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1.
Chem Biodivers ; 20(8): e202300793, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37485567

RESUMEN

The utilization of rhizomes from the genus Atractylodes has been challenging due to their closely related origins. In this study, we developed an analytical strategy to differentiate Atractylodes lancea (A. lancea), Atractylodes chinensis (A. chinensis), Atractylodes japonica (A. japonica), and Atractylodes macrocephala (A. macrocephala), and compared their volatile compositions. Gas chromatography-mass spectrometry (GC/MS) was used to analyze the volatile profiles of essential oils extracted from 59 batches of samples. Chemometric methods enabled a better understanding of the differences in volatile oils between the four species and identified significant components affecting their classification and quality. A total of 50 volatile components were identified from the essential oils by GC/MS. Unsupervised and supervised chemometric analyses accurately distinguished A. lancea, A. chinensis, A. japonica, and A. macrocephala. Furthermore, five characteristic chemical markers, namely hinesol, ß-eudesmol, atractylon, atractylodin and atractylenolide I, were obtained, and their respective percentage contents in individual species and samples were determined. This study provides a valuable reference for the quality evaluation of medicinal plants with essential oils and holds significance for species differentiation and the rational clinical application of Atractylodes herbs.


Asunto(s)
Atractylodes , Aceites Volátiles , Plantas Medicinales , Cromatografía de Gases y Espectrometría de Masas , Plantas Medicinales/química , Atractylodes/química , Quimiometría , Aceites Volátiles/química
2.
Ecotoxicol Environ Saf ; 247: 114209, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36308880

RESUMEN

BACKGROUND: Metal exposure were assumed to be closely related with declined renal function, but the conclusions were controversial. We employed diverse statistical models and assessed the association between metal mixture exposure and mild renal impairment. METHODS: A total of 13 plasma metals were measured in 896 general population from Southern China. Subjects with estimated glomerular filtration rate within 60-89 ml/min/1.73 m2 and urinary albumin-creatinine ratio <30 mg/g creatinine were defined as mild renal impairment (MRI). RESULTS: About 31.47 % participants showed MRI. In the multivariate logistic regression models, compared with the first quartile, high levels of arsenic and molybdenum (the fourth quartile) were both associated with MRI, and the ORs (95 % CI) were 1.68 (1.05, 2.68) and 2.21 (1.40, 3.48), respectively. Their predominant roles were identified by the weighted quantile regression (WQS). Besides, restricted cubic spline analysis verified the relationship between molybdenum level and increased MRI risk in a linear and dose-response manner. CONCLUSION: High levels of arsenic and molybdenum might be independent risk factors of MRI, and they showed combined effect. Our findings might provide vigorous evidence in preventing mild decline in renal function.


Asunto(s)
Arsénico , Humanos , Molibdeno , Creatinina , Metales , Tasa de Filtración Glomerular , China/epidemiología
3.
Environ Geochem Health ; 40(5): 2071-2086, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29549472

RESUMEN

Intense mining, smelting, and tailing activities of polymetallic ore deposits have affected the environment in Nandan County, Guangxi, China. Samples of particulates with aerodynamic diameters low or equal 10 µm (PM10) were collected in Nandan County to investigate the concentrations of and health risks posed by 17 metals and metalloids in the PM10. The metal and metalloid concentrations were lower than those found in other industrial cities. The mean Cr concentration was 7.48 ng/m3. Significant higher metal and metalloid concentrations were found in PM10 from mining areas (Dachang and Chehe) than from the control area (Liuzhai) (p < 0.05). Principal component analysis indicated that the main sources of Ba, Co, Cr, Fe, K, Mg, Mo, Na, and Sr were resuspension of the soil produced through mineral erosion, the main sources of As, Cd, Cu, Pb, Sb, and Zn were smelting and mining activities, and the main source of Ni was fossil fuel combustion. Higher non-carcinogenic and carcinogenic risks were posed in Dachang and Chehe than in Liuzhai. The non-carcinogenic risks posed to adults and children by individual metals and metalloids in PM10 at all the sites were low, but the non-carcinogenic risks posed to children by all the metals and metalloids together exceeded the safe level (i.e., risk value > 1). The carcinogenic risks posed by Cd, Ni, and Pb were negligible at all sites, while As, Co, and Cr posed potential carcinogenic risks to the residents.


Asunto(s)
Monitoreo del Ambiente/métodos , Metaloides/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Adulto , Niño , China , Ciudades , Polvo/análisis , Humanos , Minería , Medición de Riesgo/métodos , Suelo/química
4.
Sci Rep ; 14(1): 10181, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702395

RESUMEN

Image recognition is a pervasive task in many information-processing environments. We present a solution to a difficult pattern recognition problem that lies at the heart of experimental particle physics. Future experiments with very high-intensity beams will produce a spray of thousands of particles in each beam-target or beam-beam collision. Recognizing the trajectories of these particles as they traverse layers of electronic sensors is a massive image recognition task that has never been accomplished in real time. We present a real-time processing solution that is implemented in a commercial field-programmable gate array using high-level synthesis. It is an unsupervised learning algorithm that uses techniques of graph computing. A prime application is the low-latency analysis of dark-matter signatures involving metastable charged particles that manifest as disappearing tracks.

5.
Clin Breast Cancer ; 24(6): 552-561, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38641470

RESUMEN

OBJECTIVE: The association of FGFR2-rs13387042 polymorphism with breast cancer (BC) susceptibility in women remains inconclusive due to varying reports. In this study, we conducted a meta-analysis to explore the relationship between FGFR2-rs13387042 polymorphism and susceptibility to BC. METHODS: Relevant literature were acquired through searches across multiple databases. Odds ratio (OR) values were pooled to assess the risk of BC for different alleles and genotypes. The heterogeneity among the included literature was evaluated. Sensitivity analysis was used to verify the stability of the results. Egger's linear regression test was used to assess the significance of publication bias of the included literature. RESULTS: A total of 17 publications were included, encompassing 122,607 cases and 175,966 controls. There was significantly increased risk of BC for allele A compared with G (OR = 1.15, 95% CI = 1.14-1.67, P < .001), genotype AA compared with GG (OR = 1.34, 95% CI = 1.29-1.38, P < .001), and genotype GA compared with GG (OR = 1.19, 95% CI = 1.12-1.26, P < .001). Both Egger's test and funnel plot indicated the presence of publication bias. After adjusting potential publication bias by the trim-and-fill method, the comparison of allele A versus G (OR = 1.15, 95% CI = 1.13-1.17, P < .001), genotype AA versus GG (OR = 1.32, 95% CI = 1.28-1.37, P < .001), and genotype GA versus GG (OR = 1.15, 95% CI = 1.09-1.22, P < .001) remained statistically significant. In various subgroups, the allele A showed significantly higher risk of BC upon allele G in estrogen receptor (ER) positive BC, ER negative BC, progesterone receptor (PR) positive BC, PR negative BC, triple-negative BC, pathological grade I BC, grade II BC, and grade III breast cancer. The subsequent sensitivity analysis suggested the above findings stable and reliable. CONCLUSION: In this study, we found that the allele A of the FGFR2-rs13387042 polymorphism is associated with increased risk of developing breast cancer. This study underscores its potential as a genetic marker for personalized risk assessment and targeted interventions.


Asunto(s)
Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Humanos , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Alelos , Genotipo , Estudios de Casos y Controles , Factores de Riesgo
6.
Int Immunopharmacol ; 128: 111520, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38199194

RESUMEN

Periodontal ligament stem cells (PDLSCs), which are considered promising stem cells for regeneration of periodontal bony tissue, can also manipulate alveolar bone remodeling by exosomes. In this study, we investigated interactions between PDLSCs under osteogenic differentiation and osteoclast precursors. The results showed that conditioned medium from PDLSCs under 5d osteogenic induction promoted osteoclastogenesis of RAW264.7 cells. The exosomes extracted from those conditioned media showed similar effects on osteoclastogenesis. Furthermore, exosomes from PDLSCs under 5d of osteogenic induction showed significantly high expression of circ_0000722, compared with exosomes from PDLSCs before osteogenic induction. Downregulation of circ_0000722 significantly attenuated the effect of PDLSC-derived exosomes on the osteoclastogenesis of RAW264.7 cells. Our findings suggested that exosomal circ_0000722 derived from periodontal ligament stem cells undergoing osteogenic differentiation might promote osteoclastogenesis by upregulating TRAF6 expression and activating downstream NF-κB and AKT signaling pathways.


Asunto(s)
Osteogénesis , Ligamento Periodontal , Células Cultivadas , Células Madre , Diferenciación Celular
7.
Int Immunopharmacol ; 138: 112452, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38943972

RESUMEN

Peripheral nerve injury seriously endangers human life and health, but there is no clinical drug for the treatment of peripheral nerve injury, so it is imperative to develop drugs to promote the repair of peripheral nerve injury. Erythropoietin (EPO) not only has the traditional role of promoting erythropoiesis, but also has a tissue-protective effect. Over the past few decades, researchers have confirmed that EPO has neuroprotective effects. However, side effects caused by long-term use of EPO limited its clinical application. Therefore, EPO derivatives with low side effects have been explored. Among them, ARA290 has shown significant protective effects on the nervous system, but the biggest disadvantage of ARA290, its short half-life, limits its application. To address the short half-life issue, the researchers modified ARA290 with thioether cyclization to generate a thioether cyclized helical B peptide (CHBP). ARA290 and CHBP have promising applications as peptide drugs. The neuroprotective effects they exhibit have attracted continuous exploration of their mechanisms of action. This article will review the research on the role of EPO, ARA290 and CHBP in the nervous system around this developmental process, and provide a certain reference for the subsequent research.


Asunto(s)
Eritropoyetina , Fármacos Neuroprotectores , Traumatismos de los Nervios Periféricos , Eritropoyetina/uso terapéutico , Humanos , Traumatismos de los Nervios Periféricos/tratamiento farmacológico , Animales , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/farmacología , Péptidos/uso terapéutico , Péptidos/farmacología , Oligopéptidos
8.
Chin Med ; 18(1): 148, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950271

RESUMEN

BACKGROUND: Panax japonicus C.A. Meyer (Zhujieshen) is widely used in traditional medicine as a tonic hemostatic and anti-inflammatory agent in China, Japan, and Korea. Furthermore, it is used as an important substitute for ginseng roots by minority ethnic groups in China. The purpose of this review is to summarize the latest research on Zhujieshen in recent years, aiming at providing a systematic overview of the current knowledge, and perspectives for future research and exploitation. MAIN BODY: This review examines the research advances in botanical profile, phytochemicals, pharmacology, pharmacokinetics, and authentication of Zhujieshen. Various compounds have been reported as active components, mainly including saponins, volatile oils, and polysaccharides. Pharmacological investigations have demonstrated that Zhujieshen is an important herb with significant bioactivities, such as anti-inflammatory, hepato-protective, cardio-protective, neuro-protective, anti-tumor, anti-oxidant, anti-thrombotic and immunomodulatory activities. CONCLUSION: Currently, research on Zhujieshen is in the preliminary stages, and further research is required to understand the active compounds present and mechanisms of action. We hope that this comprehensive review of Zhujieshen will serve as a background for future research and exploitation.

9.
Huan Jing Ke Xue ; 44(12): 6744-6753, 2023 Dec 08.
Artículo en Zh | MEDLINE | ID: mdl-38098400

RESUMEN

Lakes on the Inner Mongolia Plateau, located in the ecologically fragile area of the northern border of China, play a very important role in regulating the regional climate and ecological environment and maintaining biodiversity. Owing to the dual influence of natural factors and human factors, the lake water environment in Inner Mongolia is facing challenges. To clarify the overall water quality of lakes in Inner Mongolia, based on the water quality data of typical lakes in Inner Mongolia in autumn 2019(October-November) and summer 2021(July-August), the temporal and spatial variation in water quality was discussed, and the influence of different indexes on lake water quality was analyzed, and the key factors affecting lake water quality were identified. The results showed as follows:① the spatiotemporal distribution of multiple physicochemical indices of typical lakes in Inner Mongolia were different in the two seasons. On the time scale, the concentration of ammonia nitrogen(NH4+-N) and nitrite nitrogen(NO2--N) were lower in autumn than that in summer, whereas dissolved oxygen(DO) was higher in autumn than that in summer. On the spatial scale, the concentrations of total phosphorus(TP), total nitrogen(TN), chemical oxygen demand(COD), and salinity(Sal) and other indicators in the southwest lakes of Inner Mongolia were higher than those of lakes in the northeast, but the DO index showed the opposite trend. ② Dissolved total solids(TDS) was the main characteristic factor of water quality of typical lakes in Inner Mongolia. ③ The spatiotemporal distribution of lake water quality index(WQI) was significantly different. The lake water quality level decreased with the increase in TDS, and the lake water quality was better in autumn than that in summer.

10.
Front Oncol ; 13: 1190706, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37771438

RESUMEN

Objective: To profile the serum metabolites and metabolic pathways in colorectal cancer (CRC) patients associated with spleen-deficiency and qi-stagnation syndrome (SDQSS) or damp-heat syndrome (DHS). Methods: From May 2020 to January 2021, CRC patients diagnosed with traditional Chinese medicine (TCM) syndromes of SDQSS or DHS were enrolled. The clinicopathological data of the SDQSS and DHS groups were compared. The serum samples were analyzed by liquid chromatography-mass spectrometry (LC-MS). The variable importance in the projection >1, fold change ≥3 or ≤0.333, and P value ≤0.05 were used to identify differential metabolites between the two groups. Furthermore, areas under the receiver operating characteristic (ROC) curve > 0.9 were applied to select biomarkers with good predictive performance. The enrichment metabolic pathways were searched through the database of Kyoto Encyclopedia of Genes and Genomes. Results: 60 CRC patients were included (30 SDQSS and 30 DHS). The level of alanine aminotransferase was marginally significantly higher in the DHS group than the SDQSS group (P = 0.051). The other baseline clinicopathological characteristics were all comparable between the two groups. 23 differential serum metabolites were identified, among which 16 were significantly up-regulated and 7 were significantly down-regulated in the SDQSS group compared with the DHS group. ROC curve analysis showed that (S)-3-methyl-2-oxopentanoic acid, neocembrene, 1-aminocyclopropanecarboxylic acid, 3-methyl-3-hydroxypentanedioate, and nicotine were symbolic differential metabolites with higher predictive power. The top five enrichment signalling pathways were valine, leucine and isoleucine biosynthesis; lysosome; nicotine addiction; fructose and mannose metabolism; and pertussis. Conclusion: Our study identifies the differential metabolites and characteristic metabolic pathways among CRC patients with SDQSS or DHS, offering the possibility of accurate and objective syndrome differentiation and TCM treatment for CRC patients.

11.
Sci Adv ; 9(24): eadg6670, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37327328

RESUMEN

Wound healing is a dynamic process with multiple phases. Rapid profiling and quantitative characterization of inflammation and infection remain challenging. We report a paper-like battery-free in situ AI-enabled multiplexed (PETAL) sensor for holistic wound assessment by leveraging deep learning algorithms. This sensor consists of a wax-printed paper panel with five colorimetric sensors for temperature, pH, trimethylamine, uric acid, and moisture. Sensor images captured by a mobile phone were analyzed by neural network-based machine learning algorithms to determine healing status. For ex situ detection via exudates collected from rat perturbed wounds and burn wounds, the PETAL sensor can classify healing versus nonhealing status with an accuracy as high as 97%. With the sensor patches attached on rat burn wound models, in situ monitoring of wound progression or severity is demonstrated. This PETAL sensor allows early warning of adverse events, which could trigger immediate clinical intervention to facilitate wound care management.


Asunto(s)
Quemaduras , Cicatrización de Heridas , Ratas , Animales , Aprendizaje Automático , Algoritmos
12.
Front Oncol ; 12: 1082850, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36686764

RESUMEN

Introduction: The impact of rib invasion on the non-small cell lung cancer (NSCLC) T classifications remains unclear. Our study aims to verify the impact of rib invasion on survival in patients with NSCLC through multicenter data from the Surveillance, Epidemiology, and End Results (SEER) database, and proposed a more appropriate pT for the forthcoming 9th tumor-node-metastasis (TNM) classifications. Method: The SEER database was used to collect T2b-4N0-2M0 NSCLC cases from the period of 2010-2015 according to the 7th TNM classification system. Subsequently, the T classification was restaged according to the 8th TNM classification system based on the following codes: tumor size and tumor extension. Cases with T1-2 disease and incomplete clinicopathological information were excluded. Finally, 6479 T3 and T4 NSCLC patients were included in the present study and divided into a rib invasion group (n = 131), other pT3 group (n = 3835), and pT4 group (n = 2513). Propensity-score matching (PSM) balanced the known confounders of the prognosis, resulting in two sets (rib invasion group vs. other pT3 and pT4 group). Overall survival (OS) and cancer-specific survival (CSS) were investigated using Kaplan-Meier survival curves, and predictive factors of OS and CSS were assessed by Cox regression. Result: Survival outcomes of the rib invasion group were worse than the other pT3 group (OS: 40.5% vs. 46.5%, p = 0.035; CSS: 49.2% vs. 55.5%, p = 0.047), but comparable to the pT4 group (OS: 40.5% vs. 39.9%, p = 0.876; CSS: 49.2% vs. 46.3%, p = 0.659). Similar results were obtained after PSM. Multivariate analyses for all patients revealed that age at diagnosis, gender, N stage, T stage, surgical modalities, and adjuvant therapy had a predictive value for the prognosis. Conclusion: The rib invasion group had a worse prognosis than the other pT3 groups, but was similar to the pT4 group. Our recommendation is to change the classification of rib invasion to pT4 disease and further validate this in the forthcoming 9th TNM classification.

13.
Nanomicro Lett ; 14(1): 56, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-35122157

RESUMEN

Environmentally friendly degradable sensors with both hazardous gases and pressure efficient sensing capabilities are highly desired for various promising applications, including environmental pollution monitoring/prevention, wisdom medical, wearable smart devices, and artificial intelligence. However, the transient gas and pressure sensors based on only identical sensing material that concurrently meets the above detection needs have not been reported. Here, we present transient all-MXene NO2 and pressure sensors employing three-dimensional porous crumpled MXene spheres prepared by ultrasonic spray pyrolysis technology as the sensing layer, accompanied with water-soluble polyvinyl alcohol substrates embedded with patterned MXene electrodes. The gas sensor achieves a ppb-level of highly selective NO2 sensing, with a response of up to 12.11% at 5 ppm NO2 and a detection range of 50 ppb-5 ppm, while the pressure sensor has an extremely wide linear pressure detection range of 0.14-22.22 kPa and fast response time of 34 ms. In parallel, all-MXene NO2 and pressure sensors can be rapidly degraded in medical H2O2 within 6 h. This work provides a new avenue toward environmental monitoring, human physiological signal monitoring, and recyclable transient electronics.

14.
JMIR Public Health Surveill ; 8(8): e34150, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35972779

RESUMEN

BACKGROUND: Men who have sex with men (MSM) are at high risk for HIV infection. Accurate estimation of the population size and monitoring the risk sexual behavioral change of MSM is of great importance to develop targeted HIV prevention and interventions. OBJECTIVE: The goal of the research was accurate estimation of the population size and monitoring the risk sexual behavioral change of MSM. METHODS: Street interception investigation methods were conducted among males aged 16 years and older in selected sites in Shenzhen in 2014 and 2019. A population survey was used to estimate the population size of MSM. Logistic regression analysis was applied to evaluate the difference in behavioral characteristics in MSM from 2014 to 2019. RESULTS: In this study, we surveyed 10,170 participants in 2014, of whom 448 (4.41%, 95% CI 4.01%-4.80%) participants were men who have ever had sex with another man (MSMe) and 229 (2.25%, 95% CI 1.96%-2.54%) were men who had sex with another man in the previous 6 months (MSMa). A total of 10,226 participants were surveyed in 2019, of which 500 (4.90%, 95% CI 4.47%-5.31%) and 208 (2.03%, 95% CI 1.76%-2.31%) participants were MSMe and MSMa, respectively. The results showed that the population size of MSM who are active (MSMa) in Shenzhen was 155,469 (2.29%, 95% CI 2.28%-2.30%) in 2014 and 167,337 (2.05%, 95% CI 2.04%-2.06%) in 2019. It was estimated that there were about 12,005,445 (2.04%, 95% CI 2.04%-2.04%) MSMa in China in 2019. Compared with 2014, the MSMa in 2019 were more likely to seek sex partners through mobile phone apps and less likely to have male and female sex partners in addition to having inconsistent condom use and more than 6 sex partners in the previous 6 months. CONCLUSIONS: In Shenzhen, the proportion of MSMa among the general male population was lower in 2019 than in 2014, and the prevalence of HIV risk behavior was reduced in 2019. Although the preferred platform to find male sex partners among MSM has changed, intervention with high-HIV risk MSM could still help to reduce HIV risk behaviors among the whole MSM group. Because MSM prefer to seek sex partners through mobile phone apps, further study is needed to strengthen internet interventions with high-HIV risk MSM to curb the spread of HIV.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Humanos , Estudios Longitudinales , Masculino , Densidad de Población
15.
Heliyon ; 7(11): e08379, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34825088

RESUMEN

Airborne pollen causes various types of allergies in humans, and the extent of allergic infection is related to the presence of different types of sporo-pollen and existing meteorological conditions in a certain area. Therefore, an aeropalynological study of 72 airborne samples with a hydrofluoric acid (HF) treatment was conducted in the Haizhu district of Guangzhou, China, in 2016, to identify the temporal variations in airborne sporo-pollen and the relationship between airborne sporo-pollen concentrations and different meteorological variables in Guangzhou, China. Forty-five types of airborne pollen, seven types of airborne spores, and some undetermined sporo-pollen taxa were identified with two separate plant habitats occurring during this period (from January to December 2016): arboreal pollen (tree-based) and non-arboreal pollen (herb, shrub, aquatic, liane, etc.). Furthermore, the daily records of four key meteorological variables (temperature, precipitation, relative humidity, and wind speed) were acquired to distinguish the pollen seasons and correlated with Spearman's rho test to establish a pollen-weather data book with the seasonal variations. The two leading seasons were identified based on pollen abundance: spring and autumn. Among them, the primary dominant sporo-pollen families during the spring season were Poaceae, Pinaceae, Euphorbiaceae, Moraceae, Microlepia sp., and Polypodiaceae. Conversely, Artemisia sp., Asteraceae, Cyperaceae, Poaceae, Alnus sp., Corylus sp., Myrtaceae, and Rosaceae were the dominant pollen species during autumn. However, few pollen grains were identified in January, May-July, and December. The statistical analysis revealed that temperature had both positive and negative correlations with sporo-pollen concentrations. However, precipitation and relative humidity had a strong impact on the sporo-pollen dispersion and exhibited a negative correlation with the sporo-pollen concentrations. The wind speed had a positive but strong correlation with the sporo-pollen concentration during the study period. Some inconsistent results were found due to environmental variations, vegetation type, and climate change around the study area. This study will facilitate the identification of pollen seasons to prevent the occurrence of pollen-related allergies in the Guangzhou city area.

16.
Adv Healthc Mater ; 10(17): e2100221, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34272931

RESUMEN

Stretchable electronics have advanced rapidly and many applications require high repeatability and robustness under various mechanical deformations. It has been described here that how a highly stretchable and reliable conductor composite made from helical copper wires and a soft elastomer, named eHelix, can provide mechanically robust and strain-insensitive electronic conductivity for wearable devices. The reversibility of the mechanical behavior of the metal-elastomer system has been studied using finite element modeling methods. Optimal design parameters of such helical metal-elastomer structures are found. The scaling of multiple copper wires into such helical shapes to form a Multi-eHelix system is further shown. With the same elastomer volume, Multi-eHelix has more conductive paths and a higher current density than the single-eHelix. Integrations of these eHelix stretchable conductors with fabrics showed wearable displays that can survive machine-washes and hundreds of mechanical loading cycles. The integration of the eHelix developed by us with a wearable optical heart rate sensor enabled a wearable health monitoring system that can display measured heart rates on clothing. Furthermore, Multi-eHelix conductors are used to connect flexible printed circuit boards and piezoresistive sensors on a tactile sensing glove for the emerging sensorized prosthetics.


Asunto(s)
Elastómeros , Dispositivos Electrónicos Vestibles , Conductividad Eléctrica , Frecuencia Cardíaca , Textiles
17.
ACS Sens ; 6(12): 4435-4442, 2021 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-34855360

RESUMEN

Portable and sensitive mixed-potential type solid-state electrolyte (MPSE) gas sensors can detect exhaled biomarkers in a noninvasive and inexpensive way, which is significant for convenient disease diagnosis and saving medical resources. However, high working temperature is still one of the main bottlenecks for hindering MPSE gas sensors' applications in disease diagnosis. Here, we, for the first time, developed and fabricated new room-temperature MPSE gas sensors utilizing K2Fe4O7 electrolyte and Ni/Fe-MOF (Ni/Fe clusters are coordinated with 1,4-H2BDC) sensing electrodes (SEs) for the detection of ppb-level NO. Among different MOF SEs, the sensor attached with the Ni-MOF SE presents the highest NO sensitivities. This is attributed to a reducing oxygen reduction reaction activity and enhancing NO electrochemical catalytic reaction activity, verified by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests. In addition, the presented sensor also shows a low detection limit (20 ppb), fast response/recovery characteristic (17 s/6 s to 50 ppb NO), excellent selectivity, acceptable repeatability, and long-term stability of 34 days to NO at 25 °C and 60%RH. Simultaneously, the mechanism of humidity effect on the sensing performance was investigated by EIS and CV tests. Our work provides new insight into the development of room-temperature solid-state electrolyte gas sensors based on the mixed-potential mechanism and enlarges the potential application domain.


Asunto(s)
Electrólitos , Electrodos , Humedad , Temperatura
18.
Commun Biol ; 3(1): 116, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32170210

RESUMEN

Notch signaling is highly conserved in most animals and plays critical roles during neurogenesis as well as embryonic development. Synthetic Notch-based systems, modeled from Notch receptors, have been developed to sense and respond to a specific extracellular signal. Recent advancement of synNotch has shown promise for future use in cellular engineering to treat cancers. However, synNotch from Morsut et al. (2016) has a high level of ligand-independent activation, which limits its application. Here we show that adding an intracellular hydrophobic sequence (QHGQLWF, named as RAM7) present in native Notch, significantly reduced ligand-independent activation. Our enhanced synthetic Notch receptor (esNotch) demonstrates up to a 14.6-fold reduction in ligand-independent activation, without affecting its antigen-induced activation efficiency. Our work improves a previously reported transmembrane receptor and provides a powerful tool to develop better transmembrane signaling transduction modules for further advancement of eukaryotic synthetic biology.


Asunto(s)
Ingeniería Celular/métodos , Receptores Artificiales/química , Receptores Artificiales/metabolismo , Receptores Notch/química , Receptores Notch/metabolismo , Secuencia de Aminoácidos , Antígenos/metabolismo , Membrana Celular/metabolismo , Clonación Molecular/métodos , Células HEK293 , Humanos , Ligandos , Plásmidos/genética , Dominios Proteicos , Proteolisis , Receptores Notch/genética , Transducción de Señal/genética , Anticuerpos de Cadena Única , Biología Sintética/métodos , Transfección
19.
Proc Inst Mech Eng H ; 234(1): 39-47, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31674876

RESUMEN

This study investigates the effect of dispensing glucose oxidase enzyme onto the reaction zone of a golden electrode via a jetting dispenser. Each droplet of enzyme solution dispensed onto the reaction zone of golden electrode weighs exactly the same at around 0.4 mg. This study shows that the spring and needle assembly can be controlled by adjusting the stroke value of the stroke adjustment knob to generate different jet dispensing effects, thus affecting the change of droplets of glucose oxidase enzyme solution within the reaction zone of the golden electrode. This study performs experiments using three stroke values, which are 0.8, 1.2, and 1.6 mm. The experimental results show that adjusting the stroke value to change the droplet of the dispensing liquid will significantly affect the accuracy of the test strip reading value. When the stroke value is adjusted to 1.5 mm, the standard deviation of the test strip is 3.8 mg/dL and the coefficient of variation is 4.1%-6.1%. The study suggested that adjusting the stroke value can stabilize the dispensed droplet to increase the stability of test strip reading, improving the accuracy of the test strip reading. This adjustment method can also be applied to the process of other biochemical sensors.


Asunto(s)
Técnicas Biosensibles/instrumentación , Glucosa/análisis , Oro/química , Hidrodinámica , Electrodos , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Modelos Lineales
20.
Nat Commun ; 11(1): 5747, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-33184285

RESUMEN

Human skin is a self-healing mechanosensory system that detects various mechanical contact forces efficiently through three-dimensional innervations. Here, we propose a biomimetic artificially innervated foam by embedding three-dimensional electrodes within a new low-modulus self-healing foam material. The foam material is synthesized from a one-step self-foaming process. By tuning the concentration of conductive metal particles in the foam at near-percolation, we demonstrate that it can operate as a piezo-impedance sensor in both piezoresistive and piezocapacitive sensing modes without the need for an encapsulation layer. The sensor is sensitive to an object's contact force directions as well as to human proximity. Moreover, the foam material self-heals autonomously with immediate function restoration despite mechanical damage. It further recovers from mechanical bifurcations with gentle heating (70 °C). We anticipate that this material will be useful as damage robust human-machine interfaces.


Asunto(s)
Biomimética/instrumentación , Técnicas Biosensibles/instrumentación , Impedancia Eléctrica , Técnicas Electroquímicas/instrumentación , Piel , Materiales Biomiméticos , Biomimética/métodos , Técnicas Biosensibles/métodos , Conductividad Eléctrica , Técnicas Electroquímicas/métodos , Electrodos , Diseño de Equipo , Humanos , Fenómenos Mecánicos , Nanoestructuras , Nanotecnología/instrumentación , Nanotecnología/métodos , Piel/lesiones , Propiedades de Superficie , Cicatrización de Heridas
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