD), a spectrum of neurodevelopmental disorders with increasing prevalence rate in the United States. Though animal studies have provided support for these associations, little is known regarding possible underlying mechanisms. In a previous study we found that exposure of C57BL/6J mice of both sexes to environmentally relevant levels (250-300 µg/m3) of diesel exhaust (DE) from embryonic day 0 to postnatal day 21 (E0 to PND21) caused significant changes in all three characteristic behavioral domains of ASD in the offspring. In the present study we investigated a potential mechanistic pathway that may be of relevance for ASD-like changes associated with developmental DE exposure. Using the same DE exposure protocol (250-300 µg/m3 DE from E0 to PND21) several molecular markers were examined in the brains of male and female mice at PND3, 21, and 60. Exposure to DE as above increased levels of interleukin-6 (IL-6) in placenta and in neonatal brain. The JAK2/STAT3 pathway, a target for IL-6, was activated by STAT3 phosphorylation, and the expression of DNA methyltransferase 1 (DNMT1), a STAT3 target gene, was increased in DE-exposed neonatal brain. DNMT1 has been reported to down-regulate expression of reelin (RELN), an extracellular matrix glycoprotein important in regulating the processes of neuronal migration. RELN is considered an important modulator for ASD, since there are several polymorphisms in this gene linked to the disease, and since lower levels of RELN have been reported in brains of ASD patients. We observed decreased RELN expression in brains of the DE-exposed mice at PND3. Since disorganized patches in the prefrontal cortex have been reported in ASD patients and disrupted cortical organization has been found in RELN-deficient mice, we also assessed cortical organization, by labeling cells expressing the lamina-specific-markers RELN and calretinin. In DE-exposed mice we found increased cell density in deeper cortex (lamina layers VI-IV) for cells expressing either RELN or calretinin. These findings demonstrate that developmental DE exposure is associated with subtle disorganization of the cerebral cortex at PND60, and suggest a pathway involving IL-6, STAT3, and DNMT1 leading to downregulation of RELN expression that could be contributing to this long-lasting disruption in cortical laminar organization.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/metabolismo , Corteza Cerebral/fisiopatología , Proteínas de la Matriz Extracelular/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Serina Endopeptidasas/metabolismo , Emisiones de Vehículos/toxicidad , Contaminantes Atmosféricos/toxicidad , Animales , Encéfalo/metabolismo , Calbindina 2 , Moléculas de Adhesión Celular Neuronal/genética , Corteza Cerebral/metabolismo , Proteínas de la Matriz Extracelular/genética , Femenino , Exposición por Inhalación/efectos adversos , Interleucina-6/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/genética , Corteza Prefrontal/metabolismo , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Proteína Reelina , Serina Endopeptidasas/genética
10.
Small ; 14(13): e1703888, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29450966

RESUMEN

The silver-embedded gelatin (AgG) thin film produced by the solution method of metal salts dissolved in gelatin is presented. Its simple fabrication method ensures the uniform distribution of Ag dots. Memory devices based on AgG exhibit good device performance, such as the ON/OFF ratio in excess of 105 and the coefficient of variation in less of 50%. To further investigate the position of filament formation and the role of each element, current sensing atomic force microscopy (CSAFM) analysis as well as elemental line profiles across the two different conditions in the LRS and HRS are analyzed. The conductive and nonconductive regions in the current map of the CSAFM image show that the conductive filaments occur in the AgG layer around Ag dots. The migration of oxygen ions and the redox reaction of carbon are demonstrated to be the driving mechanism for the resistive switching of AgG memory devices. The results show that dissolving metal salts in gelatin is an effective way to achieve high-performance organic-electronic applications.

11.
BMC Cardiovasc Disord ; 18(1): 214, 2018 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-30482161

RESUMEN

BACKGROUND: Sclerostin is known to be a canonical Wnt/ß-catenin signaling pathway inhibitor, while the Wnt/ß-catenin signaling pathway is proposed to be involved in the development of arterial stiffness. This study aims to investigate the relationship between serum sclerostin levels and carotid-femoral pulse wave velocity (cfPWV) among hypertensive patients. METHODS: Fasting blood samples were obtained from 105 hypertensive patients. Patients with cfPWV values of > 10 m/s were classified in the high arterial stiffness group, whereas those with cfPWV values of ≤10 m/s were assigned to the low arterial stiffness group. Serum sclerostin and Dickkopf-1 (DKK1) levels were quantified using commercially available enzyme-linked immunosorbent assays. RESULTS: Thirty-six hypertensive patients (34.3%) who belonged to the high arterial stiffness group were generally older (p < 0.001), presented with lower estimated glomerular filtration rates (eGFR, p = 0.014), higher incidence of diabetes mellitus (p = 0.030), average systolic blood pressures (SBP, p = 0.013), pulse pressure (p = 0.026), serum creatinine levels (p = 0.013), intact parathyroid hormone levels (iPTH, p = 0.003), and sclerostin levels (p < 0.001) than their counterparts in the low arterial stiffness group. A multivariable logistic regression analysis identified sclerostin as an independent predictor of arterial stiffness in hypertensive patients (odds ratio, 1.042; 95% confidence interval (CI), 1.017-1.068; p = 0.001). Multivariable forward stepwise linear regression analysis also showed that serum sclerostin level (ß = 0.255, adjusted R2 change: 0.146, p = 0.003) was positively associated with cfPWV values in patients with hypertension. CONCLUSIONS: In this study, serum sclerostin level, but not DKK1, is found to be positively correlated with cfPWV values and is identified as an independent predictor of arterial stiffness in hypertensive patients after adjusting for significant confounders.


Asunto(s)
Proteínas Morfogenéticas Óseas/sangre , Hipertensión/sangre , Hipertensión/fisiopatología , Rigidez Vascular , Proteínas Adaptadoras Transductoras de Señales , Factores de Edad , Anciano , Biomarcadores/sangre , Comorbilidad , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Marcadores Genéticos , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Péptidos y Proteínas de Señalización Intercelular/sangre , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso , Factores de Riesgo , Taiwán , Regulación hacia Arriba
12.
Part Fibre Toxicol ; 15(1): 18, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29678176

RESUMEN

BACKGROUND: Escalating prevalence of autism spectrum disorders (ASD) in recent decades has triggered increasing efforts in understanding roles played by environmental risk factors as a way to address this widespread public health concern. Several epidemiological studies show associations between developmental exposure to traffic-related air pollution and increased ASD risk. In rodent models, a limited number of studies have shown that developmental exposure to ambient ultrafine particulates or diesel exhaust (DE) can result in behavioral phenotypes consistent with mild ASD. We performed a series of experiments to determine whether developmental DE exposure induces ASD-related behaviors in mice. RESULTS: C57Bl/6J mice were exposed from embryonic day 0 to postnatal day 21 to 250-300 µg/m3 DE or filtered air (FA) as control. Mice exposed developmentally to DE exhibited deficits in all three of the hallmark categories of ASD behavior: reduced social interaction in the reciprocal interaction and social preference tests, increased repetitive behavior in the T-maze and marble-burying test, and reduced or altered communication as assessed by measuring isolation-induced ultrasonic vocalizations and responses to social odors. CONCLUSIONS: These findings demonstrate that exposure to traffic-related air pollution, in particular that associated with diesel-fuel combustion, can cause ASD-related behavioral changes in mice, and raise concern about air pollution as a contributor to the onset of ASD in humans.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Trastorno Autístico/inducido químicamente , Conducta Animal/efectos de los fármacos , Exposición por Inhalación/efectos adversos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Emisiones de Vehículos/toxicidad , Animales , Animales Recién Nacidos , Trastorno Autístico/fisiopatología , Modelos Animales de Enfermedad , Femenino , Edad Gestacional , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Endogámicos C57BL , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología
13.
Biosci Biotechnol Biochem ; 79(1): 88-96, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25209380

RESUMEN

Asthma is a major public health concern. Its greatest risk factor is house dust mite (HDM). Dermatophagoides microceras (Der m) is a type of HDM, and in central Taiwan, there is approximately 80% prevalence of sensitization to Der m. FIP-fve is a fungal immunomodulatory protein (FIP) isolated from the fungus Flammulina velutipes, and exhibits anti-inflammatory properties. To investigate whether FIP-fve affects Der m-induced asthma and inflammation, we evaluated hyper-responsiveness (AHR), pathological changes, and cytokines in mice. We demonstrated that oral FIP-fve decreased Der m-induced airway AHR, airway inflammation, cell infiltration, and expression of cytokines in the bronchoalveolar lavage fluid of Balb/c mice. The results of this study suggest that FIP-fve suppresses asthma, inflammation, and respiratory pathogenesis stimulated by Der m. FIP-fve is able to maintain immunomodulatory activity even in simulated gastric fluid and intestinal fluid. FIP-fve could be a safe and stable agent for suppression of allergic asthma.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Asma/tratamiento farmacológico , Flammulina/química , Cuerpos Fructíferos de los Hongos/química , Proteínas Fúngicas/farmacología , Hipersensibilidad/tratamiento farmacológico , Alérgenos/inmunología , Animales , Antiinflamatorios no Esteroideos/aislamiento & purificación , Asma/inmunología , Asma/patología , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Femenino , Proteínas Fúngicas/aislamiento & purificación , Humanos , Hipersensibilidad/inmunología , Hipersensibilidad/patología , Interleucina-6/antagonistas & inhibidores , Interleucina-6/biosíntesis , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/patología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/patología , Ratones , Ratones Endogámicos BALB C , Infiltración Neutrófila/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Neutrófilos/patología , Pletismografía , Estabilidad Proteica , Pyroglyphidae/química , Pyroglyphidae/inmunología , Sistema Respiratorio/efectos de los fármacos , Sistema Respiratorio/inmunología , Sistema Respiratorio/patología
14.
Analyst ; 139(9): 2039-46, 2014 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-24151636

RESUMEN

In this paper we present two compact, quantum cascade laser absorption spectroscopy based, sensors developed for trace substance detection in gases and liquids. The gas sensor, in its most integrated version, represents the first system combining a quantum cascade laser and a quantum cascade detector. Furthermore, it uses a toroidal mirror cell with a volume of only 40 cm(3) for a path length of up to 4 m. The analytical performance is assessed by the measurements of isotope ratios of CO2 at ambient abundance. For the (13)CO2/(12)CO2 isotope ratio, a measurement precision of 0.2‰ is demonstrated after an integration time of 600 s. For the liquid sensor, a microfluidic system is used to extract cocaine from saliva into a solvent (PCE) transparent in the mid-infrared. This system is bonded on top of a Si/Ge waveguide and the concentration of cocaine in PCE is measured through the interaction of the evanescent part of the waveguide optical mode and the solvent flowing on top. A detection limit of <100 µg mL(-1) was achieved with this system and down to 10 µg mL(-1) with a simplified, but improved system.

15.
ACS Omega ; 9(1): 1077-1083, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38222652

RESUMEN

With the growing concern over the adverse effects of environmental pollution on human health, the combination of environmentally friendly and nontoxic biomaterials with metal oxide semiconductor materials for electronic devices has emerged as a prominent trend in current research. In this study, we utilized 150 mg apple biotemplates to assist in the hydrothermal synthesis of ZnO nanospheres. It successfully achieved high sensitivity for detecting 35 and 350 ppb NO2 at room temperature, with responses of 13.74 and 132.44%, respectively. Simultaneously, the 5-cycle repeatability and multiple-gas selectivity exhibited significant improvements. The ZnO nanospheres demonstrated enhanced sensing performance compared to pure ZnO nanorods, which is attributed to the following mechanisms: reason I, the modified surface morphology increasing the surface-to-volume ratio; reason II, an increase in oxygen vacancies, leading to reduced crystallinity and a higher electron concentration; reason III, incorporation of carbon elements on the nanostructure surface to increase active sites. The novel gas sensor assisted by the apple pectin biotemplate offers a promising solution for NO2 gas detection, featuring low operating temperatures, low concentrations, and high response sensitivity.

16.
Anal Chem ; 85(15): 7558-65, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23815182

RESUMEN

We present a portable microsystem to quantitatively detect cocaine in human saliva. In this system, we combine a microfluidic-based multiphase liquid-liquid extraction method to transfer cocaine continuously from IR-light-absorbing saliva to an IR-transparent solvent (tetrachloroethylene) with waveguide IR spectroscopy (QC-laser, waveguide, detector) to detect the cocaine on-chip. For the fabrication of the low-cost polymer microfluidic chips a simple rapid prototyping technique based on Scotch-tape masters was further developed and applied. To perform the droplet-based liquid-liquid extraction, we designed and integrated a simple and robust droplet generation method based on the capillary focusing effect within the device. Compared to well-characterized and commonly used microfluidic H-filters, our system showed at least two times higher extraction efficiencies with potential for further improvements. The current liquid-liquid extraction method alone can efficiently extract cocaine and pre-concentrate the analytes in a new solvent. Our fully integrated optofluidic system successfully detected cocaine in real saliva samples spiked with the drug (500 µg/mL) and allowed real time measurements, which makes this approach suitable for point-of-care applications.


Asunto(s)
Cocaína/análisis , Cocaína/aislamiento & purificación , Extracción Líquido-Líquido/métodos , Técnicas Analíticas Microfluídicas/métodos , Saliva/química , Espectrofotometría Infrarroja/métodos , Métodos Analíticos de la Preparación de la Muestra , Cocaína/química , Humanos
17.
Part Fibre Toxicol ; 10(1): 59, 2013 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-24279743

RESUMEN

BACKGROUND: Fine particulate air pollution (PM2.5) is a global health concern, as exposure to PM2.5 has consistently been found to be associated with increased cardiovascular morbidity and mortality. Although adult exposure to traffic related PM2.5, which is largely derived from diesel exhaust (DE), has been associated with increased cardiac hypertrophy, there are limited investigations into the potential effect of in utero and early life exposure on adult susceptibility to heart disease. In this study, we investigate the effect of in utero and early life exposure to DE on adult susceptibility to heart failure. METHODS: Female C57BL/6 J mice were exposed to either filtered air (FA) or DE for 3 weeks (≈ 300 µg/m3 PM2.5 for 6 hours/day, 5 days/week) and then introduced to male breeders for timed matings. Female mice were exposed to either FA or DE throughout pregnancy and until offspring were 3 weeks of age. Offspring were then transferred to either FA or DE for an additional 8 weeks of exposure. At 12 weeks of age, male offspring underwent a baseline echocardiographic assessment, followed by a sham or transverse aortic constriction (TAC) surgery to induce pressure overload. Following sacrifice three weeks post surgery, ventricles were processed for histology to assess myocardial fibrosis and individual cardiomyocyte hypertrophy. mRNA from lung tissue was isolated to measure expression of inflammatory cytokines IL6 and TNFα. RESULTS: We observed that mice exposed to DE during in utero and early life development have significantly increased susceptibility to cardiac hypertrophy, systolic failure, myocardial fibrosis, and pulmonary congestion following TAC surgery compared to FA control, or adult DE exposed mice. In utero and early life DE exposure also strongly modified the inflammatory cytokine response in the adult lung. CONCLUSIONS: We conclude that exposure to diesel exhaust air pollution during in utero and early life development in mice increases adult susceptibility to heart failure. The results of this study may imply that the effects of air pollution on cardiovascular disease in human populations may be strongly mediated through a 'fetal origins' of adult disease pathway. Further investigations on this potential pathway of disease are warranted.


Asunto(s)
Exposición a Riesgos Ambientales , Insuficiencia Cardíaca/inducido químicamente , Efectos Tardíos de la Exposición Prenatal , Emisiones de Vehículos , Animales , Citocinas/metabolismo , Femenino , Ratones , Embarazo
18.
ACS Omega ; 8(13): 12387-12392, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37033830

RESUMEN

In recent years, due to the environmental impact caused by electronic waste, decomposable components have become one of the most important topics in the world. In this study, the carrageenan material extracted from red algae was used as the resistance-switching layer of electronic components, and potassium was added to the carrageenan as a substrate (CK). CK has the advantages of excellent mechanical properties, transparency, and decomposability. In addition, the In/carrageenan/Ag/CK (ICACK) device exhibits good memory properties with a high ON/OFF ratio exceeding 107 and a retention time exceeding 104 s. Due to the doping of potassium ions, the ICACK element has a fairly good bending performance. Although bending or stretching under a small radius of curvature will not have a great impact on the electrical performance, it shows that in the future wearable or good potential in the field of implantable devices.

19.
Jpn J Nurs Sci ; 20(3): e12531, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36960772

RESUMEN

AIMS: Chemotherapy-induced peripheral neuropathy limits cancer survivors' compliance with chemotherapy and impaired function. This study aimed to examine separate impacts of clinician-assessed, patient-reported sensory and motor chemotherapy-induced peripheral neuropathy on physical/role function and functional interference in advanced colorectal cancer survivors receiving chemotherapy. METHODS: A cross-sectional, correlational design utilizing convenience sampling enrolled 75 stage III or IV colorectal cancer adults undergoing chemotherapy. Participants filled out the Patient Neurotoxicity Questionnaire, Identification Pain Questionnaire, and Peripheral Neuropathy Scale. Then, a trained research nurse conducted a brief neurological assessment using the Total Neuropathy Scale - clinical version. RESULTS: The prevalence of sensory and motor chemotherapy-induced peripheral neuropathy was from 34.7% to 54.7% and from 16.0% to 17.3%, respectively. Further, 20% of participants suffered from neuropathic pain. A low correlation between clinician-assessed and patient-reported chemotherapy-induced peripheral neuropathy was detected. The function was significantly impacted by patient-reported motor chemotherapy-induced peripheral neuropathy. CONCLUSIONS: This study was superior in utilizing the brief and valid patient-reported and clinician-assessed tools to measure sensory and motor chemotherapy-induced peripheral neuropathy. Moreover, the identification of patient-reported motor symptoms has the largest influence on function in advanced colorectal cancer survivors. Nurses may use the brief and easily administered tools in clinical settings for effective screening and early detection of motor and sensory chemotherapy-induced peripheral neuropathy to prevent functional decline in advanced colorectal cancer survivors. However, this study was still limited because of the cross-sectional design, small sample size, sample heterogeneity, and recruiting participants from only one medical center.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Enfermedades del Sistema Nervioso Periférico , Adulto , Humanos , Antineoplásicos/efectos adversos , Estudios Transversales , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Sobrevivientes , Medición de Resultados Informados por el Paciente
20.
Opt Lett ; 37(14): 2883-5, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-22825166

RESUMEN

Mid-infrared photonics in silicon needs low-loss integrated waveguides. While monocrystalline germanium waveguides on silicon have been proposed, experimental realization has not been reported. Here we demonstrate a germanium strip waveguide on a silicon substrate. It is designed for single mode transmission of light in transverse magnetic (TM) polarization generated from quantum cascade lasers at a wavelength of 5.8 µm. The propagation losses were measured with the Fabry-Perot resonance method. The lowest achieved propagation loss is 2.5 dB/cm, while the bending loss is measured to be 0.12 dB for a 90° bend with a radius of 115 µm.

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