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1.
Int J Mol Sci ; 25(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39273411

RESUMO

There are great challenges in the field of natural product isolation and purification and in the pharmacological study of oligosaccharide monomers. And these isolation and purification processes are still universal problems in the study of natural products (NPs), traditional Chinese medicine (TCM), omics, etc. The same polymer-modified materials designed for the special separation of oligosaccharides, named Sil-epoxy-PEI and Sil-chloropropyl-PEI, were synthesized via two different methods and characterized by scanning electron microscopy combined with energy spectrum analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential as well as surface area analysis, etc. Several nucleotide/nucleoside molecules with different polarities and selectivities were successfully isolated in our laboratory using stainless-steel columns filled with the synthesized material. In addition, the separation of saccharide probes and oligosaccharides mixtures in water extracts of Morinda officinalis were compared in HILIC mode. The results showed that the resolution of separations for the representative analytes of the Sil-epoxy-PEI column was higher than for the Sil-chloropropyl-PEI column, and the developed stationary phase exhibited improved performance compared to hydrothermal carbon, amide columns and other HILIC materials previously reported.


Assuntos
Oligossacarídeos , Polietilenoimina , Dióxido de Silício , Oligossacarídeos/química , Oligossacarídeos/síntese química , Oligossacarídeos/isolamento & purificação , Polietilenoimina/química , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Bioresour Technol ; : 131547, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39343176

RESUMO

This study explores the physicochemical attributes of dissolved organic matter from rice straw biochar (BDOM) at varying pyrolysis temperatures and photo-irradiation conditions, focusing on the binding mechanisms of phenanthrene (PHE) and 9-phenanthrol (PTR) using multiple spectroscopic techniques and fluorescence quenching. Following 20 h of photo-irradiation, only 11.3 % of BDOM underwent mineralization, forming new CH3/CH2/CH aliphatics structures. BDOM from biochar produced by pyrolysis at 400°C exhibited a stronger binding affinity with PHE and PTR, achieving 44 % and 52 % maximum binding, respectively. Static and dynamic quenching governed PHE and PTR binding, which was influenced by temperature. Photo-irradiated BDOM showed enhanced binding with PHE, attributed to increased aliphatic content. Hydrogen bond and π-π electron-donor-acceptor (EDA) interactions dominated PTR binding, while π-π interactions and hydrophobic interactions controlled PHE. This study provides valuable insights into BDOM photochemical behaviors and their impact on the environmental fate of polycyclic aromatic hydrocarbons (PAHs) after BDOM photo-irradiation.

3.
Bioorg Chem ; 151: 107686, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111120

RESUMO

A series of novel quinazoline-derived EGFR/HER-2 dual-target inhibitors were designed and synthesized by heterocyclic-containing tail approach. The inhibitory activities against four human epidermal growth factor receptor (HER) isozymes (EGFR, HER-2, HER-3 and HER-4) of all new compounds so designed were investigated in vitro. Compound 12k was found to be the most effective and rather selective dual-target inhibitor of EGFR and HER-2 with inhibitory constant (IC50) values of 6.15 and 9.78 nM, respectively, which was more potent than the clinical used agent Lapatinib (IC50 = 8.41 and 9.41 nM). Meanwhile, almost all compounds showed excellent antiproliferative activities against four cancer cell models (A549, NCI-H1975, SK-BR-3 and MCF-7) and low damage to healthy cells. Among them, compound 12k also exhibited the most prominent antitumor activity. Moreover, the hit compound 12k could bind to EGFR and HER-2 stably in molecular docking and dynamics studies. The following wound healing assay revealed that compound 12k could inhibit the migration of SK-BR-3 cells. Further studies found that compound 12k could arrest cell cycle in the G0/G1 phase and induce SK-BR-3 cells apoptosis. Notably, compound 12k could effectively inhibit breast cancer growth with little toxicity in the SK-BR-3 cell xenograft model. Taken together, in vitro and in vivo results disclosed that compound 12k had high drug potential as a dual-target inhibitor of EGFR/HER-2 to inhibit breast cancer growth.


Assuntos
Antineoplásicos , Proliferação de Células , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB , Inibidores de Proteínas Quinases , Quinazolinas , Receptor ErbB-2 , Humanos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Quinazolinas/farmacologia , Quinazolinas/química , Quinazolinas/síntese química , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Estrutura Molecular , Animais , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Camundongos , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular , Apoptose/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/química , Compostos Heterocíclicos/síntese química , Feminino
4.
ChemSusChem ; : e202400168, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041861

RESUMO

Silicon-based anodes are becoming promising materials due to their high specific capacity. However, the intrinsically large volume change brought about by the alloying reaction results in the crushing of the active particles and destruction of the electrode structure, which severely limits its practical application. Various structured and modified silica-based anodes exhibit improved cycling stability and the demonstrated ability to mitigate their volume changes through interfacial and binder strategies. However, the issue of large volume changes in silicon-based anodes remains. Herein, we report a gel polymer electrolyte (GPE) prepared through an in situ thermal polymerization process that is suitable for SiOx anode materials and achieving long-term cycling stability. GPE-based cells essentially mitigate the volume change of SiOx anodes by guiding the unique lithiation/delithiation mechanism that tends to favor the formation and delithiation of amorphous-LixSi (a-LixSi) with smaller volume change, thereby mitigating electrode damage and cracking, and achieving the significant improvement in cycling performance. The prepared GPE-SiOx cells retained 693.80 mAh g-1 reversible capacity after 450 cycles at 500 mA g-1. In addition, the prelithiation process was incorporated to mitigate capacity fluctuations and improve the Initial Coulombic Efficiency (ICE), and a reversible capacity of 641.90 mAh g-1 was retained after 480 cycles.

5.
Front Immunol ; 15: 1375168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690287

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma. The HTLV-1 Tax constitutively activates nuclear factor-κB (NF-κB) to promote the survival and transformation of HTLV-1-infected T cells. Despite extensive study of Tax, how Tax interacts with host factors to regulate NF-κB activation and HTLV-1-driven cell proliferation is not entirely clear. Here, we showed that overexpression of Poly (rC)-binding protein 1 (PCBP1) promoted Tax-mediated IκB kinase (IKK)-NF-κB signaling activation, whereas knockdown of PCBP1 attenuated Tax-dependent IKK-NF-κB activation. However, Tax activation of HTLV-1 long terminal repeat was unaffected by PCBP1. Furthermore, depletion of PCBP1 led to apoptosis and reduced proliferation of HTLV-1-transformed cells. Mechanistically, PCBP1 interacted and co-localized with Tax in the cytoplasm, and PCBP1 KH3 domain was indispensable for the interaction between PCBP1 and Tax. Moreover, PCBP1 facilitated the assembly of Tax/IKK complex. Collectively, our results demonstrated that PCBP1 may exert an essential effect in Tax/IKK complex combination and subsequent NF-κB activation, which provides a novel insight into the pathogenetic mechanisms of HTLV-1.


Assuntos
Proteínas de Ligação a DNA , Produtos do Gene tax , Ribonucleoproteínas Nucleares Heterogêneas , Vírus Linfotrópico T Tipo 1 Humano , NF-kappa B , Proteínas de Ligação a RNA , Humanos , Produtos do Gene tax/metabolismo , NF-kappa B/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Transdução de Sinais , Células HEK293 , Ligação Proteica , Proliferação de Células , Infecções por HTLV-I/metabolismo , Infecções por HTLV-I/virologia , Apoptose , Quinase I-kappa B/metabolismo , Interações Hospedeiro-Patógeno
6.
Accid Anal Prev ; 195: 107421, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061291

RESUMO

Accurately and quickly mining the hidden information in railway dangerous goods transportation (RDGT) accident reports has great significance for its safety management. In this paper, a data mining method Logistics-DT-TFP is proposed for analysing the causes of RDGT accidents. Firstly, analyse the transportation process, extract the cause of the accident, and classify the severity of the accident. Then, using ordered multi-classification Logistic regression for correlation calculation, qualitatively judge and quantitatively analyse the relationship between each cause and the severity of the accident. The feature tags of the Decision Tree (DT) are screened, the C5.0 algorithm is used to obtain the accident coupling rules. Next, the FP-Growth algorithm is used to mine frequent itemsets, and TOP-K is used to improve it and output effective association rules with the degree of lift as the indicator, which avoids repeated traversal of the database, shortens the time complexity, and reduces the impact of the minimum support setting on the calculation results. The degree of lift among the causes in the coupling chain is calculated as a complement to the extraction of coupling rules. Finally, based on the analysis and mining results of case study, the management strategies for railway dangerous goods are proposed.


Assuntos
Acidentes de Trânsito , Meios de Transporte , Humanos , Causalidade , Mineração de Dados/métodos , Algoritmos
7.
Langmuir ; 39(45): 16151-16162, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37910769

RESUMO

This study presented a novel modification method for fine SiC powder by using sodium lignosulfonate as a dispersant. The adsorption behavior of sodium lignosulfonate on the SiC/water interface and its effect on the performance of a fine SiC slurry were systematically investigated. The adsorption results showed that sodium lignosulfonate formed monolayer adsorption on the surface of fine SiC and that the saturated adsorption capacity was 1.3263 mg/g. The adsorption reached equilibrium within 3 h and was mainly controlled by active sites on the SiC surface. The dispersion, stability, and zeta potential of modified SiC powder were improved after sodium lignosulfonate adsorption. The zeta potential of modified SiC reached a minimum value of -44.8 mV at pH 12. Modified SiC suspensions had great stability in a wider pH range of 6-12. Modified SiC slurry with 54 vol % solid loading had a low viscosity of 173 mPa·s at pH 10. Subsequently, coarse SiC powder was added for slip casting. A mixed slurry with high solid loading (69 vol %) and low viscosity (583 mPa·s) was prepared using modified SiC and coarse SiC powders at a mass ratio of 2:3. Finally, recrystallized SiC green body with high density (2.6492 g/cm3) was obtained.

8.
Materials (Basel) ; 16(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37763548

RESUMO

Triphenylphosphine acetylacetone carbonyl rhodium (ROPAC) is an important catalyst in the petrochemical industry, and its deactivated waste catalyst holds significant value for recovery. This study focuses on the existing forms of rhodium (Rh) in waste catalysts and the current status of traditional processes. A green, efficient, and continuous recovery technique was developed using a sealed stainless steel microchannel reactor. The influence of reaction temperature, reaction time, and phase ratio on the Rh recovery rate was investigated, and the process parameters were optimized using response surface methodology (RSM). The results indicate that the magnitude of the impact on the Rh recovery rate follows the order: reaction temperature > reaction time > phase ratio. The optimized process parameters were determined as follows: a reaction time of 29 min, a reaction temperature of 110 °C, and a phase ratio of 1:1, with a corresponding maximum recovery rate of Rh of 66.06%. Furthermore, secondary treatment was performed on the organic phase after primary recovery using the same process conditions, resulting in an overall Rh recovery rate of 95.6%, indicating satisfactory recovery efficiency. Moreover, the application of FTIR and ICP-OES analysis provided definitive evidence that the oxidative dissociation of the rhodium-phosphine chemical bond by H2O2 within ROPAC leads to the conversion of Rh+ into Rh3+. Subsequently, Rh forms chloroaquorhodium (III) complexes that enter the aqueous phase, enabling effective recovery of Rh.

9.
Front Nutr ; 10: 1222536, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736138

RESUMO

Objective: Previous cohort trials have shown that skipping breakfast increases the risk of obesity or overweight in children. However, this finding remains controversial. Through a meta-analysis, this study systematically evaluated the effect of skipping breakfast on the prevalence of obesity or overweight in children. Methods: We performed a literature search for studies published until March 19, 2023. using the Cochrane, PubMed, and Embase databases. Based on the inclusion and exclusion criteria, observational studies on the relationship between skipping breakfast and overweight/obesity in children and adolescents were analyzed. Three investigators independently screened the relevant literature, extracted the data, and assessed the risk of bias. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). A random-effects model was used. The odds ratio (OR) with its 95% confidence interval (CI) was used to indicate the effect size. Results: A total of 40 retrospective studies with 323,244 children ranging in age from 2 to 20 years were included in this study. The results of this meta-analysis showed that children and adolescents who skipped breakfast had a significantly higher prevalence of obesity or overweight than those who ate breakfast (OR, 1.59; 95% CI, 1.33-1.90; P < 0.001). Skipping breakfast was positively associated with overweight in children and adolescents (OR, 1.37; 95% CI, 1.23-1.54; P < 0.001). Similarly, skipping breakfast was positively associated with obesity in children and adolescents (OR, 1.51; 95% CI, 1.30-1.76; P < 0.001). The effect was also different by sex, with girls being the most affected (OR, 1.47; 95% CI, 1.23-1.76; P < 0.001). There was also a correlation between skipping breakfast and abdominal obesity in children (OR, 0.65; 95% CI, 0.55-0.77; P < 0.001). Conclusion: This meta-analysis suggested that skipping breakfast is associated with an increased risk of overweight/obesity in children and adolescents. The findings provide support for a possible protective role of breakfast against excessive weight gain in children and adolescents. However, more rigorous study designs with validated and standardized measures of relevant variables are needed.

10.
Int J Mol Sci ; 24(15)2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37569875

RESUMO

The natural healing process of bone is impaired in the presence of tumors, trauma, or inflammation, necessitating external assistance for bone regeneration. The limitations of autologous/allogeneic bone grafting are still being discovered as research progresses. Bone tissue engineering (BTE) is now a crucial component of treating bone injuries and actively works to promote vascularization, a crucial stage in bone repair. A biomaterial with hydroxyapatite (HA), which resembles the mineral makeup of invertebrate bones and teeth, has demonstrated high osteoconductivity, bioactivity, and biocompatibility. However, due to its brittleness and porosity, which restrict its application, scientists have been prompted to explore ways to improve its properties by mixing it with other materials, modifying its structural composition, improving fabrication techniques and growth factor loading, and co-cultivating bone regrowth cells to stimulate vascularization. This review scrutinizes the latest five-year research on HA composite studies aimed at amplifying vascularization in bone regeneration.


Assuntos
Engenharia Biomédica , Durapatita , Durapatita/química , Engenharia Tecidual/métodos , Osso e Ossos , Materiais Biocompatíveis , Regeneração Óssea , Alicerces Teciduais/química
11.
Oncol Lett ; 25(6): 253, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37205916

RESUMO

Hepatic epithelioid hemangioendothelioma (HEHE) is a rare liver tumor, which is usually diagnosed by pathological examination, since the diagnostic imaging criteria remain to be defined. However, contrast-enhanced ultrasound (CEUS) may reveal the characteristic features of HEHE to aid diagnosis. In the present study, two-dimensional ultrasound examination of a 38-year-old male patient showed a mass in the right liver. CEUS showed an S5 segment hypoechoic nodule, and imaging features resulted in the diagnosis of HEHE. Surgery was shown to be an appropriate and successful treatment for HEHE. In conclusion, CEUS may be valuable for the diagnosis of HEHE, thereby avoiding the serious consequences of misdiagnosis.

12.
Environ Sci Pollut Res Int ; 30(24): 66303-66313, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37097559

RESUMO

In this study, ferrous composites (FexO4) were prepared by microreactor to activate peroxydisulfate (PDS) for the degradation of bisphenol A (BPA) with visible (Vis) light irradiation. X-ray diffraction (XRD), energy-dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) were used to characterize the morphology and crystal phase of FeXO4. Photoluminescence (PL) spectroscopy combined with amperometric tests were used to determine the role of PDS on the performance of photocatalytic reaction. The main reactive species and intermediates for BPA removal were determined by electron paramagnetic resonance (EPR) measurement and quenching experiments. The result indicated that singlet state oxygen (1O2) contributed more to the BPA degradation than that of other reactive radicals (·OH, SO4·- and ·O2-); these reactive radicals and 1O2 formed by the reaction between photo-generated electrons (e-) and holes (h+) of FexO4 and PDS. During this process, the consumption of e- and h+ also improved their separation efficiency and thus enhanced the degradation of BPA. In addition, the photocatalytic activity of FexO4 in Vis/FexO4/PDS system was 3.2-fold and 6.6-fold higher than that of single FexO4 and PDS under Vis light, respectively. The Fe2+/Fe3+ cycle could effectively drive the photocatalytic activation of PDS through indirect electron transfer and the formation of reactive radicals. This work illustrated that the degradation of BPA was rapidly in Vis/FexO4/PDS system mainly through 1O2, which further improve our understanding on the efficient removal of organic contaminants in the environment.


Assuntos
Oxigênio , Oxigênio Singlete , Luz , Fenóis/química
13.
Langmuir ; 39(16): 5679-5688, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37040602

RESUMO

Emerging pollutants, such as sulfonamide antibiotics and pharmaceuticals, have been widely detected in water and soils, posing serious environmental and human health concerns. Thus, it is urgent and necessary to develop a technology for removing them. In this work, a hydrothermal carbonization method was used to prepare the hydrochars (HCs) by pine sawdust with different temperatures. To improve the physicochemical properties of HCs, phosphoric acid (H3PO4) and hydrogen peroxide (H2O2) were used to modify these HCs, and they were referred to as PHCs and HHCs, respectively. The adsorption of sulfamethoxazole (SMX) and carbamazepine (CBZ) by pristine and modified HCs was investigated systematically. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results indicated that the H2O2/H3PO4 modification led to the formation of a disordered carbon structure and abundant pores. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy results suggested that carboxyl (-COOH) and hydroxyl (-OH) functional groups of HCs increased after modification, which is the main reason for the higher sorption of SMX and CBZ on H3PO4/H2O2-modified HCs when compared with pristine HCs. In addition, the positive correlation between -COOH/C=O and logKd of these two chemicals also suggested that oxygen-containing functional groups played a crucial role in the sorption of SMX and CBZ. The strong hydrophobic interaction and π-π interaction between CBZ and pristine/modified HCs resulted in its higher adsorption when compared with SMX. The results of this study provide a novel perspective on the investigation of adsorption mechanisms and environmental behaviors for organic contaminants by pristine and modified HCs.


Assuntos
Sulfametoxazol , Poluentes Químicos da Água , Humanos , Sulfametoxazol/química , Peróxido de Hidrogênio , Carvão Vegetal/química , Oxigênio , Adsorção , Carbamazepina/análise , Carbamazepina/química , Poluentes Químicos da Água/análise , Cinética
14.
Front Cell Infect Microbiol ; 13: 1139436, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968119

RESUMO

Background: Recent studies reported the association between the changes in gut microbiota and sepsis, but there is unclear for the gut microbes on aged sepsis is associated acute lung injury (SALI), and metformin treatment for the change in gut microbiota. This study aimed to investigate the effect of metformin on gut microbiota and SALI in aged rats with sepsis. It also explored the therapeutic mechanism and the effect of metformin on aged rats with SALI. Methods: Aged 20-21 months SD rats were categorized into three groups: sham-operated rats (AgS group), rats with cecal ligation and puncture (CLP)-induced sepsis (AgCLP group), and rats treated with metformin (100 mg/kg) orally 1 h after CLP treatment (AgMET group). We collected feces from rats and analyzed them by 16S rRNA sequencing. Further, the lung samples were collected for histological analysis and quantitative real-time PCR (qPCR) assay and so on. Results: This study showed that some pathological changes occurring in the lungs of aged rats, such as hemorrhage, edema, and inflammation, improved after metformin treatment; the number of hepatocyte death increased in the AgCLP group, and decreased in the AgMET group. Moreover, metformin relieved SALI inflammation and damage. Importantly, the gut microbiota composition among the three groups in aged SALI rats was different. In particular, the proportion of E. coli and K. pneumoniae was higher in AgCLP group rats than AgS group rats and AgMET group rats; while metformin could increase the proportion of Firmicutes, Lactobacillus, Ruminococcus_1 and Lactobacillus_johnsonii in aged SALI rats. Moreover, Prevotella_9, Klebsiella and Escherichia_Shigella were correlated positively with the inflammatory factor IL-1 in the lung tissues; Firmicutes was correlated negatively with the inflammatory factor IL-1 and IL-6 in the lung tissues. Conclusions: Our findings suggested that metformin could improve SALI and gut microbiota in aged rats, which could provide a potential therapeutic treatment for SALI in aged sepsis.


Assuntos
Lesão Pulmonar Aguda , Microbioma Gastrointestinal , Metformina , Sepse , Ratos , Animais , Metformina/farmacologia , Metformina/uso terapêutico , Ratos Sprague-Dawley , RNA Ribossômico 16S/genética , Escherichia coli/genética , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/patologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/patologia , Pulmão/patologia , Inflamação/patologia , Interleucina-1/farmacologia , Interleucina-1/uso terapêutico
15.
Materials (Basel) ; 16(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36837362

RESUMO

In this paper, micro-size spherical silver particles were prepared by using a wet-chemical reduction method. The silver particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and a laser particle-size analyzer. The results indicate that different types and the content of surfactants can be used to prevent the accumulation, and control the morphology and particle size distribution, of silver particles. Moreover, the morphology of silver particles was changed from polyhedral to spherical when the pH was raised from 1 to 3. Under the optimal synthesis conditions (0.1 mol/L silver nitrate, 0.06 mol/L ascorbic acid, gelatin (5% by weight of silver nitrate), pH = 1), the micro-size spherical silver particles with diameter of 5-8 µm were obtained. In addition, the resistivity of conductive silver paste that prepared with the as-synthesized spherical silver particles was discussed in detail and the average resistivity of the conductive silver paste was 3.57 × 10-5 Ω·cm after sintering at 140 °C for 30 min.

16.
Funct Integr Genomics ; 23(1): 60, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790562

RESUMO

Xenotransplantation with porcine organs has been recognized as a promising solution to alleviate the shortage of organs for human transplantation. Porcine endogenous retrovirus (PERV), whose proviral DNAs are integrated in the genome of all pig breeds, is a main microbiological risk for xenotransplantation. Over the last decades, some advances on PERVs' studies have been achieved. Here, we reviewed the current progress of PERVs including the classification, molecular structure, regulation, function in immune system, and potential risk in xenotransplantation. We also discussed the problem of insufficient study on PERVs as well as the questions need to be answered in the future work.


Assuntos
Retrovirus Endógenos , Suínos , Animais , Humanos , Transplante Heterólogo/efeitos adversos , Retrovirus Endógenos/genética , Estrutura Molecular
17.
Int J Chron Obstruct Pulmon Dis ; 17: 1921-1928, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36039167

RESUMO

Purpose: To develop a potential quadriceps' index of complication evaluation for patients with chronic obstructive pulmonary disease (COPD) which is simple, convenient, and quantifiable. Patients and Methods: We conducted a prospective study of 59 patients with COPD and 56 healthy controls recruited by the Chengdu First People's Hospital. Grayscale ultrasound (US) of the rectus femoris was performed to measure thickness (RFthick) and cross-sectional area (RFcsa). Shear wave elastography was used to determine the mean elasticity index (SWEmean) of the rectus femoris (SWERFmean), vastus lateralis (SWEVLmean) and vastus medialis (SWEVMmean). Clinical features included dyspnea index score (modified British Medical Research Council (MMRC) score), COPD Assessment Test (CAT), the Five-Repetition Sit-to-Stand Test (5STS) and the Six-Minute Walk Test (6MWT). We compared the differences between US parameters and SWEmean in healthy controls and COPD patients. We also described the correlation between US parameters, SWEmean and clinical features of patients with COPD. Results: The intra-observer repeatability for the performance of using SWE to measure quadriceps stiffness was excellent (intraclass correlation coefficient (ICC)>0.75, p < 0.001). There was a statistically significant difference in the SWEmean of the quadriceps (p < 0.001), but no significant difference in terms of RFthic and RFcsa (p > 0.05) between healthy controls and COPD patients. The SWERFmean was positively correlated with the 6MWT (r = 0.959, p < 0.001), and negatively related to the mMRC (r=-0.825, p < 0.001), CAT (r=-0.993, p < 0.001) and 5STS (r=-0.936, p < 0.001). However, the RFthic, RFcsa, SWEVLmean and SWEVMmean were not correlated with clinical features (p > 0.05). Conclusion: As a supplement to US, SWE reflects changes of stiffness in the quadriceps of COPD patients, and can expanding the dimension of US for assessing the quadriceps. Furthermore, SWEmean was associated with clinical features, and represents a potential index with which to reflect the clinical features of COPD patients.


Assuntos
Técnicas de Imagem por Elasticidade , Doença Pulmonar Obstrutiva Crônica , Humanos , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Músculo Quadríceps/diagnóstico por imagem , Teste de Caminhada
18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(2): 257-266, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35523546

RESUMO

The research shows that personality assessment can be achieved by regression model based on electroencephalogram (EEG). Most of existing researches use event-related potential or power spectral density for personality assessment, which can only represent the brain information of a single region. But some research shows that human cognition is more dependent on the interaction of brain regions. In addition, due to the distribution difference of EEG features among subjects, the trained regression model can not get accurate results of cross subject personality assessment. In order to solve the problem, this research proposes a personality assessment method based on EEG functional connectivity and domain adaption. This research collected EEG data from 45 normal people under different emotional pictures (positive, negative and neutral). Firstly, the coherence of 59 channels in 5 frequency bands was taken as the original feature set. Then the feature-based domain adaptation was used to map the feature to a new feature space. It can reduce the distribution difference between training and test set in the new feature space, so as to reduce the distribution difference between subjects. Finally, the support vector regression model was trained and tested based on the transformed feature set by leave-one-out cross-validation. What's more, this paper compared the methods used in previous researches. The results showed that the method proposed in this paper improved the performance of regression model and obtained better personality assessment results. This research provides a new method for personality assessment.


Assuntos
Algoritmos , Eletroencefalografia , Encéfalo , Eletroencefalografia/métodos , Emoções , Humanos , Determinação da Personalidade
19.
Artigo em Inglês | MEDLINE | ID: mdl-34986098

RESUMO

Cognitive workload recognition is pivotal to maintain the operator's health and prevent accidents in the human-robot interaction condition. So far, the focus of workload research is mostly restricted to a single task, yet cross-task cognitive workload recognition has remained a challenge. Furthermore, when extending to a new workload condition, the discrepancy of electroencephalogram (EEG) signals across various cognitive tasks limits the generalization of the existed model. To tackle this problem, we propose to construct the EEG-based cross-task cognitive workload recognition models using domain adaptation methods in a leave-one-task-out cross-validation setting, where we view any task of each subject as a domain. Specifically, we first design a fine-grained workload paradigm including working memory and mathematic addition tasks. Then, we explore four domain adaptation methods to bridge the discrepancy between the two different tasks. Finally, based on the supporting vector machine classifier, we conduct experiments to classify the low and high workload levels on a private EEG dataset. Experimental results demonstrate that our proposed task transfer framework outperforms the non-transfer classifier with improvements of 3% to 8% in terms of mean accuracy, and the transfer joint matching (TJM) consistently achieves the best performance.


Assuntos
Eletroencefalografia , Máquina de Vetores de Suporte , Cognição , Eletroencefalografia/métodos , Humanos , Reconhecimento Psicológico , Carga de Trabalho
20.
RSC Adv ; 11(18): 10922-10928, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35423586

RESUMO

Detection of carcinogens is generally recognized to be meaningful, especially for nitrites (NO2 -). Here blue-green fluorescent carbon dots (CDs) were successfully synthesized by using p-aminobenzenesulfonic acid, and their surfaces were identified to be abundant in the functional groups of amino, hydroxyl, and sulfuric acid. Importantly, the sulfuric acid group and aromatic primary ammonia groups on the surfaces of CDs showed the interactions with the nitrites to cause fluorescence quenching. The novel CDs showed high sensitivity and selectivity for NO2 - detection with a low detection limit of 0.03 mM in water due to the fluorescence quenching effect of the CDs. Consequently, the proposed CDs here may provide a new way of monitoring NO2 - in the target samples.

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