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1.
Anal Methods ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842490

RESUMEN

Correction for 'UHPLC-MS/MS combined with microdialysis for simultaneous determination of nicotine and neurotransmitter metabolites in the rat hippocampal brain region: application to pharmacokinetic and pharmacodynamic study' by Mingyu Zhu et al., Anal. Methods, 2024, https://doi.org/10.1039/d4ay00522h.

2.
Inflammation ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717634

RESUMEN

Nicotine, the primary alkaloid in tobacco products, has been shown to have immunoregulatory function in at least 20 diseases. The biological mechanism of action of nicotine immunoregulation is complex, resulting in an improvement of some disease states and exacerbation of others. Given the central role of the NLRP3 inflammasome in macrophages among multiple inflammatory diseases, this study examined how nicotine alters NLRP3 inflammasome activation in macrophages. NLRP3 inflammasome activation was examined mechanistically in the context of different nicotine dosages. We show NLRP3 inflammasome activation, apoptosis-associated speck-like protein (ASC) expression, caspase-1 activity and subsequent IL-1ß secretion were positively correlated with nicotine in a dose-dependent relationship, and destabilization of lysosomes and ROS production were also involved. At high concentrations of nicotine surpassing 0.25 mM, NLRP3 inflammasome activity declined, along with increased expression of the anti-inflammatory Alpha7 nicotinic acetylcholine receptor (α7nAChR) and the inhibition of TLR4/NF-κB signaling. Consequently, high doses of nicotine also reduced ASC expression, caspase-1 activity and IL-1ß secretion in macrophages. Collectively, these results suggest a dual regulatory function of nicotine on NLRP3 inflammasome activation in macrophages, that is involved with the pro-inflammatory effects of lysosomal destabilization and ROS production. We also show nicotine mediates anti-inflammatory effects by activating α7nAChR at high doses.

3.
J Med Internet Res ; 26: e48564, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748460

RESUMEN

BACKGROUND: The information epidemic emerged along with the COVID-19 pandemic. While controlling the spread of COVID-19, the secondary harm of epidemic rumors to social order cannot be ignored. OBJECTIVE: The objective of this paper was to understand the characteristics of rumor dissemination before and after the pandemic and the corresponding rumor management and debunking mechanisms. This study aimed to provide a theoretical basis and effective methods for relevant departments to establish a sound mechanism for managing network rumors related to public health emergencies such as COVID-19. METHODS: This study collected data sets of epidemic rumors before and after the relaxation of the epidemic prevention and control measures, focusing on large-scale network rumors. Starting from 3 dimensions of rumor content construction, rumor propagation, and rumor-refuting response, the epidemic rumors were subdivided into 7 categories, namely, involved subjects, communication content, emotional expression, communication channels, communication forms, rumor-refuting subjects, and verification sources. Based on this framework, content coding and statistical analysis of epidemic rumors were carried out. RESULTS: The study found that the rumor information was primarily directed at a clear target audience. The main themes of rumor dissemination were related to the public's immediate interests in the COVID-19 field, with significant differences in emotional expression and mostly negative emotions. Rumors mostly spread through social media interactions, community dissemination, and circle dissemination, with text content as the main form, but they lack factual evidence. The preferences of debunking subjects showed differences, and the frequent occurrence of rumors reflected the unsmooth channels of debunking. The χ2 test of data before and after the pandemic showed that the P value was less than .05, indicating that the difference in rumor content before and after the pandemic had statistical significance. CONCLUSIONS: This study's results showed that the themes of rumors during the pandemic are closely related to the immediate interests of the public, and the emotions of the public accelerate the spread of these rumors, which are mostly disseminated through social networks. Therefore, to more effectively prevent and control the spread of rumors during the pandemic and to enhance the capability to respond to public health crises, relevant authorities should strengthen communication with the public, conduct emotional risk assessments, and establish a joint mechanism for debunking rumors.


Asunto(s)
COVID-19 , Difusión de la Información , Pandemias , COVID-19/prevención & control , COVID-19/epidemiología , Humanos , China/epidemiología , Difusión de la Información/métodos , Pandemias/prevención & control , SARS-CoV-2 , Medios de Comunicación Sociales/estadística & datos numéricos , Comunicación
4.
Anal Methods ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738307

RESUMEN

Nicotine crosses the blood-brain barrier and interacts with nicotinic acetylcholine receptors, initiating a cascade of neurotransmitter effects with potential therapeutic implications for neurodegenerative conditions such as Alzheimer's and Parkinson's disease. The hippocampus, pivotal for cognitive processes, plays a crucial role in nicotine-mediated cognitive enhancement due to its abundant expression of nicotinic acetylcholine receptors, particularly the α7 subtype, which is heavily implicated in hippocampus-related behavioral functions and dysfunctions. However, the intricate process of nicotine metabolism within the hippocampus remains poorly understood, impeding our comprehension of how nicotine and its metabolites modulate neurotransmitter dynamics. To address this gap, we have developed and validated a novel methodology combining microdialysis with UHPLC-MS/MS, enabling simultaneous detection of 12 neurotransmitters, nicotine, and its seven metabolites within the rat hippocampus. The linearity range of the targeted compounds is satisfactory (R2 > 0.9970), with intra-day and inter-day precision not exceeding 12.7%, and accuracy ranging from -12.4% to 13.7%. Our findings reveal differential pharmacokinetics of nicotine and its metabolites in the α7KO group compared to the control group, characterized by heightened nicotine absorption and slower elimination and distribution in the former. Notably, the pharmacokinetic parameters of cotinine exhibit similarity across both groups. Studies investigating the impact of nicotine on monoamine neurotransmitters have elucidated its capacity to augment the release of dopamine, serotonin, norepinephrine, glutamate, and acetylcholine in the rat hippocampus. This integrated approach facilitates a comprehensive analysis of neurotransmitter alterations within the hippocampal region following nicotine administration, thereby providing robust technical support and scientific rationale for understanding the neurochemical effects of nicotine and its metabolites. Further exploration into the pharmacokinetics and pharmacodynamics of nicotine holds promise for uncovering novel therapeutic avenues in the management of neurodegenerative diseases such as Alzheimer's.

5.
Genes (Basel) ; 15(4)2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38674424

RESUMEN

Since the MerR family is known for its special regulatory mechanism, we aimed to explore which factors determine the expression activity of the mer promoter. The Tn501/Tn21 mer promoter contains an abnormally long spacer (19 bp) between the -35 and -10 elements, which is essential for the unique DNA distortion mechanism. To further understand the role of base sequences in the mer promoter spacer, this study systematically engineered a series of mutant derivatives and used luminescent and fluorescent reporter genes to investigate the expression activity of these derivatives. The results reveal that the expression activity of the mer promoter is synergistically modulated by the spacer length (17 bp is optimal) and the region upstream of -10 (especially -13G). The spacing is regulated by MerR transcription factors through symmetrical sequences, and -13G presumably functions through interaction with the RNA polymerase sigma-70 subunit.


Asunto(s)
Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Regiones Promotoras Genéticas , Pseudomonas aeruginosa , Factor sigma , Pseudomonas aeruginosa/genética , Proteínas Bacterianas/genética , Factor sigma/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Elementos Transponibles de ADN/genética
6.
Cell Rep ; 43(3): 113959, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38483903

RESUMEN

The extrinsic diet and the intrinsic developmental programs are intertwined. Although extensive research has been conducted on how nutrition regulates development, whether and how developmental programs control the timing of nutritional responses remain barely known. Here, we report that a developmental timing regulator, BLMP-1/BLIMP1, governs the temporal response to dietary restriction (DR). At the end of larval development, BLMP-1 is induced and interacts with DR-activated PHA-4/FOXA, a key transcription factor responding to the reduced nutrition. By integrating temporal and nutritional signaling, the DR response regulates many development-related genes, including gska-3/GSK3ß, through BLMP-1-PHA-4 at the onset of adulthood. Upon DR, a precocious activation of BLMP-1 in early larval stages impairs neuronal development through gska-3, whereas the increase of gska-3 by BLMP-1-PHA-4 at the last larval stage suppresses WNT signaling in adulthood for DR-induced longevity. Our findings reveal a temporal checkpoint of the DR response that protects larval development and promotes adult health.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Restricción Calórica , Regulación de la Expresión Génica , Longevidad/genética , Factores de Transcripción/metabolismo , Vía de Señalización Wnt
7.
Front Public Health ; 12: 1258188, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38444439

RESUMEN

Introduction: In the response to and prevention and control of the Novel coronavirus pneumonia, the COVID-19 vaccine does not provide lifelong immunity, and it is therefore important to increase the rate of booster shots of the COVID-19 vaccine. In the field of information health science, research has found that information frames have an impact in changing individual attitudes and health behaviors. Objective: This study focuses on the effects of different influencing factors on the public's willingness to receive the booster shots of the COVID-19 vaccine under two information frameworks. Methods: An online questionnaire was conducted to explore the effects of demographic characteristics, personal awareness, social relationships, risk disclosure, perceived booster vaccination protection rate, and duration of protection under the assumption of an information framework. T test and one-way analysis were used to testing the effect of variables. Results: (1) The persuasion effect under the gain frame is higher than that under the loss frame (B = 0.863 vs. B = 0.746); (2) There was no significant difference in subjects' intention of booster vaccination in terms of gender, age, income, occupation, educational background and place of residence. Whether family members received booster vaccination was strongly correlated with their intention of vaccination under the loss framework (p = 0.017, M = 4.63, SD = 0.664). (3) The higher the understanding of COVID-19, the higher the degree of compliance with the government's COVID-19 prevention and control measures, and the higher the willingness to strengthen vaccination; (4) Risk disclosure has a significant impact on people's willingness to receive COVID-19 booster shots (M = 2.48, under the loss framework; M = 2.44, under the gain framework); (5) Vaccine protection rate and duration of protection have an impact on people's willingness to vaccinate. Increased willingness to vaccinate when the protection rate of booster vaccine approaches 90% (M = 4.76, under the loss framework; M = 4.68, under the gain framework). When the vaccine protection period is 2 years, people are more willing to receive a booster vaccine; and the willingness to receive a booster shot is stronger under the loss framework (M = 4.60, SD = 0.721, p = 0.879). Conclusion: The impact of the information framework on COVID-19 vaccination intentions is different, and the disclosure of relevant health information should focus on the impact of the information framework and content on the public's behavior toward strengthening vaccination. Therefore, in the face of public health emergencies, public health departments, healthcare institutions, and other sectors can consider adopting the Gainful Information Framework tool to disseminate health information to achieve better persuasion and promote public health behavior change enhancing public health awareness, and promoting universal vaccination.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Intención , COVID-19/prevención & control , Vacunación , China
8.
Mol Neurobiol ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38427211

RESUMEN

The exact relationship between nicotine metabolism and dependence is not fully understood but is known to be influenced at a molecular level by genetic factors. A sample comprising 274 Chinese adult male smokers was categorized into groups based on their metabolic rates, namely fast, intermediate, and slow metabolizers. We then measured their smoking topography, evaluated their nicotine dependence, and assessed the rewarding effects. Based on these findings, we proposed the hypothesis that the rate of nicotine metabolism could influence the level of dopamine release which in turn had repercussions on the pleasurable and rewarding effects. To test this hypothesis, male mice were selected with different nicotine metabolic rates that closely resembled in the smoker group. We evaluated their nicotine dependence and rewarding effects through conditioned place preference and withdrawal symptom tests, supplemented with dopamine release measurements. In both animal and human, the slow metabolism group (SMG) required less nicotine to maintain a comparable level of dependence than the fast metabolism group (FMG). The SMG could achieve similar rewarding effects to FMG despite consuming less nicotine. Comparable dopamine levels released were therefore critical in setting the nicotine acquisition behavior in this animal model and also for the smokers tested. Our findings suggested that even within the same ethnicity of established smokers (Chinese Han), differences in nicotine metabolism were an important parameter to modulate the degree of nicotine dependence.

9.
Chemphyschem ; 25(8): e202300897, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38323673

RESUMEN

As a photocathode with a band gap of about 1.8 eV, copper bismuthate (CuBi2O4) is a promising material for photoelectrochemical (PEC) water splitting. However, weak charge transfer capability and severe carrier recombination suppress the PEC performance of CuBi2O4. In this paper, the conductivity and carriers transport of CuBi2O4 are improved via introducing Zn2+ into the synthesis precursor of CuBi2O4, driving a beneficial 110 mV positive shift of onset potential in photocurrent. Detailed investigations demonstrate that the introduction of an appropriate amount of zinc leads to in situ segregation of ZnO which serves as an electron transport channel on the surface of CuBi2O4, forming heterojunctions. The synergistic effect of heterojunctions and doping simultaneously promotes the charge transfer and the carrier concentration. OCP experiment proves that ZnO/Zn-CuBi2O4 possesses better charge separation; the Mott-Schottky curve shows that the doping of Zn significantly enhances the carrier concentration; carrier lifetime calculated from time-resolved photoluminescence confirms faster extraction of carriers.

10.
Food Chem Toxicol ; 185: 114431, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38176581

RESUMEN

Humans are usually exposed to nicotine through the use of tobacco products. Although it is generally believed that nicotine is relatively harmless in tobacco consumption, it is, in fact, a toxic substance that warrants careful consideration of its potential toxicity. However, the current understanding of the neurotoxicity of nicotine is still very limited. In this study, we aim to reveal the toxic risk of nicotine to key target neuronal cells and its potential toxic mechanisms. The results showed that nicotine induced cell death, ROS increase, mitochondrial membrane potential decrease, and DNA damage in SH-SY5Y human neuroblastoma cells at millimolar concentrations, but did not cause toxic effects at the physiological concentration. These toxic effects were accompanied by cytoplasmic vacuolation. The inhibition of cytoplasmic vacuolation by bafilomycin A1 greatly reduced nicotine-induced cell death, indicating that cytoplasmic vacuolation is the key driving factor of cell death. These cytoplasmic vacuoles originated from the trans-Golgi network (TGN) and expressed microtubule-associated protein 1 light chain 3-II (LC3-II) and lysosomal associated membrane protein 1(LAMP1). The presence of LC3-II and LAMP1 within these vacuoles serves as evidence of compromised TGN structure and function. These findings provide valuable new insights into the potential neurotoxic risk and mechanisms of nicotine.


Asunto(s)
Neuroblastoma , Nicotina , Humanos , Nicotina/toxicidad , Línea Celular Tumoral , Red trans-Golgi , Muerte Celular
11.
Toxicol Res (Camb) ; 12(5): 902-912, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37915495

RESUMEN

Background: Researches have shown that chronic inhalation of cigarette smoke (CS) disrupts male reproductive system, but it is unclear about the mechanisms behind reproductive damages by tobacco toxicants in male rats. This study was designed to explore the effects of heated tobacco products (HTP) aerosols and CS exposure on the testicular health of rats. Materials and Methods: Experiments were performed on male SD rats exposed to filtered air, HTP aerosols at 10 µg/L, 23 µg/L, and 50 µg/L nicotine-equivalent contents, and also CS at 23 µg/L nicotine-equivalent content for 90 days in five exposure groups (coded as sham, HTP_10, HTP_23, HTP_50 and Cig_23). The expression of serum testosterone, testicular tissue inflammatory cytokines (IL-1ß, IL-6, IL-10, TNF-α), reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA), NLRP3 inflammasome-related mRNAs and proteins (NLRP3, ASC, and Caspase-1), the degree of pyroptosis and histopathology were investigated. Results: The results demonstrated that HTP_50 and Cig_23 caused varying degrees of oxidative damage to rat testis, resulting in a decrease of sperm quantity and serum testosterone contents, an increase in the deformity rate, expression levels of proinflammatory cytokines, and NLRP3 inflammasome-related mRNA, and an increase in the NLRP3, ASC, and Caspase-1-immunopositive cells, pyroptosis cell indices, and histopathological damage in the testes of rats. Responses from the HTP_10 and HTP_23 groups were less than those found in the above two exposure groups. Conclusion: These findings indicate that HTP_50 and Cig_23 induced oxidative stress in rat testes, induced inflammation and pyroptosis through the ROS/NLRP3/Caspase-1 pathway, and destroyed the integrity of thetesticular tissue structure.

12.
Front Neurosci ; 17: 1288102, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38033549

RESUMEN

Since their introduction in the United States and Europe in 2007, electronic cigarettes (E-Cigs) have become increasingly popular among smokers. Nicotine, a key component in both tobacco and e-cigarettes, can exist in two forms: nicotine-freebase (FBN) and nicotine salts (NS). While nicotine salt is becoming more popular in e-cigarettes, the effect of nicotine salts on reinforcement-related behaviors remains poorly understood. This study aimed to compare the reinforcing effects of nicotine and nicotine salts in animal models of drug self-administration and explore potential mechanisms that may contribute to these differences. The results demonstrated that three nicotine salts (nicotine benzoate, nicotine lactate, and nicotine tartrate) resulted in greater reinforcement-related behaviors in rats compared to nicotine-freebase. Moreover, withdrawal-induced anxiety symptoms were lower in the three nicotine salt groups than in the nicotine-freebase group. The study suggested that differences in the pharmacokinetics of nicotine-freebase and nicotine salts in vivo may explain the observed behavioral differences. Overall, this study provides valuable insights into the reinforcing effects of nicotine as well as potential differences between nicotine-freebase and nicotine salts.

13.
ACS Appl Mater Interfaces ; 15(43): 50265-50274, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37871267

RESUMEN

The electrostrictive effect, which induces strain in ferroelectric ceramics, offers distinct advantages over its piezoelectric counterpart for high-precision actuator applications, including anhysteretic behavior even at high frequencies, rapid reaction times, and no requirement for poling. Historically, commercially available electrostrictive materials have been lead oxide-based. However, global restrictions on the use of lead in electronic components necessitate the exploration of lead-free electrostrictive ceramics with a high strain performance. Although various engineering strategies for producing materials with high strain have been proposed, they typically come at the expense of increased strain hysteresis. Here, we describe the extraordinary electrostrictive response of (Ba0.95Ca0.05)(Ti0.88Sn0.12)O3 (BCTS) ceramics with ultrahigh electrostrictive strain and negligible hysteresis achieved through texture engineering leveraging the anisotropic intrinsic lattice contribution. The BCTS ceramics exhibit a high unipolar strain of 0.175%, a substantial electrostrictive coefficient Q33 of 0.0715 m4 C-2, and an ultralow hysteresis of less than 0.8%. Notably, the Q33 value is three times greater than that of high-performance lead-based Pb(Mg1/3Nb2/3)O3 electrostrictive ceramics. Multiscale structural analyses demonstrate that the electrostrictive effect dominates the BCTS strain response. This research introduces a novel approach to texture engineering to enhance the electrostrictive effect, offering a promising paradigm for future advancements in this field.

14.
Anal Bioanal Chem ; 415(27): 6771-6783, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37776352

RESUMEN

Phosphatidylcholine (PC) and lysophosphatidylcholine (LPC), two types of phospholipids (PLs), have been reported to be closely correlated with head and neck cancers of laryngeal cancer (LC) and thyroid cancer (TC), which make their analysis crucial. TiO2@COF-based solid-phase microextraction (SPME) coupled to UHPLC-MS/MS was developed for the rapid and accurate detection of seven potential PL biomarkers from small amounts of serum in this work. The combination of TiO2 and COF proves to be effective for the extraction of the target analytes. Under optimal conditions, the developed TiO2@COF-based SPME-UHPLC-MS/MS method revealed good linearity (R2 ≥ 0.997) with LODs ranging from 0.05 to 0.38 ng/mL for PLs, the extraction recoveries and matrix effects ranging from 83.09-112.03% and 85.38-113.67%, respectively. As a high-throughput pretreatment method, satisfactory probe-to-probe reproducibility rates of 2.7-10.1% were obtained. Finally, the TiO2@COF-based SPME-UHPLC-MS/MS method was applied to analyze LPC 14:0, LPC 16:0, LPC 18:0, LPC 18:1, LPC 19:0, PC 16:0/18:1, and PC 18:0 in serum samples from early LC patients (n = 15), early TC patients (n = 15), and healthy volunteers (n = 15). The results indicated that cancer patients could be effectively differentiated from healthy controls using orthogonal partial least squares discriminant analysis (OPLS-DA). In conclusion, the established TiO2@COF-based SPME-UHPLC-MS/MS method is reliable for the rapid determination of the seven PLs in serum samples, which is promising for early diagnosis of head and neck cancers.

15.
Environ Sci Technol ; 57(40): 15255-15265, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37768274

RESUMEN

Numerous studies have emphasized the toxicity of graphene-based nanomaterials to algae, however, the fundamental behavior and processes of graphene in biological hosts, including its transportation, metabolization, and bioavailability, are still not well understood. As photosynthetic organisms, algae are key contributors to carbon fixation and may play an important role in the fate of graphene. This study investigated the biological fate of 14C-labeled few-layer graphene (14C-FLG) in Chlamydomonas reinhardtii (C. reinhardtii). The results showed that 14C-FLG was taken up by C. reinhardtii and then translocated into its chloroplast. Metabolomic analysis revealed that 14C-FLG altered the metabolic profiles (including sugar metabolism, fatty acid, and tricarboxylic acid cycle) of C. reinhardtii, which promoted the photosynthesis of C. reinhardtii and then enhanced their growth. More importantly, the internalized 14C-FLG was metabolized into 14CO2, which was then used to participate in the metabolic processes required for life. Approximately 61.63%, 25.31%, and 13.06% of the total radioactivity (from 14CO2) was detected in carbohydrates, lipids, and proteins of algae, respectively. Overall, these results reveal the role of algae in the fate of graphene and highlight the potential of available graphene in bringing biological effects to algae, which helps to better assess the environmental risks of graphene.

16.
Food Chem X ; 18: 100716, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37397212

RESUMEN

Tobacco is a widely cultivated cash crop, but it is often smuggled and sold illegally. Unfortunately, there is currently no way to verify the origin of tobacco in China. In an effort to address this issue, we conducted a study using stable isotopes and elements from 176 tobacco samples at both provincial and municipal scales. Our findings revealed significant differences in δ13C, K, Cs, and 208/206Pb at the provincial-level, and Sr, Se, and Pb at the municipal level. We created a heat map at the municipal level, which showed a similar cluster classification to geographic grouping and provided an initial assessment of tobacco origins. Using OPLS-DA modeling, we achieved a 98.3% accuracy rate for the provincial scale and 97.6% for the municipal scale. It is worth noting that the importance of rankings of variables varied depending on the spatial scale of the evaluation. This study offers the first traceability fingerprint dataset of tobacco and has the potential to combat mislabeling and fraudulent conduct by identifying the geographical origin of tobacco.

17.
Sensors (Basel) ; 23(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37447900

RESUMEN

Accurate detection and timely treatment of component defects in substations is an important measure to ensure the safe operation of power systems. In this study, taking substation meters as an example, a dataset of common meter defects, such as a fuzzy or damaged dial on the meter and broken meter housing, is constructed from the images of manual inspection in power systems. There are several challenges involved in accurately detecting defects in substation meter images, such as the complex background, different meter sizes and large differences in the shapes of meter defects. Therefore, this paper proposes the PHAM-YOLO (Parallel Hybrid Attention Mechanism You Only Look Once) network for automatic detection of substation meter defects. In order to make the network pay attention to the key areas against the complex background of the meter defect images and the differences between different defect features, a Parallel Hybrid Attention Mechanism (PHAM) module is designed and added to the backbone of YOLOv5. PHAM integration of local and non-local correlation information can highlight these differences while remaining focused on the meter defect features. To improve the expressive ability of the feature map, a Spatial Pyramid Pooling Fast (SPPF) module is introduced, which pools the input feature map using a continuous fixed convolution kernel, fusing the feature maps of different receptive fields. Bounding box regression (BBR) is the key way to determine object positioning performance in defect detection. EIOU (Efficient Intersection over Union) is, therefore, introduced as a boundary loss function to solve the ambiguity of the CIOU (Complete Intersection Over Union) loss function, making the BBR regression more accurate. The experimental results show that the Average Precision Mean (mAP), Precision (P) and Recall (R) of the proposed PHAM-YOLO network in the dataset are 78.3%, 78.3%, and 79.9%, respectively, with mAP being improved by 2.7% compared to the original model and higher than SSD, Fast R-CNN, etc.


Asunto(s)
Algoritmos , Registros , Columna Vertebral
18.
Environ Sci Pollut Res Int ; 30(32): 79423-79436, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37284951

RESUMEN

Long-term use of alcohol and cigarettes is associated with millions of deaths each year, directly or indirectly. The carcinogen acetaldehyde is both a metabolite of alcohol and the most abundant carbonyl compound in cigarette smoke, and co-exposure of them is usual and primarily leads to liver and lung injury, respectively. However, few studies have explored the synchronic risk of acetaldehyde on the liver and lung. Here, we investigated the toxic effects and related mechanisms of acetaldehyde based on normal hepatocytes and lung cells. The results showed that acetaldehyde caused significant dose-dependent increases of cytotoxicity, ROS level, DNA adduct level, DNA single/double-strand breakage, and chromosomal damage in BEAS-2B cells and HHSteCs, with similar effects at the same doses. The gene and protein expression and phosphorylation of p38MAPK, ERK, PI3K, and AKT, key proteins of MAPK/ERK and PI3K/AKT pathways regulating cell survival and tumorigenesis, were significantly upregulated on BEAS-2B cells, while only protein expression and phosphorylation of ERK were upregulated significantly, the other three decreased in HHSteCs. When either the inhibitor of the four key proteins was co-treated with acetaldehyde, cell viabilities were almost unchanged in BEAS-2B cells and HHSteCs. Thus, acetaldehyde could synchronically induce similar toxic effects in BEAS-2B cells and HHSteCs, and MAPK/ERK and PI3K/AKT pathways seem to be involved in different regulatory mechanisms.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Acetaldehído/toxicidad , Línea Celular , Daño del ADN
19.
Dalton Trans ; 52(22): 7544-7550, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37183969

RESUMEN

BiVO4 possesses a suitable band gap for photoelectrochemical (PEC) water splitting to produce hydrogen; however, the performance of BiVO4 is limited by several adverse factors. The bulk charge recombination and the slow surface water oxidation reaction of BiVO4 are main unfavorable factors. In view of these disadvantages, an Fe-Bi electrocatalyst is loaded on BiVO4 to improve the PEC performance of BiVO4. After modification, the onset potential of BiVO4 shifts negatively by 60 mV, and the saturated photocurrent is greatly increased. Systematic studies demonstrate that the Fe-Bi electrocatalyst not only enhances the bulk charge separation, but also accelerates the surface water oxidation rate of BiVO4 and greatly reduces the resistance of the reaction interface.

20.
Research (Wash D C) ; 6: 0087, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36951803

RESUMEN

The study of lipid metabolism relies on the characterization of the lipidome, which is quite complex due to the structure variations of the lipid species. New analytical tools have been developed recently for characterizing fine structures of lipids, with C=C location identification as one of the major improvements. In this study, we studied the lipid metabolism reprograming by analyzing glycerol phospholipid compositions in breast cancer cell lines with structural specification extended to the C=C location level. Inhibition of the lipid desaturase, stearoyl-CoA desaturase 1, increased the proportion of n-10 isomers that are produced via an alternative fatty acid desaturase 2 pathway. However, there were different variations of the ratio of n-9/n-7 isomers in C18:1-containing glycerol phospholipids after stearoyl-CoA desaturase 1 inhibition, showing increased tendency in MCF-7 cells, MDA-MB-468 cells, and BT-474 cells, but decreased tendency in MDA-MB-231 cells. No consistent change of the ratio of n-9/n-7 isomers was observed in SK-BR-3 cells. This type of heterogeneity in reprogrammed lipid metabolism can be rationalized by considering both lipid desaturation and fatty acid oxidation, highlighting the critical roles of comprehensive lipid analysis in both fundamental and biomedical applications.

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