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1.
Bioorg Chem ; 149: 107492, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38820939

RESUMO

As a member of glycosyltransferases, fucosyltransferase 8 (FUT8) is essential to core fucosylation and has been considered as a potential therapeutic target for malignant tumors, including colorectal cancer (CRC). Based on the identification of key binding residues and probable conformation of FUT8, an integrated strategy that combines virtual screening and chemical optimization was carried out and compound 15 was identified as a potent FUT8 inhibitor with novel chemical structure and in vitro antitumor activity. Moreover, chemical pulldown experiments and binding assays confirmed that compound 15 selectively bound to FUT8. In vivo, compound 15 showed promising anti-CRC effects in SW480 xenografts. These data support that compound 15 is a potential FUT8 inhibitor for CRC treatment and deserve further optimization studies.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Descoberta de Drogas , Inibidores Enzimáticos , Fucosiltransferases , Fucosiltransferases/antagonistas & inibidores , Fucosiltransferases/metabolismo , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Animais , Relação Estrutura-Atividade , Camundongos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Relação Dose-Resposta a Droga , Proliferação de Células/efeitos dos fármacos , Camundongos Nus , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Neoplasias Experimentais/metabolismo , Simulação de Acoplamento Molecular
2.
Exp Eye Res ; 232: 109509, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37247833

RESUMO

In this study, we explored the predictive role of choroidal blood perfusion (ChBP) and choroidal thickness (ChT) on the development of myopia in guinea pigs. Optical Coherence Tomography Angiography (OCTA) was used to assess the baseline choroidal blood perfusion (ChBP) and choroidal thickness (ChT) in 4-week-old guinea pigs. Refraction and axial length (AL) were measured at baseline. Myopia was induced for one week using form-deprivation (FD) or negative lenses followed by measurements of refraction, axial length and choroidal parameters (ChT and ChBP). The correlations were evaluated between the baseline choroidal values and the magnitude of myopia induced, along with the magnitude of changes in ChT and ChBP after myopia induction. There was a significant correlation between the baseline choroidal parameters and ocular refraction. Myopia induction led to choroidal thinning and less ChBP as well as longer eyes. On the other hand, following exposure to the same non-obstructed visual induction period, the myopic shift was less, and it was associated with thicker choroids and more ChBP at baseline. One week of myopia induction also resulted in thinner choroids and less ChBP, and these declines also correlated with their baseline values. In conclusion, the present study shows that the changes in the baseline choroidal ChT and ChBP parameters are proportional to the magnitude of myopia development and axial elongation in guinea pigs. These significant correlations between baseline ChBP and ChT and myopia development suggest that they may be a viable predictor of this process in guinea pigs.


Assuntos
Miopia , Cobaias , Animais , Miopia/diagnóstico , Refração Ocular , Corioide/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Perfusão
3.
BMC Oral Health ; 23(1): 738, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817146

RESUMO

BACKGROUND: Double teeth are usually the result of an abnormality in the developing tooth germ. Double teeth can occur in either the primary or permanent dentition, with the majority of cases concerning permanent teeth reported in the anterior teeth and less frequently in the molar teeth. CASE PRESENTATION: This report illustrates five cases of double teeth in molars with pulp and periapical disease, including one case of geminated teeth and four cases of fused teeth. Radiographic findings revealed the presence of extra teeth on the buccal aspect of the molar in five cases, with or without communication between the two root canal systems. Root canal treatment was performed by using CBCT and a dental operating microscope. The treatment outcome was good in all five cases. CONCLUSION: The diagnosis and treatment of double teeth requires special attention. The root canal system should be carefully explored to obtain a full understanding of the anatomy, allowing it to be fully cleaned and obturated. Proper anatomical structure analysis prior to treatment facilitates the development of an appropriate treatment plan, thereby increasing the likelihood of successful treatment both aesthetically and functionally.


Assuntos
Dentes Fusionados , Doenças Periapicais , Humanos , Cavidade Pulpar/anatomia & histologia , Tratamento Conservador , Dente Molar/anatomia & histologia , Doenças Periapicais/diagnóstico por imagem , Doenças Periapicais/terapia , Tomografia Computadorizada de Feixe Cônico/métodos , Raiz Dentária
4.
Oncology ; 100(5): 290-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35350032

RESUMO

PURPOSE: Nonampullary duodenal adenocarcinoma (NADA) is a rare disease. Although several prognostic factors have been reported for this disease, they remain controversial due to their rarity. In this study, we retrospectively analyzed 54 cases of invasive NADA, focusing on the microsatellite instability (MSI) phenotype, programmed cell death-ligand 1 (PD-L1) expression, and prognostic factors. METHODS: Expression of the PD-L1 protein and cell differentiation markers in tumors was detected by immunohistochemistry. Microsatellite markers (NR-21, NR-22, NR-24, BAT-25, and BAT-26) were amplified for MSI assessment by PCR. RESULTS: The incidence of MSI in invasive NADA was 35.2%. No significant correlation between the MSI phenotype and clinicopathological factors was observed. Positive expression of PD-L1 by immune cells was common in advanced-stage disease (p = 0.054), and positive expression of PD-L1 in cancer cells correlated significantly with the histologically undifferentiated type (p = 0.016). Kaplan-Meier survival analysis demonstrated a significantly better overall survival (OS) in patients with MSI (p = 0.013) and at early-stage disease (p = 0.000) than in those with microsatellite-stable or at late tumor stages. Univariate and multivariate analyses showed that MSI (hazard ratio [HR]: 0.282, 95% confidence interval [CI]: 0.106-0.751, p = 0.011) and early tumor stage (stage I-II) (HR: 8.81, 95% CI: 2.545-30.500, p = 0.001) were independent better prognostic factors of OS. CONCLUSIONS: MSI and early tumor stage (stage I-II) were independent better prognostic factors of OS. A high proportion of MSI phenotypes and positive PD-L1 expression may be helpful for identifying immune checkpoint inhibitors as a novel therapeutic strategy.


Assuntos
Adenocarcinoma , Instabilidade de Microssatélites , Adenocarcinoma/genética , Adenocarcinoma/patologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Humanos , Prognóstico , Estudos Retrospectivos
5.
Financ Res Lett ; 46: 102372, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35431676

RESUMO

Anecdotal evidence seems to suggest that the initial public offering (IPO) market performed remarkably well through the COVID-19 pandemic. To further understand this peculiar observation, we carry out a comprehensive analysis of IPOs during the pandemic vis-a-vis IPOs before the pandemic. Our findings imply that IPOs during the pandemic experience greater information uncertainty compared to those before the pandemic, and this greater uncertainty is mainly driven by the IPOs from the high-technology and the healthcare sectors. Furthermore, we find that an average IPO firm experiences larger underpricing and more post-IPO return volatility as the pandemic and the associated government responses increase in severity before the offering. Overall, our study indicates that the COVID-19 pandemic had an adverse impact on the IPO market.

6.
Anal Chem ; 93(33): 11547-11556, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34374521

RESUMO

The subcellular distribution of adenosine 5'-triphosphate (ATP) and the concentration of ATP in living cells dynamically fluctuate with time during different cell cycles. The dictated activation of the biosensing process in living cells enables the spatiotemporal target detection in single living cells. Herein, a kind of o-nitrobenzylphosphate ester hairpin nucleic acid was introduced as a photoresponsive DNA probe for light-activated ATP detection in single living cells. Two methods to spatiotemporally activate the probe in single living cells were discussed. One method was the usage of the micrometer-sized optical fiber (about 5 µm) to guide the UV light (λ = 365 nm) to selectively activate the photoresponsive DNA probe in single living cells. The second method involved a two-photon laser confocal scanning microscope to selectively irradiate the photoresponsive DNA probes confined in single living cells via two-photon irradiation (λ = 740 nm). ATP aptamer integrated in the activated DNA probes selectively interacted with the target ATP, resulting in dictated signal generation. Furthermore, the photoactivated biosensing process enables dictated dual-model ATP detection in single living cells with "Signal-ON" fluorescence signal and "Signal-OFF" electrochemical signal outputs. The developed photoactivated biosensor for dictated ATP detection with high spatiotemporal resolution in single living cells at a desired time and desired place suggests the possibility to monitor biomarkers during different cell cycles.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Trifosfato de Adenosina , DNA , Sondas de DNA
7.
Anal Chem ; 93(48): 16264-16272, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34797071

RESUMO

Specific and sensitive detection and imaging of cancer-related miRNA in living cells are desirable for cancer diagnosis and treatment. Because of the spatiotemporal variability of miRNA expression level during different cell cycles, signal amplification strategies that can be activated by external stimuli are required to image miRNAs on demand at desired times and selected locations. Herein, we develop a signal amplification strategy termed as the photoactivated DNA walker based on DNA nanoflares, which enables photocontrollable signal amplification imaging of cancer-related miRNA in single living cells. The developed method is achieved via combining photoactivated nucleic acid displacement reaction with the traditional exonuclease III (EXO III)-assisted DNA walker based on DNA nanoflares. This method is capable of on-demand activation of the DNA walker for dictated signal amplification imaging of cancer-related miRNA in single living cells. The developed method was demonstrated as a proof of concept to achieve photoactivated signal amplification imaging of miRNA-21 in single living HeLa cells via selective two-photon irradiation (λ = 740 nm) of single living HeLa cells by using confocal microscopy equipped with a femtosecond laser.


Assuntos
Técnicas Biossensoriais , MicroRNAs , DNA/genética , Células HeLa , Humanos , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico
8.
Sensors (Basel) ; 20(16)2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32824389

RESUMO

This study examined how users acquire spatial knowledge in an onscreen three-dimensional virtual environment when using overview maps. This experiment adopted a three (the size of overview maps) x two (the transparency of overview maps) between-subjects design. Three levels of the size of overview maps were evaluated, i.e., 1/2, 1/8, and 1/16 screen size. Comparisons between 20% transparent and 80% transparent were made. We asked 108 participants to complete spatial perception tasks and fill out questionnaires regarding their feelings. The results indicate the following: (1) The effects of the transparency of overview maps on users' spatial perception vary with the size of overview maps. The 80% transparent overview map is significantly more efficient than the 20% transparent overview map in the condition of 1/2 screen size. However, the result is opposite in the condition of 1/8 screen size. (2) Users like the 80% transparent overview map significantly better than the 20% transparent overview map in the condition of 1/2 screen size. (3) Concerning subjective evaluations of satisfaction, preference, and system usability, overview maps in the condition of 1/8 screen size are significantly better than those in the condition of 1/2 screen size.

9.
Reprod Biol Endocrinol ; 16(1): 74, 2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30086781

RESUMO

BACKGROUND: Pregnancies following assisted reproductive technology (ART) may have elevated potential risk of pregnancy loss (PL) when compared to natural conception. However, rare studies comprehensively analyzed the IVF/ICSI cycle-dependent factors for loss of clinical pregnancy. Therefore, we aimed to determine the ART subgroup-specific risks of PL throughout pregnancy and explore different risk factors for early miscarriage and late miscarriage among pregnancies conceived through ART. METHODS: A retrospective cohort study was launched in two infertility treatment centers in Nanjing and Changzhou including 5485 IVF/ICSI embryo transfer cycles with known outcomes after clinical pregnancy by the end of 2015. Cox proportional hazards regression analysis was performed to estimate the hazard ratios and their 95% confidence intervals. The associations between survival time during pregnancy and demographics and clinical characteristics of clinical pregnancies were estimated using the Kaplan-Meier method and the Log-rank test. RESULTS: The overall PL rate in current ART population was 12.5%. Among the 685 pregnancy loss cycles, a total of 460 ended as early miscarriage, 191 as late miscarriage. We found couples in ART pregnancies demonstrated a significantly increased risk of PL as maternal age (HR = 1.31, Ptrend < 0.001) grows. Pregnancies received controlled ovarian hyperstimulation (COH) protocol like GnRH antagonist protocol (HR = 3.49, P < 0.001) and minimal stimulation protocol (HR = 1.83, P < 0.001) had higher risk of PL than GnRH-a long protocol. Notably, in contrast to fresh cycle, women who received frozen cycle embryo had a significant increased risk of early miscarriage (P < 0.001), while frozen cycle was linked with lower risk of late miscarriage (P = 0.045). In addition, four factors (maternal age, COH protocol, cycle type and serum hCG level 14 days after transfer) had independent impact on miscarriage mainly before 12 weeks of gestational age. CONCLUSIONS: With these findings in this study, clinicians may make it better to evaluate a patient's risk of PL based on the maternal age at the time of treatment, COH protocol, cycle type and serum hCG level 14 days after transfer and the gestational week of the fetus, and we hope that it contributes to future study on its etiology and guide the clinical prevention and treatment.


Assuntos
Aborto Espontâneo/etiologia , Fertilização in vitro/efeitos adversos , Técnicas de Reprodução Assistida/efeitos adversos , Medição de Risco/métodos , Adulto , Feminino , Humanos , Nascido Vivo , Gravidez , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco/estatística & dados numéricos , Fatores de Risco
10.
Int J Cancer ; 141(5): 958-966, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28510306

RESUMO

It has been proposed that the majority of disease-associated loci identified by genome-wide association studies (GWAS) are enriched in non-coding regions, such as the promoter, enhancer or non-coding RNA genes. Thus, we performed a two-stage case-control study to systematically evaluate the association of genetic variants in miRNA regulatory regions (promoter and enhancer) with lung cancer risk in 7,763 subjects (discovery stage: 2,331 cases and 3,077 controls; validation stage: 1,065 cases and 1,290 controls). As a result, we identified that rs12740674 (C > T) in miR-1262 enhancer was significantly associated with the increased risk of lung cancer (additive model in discovery stage: adjusted OR = 1.31, 95%CI = 1.13-1.53, p = 3.846 × 10-4 in Nanjing GWAS; adjusted OR = 1.20, 95%CI = 1.00-1.44, p = 0.041 in Beijing GWAS; validation stage: adjusted OR = 1.20, 95%CI = 1.03-1.41, p = 0.024). In meta-analysis, the p value for the association between rs12740674 and lung cancer risk reached 6.204 × 10-6 (adjusted OR = 1.24, 95%CI = 1.13-1.36). Using 3DSNP database, The Cancer Genome Atlas (TCGA) data and functional assays, we observed that the risk T allele of rs12740674 reduced the expression level of miR-1262 in lung tissue through chromosomal looping, and overexpression of miR-1262 inhibited lung cancer cell proliferation probably through targeting the expression levels of ULK1 and RAB3D. Our findings confirmed the important role that genetic variants of noncoding sequence play in lung cancer susceptibility and indicated that rs12740674 in miR-1262 may be biologically relevant to lung carcinogenesis.


Assuntos
Predisposição Genética para Doença/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase em Tempo Real , Sequências Reguladoras de Ácido Nucleico/genética
11.
Sci Data ; 11(1): 671, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909027

RESUMO

Accurate cropland map serves as the cornerstone of effective agricultural monitoring. Despite the continuous enrichment of remotely sensed cropland maps, pervasive inconsistencies have impeded their further application. This issue is particularly evident in areas with limited valid observations, such as southwestern China, which is characterized by its complex topography and fragmented parcels. In this study, we constructed multi-sourced samples independent of the data producers, taking advantage of open-source validation datasets and sampling to rectify the accuracy of ten contemporary cropland maps in southwestern China, decoded their inconsistencies, and generated a refined cropland map (CroplandSyn) by leveraging ten state-of-the-art remotely sensed cropland maps released from 2021 onwards using the self-adaptive threshold method. Validations, conducted at both prefecture and county scales, underscored the superiority of the refined cropland map, aligning more closely with national land survey data. The refined cropland map and samples are publicly available to users. Our study offers valuable insights for improving agricultural practices and land management in under-monitored areas by providing high-quality cropland maps and validation datasets.

12.
Anal Methods ; 16(20): 3179-3191, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38738644

RESUMO

Extracellular vesicles (EVs) are nanoparticles secreted by cells with a closed phospholipid bilayer structure, which can participate in various physiological and pathological processes and have significant clinical value in disease diagnosis, targeted therapy and prognosis assessment. EV isolation methods currently include differential ultracentrifugation, ultrafiltration, size exclusion chromatography, immunoaffinity, polymer co-precipitation and microfluidics. In addition, material-based biochemical or biophysical approaches relying on intrinsic properties of the material or its surface-modified functionalized monomers, demonstrated unique advantages in the efficient isolation of EVs. In order to provide new ideas for the subsequent development of material-based EV isolation methods, this review will focus on the principle, research status and application prospects of material-based EV isolation methods based on different material carriers and functional monomers.


Assuntos
Vesículas Extracelulares , Ultracentrifugação , Vesículas Extracelulares/química , Humanos , Ultracentrifugação/métodos , Cromatografia em Gel/métodos , Animais , Ultrafiltração/métodos
13.
Biofabrication ; 16(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38198708

RESUMO

Three-dimensional (3D) bioprinting embedded within a microgel bath has emerged as a promising strategy for creating intricate biomimetic scaffolds. However, it remains a great challenge to construct tissue-scale structures with high resolution by using embedded 3D bioprinting due to the large particle size and polydispersity of the microgel medium, as well as its limited cytocompatibility. To address these issues, novel uniform sub-microgels of cell-friendly cationic-crosslinked kappa-carrageenan (κ-Car) are developed through an easy-to-operate mechanical grinding strategy. Theseκ-Car sub-microgels maintain a uniform submicron size of around 642 nm and display a rapid jamming-unjamming transition within 5 s, along with excellent shear-thinning and self-healing properties, which are critical for the high resolution and fidelity in the construction of tissue architecture via embedded 3D bioprinting. Utilizing this new sub-microgel medium, various intricate 3D tissue and organ structures, including the heart, lungs, trachea, branched vasculature, kidney, auricle, nose, and liver, are successfully fabricated with delicate fine structures and high shape fidelity. Moreover, the bone marrow mesenchymal stem cells encapsulated within the printed constructs exhibit remarkable viability exceeding 92.1% and robust growth. Thisκ-Car sub-microgel medium offers an innovative avenue for achieving high-quality embedded bioprinting, facilitating the fabrication of functional biological constructs with biomimetic structural organizations.


Assuntos
Bioimpressão , Microgéis , Carragenina , Bioimpressão/métodos , Alicerces Teciduais/química , Hidrogéis/química , Cátions , Impressão Tridimensional , Engenharia Tecidual/métodos
14.
Nat Commun ; 15(1): 4106, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750031

RESUMO

China's extensive planted forests play a crucial role in carbon storage, vital for climate change mitigation. However, the complex spatiotemporal dynamics of China's planted forest area and its carbon storage remain uncaptured. Here we reveal such changes in China's planted forests from 1990 to 2020 using satellite and field data. Results show a doubling of planted forest area, a trend that intensified post-2000. These changes lead to China's planted forest carbon storage increasing from 675.6 ± 12.5 Tg C in 1990 to 1,873.1 ± 16.2 Tg C in 2020, with an average rate of ~ 40 Tg C yr-1. The area expansion of planted forests contributed ~ 53% (637.2 ± 5.4 Tg C) of the total above increased carbon storage in planted forests compared with planted forest growth. This proactive policy-driven expansion of planted forests has catalyzed a swift increase in carbon storage, aligning with China's Carbon Neutrality Target for 2060.

15.
Behav Sci (Basel) ; 13(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37504007

RESUMO

This paper used the mixed research method of bibliometric and content analysis to study 284 studies on service robots in the tourism and hospitality industry collected from the Web of Science database. Results show that research in this field started late, and that the COVID-19 pandemic has promoted the rapid growth of the number of research papers. The International Journal of Contemporary Hospitality Management has so far published the most number of papers. Numerous scholars from universities in different regions of the world have made significant contributions to the research of service robots, and academic collaborations are relatively common, but there are only very few high-yield authors. Empirical research has been widely favored by researchers, wherein online questionnaire and experimental methods have been frequently used. Multidisciplinary theories have also been cited in related articles, especially on the applications of psychological theories. The research fronts cover four branches focusing on service robots, consumers, human employees, and service environment, with all four parts largely overlapping in content. Finally, the paper discusses prospects for the future research agenda of service robots in the tourism and hospitality industry.

16.
Heliyon ; 9(7): e18241, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37519669

RESUMO

An ectopic pancreas is defined as pancreatic tissue outside its normal location, anatomically separated from the pancreas. The transcription factor pancreas/duodenum homeobox protein 1 (PDX1) is involved in maintaining the pancreas and functions in early pancreatic development, beta cell differentiation, and endocrine non beta cells. Pancreatic transcription factor 1 subunit alpha (PTF1A) affects exocrine cell formation and regulation of acinar cell identity, and is expressed in exocrine cells as a transcription factor. The depletion of SALL4 disrupts self-renewal and induces differentiation. To clarify which of PDX1, PTF1A, or SALL4 determines the difference in Heinrich's classification, we examined the localization and number of positive cells. We analyzed the differential expression of PDX1, PTF1A, and SALL4 in large and small ducts in ectopic pancreas by immunohistochemistry. Results showed that the number of PTF1A-positive cells in large ducts was more widespread in type I than in type II in the gastro-duodenum, and more SALL4-positive cells were noticed in large ducts than in small ducts in the gastro-duodenum of type II. Our results revealed that PTF1A might promote exocrine differentiation in developing the pancreatic tissues, and that those with widespread expression differentiate into exocrine cells.

17.
Anal Chim Acta ; 1269: 341426, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37290854

RESUMO

Two-dimensional (2D) materials such as MXenes, are usually well utilized in the field of catalysts and battery due to their good hydrophilicity and diversified surface terminals. However, their potential applications in the treatment of biological samples have not been widely concerned. Extracellular vesicles (EVs) contain unique molecular signatures and could be used as biomarkers for the detection of severe diseases such as cancer, as well as monitoring the therapeutic response. In this work, two kinds of MXene materials (Ti3C2 and Ti2C) were successfully synthesized and employed in the isolation of EVs from the biological samples by taking advantage of the affinity interaction between the titanium (Ti) in MXenes and the phospholipid membrane of EVs. Compared with Ti2C MXene materials, TiO2 beads and the other EVs isolation methods, Ti3C2 MXene materials exhibited excellent isolation performance via the coprecipitation with EVs due to the abundant unsaturated coordination of Ti2+/Ti3+, and the dosage of materials was the lowest. Meanwhile, the whole isolation process could be done within 30 min and integrated well with the following analysis of proteins and ribonucleic acids (RNAs), which was also convenient and economic. Furthermore, the Ti3C2 MXene materials were used to isolate the EVs from the blood plasma of colorectal cancer (CRC) patients and healthy donors. Proteomics analysis of EVs showed that 67 proteins were up-regulated, in which most of them were closely related to CRC progression. These findings indicate that the MXene material-based EVs isolation method via coprecipitation provides an efficient tool for early diagnosis of diseases.


Assuntos
Neoplasias , Titânio , Humanos
18.
Structure ; 31(12): 1604-1615.e8, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37794595

RESUMO

4-Hydroxyphenylpyruvate dioxygenase (HPPD) has attracted increasing attention as a target for treating type I tyrosinemia and other diseases with defects in tyrosine catabolism. Only one commercial drug, 2-(2-nitro-4-trifluoromethylbenzoyl)-1, 3-cyclohexanedione (NTBC), clinically treat type I tyrosinemia, but show some severe side effects in clinical application. Here, we determined the structure of human HPPD-NTBC complex, and developed new pyrazole-benzothiadiazole 2,2-dioxide hybrids from the binding of NTBC. These compounds showed improved inhibition against human HPPD, among which compound a10 was the most active candidate. The Absorption Distribution Metabolism Excretion Toxicity (ADMET) predicted properties suggested that a10 had good druggability, and was with lower toxicity than NTBC. The structure comparison between inhibitor-bound and ligand-free form human HPPD showed a large conformational change of the C-terminal helix. Furthermore, the loop 1 and α7 helix were found adopting different conformations to assist the gating of the cavity, which explains the gating mechanism of human HPPD.


Assuntos
Herbicidas , Tiadiazóis , Tirosinemias , Humanos , Tirosinemias/tratamento farmacológico , Tiadiazóis/farmacologia , Tiadiazóis/uso terapêutico , Pirazóis/farmacologia , Inibidores Enzimáticos/farmacologia
19.
Anal Chim Acta ; 1279: 341785, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827681

RESUMO

Extracellular vesicles (EVs) are important participants in numerous pathophysiological processes, and could be used as valuable biomarkers to detect and monitor various diseases. However, facile EV isolation methods are the essential and preliminary issue for their downstream analysis and function investigation. In this work, a polyhedral oligomeric silsesquioxanes (POSS) based hybrid monolith combined metal affinity chromatography (MAC) and distearoyl phospholipid ethanolamine (DSPE) function was developed via photo-initiated thiol-ene polymerization. This synthesis process was facile, simple and convenient, and the obtained hybrid monolith could be applied to efficiently isolate EVs from bio-samples by taking advantages of the specific bond of Ti4+ and phosphate groups on the phospholipid membrane of EVs and the synergistic effect of DSPE insertion. Meanwhile, the eluted EVs could maintain their structural integrity and biological activity, suggesting they could be used for downstream application. Furthermore, 75 up-regulated proteins and 56 down-regulated proteins were identified by comparing the urinary EVs of colorectal cancer (CRC) patients and healthy donors, and these proteins might be used as potential biomarkers for early screening of CRC. These results demonstrated that this hybrid monolith could be used as a simple and convenient tool for isolating EVs from bio-samples and for wider applications in biomarker discovery.


Assuntos
Vesículas Extracelulares , Compostos de Organossilício , Humanos , Compostos de Organossilício/química , Polimerização , Interações Hidrofóbicas e Hidrofílicas , Biomarcadores , Fosfolipídeos
20.
J Agric Food Chem ; 71(49): 19396-19407, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38035573

RESUMO

Plant pathogenic fungi pose a significant threat to crop yields and quality, and the emergence of fungicide resistance has further exacerbated the problem in agriculture. Therefore, there is an urgent need for efficient and environmentally friendly fungicides. In this study, we investigated the antifungal activity of (+)-Usnic acid and its inhibitory effect on crop pathogenic fungal 4-hydroxyphenylpyruvate dioxygenases (HPPDs) and determined the structure of Zymoseptoria tritici HPPD (ZtHPPD)-(+)-Usnic acid complex. Thus, the antifungal target of (+)-Usnic acid and its inhibitory basis toward HPPD were uncovered. Additionally, we discovered a potential lead fungicide possessing a novel scaffold that displayed remarkable antifungal activities. Furthermore, our molecular docking analysis revealed the unique binding mode of this compound with ZtHPPD, explaining its high inhibitory effect. We concluded that HPPD represents a promising target for the control of phytopathogenic fungi, and the new compound serves as a novel starting point for the development of fungicides and dual-purpose pesticides.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase , Fungicidas Industriais , Herbicidas , Fungicidas Industriais/farmacologia , 4-Hidroxifenilpiruvato Dioxigenase/química , Herbicidas/química , Antifúngicos/farmacologia , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Relação Estrutura-Atividade
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