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1.
Environ Sci Technol ; 58(17): 7433-7444, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38629952

RESUMO

Ozone (O3) profiles are crucial for comprehending the intricate interplay among O3 sources, sinks, and transport. However, conventional O3 monitoring approaches often suffer from limitations such as low spatiotemporal resolution, high cost, and cumbersome procedures. Here, we propose a novel approach that combines multiaxis differential optical absorption spectroscopy (MAX-DOAS) and machine learning (ML) technology. This approach allows the retrieval of O3 profiles with exceptionally high temporal resolution at the minute level and vertical resolution reaching the hundred-meter scale. The ML models are trained using parameters obtained from radiative transfer modeling, MAX-DOAS observations, and a reanalysis data set. To enhance the accuracy of retrieving the aqueous phosphorus from O3, we employ a stacking approach in constructing ML models. The retrieved MAX-DOAS O3 profiles are compared to data from an in situ instrument, lidar, and satellite observation, demonstrating a high level of consistency. The total error of this approach is estimated to be within 25%. On balance, this study is the first ground-based passive remote sensing of high time-height-resolved O3 distribution from ground to the stratopause (0-60 km). It opens up new avenues for enhancing our understanding of the dynamics of O3 in atmospheric environments. Moreover, the cost-effective and portable MAX-DOAS combined with this versatile profiling approach enables the potential for stereoscopic observations of various trace gases across multiple platforms.


Assuntos
Aprendizado de Máquina , Ozônio , Monitoramento Ambiental/métodos
2.
J Environ Sci (China) ; 142: 142-154, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38527880

RESUMO

Formaldehyde (HCHO) is considered one of the most abundant gas-phase carbonyl compounds in the atmosphere, which can be directly emitted through transportation sources. Long-Path Differential Optical Absorption Spectroscopy (LP-DOAS) was used to observe HCHO in the river channel of Wusong Wharf in Shanghai, China for the whole year of 2019. Due to the impact of ship activity, the annual average HCHO level in the channel is about 2.5 times higher than that in the nearby campus environment. To explain the sources of HCHO under different meteorological conditions, the tracer-pair of CO and Ox (NO2+O3) was used on the clustered air masses. The results of the source appointment show that primary, secondary and background account for 24.14% (3.34 ± 1.19 ppbv), 44.78% (6.20 ± 2.04 ppbv) and 31.09% (4.31 ± 2.33 ppbv) of the HCHO in the channel when the air masses were from the mixed direction of the city and channel, respectively. By performing background station subtraction at times of high primary HCHO values and resolving the plume peaks, directly emitted HCHO/NO2 in the channel environment and plume were determined to be mainly distributed between 0.2 and 0.3. General cargo ships with higher sailing speeds or main engine powers tend to have higher HCHO/NO2 levels. With the knowledge of NO2 (or NOx) emission levels from ships, this study may provide data support for the establishment of HCHO emission factors.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Navios , Dióxido de Nitrogênio/análise , China , Monitoramento Ambiental/métodos , Formaldeído/análise
3.
Mol Pharm ; 20(3): 1750-1757, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36668905

RESUMO

Coronavirus disease 2019 (COVID-19) is a serious threat to public health and is in urgent need of specific drugs. Meplazumab, a humanized monoclonal antibody targeting CD147, was confirmed to competitively block the binding between the spike of syndrome coronavirus 2 (SARS-CoV-2) and CD147, making meplazumab a promising candidate drug for COVID-19. In this study, biodistribution and dosimetry of 131I-labeled meplazumab were performed to further evaluate its potential as a therapeutic drug for COVID-19. 131I-meplazumab was both safe and tolerant in mice and healthy volunteers. A biodistribution study was performed in normal mice, and blood samples were used for pharmacokinetic analysis. Three healthy volunteers were included and subjected to single-photon-emission computed tomography (SPECT) imaging of 131I-meplazumab within 2 weeks. The distribution in mice and humans was consistent with the in vivo distribution of CD147. Biodistribution and SPECT imaging results exhibited that the liver was the organ with the highest uptake for both mice and humans. Deiodination of 131I-meplazumab can be observed in vivo, and taking Lugol's solution can protect the thyroid gland effectively. The pharmacokinetic characteristics of 131I-meplazumab in mice and humans best fit the two-compartment model. The clearance half-life (T1/2ß) in mice and humans was 117.4 and 223.5 h, respectively. The results indicated that its pharmacokinetic properties in vivo were ideal. The effective dose calculated from healthy volunteers was 0.811 ± 0.260 mSv·MBq-1, which was twice the value calculated from mice. It was safe and feasible to perform human clinical imaging experiments using a diagnostic dose of 131I-meplazumab after thyroid closure by Lugol's solution. This study will provide more experimental basis for advancing the clinical translation of meplazumab and will be valuable in evaluating therapeutic interventions for patients with COVID-19, as well as providing a reference for clinical translation studies of other antibody drugs.


Assuntos
COVID-19 , Humanos , Animais , Camundongos , Distribuição Tecidual , SARS-CoV-2 , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Radiometria
4.
Environ Sci Technol ; 57(14): 5739-5750, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36989422

RESUMO

We have been effectively protected by disposable propylene face masks during the COVID-19 pandemic; however, they may pose health risks due to the release of fine particles and chemicals. We measured micro/nanoparticles and organic chemicals in disposable medical masks, surgical masks, and (K)N95 respirators. In the breathing-simulation experiment, no notable differences were found in the total number of particles among mask types or between breathing intensities. However, when considering subranges, <2.5 µm particles accounted for ∼90% of the total number of micro/nanoparticles. GC-HRMS-based suspect screening tentatively revealed 79 (semi)volatile organic compounds in masks, with 18 being detected in ≥80% of samples and 44 in ≤20% of samples. Three synthetic phenolic antioxidants were quantified, and AO168 reached a median concentration of 2968 ng/g. By screening particles collected from bulk mask fabrics, we detected 18 chemicals, including four commonly detected in masks, suggesting chemical partition between the particles and the fabric fibers and chemical exposure via particle inhalation. These particles and chemicals are believed to originate from raw materials, intentionally and nonintentionally added substances in mask production, and their transformation products. This study highlights the need to study the long-term health risks associated with mask wearing and raises concerns over mask quality control.


Assuntos
COVID-19 , Nanopartículas , Humanos , COVID-19/prevenção & controle , Máscaras , Polipropilenos , Pandemias/prevenção & controle
5.
Zhongguo Zhong Yao Za Zhi ; 48(15): 4087-4096, 2023 Aug.
Artigo em Zh | MEDLINE | ID: mdl-37802776

RESUMO

To understand the current quality status and rearing situation of Bombyx Batryticatus, the authors collected 102 batches of Bombyx Batryticatus from different main producing areas and five major Chinese medicine markets from 2016 to 2018, and measured the properties and quality of the silk gland, to clarify the quality status of Bombyx Batryticatus from different producing areas and markets. In addition, 35 batches of Bombyx Batryticatus from 2019 to 2022 were used to verify the silk gland after revision. Moreover, Beauveria Bassiana was inoculated in the silkworm of 4-5 instars, and standardized rearing was carried out until they die. The death rate and the quality of Bombyx Batryticatus were measured to determine the differences in Bombyx Batryticatus of different instars, and explore the rationality of the infection age of Bombyx Batryticatus in Chinese Pharmacopoeia(2020). The results revealed that in the 102 batches of Bombyx Batryticatus, the qualification rate of silk gland was low; the content of total ash far exceeded the standard; the content of beauvericin varied greatly. The qualification rate of the silk gland of the 35 batches of Bombyx Batryticatus was only 47.49%, which could be increased to 73.00% if the number of silk gland was 2 to 4. The death rate of Bombyx Batryticatus at different infection ages was quite different, with uneven quality. Generally, the yield of Bombyx Batryticatus inoculated on the first day of the fifth instar was high with good quality. Therefore, in combination with the quality and actual production of Bombyx Batryticatus, the following suggestions were proposed for revision of Bombyx Batryticatus in Chinese Pharmacopoeia(2025): The number of silk gland should be revised as 2-4 bright brown or bright black silk glands, after which, the quality of Bombyx Batryticatus could be guaranteed, and the "quality identification based on character" could also be reflected scientifically; the content determination index that the content of beauvericin shall not be less than 0.017% should be added to better control the quality of Bombyx Batryticatus; the infection age should be revised as the first day of the fifth instar to narrow the age span, which could better fit the actual production and ensure the quality of Bombyx Batryticatus.


Assuntos
Bombyx , Medicina Tradicional do Leste Asiático , Animais , Seda , Larva
6.
Cancer Sci ; 112(9): 3455-3468, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34159686

RESUMO

Clinical reports indicate that gastric cancer (GC) has a high mortality rate, but its pathological mechanism remains poorly understood. This work integrated bioinformatics analysis with experimental verification to explore novel biomarkers of gastric cancer. First, weighted gene coexpression network analysis was applied to screen significant genes correlated with GC development. Gene set enrichment analysis was also used to unearth the most relevant biological functions of significant genes. As a result, we discovered homeobox C9 (HOXC9) as a novel oncogene in GC, primarily through negatively regulating immune response. High expression of HOXC9 predicted a poor prognosis in GC patients, and knocking down HOXC9 efficiently enhanced the interferon-gamma (IFNγ)-dependent apoptosis in two GC cell lines as well as organoids from patients. Furthermore, cleaved caspase-3/7 and phosphorylated signal transducer and activator of transcription 1 (p-STAT1) were also significantly enhanced in HOXC9 knockdown cells and organoids treated with IFNγ. Mechanistically, we found that HOXC9 inhibited the death-associated protein kinase 1 (DAPK1) and its downstream retinoic acid-inducible gene-I (RIG1) to generate GC IFNγ resistance. In summary, we identified and confirmed that HOXC9 generates IFNγ resistance in GC by inhibiting the DAPK1/RIG1/p-STAT1 axis.


Assuntos
Proteínas Quinases Associadas com Morte Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Homeodomínio/metabolismo , Interferon gama/farmacologia , Receptores do Ácido Retinoico/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/genética , Neoplasias Gástricas/metabolismo , Regulação para Cima/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Estudos de Coortes , Bases de Dados Genéticas , Proteínas Quinases Associadas com Morte Celular/genética , Técnicas de Silenciamento de Genes , Proteínas de Homeodomínio/genética , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Oncogenes , Receptores do Ácido Retinoico/genética , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo , Neoplasias Gástricas/patologia , Transfecção
7.
Bioconjug Chem ; 32(9): 2108-2116, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34486879

RESUMO

The kidney is the main dose-limiting organ in radioligand therapy (RLT), and there is an urgent need for reducing renal radioactivity accumulation. According to the enzymolysis clearance strategy, the first objective of this study is to test whether enzymolysis efficiency can be improved by introducing a hydrophobic amino acid with a bulkier side chain to the second position of the cleavable sequence, and the second objective is to screen an optimal sequence to minimize the renal uptake. Four exendin 4 (Ex4) peptide analogues with different cleavable sequences were synthesized and labeled with 68Ga. Both in vitro and in vivo metabolism studies were performed using either the model compounds or the complete probes. The in vitro stabilities of the tracers were evaluated in PBS and mouse serum. The microPET images were acquired in the INS-1 tumor model at different time points, and the radioactivity uptakes of the probes in tumors and kidneys were determined and compared. All the probes were stable in both PBS and mouse serum for at least 1 h. The in vitro cleavage study for both model compounds and intact probes showed enzymolysis efficiency in the following order: MWK > MFK > MVK > MGK. The in vivo metabolism study confirmed that a fragment of 68Ga-NOTA-Met-OH appeared in both kidney and urine samples for all analogues with MVK, MFK, and MWK sequences. The microPET images showed that the tumor uptakes of all the modified probes were comparable to those of the control, while the kidney uptakes were significantly reduced by inserting the MWK, MFK, or MVK linker. The tumor-to-kidney ratios at 0.5, 1, and 2 h time points showed the following order: 68Ga-NOTA-MWK-Ex4 > 68Ga-NOTA-MFK-Ex4 > 68Ga-NOTA-MVK-Ex4. In this study, based on the enzymolysis clearance strategy and the preference of the enzyme, different sequences were designed and compared both in vitro and in vivo. The results indicated that the larger the steric hindrance of the second hydrophobic amino acid side chain, the more effective the enzymatic hydrolysis, with enzymolysis efficiency in the following order: MWK > MFK > MVK > MGK. MWK appears to be the most effective sequence in reducing renal radioactivity accumulation of exendin 4 peptide derivatives.


Assuntos
Radioisótopos de Gálio , Tomografia por Emissão de Pósitrons , Animais , Linhagem Celular Tumoral , Exenatida , Humanos , Rim , Camundongos
8.
Cell Physiol Biochem ; 46(6): 2471-2479, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29742489

RESUMO

BACKGROUND/AIMS: To investigate the impact of renal denervation (RDN) on myocardial fibrosis and ventricular arrhythmias (VAs) in rats with ischemic cardiomyopathy. METHODS: An ischemic cardiomyopathy model was reproduced with myocardial infarction (MI) in adult Sprague-Dawley male rats. The RDN/Sham-RDN procedure was performed at 2 weeks after MI. Sham-MI and sham-RDN rats served as the control group. At 4 weeks after RDN, programmed electrical stimulation (PES) was used to induce VAs, including ventricular tachycardia and ventricular fibrillation, in all 3 groups (MI+RDN, MI, and control groups). At the end of PES, heart and kidney samples were harvested. Immunofluorescence labeling was used to investigate the distribution of connexin 43 (Cx43) in the infarcted border zone. Masson's trichrome stain was adopted to determine the degree of cardiac fibrosis. Western blotting was performed to identify the expression of transforming growth factor beta 1 (TGF-ß1), α-smooth muscle actin (α-SMA), and Cx43. An enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of B-type natriuretic peptide (BNP) and the amino-terminal pro-peptides of type I and III collagen (PINP and PIIINP, respectively) and the expression level of renal norepinephrine. RESULTS: Compared with the MI group, RDN significantly decreased the inducibility of VAs (MI+RDN 3/8 rats vs. MI 8/9 rats, P < 0.05; control 1/8 rats) with PES, reduced myocardial fibrosis estimated by collagen volume fraction (MI+RDN 31.10 ± 3.97% vs. MI 54.80 ± 16.39%, P < 0.001; control 4.41 ± 0.92% ), suppressed TGF-ß1 (P < 0.01) and α-SMA (P < 0.001) levels, and attenuated both PINP (MI+RDN 41.44 ± 10.10 ng/mL vs. MI 95.49 ± 24.83 ng/mL, P < 0.001; control 11.90 ± 4.96 ng/mL) and PIIINP (MI+RDN 82.12 ± 30.79 ng/mL vs. MI 124.60 ± 26.64 ng/mL, P < 0.05; control 64.69 ± 23.84 ng/mL) levels. Moreover, RDN reversed the abnormal myocardial distribution of Cx43 and its reduction by MI damage (P < 0.01). CONCLUSIONS: RDN reduced myocardial fibrosis and suppressed VAs in a rat model of ischemic cardiomyopathy.


Assuntos
Arritmias Cardíacas/terapia , Cardiomiopatias/terapia , Denervação , Ventrículos do Coração/patologia , Rim/inervação , Isquemia Miocárdica/terapia , Miocárdio/patologia , Animais , Arritmias Cardíacas/patologia , Cardiomiopatias/patologia , Denervação/métodos , Fibrose , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Isquemia Miocárdica/patologia , Ratos Sprague-Dawley
9.
J Org Chem ; 83(11): 6006-6014, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29750511

RESUMO

A practical and scalable single electron transfer reduction mediated by sodium dispersions has been developed for the reduction and reductive deuteration of tertiary amides. The chemoselectivity of this method highly depends on the nature of the proton donor. The challenging reduction via C-N bond cleavage has been achieved using Na/EtOH, affording alcohol products, while the use of Na/NaOH/H2O leads to the formation of amines via selective C-O scission. Sodium dispersions with high specific surface areas are crucial to obtain high yields and good chemoselectivity. This new method tolerates a range of tertiary amides. Moreover, the corresponding reductive deuterations mediated by Na/EtOD- d1 and Na/NaOH/D2O afford useful α,α-dideuterio alcohols and α,α-dideuterio amines with an excellent deuterium content.

10.
Cell Rep ; 43(6): 114348, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38865245

RESUMO

The cortex and cerebellum form multi-synaptic reciprocal connections. We investigate the functional connectivity between single spiking cerebellar neurons and the population activity of the mouse dorsal cortex using mesoscale imaging. Cortical representations of individual cerebellar neurons vary significantly across different brain states but are drawn from a common set of cortical networks. These cortical-cerebellar connectivity features are observed in mossy fibers and Purkinje cells as well as neurons in different cerebellar lobules, albeit with variations across cell types and regions. Complex spikes of Purkinje cells preferably associate with the sensorimotor cortex, whereas simple spikes display more diverse cortical connectivity patterns. The spontaneous functional connectivity patterns align with cerebellar neurons' functional responses to external stimuli in a modality-specific manner. The tuning properties of subsets of cerebellar neurons differ between anesthesia and awake states, mirrored by state-dependent changes in their long-range functional connectivity patterns with mesoscale cortical activity.


Assuntos
Cerebelo , Animais , Camundongos , Cerebelo/fisiologia , Masculino , Células de Purkinje/fisiologia , Camundongos Endogâmicos C57BL , Vias Neurais/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Feminino
11.
Environ Sci Pollut Res Int ; 31(29): 41844-41853, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38866932

RESUMO

Biological degradation method, as an environmentally friendly, low-carbon, and clean pollution treatment technology, is widely used for the harmless disposal of oily sludge. The biodegradability of oily sludge with stable emulsification system, high oil, and water content is poor. Therefore, it is necessary to pre-treat the oily sludge to improve its biodegradability, including recover the petroleum resources and remove heavy metals and bio-toxic organic matters. This review systematically summarizes five oily sludge treatment methods and their influences on sludge biodegradability, including pyrolysis, chemical hot washing, solvent extraction, chemical oxidation, and hydrothermal. Pyrolysis at temperatures above 750 °C produces high molecular weight polycyclic aromatic hydrocarbons, chemical hot washing and chemical oxidation would cause secondary pollution, solvent extraction method could not be applied due to the high cost and high toxicity of the extractant, and the oil removal of hydrothermal method is inefficient. Additionally, the principles, advantages, and disadvantages of those treatments and the factors affecting microbial degradation were analyzed, which provide the development direction of pretreatment technology to improve the biodegradability of oily sludge.


Assuntos
Biodegradação Ambiental , Petróleo , Esgotos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos
12.
Mol Biotechnol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771422

RESUMO

The occurrence of osteoarthritis in the knee joint is regulated by a complex network, and there is currently no specific therapeutic drug available. Functional exercises and treatments targeting inflammatory factors have shown the potential to alleviate knee osteoarthritis to some extent. Therefore, the aim of this study was to assess the intra-articular injection (IAI) of autologous platelet-rich plasma (PRP) combined with physical therapy (PT) in treating knee osteoarthritis. A total of 128 patients with knee osteoarthritis were included in the study, including 64 males and 64 females. A total of 128 patients were divided into sodium hyaluronate group (HA group), PRP group, PRP + PT group, and PT group, with 32 cases in each group. Visual analog scale (VAS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and Japanese Orthopaedic Association (JOA) were employed to evaluate the recovery of patients from pain and osteoarthritis. Color Doppler ultrasound imaging technology was utilized to assess joint effusion, synovial membrane thickness, and articular cartilage thickness in patients with knee osteoarthritis. Enzyme-linked immunosorbent assay (ELISA) was employed to detect the levels of interleukin-1ß (IL-1ß), transforming growth factor-ß1 (TGF-ß1), and matrix metallopeptidase 3 (MMP-3) in the synovial fluid. Compared to the HA group, the PT group, PRP group, and PRP combined with PT (PRP + PT) group all showed reduced VAS and WOMAC scores, increased JOA scores, decreased joint effusion, synovial membrane thickness, and articular cartilage thickness in the knee joint. Additionally, levels of IL-1ß and MMP-3 in the synovial fluid decreased, while TGF-ß1 levels increased (P < 0.05). Compared with the PT group, the VAS and WOMAC scores of the knee joint in the PRP group decreased, JOA scores increased, joint effusion, synovial thickness, and articular cartilage thickness decreased, but there was no statistically significant difference (P > 0.05), and the PRP + PT group showed decreased VAS and WOMAC scores, increased JOA scores, reduced joint effusion, synovial membrane thickness, and articular cartilage thickness in the knee joint. Moreover, levels of IL-1ß and MMP-3 in the synovial fluid decreased, while TGF-ß1 levels increased (P < 0.05). No severe adverse reactions were observed in any of the four groups, but the pain rate in the PRP + TP group was significantly lower than PT group, PRP group, and PRP + PT group (P < 0.05). The efficacy of intra-articular injection of PRP combined with exercise therapy in the treatment of knee osteoarthritis is superior to that of single interventions such as simple interventions of HA, PRP injection, and PT. Furthermore, intra-articular injection of PRP combined with exercise therapy demonstrates enhanced effectiveness in improving the inflammatory levels associated with knee osteoarthritis and facilitating the rehabilitation process.

13.
Elife ; 122023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37962180

RESUMO

Brain function originates from hierarchical spatial-temporal neural dynamics distributed across cortical and subcortical networks. However, techniques available to assess large-scale brain network activity with single-neuron resolution in behaving animals remain limited. Here, we present Mesotrode that integrates chronic wide-field mesoscale cortical imaging and compact multi-site cortical/subcortical cellular electrophysiology in head-fixed mice that undergo self-initiated running or orofacial movements. Specifically, we harnessed the flexibility of chronic multi-site tetrode recordings to monitor single-neuron activity in multiple subcortical structures while simultaneously imaging the mesoscale activity of the entire dorsal cortex. A mesoscale spike-triggered averaging procedure allowed the identification of cortical activity motifs preferentially associated with single-neuron spiking. Using this approach, we were able to characterize chronic single-neuron-related functional connectivity maps for up to 60 days post-implantation. Neurons recorded from distinct subcortical structures display diverse but segregated cortical maps, suggesting that neurons of different origins participate in distinct cortico-subcortical pathways. We extended the capability of Mesotrode by implanting the micro-electrode at the facial motor nerve and found that facial nerve spiking is functionally associated with the PTA, RSP, and M2 network, and optogenetic inhibition of the PTA area significantly reduced the facial movement of the mice. These findings demonstrate that Mesotrode can be used to sample different combinations of cortico-subcortical networks over prolonged periods, generating multimodal and multi-scale network activity from a single implant, offering new insights into the neural mechanisms underlying specific behaviors.


Assuntos
Mapeamento Encefálico , Córtex Cerebral , Camundongos , Animais , Mapeamento Encefálico/métodos , Neurônios/fisiologia , Fenômenos Eletrofisiológicos , Nervos Periféricos
14.
3D Print Addit Manuf ; 10(3): 524-535, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37346191

RESUMO

Wire and arc additive manufacturing (WAAM) is becoming a promising technique due to its high deposition rate and low cost. However, WAAM faces challenges of coarse grains. In this study, a novel in situ vibration method was proposed to suppress these imperfections of WAAM. Temperature and vibration distributions were explored first, and the optimized parameters were utilized for manufacturing low-carbon steel parts. The results revealed that after the vibration, the average grain size in fine grain zone was reduced from 9.8 to 7.1 µm, and that in coarse grain zone was declined from 10.6 to 7.4 µm, respectively. No large deformation occurred due to the low temperature. Grain refining was attributed to more dendrite fragments induced by excessive stress at the roots of dendrites. The refined grains enhanced mechanical strength of the parts in both X and Z directions and improved the average hardness. After the vibration, the ultimate tensile strength and yield strength were increased to 522.5 and 395 MPa, which represented an increase of 10% and 13.8%, respectively. The average hardness was improved to 163 HV, which was an increase of 10.1%.

15.
Metabolites ; 13(11)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37999245

RESUMO

Breast milk is widely considered to be the most natural, safe, and complete food for infants. However, current breastfeeding rates fall short of the recommendations established by the World Health Organization. Despite this, there are few studies that have focused on the promotion of human lactation through nutrient supplementation. Therefore, the aim of this study was to investigate the effect of methionine on milk synthesis in human mammary epithelial cells (MCF-10A cells) and to explore the underlying mechanisms. To achieve this, MCF-10A cells were cultured with varying concentrations of methionine, ranging from 0 to 1.2 mM. Our results indicated that 0.6 mM of methionine significantly promoted the synthesis of milk protein. An RNA-seq analysis revealed that methionine acted through the PI3K pathway. This finding was validated through real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. In addition, PI3K inhibition assays confirmed that methionine upregulated the expression of both mTOR and p-mTOR through activation of PI3K. Taken together, these findings suggest that methionine positively regulates milk protein synthesis in MCF-10A cells through the PI3K-mTOR signaling pathway.

16.
J Gen Physiol ; 154(7)2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35612552

RESUMO

Voltage-gated sodium (Nav) channels produce the upstroke of action potentials in excitable tissues throughout the body. The gating of these channels is determined by the asynchronous movements of four voltage-sensing domains (VSDs). Past studies on the skeletal muscle Nav1.4 channel have indicated that VSD-I, -II, and -III are sufficient for pore opening, whereas VSD-IV movement is sufficient for channel inactivation. Here, we studied the cardiac sodium channel, Nav1.5, using charge-neutralizing mutations and voltage-clamp fluorometry. Our results reveal that both VSD-III and -IV are necessary for Nav1.5 inactivation, and that steady-state inactivation can be modulated by all VSDs. We also demonstrate that channel activation is partially determined by VSD-IV movement. Kinetic modeling suggests that these observations can be explained from the cardiac channel's propensity to enter closed-state inactivation (CSI), which is significantly higher than that of other Nav channels. We show that skeletal muscle Nav1.4, cardiac Nav1.5, and neuronal Nav1.6 all have different propensities for CSI and postulate that these differences produce isoform-dependent roles for the four VSDs.


Assuntos
Ativação do Canal Iônico , Canais de Sódio , Potenciais de Ação/fisiologia , Potenciais da Membrana/fisiologia , Isoformas de Proteínas/genética , Canais de Sódio/genética
17.
Zhongguo Gu Shang ; 35(5): 423-9, 2022 May 25.
Artigo em Zh | MEDLINE | ID: mdl-35535529

RESUMO

OBJECTIVE: To investigate the effects of different bone cement morphology distribution on the clinical efficacy of unilateral percutaneous vertebroplasty(PVP) for spinal osteoporotic fractures. METHODS: The clinical data of 66 patients with osteoporotic vertebral compression fractures received unilateral PVP treatment from January 2019 to April 2020 were retrospectively analyzed. There were 16 males and 50 females, including 83 vertebral bodies, 45 thoracic vertebrae and 38 lumbar vertebrae, and 55 patients with single-segment, 6 double-segment, 4 three-segment and 1 four-segment. The age ranged from 60 to 93 years with an average of (76.83±8.65) years. The included patients were admitted to hospital 1 to 10 days after onset, and were diagnosed by anteroposterior and lateral X-rays, MRI and bone density examination before surgery. According to the shape of bone cement in postoperative X-ray, the patients were divided into O-shaped group (28 cases) and H-shaped group (38 cases). In O-shaped group, the bone cement presented agglomeration mass distribution in the affected vertebra in postoperative X-ray while the bone cement presented disseminated honeycomb distribution in the affected vertebrae in H-shaped group. Bone cement injection volume was collected in two groups. The intraoperative bone cement leakage and postoperative adjacent vertebral fractures were observed. The VAS of the two groups before operation and 1 day, 1 month, 6 months and 1 year after operation were compared;and ODI of the two groups 1 day, 6 months and 1 year after operation were compared. The kyphosis angle and anterior height of the affected vertebrae were measured before operation and 1 week, 1 year after operation. RESULTS: All 66 patients completed 1-year follow-up, and all patients healed well at the puncture site after surgery. There were 1 case and 8 cases of bone cement leakage in O-shaped group and H-shaped group during surgery respectively (P<0.05), but no serious complications occurred. One case occurred adjacent vertebral fracture in both groups during one-year follow-up (P>0.05). There was no statistical significance in injection amount of bone cement between the two groups (P>0.05). The VAS scores of O-shaped group and H-shaped group were 7.89±0.79, 2.75±1.08, 0.46±0.58, 0.36±0.49 and 8.00±1.04, 2.58±1.15, 0.53±0.56, 0.42±0.50 before operation, 1 day, 6 months, 1 year after operation respectively, and there was no statistical significance(P>0.05), and the VAS scores were 0.96±0.58 and 1.18±0.83 at 1 month after operation respectively, with statistical significance(P<0.05). The ODI scores of O-shaped group and H-shaped group were 12.43±3.78, 10.00±2.46, 8.43±1.50 and 12.11±3.68, 9.53±2.35, 8.32±1.51 at 1 day, 6 months and 1 year after surgery respectively, and there was no statistical significance between the two groups(P>0.05). There were no statistical significance in kyphotic angles and anterior height before surgery and 1 week, 1 year after surgery between two groups (P>0.05). CONCLUSION: No matter the distribution of bone cement is O-shape or H-shape, it can achieve good clinical effect, and the prognosis effect is equivalent. Therefore, when performing unilateral puncture PVP surgery, it is not necessary to deliberately increase the puncture angle of the puncture needle in order to achieve the full diffusion of the affected vertebrae, so as to reduce the risk of damaging important structures and bone cement leakage.


Assuntos
Fraturas por Compressão , Cifose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Idoso , Idoso de 80 Anos ou mais , Cimentos Ósseos/uso terapêutico , Feminino , Fraturas por Compressão/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Punção Espinal , Resultado do Tratamento
18.
J Gen Physiol ; 154(5)2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35297947

RESUMO

Alternative splicing is an important cellular mechanism that fine tunes the gating properties of both voltage- and ligand-gated ion-channels. The cardiac voltage-gated sodium channel, Nav1.5, is subject to alternative splicing of the DI S3-S4 linker, which generates two types of channels with different activation properties. Here, we show that the gating differences between the adult (mH1) and neonatal (Nav1.5e) isoforms of Nav1.5 are mediated by two amino acid residues: Thr/Ser at position 207 and Asp/Lys at position 211. Electrophysiological experiments, in conjunction with molecular dynamics simulations, revealed that each residue contributes equally to the overall gating shifts in activation, but that the underlying structural mechanisms are different. Asp/Lys at position 211 acts through electrostatic interactions, whereas Thr/Ser at position 207 is predicted to alter the hydrogen bond network at the top of the S3 helix. These distinct structural mechanisms work together to modify movement of the voltage-sensitive S4 helix to bring about channel activation. Interestingly, mutation of the homologous Asp and Thr residues of the skeletal muscle isoform, Nav1.4, to Lys and Ser, respectively, confers a similar gating shift in channel activation, suggesting that these residues may fulfill a conserved role across other Nav channel family members.


Assuntos
Canais de Sódio Disparados por Voltagem , Adulto , Fenômenos Eletrofisiológicos , Humanos , Recém-Nascido , Simulação de Dinâmica Molecular , Mutação , Canal de Sódio Disparado por Voltagem NAV1.5 , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Canais de Sódio Disparados por Voltagem/metabolismo
19.
Front Pharmacol ; 13: 862581, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431943

RESUMO

Purpose: To assess the significance of mutation mutual exclusion information in the optimization of radiomics algorithms for predicting gene mutation. Methods: We retrospectively analyzed 258 non-small cell lung cancer (NSCLC) patients. Patients were randomly divided into training (n = 180) and validation (n = 78) cohorts. Based on radiomics features, radiomics score (RS) models were developed for predicting KRAS proto-oncogene mutations. Furthermore, a composite model combining mixedRS and epidermal growth factor receptor (EGFR) mutation status was developed. Results: Compared with CT model, the PET/CT radiomics score model exhibited higher AUC for predicting KRAS mutations (0.834 vs. 0.770). By integrating EGFR mutation information into the PET/CT RS model, the AUC, sensitivity, specificity, and accuracy for predicting KRAS mutations were all elevated in the validation cohort (0.921, 0.949, 0.872, 0.910 vs. 0.834, 0.923, 0.641, 0.782). By adding EGFR exclusive mutation information, the composite model corrected 64.3% false positive cases produced by the PET/CT RS model in the validation cohort. Conclusion: Integrating EGFR mutation status has potential utility for the optimization of radiomics models for prediction of KRAS gene mutations. This method may be used when repeated biopsies would carry unacceptable risks for the patient.

20.
Environ Pollut ; 306: 119369, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35513195

RESUMO

Electronic waste (e-waste) pollution is of great concern due to the release of hazardous chemicals during the improper e-waste disposal. Many chemicals leached from e-waste were reported to pose estrogenic effects. To date, little is known regarding the occurrence and biological effects of estrogenic chemicals in sediments near an e-waste area. In this study, an effect-directed analysis (EDA) is applied to determine the estrogenic chemicals in sediments of four sites collected from a typical e-waste recycling city in China. Following screening with the ER-CALUX assay, the extract of sample with the most potent effect was subjected in fractionation using reverse phase liquid chromatography. Based on a target analysis for the active fractions, four compounds, including estrone, 17ß-estradiol, 17α-ethinylestradiol and bisphenol A, were identified, and these contributed to 17% of the total toxic effects in the sample. A further nontarget analysis screened four candidates, namely diethylstilbestrol (DES), hexestrol (HES), nandrolone and durabolin, and the total contribution was found to be 48% from the active sample. Specifically, DES and HES were only detected in the active sample and were found to be the primary drivers of estrogenic effects. An examination of the identified chemicals in the four sites indicated that these estrogenic chemicals may originate from e-waste recycling, livestock excretion and domestic waste. These findings uncovered the estrogenic pollutants in sediments from an e-waste area. Considering single endpoint in biological assay is not abundant to screen chemicals with different toxic effects, further EDA studies with multiple endpoints are required to better understand the occurrence of representative or unknown chemicals in e-waste-polluted areas.


Assuntos
Resíduo Eletrônico , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Estrogênios/análise , Estrona/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
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