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1.
BMC Cardiovasc Disord ; 24(1): 43, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218809

RESUMO

BACKGROUND: Cardiac masses can encompass a variety of conditions, such as tumors, thrombi, vegetations, calcific lesions, and other rare diseases. Treatment and management of these types of cardiac masses differ considerably. Thus, accurately distinguishing among thrombi, benign tumors, and malignant tumors in the heart is of great importance. Contrast echocardiography (CE) has emerged as a promising technology. Although published guidelines suggest that CE can enhance image quality and assist in differentiating between benign and malignant lesions, most studies on CE diagnosis of cardiac masses are limited to case reports or retrospective/small-sample-sized prospective cohorts. This study aims to evaluate the diagnostic accuracy of CE in patients with suspected cardiac masses and address the insufficient evidence for differential diagnosis using CE. METHODS: Between April 2018 and July 2022, a prospective multicenter study was conducted, which included 145 consecutive patients suspected to have cardiac masses based on transthoracic echocardiography. All patients underwent CE examinations. The echocardiographic diagnosis relied on qualitative factors such as echogenicity, boundary, morphology of the base, mass perfusion, pericardial effusion, and motility as well as quantitative factors such as the area of the masses and the peak intensity ratio of the masses to adjacent myocardium (A1/A2). RESULTS: The final confirmed diagnoses were as follows: 2 patients had no cardiac mass, 4 patients had pseudomass, 43 patients had thrombus, 66 patients had benign tumors, and 30 patients had malignant tumors. The receiver operating characteristic (ROC) analysis indicated that an optimal A1/A2 cutoff value of 0.499 distinguished a cardiac tumor from a thrombus, with AUC, sensitivity, specificity, PPV, and NPV of 0.977, 97.9%, 90.7%, 95.9%, and 95.1%, respectively. The optimal A1/A2 cutoff value of 1.583 distinguished a cardiac tumor from a thrombus, with AUC, sensitivity, specificity, PPV, and NPV of 0.950, 93.3%, 93.9%, 87.5%, and 96.9%, respectively. CONCLUSIONS: Combined with qualitative and quantitative analyses, CE has the potential to accurately differentiate among different types of cardiac masses.


Assuntos
Neoplasias Cardíacas , Trombose , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Meios de Contraste , Ecocardiografia/métodos , Neoplasias Cardíacas/diagnóstico por imagem , Diagnóstico Diferencial , Sensibilidade e Especificidade
2.
Sensors (Basel) ; 24(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38610272

RESUMO

Coherent Doppler wind lidar (CDWL) uses transmitted laser pulses to measure wind velocity distribution. However, the echo signal of CDWL is easily affected by atmospheric turbulence, which can decrease the signal-to-noise ratio (SNR) of lidar. To improve the SNR, this paper proposes a pulse accumulation method based on the cross-correlation function to estimate the phase of the signal. Compared with incoherent pulse accumulation, the proposed method significantly enhances the correlation between signals from different periods to obtain high SNR gains that arise from pulse accumulation. Using simulation, the study evaluates the effectiveness of this phase estimation method and its robustness against noise in algorithms which analyze Doppler frequency shifts. Furthermore, a CDWL is developed for measuring the speed of an indoor motor turntable and the outdoor atmospheric wind field. The phase estimation method yielded SNR gains of 28.18 dB and 32.03 dB for accumulation numbers of 500 and 1500, respectively. The implementation of this method in motor turntable speed measurements demonstrated a significant reduction in speed error-averaging 9.18% lower than that of incoherent accumulation lidar systems. In experiments that measure atmospheric wind fields, the linear fit curve slope between the measured wind speed and the wind speed measured via a commercial wind-measuring lidar can be reduced from 1.146 to 1.093.

3.
Anal Chem ; 95(30): 11273-11279, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37478050

RESUMO

Dopamine (DA) is an important neurotransmitter, which not only participates in the regulation of neural processes but also plays critical roles in tumor progression and immunity. However, direct identification of DA-containing exosomes, as well as quantification of DA in single vesicles, is still challenging. Here, we report a nanopipette-assisted method to detect single exosomes and their dopamine contents via amperometric measurement. The resistive-pulse current measured can simultaneously provide accurate information of vesicle translocation and DA contents in single exosomes. Accordingly, DA-containing exosomes secreted from HeLa and PC12 cells under different treatment modes successfully detected the DA encapsulation efficiency and the amount of exosome secretion that distinguish between cell types. Furthermore, a custom machine learning model was constructed to classify the exosome signals from different sources, with an accuracy of more than 99%. Our strategy offers a useful tool for investigating single exosomes and their DA contents, which facilitates the analysis of DA-containing exosomes derived from other untreated or stimulated cells and may open up a new insight to the research of DA biology.

4.
Analyst ; 148(3): 507-511, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36594781

RESUMO

Here, hydrophilic carbon dots (H-CDs) are prepared by a facile room temperature method. The strength of hydrogen bonds can be controlled by introducing proton and aprotic solvents, respectively, so as to realize the tunable aggregation state of H-CDs. Because of the ultrasensitive response to dimethyl sulfoxide (DMSO), H-CDs can serve as optical probes for detecting DMSO in a linear range of 0.005% to 0.75% and with a detection limit of 0.001%.

5.
Eur Spine J ; 32(4): 1345-1357, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36867251

RESUMO

BACKGROUND: Unilateral biportal endoscopic (UBE) has been gradually applied in clinical practice. UBE has two channels, with good visual field and operating space, and has achieved good results in the treatment of lumbar spine diseases. Some scholars combine UBE with vertebral body fusion to replace traditional open fusion surgery and minimally invasive fusion surgery. The efficacy of biportal endoscopic transforaminal lumbar interbody fusion (BE-TLIF) is still controversial. In this systematic review and meta-analysis, BE-TLIF and minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) are compared in the efficacy and complications of lumbar degenerative diseases. METHODS: PubMed, Cochrane Library, Web of Science and China National Knowledge Infrastructure (CNKI) were used to search literatures related to BE-TLIF before January 2023, to identify relevant studies, and systematically review all literatures. Evaluation indicators mainly include operation time, hospital stay, estimated blood loss, visual analog scale (VAS), Oswestry Disability Index (ODI), and Macnab. RESULTS: A total of 9 studies were included in this study; a total of 637 patients were collected, and 710 vertebral bodies were treated. Nine studies showed that there was no significant difference in VAS score, ODI, fusion rate, and complication rate between BE-TLIF and MI-TLIF at the final follow-up after surgery. CONCLUSION: This study suggests that BE-TLIF is a safe and effective surgical approach. BE-TLIF surgery has similar good efficacy to MI-TLIF in the treatment of lumbar degenerative diseases. And compared with MI-TLIF, it has the advantages of early postoperative relief of low-back pain, shorter hospital stay, and faster functional recovery. However, high-quality prospective studies are needed to validate this conclusion.


Assuntos
Vértebras Lombares , Fusão Vertebral , Humanos , Endoscopia/efeitos adversos , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Resultado do Tratamento
6.
Nano Lett ; 22(3): 1338-1344, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35049298

RESUMO

Quasi-2D perovskites, composed of self-organized quantum well structures, are emerging as gain materials for laser applications. Here we investigate the influence of domain distribution on the laser emission of CsPbCl1.5Br1.5-based quasi-2D perovskites. The use of 2,2-diphenylethylammonium bromide (DPEABr) as a ligand enables the formation of quasi-2D film with a large-n-dominated narrow domain distribution. Due to the reduced content of small-n domains, the incomplete energy transfer from small-n to large-n domains can be greatly addressed. Moreover, the photoinduced carriers can be concentrated on most of the large-n domains to reduce the local carrier density, thereby suppressing the Auger recombination. By controlling the domain distribution, we achieve blue amplified spontaneous emission and single-mode vertical-cavity surface-emitting lasing with low thresholds of 6.5 and 9.2 µJ cm-2, respectively. This work provides a guideline to design the domain distribution to realize low-threshold multicolor perovskite lasers.

7.
Environ Monit Assess ; 195(3): 401, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790550

RESUMO

As the Earth's population continuously increase with the passage of time, the demand for agricultural raw material for human need increases. It is critical to maintaining updated and accurate information about the dynamics and properties of the world agricultural systems. As cash crop, the updated information of the spatial distribution of cotton field is necessary to monitor the crop area and growth changes at regional level. We used 8-day enhanced vegetation index (EVI) time series to detect cotton crop area and binomial probabilistic approach to obtain the probability distribution of cotton crop occurrence. We used Gaussian kriging to derive cotton yield inside the detected cotton crop areas through crop reporting data. We also used field data from farmers to validate the cotton yield results. A strong correlation between the MODIS-derived cotton cultivated area and statistical data at the tehsil level were achieved (R2 = 0.84) for all study years (2004-2019). The total accuracy for the cotton crop area detection was 84.6% and yield prediction was 92.1%. Our study presents new approaches to map cotton area and yield, which are applicable to other regions through machine learning.


Assuntos
Tecnologia de Sensoriamento Remoto , Rios , Humanos , Paquistão , Monitoramento Ambiental/métodos , Agricultura/métodos
8.
Angew Chem Int Ed Engl ; 62(49): e202313864, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37812692

RESUMO

Docking of alkali metal ions to water-soluble macrocyclic receptors generally reduces the affinity of guest molecules due to competitive binding. The idea that solvation water molecules could display a larger steric hindrance towards guest binding than cations has not been considered to date. We show that the docking of large cations to cucurbit[5]uril (CB5) unexpectedly increases (by a factor of 5-8) the binding of hydrophobic guests, methane and ethane. This is due to the removal of water molecules from the carbonyl portals of CB5 during cation binding, which frees up space for hydrophobe encapsulation. In contrast, smaller cations like sodium protrude deeply into the cavity of CB5 and cause the expected decrease in binding, such that the rational selection of alkali cations allows for a variation of up to a factor of 20 in binding of methane and ethane. The statistical analysis of crystallographic data shows that the cavity volume of CB5 can be enlarged by placing large alkali ions (Rb+ and Cs+ ) centro-symmetrically at the portals. The results reveal a hitherto elusive steric hindrance of solvation water molecules near receptor binding sites, which is pertinent for the design of supramolecular catalysts and the understanding of biological receptors.

9.
Angew Chem Int Ed Engl ; 62(44): e202311002, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37714815

RESUMO

Artificially performing chemical reactions in living biosystems to attain various physiological aims remains an intriguing but very challenging task. In this study, the Schiff base reaction was conducted in cells using Sc(OTf)3 as a catalyst, enabling the in situ synthesis of a hollow covalent organic polymer (HCOP) without external stimuli. The reversible Schiff base reaction mediated intracellular Oswald ripening endows the HCOP with a spherical, hollow porous structure and a large specific surface area. The intracellularly generated HCOP reduced cellular motility by restraining actin polymerization, which consequently induced mitochondrial deactivation, apoptosis, and necroptosis. The presented intracellular synthesis system inspired by the Schiff base reaction has strong potential to regulate cell fate and biological functions, opening up a new strategic possibility for intervening in cellular behavior.


Assuntos
Polímeros , Bases de Schiff , Bases de Schiff/química
10.
Carcinogenesis ; 43(4): 321-337, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35084494

RESUMO

Numerous papers have reported variants in microRNAs (miRNAs) associated with cancer risk; these results, however, are controversial. We seek to offer an updated, comprehensive synopsis of genetic associations between single nucleotide polymorphisms (SNPs) in miRNAs and cancer risk. We did a systematic field synopsis and meta-analysis to investigate 29 SNPs in 24 miRNAs associated with risk of 18 different kinds of cancer based on data from 247 eligible articles. We graded levels of cumulative epidemiological evidence of significant association using Venice criteria and a false-positive report probability (FPRP) test. We constructed functional annotations for these variants using data from the Encyclopedia of DNA Elements Project. We used FPRP to find additional noteworthy associations between 278 SNPs in 117 miRNAs and risk of 26 cancers based on each SNP with one data source. Sixteen SNPs were statistically associated with risk of 17 cancers. We graded the cumulative epidemiological evidence as strong for statistical associations between 10 SNPs in 8 miRNAs and risk of 11 cancers, moderate for 9 SNPs with 12 cancers and weak for 11 SNPs with 11 cancers. Bioinformatics analysis suggested that the SNPs with strong evidence might fall in putative functional regions. In addition, 38 significant associations were observed in 38 SNPs and risk of 13 cancers. This study offered a comprehensive research on miRNA gene variants and cancer risk and provided referenced information for the genetic predisposition to cancer risk in future research.


Assuntos
MicroRNAs , Neoplasias , Predisposição Genética para Doença , Humanos , MicroRNAs/genética , Neoplasias/epidemiologia , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Risco
11.
J Am Chem Soc ; 144(22): 9747-9752, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35578912

RESUMO

Programmable DNA nanotechnology has generated some of the most intricate self-assembled nanostructures and has been employed in a growing number of applications, including functional nanomaterials, nanofabrication, biophysics, photonics, molecular machines, and drug delivery. An important design rule for DNA nanostructures is to minimize the mechanical stress to reduce the potential energy in these nanostructures whenever it is possible. This work revisits the DNA gridiron design consisting of Holliday junctions and compares the self-assembly of the canonical DNA gridiron with a new design of DNA gridiron, which has a higher degree of mechanical stress because of the interweaving of DNA helices. While the interweaving DNA gridiron indeed exhibits lower yield, compared to its canonical counterpart of a similar size, we discover that the mechanical stress within the interweaving gridiron can promote the formation of the two-dimensional crystalline lattice instead of nanotubes. Furthermore, tuning the design of interweaving gridiron leads to the change of overall crystal size and regularity of geometry. Interweaving DNA double helices represents a new design strategy in the self-assembly of DNA nanostructures. Furthermore, the discovery of the new role of mechanical stress in the self-assembly of DNA nanostructures provides useful knowledge to DNA nanotechnology practitioners: a more balanced view regarding mechanical stress can be considered when designing future DNA nanostructures.


Assuntos
Nanoestruturas , Nanotubos , DNA/química , Nanoestruturas/química , Nanotecnologia/métodos , Conformação de Ácido Nucleico
12.
Ann Surg Oncol ; 29(1): 547-556, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34743281

RESUMO

BACKGROUND: Patient-reported outcomes are critical for obtaining valuable patient insight into different surgical treatment options with comparable clinical outcomes. This study aimed to compare early postoperative patient-reported symptoms and functioning between thoracoscopic segmentectomy and lobectomy for small-sized (≤ 2 cm) peripheral non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: This study included 110 patients who underwent thoracoscopic segmentectomy or lobectomy for peripheral NSCLC ≤ 2 cm in a multicenter prospective longitudinal study (CN-PRO-Lung 1). Symptom severity, functional status, and short-term clinical outcomes were compared between the groups. Symptom severity and functional status were measured using the MD Anderson Symptom Inventory-Lung Cancer at baseline, daily post-surgery, and weekly post-discharge for up to 4 weeks. Both the proportion of moderate-to-severe scores and mean scores on a 0-10 scale were compared between the groups. RESULTS: Overall, 48 and 62 patients underwent thoracoscopic segmentectomy and lobectomy, respectively. No significant between-group differences were found in the severity of the top five symptoms (coughing, shortness of breath, pain, fatigue, and disturbed sleep) or in the impairment of all six function items (work, walking, general activity, enjoyment of life, mood, and relations with others) during both the 6-day postoperative hospitalization and the 4-week post-discharge (all p > 0.05). Short-term clinical outcomes of postoperative hospital stay, operative time, drainage time, postoperative in-hospital oral morphine equivalent dose, and complication rate were also comparable (all p > 0.05). CONCLUSIONS: In patients with peripheral NSCLC ≤ 2 cm, thoracoscopic segmentectomy and lobectomy might produce comparable symptom burden and functional impairment during the early postoperative period.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Assistência ao Convalescente , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Estudos Longitudinais , Neoplasias Pulmonares/cirurgia , Alta do Paciente , Medidas de Resultados Relatados pelo Paciente , Pneumonectomia , Período Pós-Operatório , Estudos Prospectivos
13.
BMC Cancer ; 22(1): 618, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668376

RESUMO

BACKGROUND: Breast cancer and lung cancer are the top two malignancies in the female population and the number of patients with breast cancer and subsequent primary lung cancer has increased significantly in recent years. However, the unique molecular characteristics of this group of patients remains unclear. PURPOSE: To identify the genomic and transcriptome characteristics of primary lung adenocarcinoma patients with previous breast cancer by comparison with single primary lung adenocarcinoma (SPLA) patients. METHODS: The tumor and normal pulmonary tissue specimens of ten primary pulmonary adenocarcinoma patients with previous breast cancer (multiple primary cancer, MPC) and ten SPLA patients were prospectively collected. The whole exome sequencing (WES) and RNA sequencing (RNA-seq) were performed to analyze the gene mutation and expression differences between MPC and SPC patients. RESULTS: The results of WES indicated that the mutations of TRIM73, DLX6 and CNGB1 only existed in MPC patients. The results of RNA-seq manifested the occurrence of second primary lung adenocarcinoma in breast cancer patients was closely associated with cytokine-cytokine receptor action, autophagy, PI3L-Akt, cAMP and calcium ion signaling pathways. Besides, the expression levels of FGF10 and VEGFA genes were significantly increased in MPC patients. CONCLUSION: The occurrence of second primary lung adenocarcinoma may be related to the cytokine-cytokine receptor action, autophagy, PI3L-Akt, cAMP and calcium ion signaling pathways. Furthermore, the mutations of TRIM73, DLX6 and CNGB1 and high expression of FGF10 and VEGFA might play an important role in the development of lung adenocarcinoma in breast cancer patients. However, more in-depth investigations are needed to verify above findings.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias da Mama , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Neoplasias da Mama/genética , Cálcio , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Citocinas/genética , Feminino , Genômica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Citocinas/genética , Transcriptoma
14.
Chemphyschem ; 23(7): e202100833, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35138016

RESUMO

One important prerequisite for the fabrication of molecular functional device strongly relies on the understanding the conducting behaviors of the metal-molecule-metal junction that can respond to an external stimulus. The model Lewis basic molecule 4,4'-(pyridine-3,5-diyl)dibenzonitrile (DBP), which can react with Lewis acid and protic acid, was synthesized. Then, the molecular conducting behavior of DBP, DBP-B(C6 F5 )3 , and DBP-TfOH (DBP-B(C6 F5 )3 , and DBP-TfOH were produced by Lewis acid and protonic acid treatment of DBP) was researched and compared. Given that their identical physical paths for DBP, DBP-B(C6 F5 )3 , and DBP-TfOH to sustain charge transport, our results indicate that modifying the molecular electronic structure, even not directly changing the conductive physical backbone, can tune the charge transporting ability by nearly one order of magnitude. Furthermore, the addition of another Lewis base triethylamine (of stronger alkaline than DBP), to Lewis acid-base pair reverts the electrical properties back to that of a single DBP junction, that is constructive to propose a useful but simple strategy for the design and construction of reversible and controllable molecular device based on pyridine derived molecule.


Assuntos
Eletrônica , Metais , Condutividade Elétrica , Metais/química , Estrutura Molecular
15.
Faraday Discuss ; 233(0): 222-231, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-34889917

RESUMO

Electrochemical (EC) measurements of dynamic nanoparticle collisions on a support electrode provide a powerful approach to study the electrical properties of interfacial molecules self-assembled on the electrode surface. By introducing a special cage-shaped macrocyclic molecule, cucurbit[7]uril (CB7), onto a gold nanoelectrode surface, we show that the dynamic interactions between CB7 and the colliding nanoparticles can be real-time monitored via the appearance of distinct EC current switching signals. When a guest molecule is included in the CB7 cavity, the changed host-guest chemistry can be probed via the amplitude change of the EC current signals. In addition, different guest molecules can be recognized by CB7 on the nanoelectrode surface, giving rise to distinguishable current jump signals for different host-guest systems. Remarkably, two well-defined current states are observed in the EC measurements of the CB7-ferrocene complex, indicating two orientation geometries of ferrocene inside the CB7 cavity can be resolved in this EC sensing platform. This work demonstrates an effective approach for studying the dynamics of host-guest chemistry at the liquid-solid interface and sheds light on a convenient EC sensor for the recognition of target molecules with the aid of CB7.

16.
Environ Sci Technol ; 56(1): 642-651, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34902247

RESUMO

In this work, sulfureted phosphotungstic acid-grafted γ-Fe2O3 (HPW/γ-Fe2O3) was investigated as a regenerable monolithic sorbent to recover gaseous Hg0 upstream of wet flue gas desulfurizations (FGDs), and the effects of HCl, SO2, and H2O on the chemical adsorption of Hg0 onto sulfureted HPW/γ-Fe2O3 were investigated with Hg balance analysis and kinetic analysis. Hg0 conversion over sulfureted HPW/γ-Fe2O3 was remarkably promoted in the presence of HCl, and most Hg0 was catalytically oxidized to HgCl2. Moreover, the chemical adsorption of Hg0 was notably restrained as the key species for Hg0 transformation to HgS (i.e., S22-) was rapidly oxidized by Cl*. However, the effect of HCl on Hg0 conversion over sulfureted HPW/γ-Fe2O3 was almost counteracted by H2O and SO2 as they competed with physically adsorbed Hg0 and S22- for the consumption of Cl*. Therefore, the chemical adsorption of Hg0 onto sulfureted HPW/γ-Fe2O3 in the presence of SO2 and H2O was slightly inhibited by HCl, and only a small amount of HgCl2 was formed. Moreover, sulfureted HPW/γ-Fe2O3 exhibited a moderate ability for gaseous HgCl2 adsorption. As a result, sulfureted HPW/γ-Fe2O3 showed excellent performance in recovering Hg0 from the flue gas upstream of the FGDs for the centralized control of Hg0 emitted from coal-fired plants.


Assuntos
Poluentes Atmosféricos , Mercúrio , Adsorção , Poluentes Atmosféricos/análise , Carvão Mineral , Gases , Cinética , Mercúrio/análise , Centrais Elétricas , Sulfetos , Temperatura
17.
Future Oncol ; 18(2): 163-178, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34677082

RESUMO

Aims: Clarifying the initial trigger of the differentially expressed genes in cancers helps researchers understand the cellular system as a whole network. Materials & methods: We retrieve the transcriptome and translatome of tumor and normal tissues from ten liver cancer patients and define differentially expressed genes and tumor-specific mutations. We associate the oncogenesis with the mutations by target prediction and experimental verification. Results: Upregulated genes have tumor-specific mutations in 3'UTRs that abolish the binding of miRNAs. For downregulated genes, their corresponding miRNAs are mutually targeted by two circRNAs, with mutations in base-pairing regions. Transfection experiments support the oncogenic role of these mutations. Conclusions: The tumor-specific mutations serve as the initial trigger of liver cancer. The mutation-circRNA-miRNA-target gene chain is completed.


Assuntos
Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Neoplasias Hepáticas/genética , Regiões 3' não Traduzidas/genética , Biologia Computacional , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação , RNA Circular/genética , RNA Circular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA-Seq , Regulação para Cima
18.
Appl Opt ; 61(2): 439-445, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35200881

RESUMO

Atmospheric turbulence is an important factor affecting the transmission performance of free-space optical communications (FSOC), especially in the near-surface where the atmospheric turbulence characteristics are complex and variable. In this paper, we study the real-time measurement technique of a near-surface atmospheric turbulence profile of an airship-borne laser communication system based on the principle of light intensity scintillation. Aiming at the influence of an avalanche photon diode detector system noise and environmental factors such as background light and platform vibration on the measurement results, a noise-canceling scintillation index calculation method, combined with a wavelet threshold denoising method, is proposed to improve the accuracy of atmospheric turbulence profile measurements. We build a communication distance of 12 km airship-borne laser communication experiment and carry out a real-time measurement of turbulence profile under 1 km near the ground without affecting the laser communication rate of 2.5 Gbps data transmission. The experimental results show that the atmospheric turbulence profile measured in real time follows the same trend as the theoretical simulation curve of the Hufnagel-Valley model, and the jitter of the measured values after denoising is significantly smaller than that of the measured values without denoising. The research results provide technical guidance and data support to promote the development of space laser communication and adaptive optics.

19.
Postgrad Med J ; 98(1162): 584-590, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33837126

RESUMO

STUDY PURPOSE: Deleterious mutations would be rapidly purged from natural populations along with the extinction of their carriers. The currently observed mutations in existing species are mostly neutral. The inaccessibility of deleterious mutations impedes the functional studies on how these mutations affect the fitness at individual level. STUDY DESIGN: The connection between the deleterious genotype and the non-adaptive phenotype could be bridged by sequencing the genome before extinction. Although this approach is no longer feasible for evolutionary biologists, it is feasible for cancer biologists by profiling the mutations in tumour samples which are so deleterious that the carriers hardly live. RESULTS: By comparing the derived mutation profile between normal populations and patients with liver cancer, we found that the shared mutations, which are highly deleterious, are suppressed to low allele frequencies in normal populations and tissues, but show remarkably high frequency in tumours. The density of shared mutations is negatively correlated with gene conservation and expression levels. CONCLUSIONS: Deleterious mutations are suppressed in functionally important genes as well as in normal populations. This work deepened our understanding on how natural selection act on deleterious mutations by analogising the cancer evolution to species evolution, which are essentially the same molecular process but at different time scales.


Assuntos
Evolução Molecular , Neoplasias Hepáticas , Seleção Genética , Perfilação da Expressão Gênica , Frequência do Gene , Genótipo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Mutação
20.
Mikrochim Acta ; 189(7): 251, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35680710

RESUMO

A sensitive nanopipette sensor is established through a unique design of host-guest recognition, which could be further enhanced by the introduction of gold nanoparticles (Au NPs). Generally, the nanopipette is conjugated with caboxylatopillar[5]arenes (CP[5]) or carboxylated leaning pillar[6]arene (CLP[6]) to generate recognition sites. After the addition of pesticide molecules, they would be captured by CP[5] (or CLP[6]), resulting in a significant electronegativity change on the nanopipette's inner surface, which could be determined by the ionic current change. The CP[5]-modified nanopipette exhibited reliable selectivity for paraquat, while the CLP[6]-modified nanopipette showed an ability of detection for both paraquat and diquat. The addition of Au NPs improved the selectivity and sensitivity of the CP[5]-Au NP-modified nanopipette for paraquat sensing. After optimization by lowering the size of the Au NPs, CP[5]-Au NPs (3 nm)-modified nanopipettes achieved lower detection limits of 0.034 nM for paraquat. Furthermore, in real sample analysis, this sensor demonstrates exceptional sensitivity and selectivity. This study provides a new strategy to develop nanopipette sensors for practical small molecule detection. The gold nanoparticles enhanced quartz nanopipette sensor based on host-guest interaction was firstly established, which could achieve an excellent limit of detection of 3.4 × 10-11 mol/L for paraquat.


Assuntos
Ouro , Nanopartículas Metálicas , Técnicas Eletroquímicas , Ouro/química , Nanopartículas Metálicas/química , Paraquat/análise
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