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Single-cell RNA sequencing (scRNA-seq) has emerged as a powerful tool in genomics research, enabling the analysis of gene expression at the individual cell level. However, scRNA-seq data often suffer from a high rate of dropouts, where certain genes fail to be detected in specific cells due to technical limitations. This missing data can introduce biases and hinder downstream analysis. To overcome this challenge, the development of effective imputation methods has become crucial in the field of scRNA-seq data analysis. Here, we propose an imputation method based on robust and non-negative matrix factorization (scRNMF). Instead of other matrix factorization algorithms, scRNMF integrates two loss functions: L2 loss and C-loss. The L2 loss function is highly sensitive to outliers, which can introduce substantial errors. We utilize the C-loss function when dealing with zero values in the raw data. The primary advantage of the C-loss function is that it imposes a smaller punishment for larger errors, which results in more robust factorization when handling outliers. Various datasets of different sizes and zero rates are used to evaluate the performance of scRNMF against other state-of-the-art methods. Our method demonstrates its power and stability as a tool for imputation of scRNA-seq data.
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Cell identity annotation for single-cell transcriptome data is a crucial process for constructing cell atlases, unraveling pathogenesis, and inspiring therapeutic approaches. Currently, the efficacy of existing methodologies is contingent upon specific data sets. Nevertheless, such data are often sourced from various batches, sequencing technologies, tissues, and even species. Notably, the gene regulatory relationship remains unaffected by the aforementioned factors, highlighting the extensive gene interactions within organisms. Therefore, we propose scHGR, an automated annotation tool designed to leverage gene regulatory relationships in constructing gene-mediated cell communication graphs for single-cell transcriptome data. This strategy helps reduce noise from diverse data sources while establishing distant cellular connections, yielding valuable biological insights. Experiments involving 22 scenarios demonstrate that scHGR precisely and consistently annotates cell identities, benchmarked against state-of-the-art methods. Crucially, scHGR uncovers novel subtypes within peripheral blood mononuclear cells, specifically from CD4+ T cells and cytotoxic T cells. Furthermore, by characterizing a cell atlas comprising 56 cell types for COVID-19 patients, scHGR identifies vital factors like IL1 and calcium ions, offering insights for targeted therapeutic interventions.
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Revealing and clarifying the chemical reaction processes and mechanisms inside the batteries will bring a great help to the controllable preparation and performance modulation of batteries. Advanced characterization techniques based on synchrotron radiation (SR) have accelerated the development of various batteries over the past decade. In situ SR techniques have been widely used in the study of electrochemical reactions and mechanisms due to their excellent characteristics. Herein, the three most wide and important synchrotron radiation techniques used in battery research were systematically reviewed, namely X-ray absorption fine structure (XAFS) spectroscopy, small-angle X-ray scattering (SAXS), and X-ray diffraction (XRD). Special attention is paid to how these characterization techniques are used to understand the reaction mechanism of batteries and improve the practical characteristics of batteries. Moreover, the in situ combining techniques advance the acquisition of single scale structure information to the simultaneous characterization of multiscale structures, which will bring a new perspective to the research of batteries. Finally, the challenges and future opportunities of SR techniques for battery research are featured based on their current development.
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Untreated or inadequately treated silver-containing wastewater may pose adverse effects on hu-man health and the ecological environment. Currently, significant progress has been made in the treatment of Ag(I) in wastewater using adsorption methods, with adsorbents playing a pivotal role in this process. This paper provides a systematic review of various adsorbents for the recovery and treatment of Ag(I) in wastewater, including MOFs, COFs, transition metal sulfides, metal oxides, biomass materials, and other polymeric materials. The adsorption mechanisms of these materials for Ag(I) are elaborated upon, along with the challenges currently faced. Furthermore, insights into optimizing adsorbents and developing novel adsorbents are proposed in this study.
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Efficient interactions between an adhesive and a substrate surface at the molecular level are the basis for the formation of robust adhesion, which substantially relies on interfacial wetting. However, strong adhesives usually improve cohesion but compromise interfacial properties. Herein, we have reported a kind of robust supramolecular adhesive based on the outstanding mobility and interfacial wettability of adhesive precursors. In situ fast photopolymerization endows supramolecular adhesives with more outstanding adhesion for both smooth and rough surfaces in air and underwater in contrast to their counterparts from thermal polymerization. In addition to their low viscosity and high monomer concentration, supramolecular adhesive precursors without any organic solvents possess well-defined hydrogen bonding interactions. These superior properties consistently contribute to the wetting of the substrate and the formation of adhesive polymers with high molecular weights. This work highlights that enhancing interfacial wetting between an adhesive and a substrate is a promising route to achieving robust adhesion.
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Recurrent respiratory papillomatosis (RRP) is a rare benign tumor caused mainly by the infection of the respiratory tract epithelial cells by the human papillomavirus (HPV) type 6/11. However, the specific mechanisms underlying the inhibition of the host's innate immune response by HPV remain unclear. For this purpose, we employed single-cell RNA sequencing to analyze the states of various immune cells in RRP samples post-HPV infection and utilized a cellular model of HPV infection to elucidate the mechanisms by which HPV evades the innate immune system in RRP. The results revealed distinct immune cell heterogeneity in RRP and demonstrated that HPV11 E7 can inhibit the phosphorylation of the stimulator of interferon genes protein, thereby circumventing the body's antiviral response. In vitro co-culture experiments demonstrated that stimulation of macrophages to produce interferon-beta induced the death of HPV-infected epithelial cells, also reducing HPV viral levels. In summary, our study preliminarily identifies the potential mechanisms by which HPV evades the host's antiviral immune response, as well as the latent antiviral functions exhibited by activated macrophages. This research serves as an initial exploration of antiviral immune evasion in RRP, laying a solid foundation for investigating immunotherapeutic approaches for the disease.IMPORTANCESurgical tumor reduction is the most common treatment for recurrent respiratory papillomatosis (RRP). One of the characteristics of RRP is its persistent recurrence, and multiple surgeries are usually required to control the symptoms. Recently, some adjuvant therapies have shown effectiveness, but none of them can completely clear human papillomavirus (HPV) infection, and thus, a localized antiviral immune response is significant for disease control; after all, HPV infection is limited to the epithelium. Inhibition of interferon-beta (IFN-ß) secretion by HPV11 E7 viral proteins in epithelial cells by affecting stimulator of interferon genes phosphorylation may account for the persistence of low-risk HPV replication in the RRP. Moreover, suppression of the IFN-I pathway in RRP cell types might provide clues regarding the hyporeactive function of local immune cells. However, activation of macrophage groups to produce IFN-ß can still destroy HPV-infected cells.
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Papillomavirus Humano 11 , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus , Infecções Respiratórias , Adulto , Feminino , Humanos , Masculino , Células Epiteliais/virologia , Células Epiteliais/imunologia , Papillomavirus Humano 11/genética , Papillomavirus Humano 11/imunologia , Evasão da Resposta Imune , Imunidade Inata , Interferon beta/metabolismo , Interferon beta/imunologia , Interferon beta/genética , Macrófagos/imunologia , Macrófagos/virologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas E7 de Papillomavirus/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/imunologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Infecções Respiratórias/virologia , Infecções Respiratórias/imunologiaRESUMO
In this study, the effects of microwave treatment on protease activity, dough properties and protein quality in sprouted wheat were investigated. Microwave treatment led to a significant (p < 0.05) reduction in protease activity in sprouted wheat. Proteases with a pH optimum of 4.4 (cysteine proteinases) were more susceptible to microwave heating, which contributed mostly to protease inactivation. Significant improvements (p < 0.05) in the dough properties and gluten quality of sprouted wheat were observed, which are probably attributable to the synergistic effectiveness of protease inactivation and heat-induced gluten cross-linking. After microwave treatment, the decrease in the solubility and extractability of protein in sprouted wheat indicated protein polymerization, which was induced by intermolecular disulfide bond cross-linking. The changes in gliadin were less pronounced due to the relatively low temperature of the microwave treatment. The cross-linking in sprouted wheat that occurred after microwave treatment seemed to mainly involve glutenin, especially B/C low-molecular-weight glutenin subunits (B/C-LMW-GSs) in the range of 30-50 kD.
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As a candidate anode material for Li-ion batteries, Bi-based materials have attracted extensive attention from researchers due to their high specific capacity, environmental friendliness, and simple synthesis methods. However, Bi-based anode materials are prone to causing large volume changes during charging and discharging processes, and the effect of these changes on lithium storage performance is still unclear. This work introduces that Bi/C nanocomposites are prepared by the Bi-based MOF precursor calcination method, and that the Bi/C nanocomposite maintains a high specific capacity (931.6 mAh g-1) with good multiplicative performance after 100 cycles at a current density of 100 mA g-1. The structural evolution of Bi/C anode material during the first cycle of charging and discharging is investigated using in situ synchrotron radiation SAXS. The SAXS results indicate that the multistage scatterers of Bi/C composite, used as an anode material during the first lithiation, can be classified into mesopores, interspaces, and Bi nanoparticles. The different nanostructure evolutions of three types of Bi nanoparticles were observed. It is believed that this result will help to further understand the complex reaction mechanism of Bi-based anode materials in Li-ion batteries.
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Transcription factors (TFs) regulation is required for the vast majority of biological processes in living organisms. Some diseases may be caused by improper transcriptional regulation. Identifying the target genes of TFs is thus critical for understanding cellular processes and analyzing disease molecular mechanisms. Computational approaches can be challenging to employ when attempting to predict potential interactions between TFs and target genes. In this paper, we present a novel graph model (PPRTGI) for detecting TF-target gene interactions using DNA sequence features. Feature representations of TFs and target genes are extracted from sequence embeddings and biological associations. Then, by combining the aggregated node feature with graph structure, PPRTGI uses a graph neural network with personalized PageRank to learn interaction patterns. Finally, a bilinear decoder is applied to predict interaction scores between TF and target gene nodes. We designed experiments on six datasets from different species. The experimental results show that PPRTGI is effective in regulatory interaction inference, with our proposed model achieving an area under receiver operating characteristic score of 93.87% and an area under precision-recall curves score of 88.79% on the human dataset. This paper proposes a new method for predicting TF-target gene interactions, which provides new insights into modeling molecular networks and can thus be used to gain a better understanding of complex biological systems.
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Biologia Computacional , Redes Neurais de Computação , Fatores de Transcrição , Biologia Computacional/métodos , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Algoritmos , Redes Reguladoras de Genes/genética , Animais , Bases de Dados Genéticas , Análise de Sequência de DNA/métodosRESUMO
Emerging and recurrent infectious diseases caused by human coronaviruses (HCoVs) continue to pose a significant threat to global public health security. In light of this ongoing threat, the development of a broad-spectrum drug to combat HCoVs is an urgently priority. Herein, we report a series of anti-pan-coronavirus ssDNA aptamers screened using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). These aptamers have nanomolar affinity with the nucleocapsid protein (NP) of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and also show excellent binding efficiency to the N proteins of both SARS, MERS, HCoV-OC43 and -NL63 with affinity KD values of 1.31 to 135.36 nM. Such aptamer-based therapeutics exhibited potent antiviral activity against both the authentic SARS-CoV-2 prototype strain and the Omicron variant (BA.5) with EC50 values at 2.00 nM and 41.08 nM, respectively. The protein docking analysis also evidenced that these aptamers exhibit strong affinities for N proteins of pan-coronavirus and other HCoVs (-229E and -HKU1). In conclusion, we have identified six aptamers with a high pan-coronavirus antiviral activity, which could potentially serve as an effective strategy for preventing infections by unknown coronaviruses and addressing the ongoing global health threat.
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COVID-19 , SARS-CoV-2 , Humanos , Proteínas do Nucleocapsídeo/genética , Antivirais/farmacologiaRESUMO
BACKGROUND: To assess emotion regulation strategies in a clear and direct manner, Emotion Regulation Questionnaire (ERQ) was developed based on the process model of emotion regulation. ERQ primarily assesses an individual's propensity for reappraisal (a cognitive change in the individual's psychological state in specific situations) and expressive suppression (a regulatory response where an individual alters their emotional response after the onset of an emotional reaction). Recent studies have suggested that the abbreviated 8-item version of the ERQ exhibits comparable model fit to the original version. The present study aimed to explore the psychometric properties and assess cross-gender invariance of the ERQ-8 in Chinese university students. METHODS: University students from Jiangsu Province participated in this study. Participants completed self-report surveys assessing emotion regulation strategies. It was conducted from May 2022 to July 2022. The study employed confirmatory factor analysis (CFA) to assess the two-factor model of ERQ-8 and measurement invariance across male and female samples. RESULTS: The mean age of 1534 participants was 19.83 years (SD = 1.54), and the majority were female (70.4%). The initial ERQ-10 model with ten items demonstrated good fit for all indicators, CFI (Comparative Fit index) = 0.967, TLI (Tucker-Lewis Index) = 0.957, RMSEA (Root Mean Square Error of Approximation) = 0.043, SRMR (Standardised Root Mean Square Residual) = 0.029. However, to assess the fit of the previously proposed ERQ-8 model, two items (Q1 and Q3) were excluded. The fit of the ERQ-8 model was further improved (CFI = 0.989, TLI = 0.984, RMSEA = 0.029, SRMR = 0.021). All item loadings exceeded or were equal to 0.573. Internal consistency analysis based on the ERQ-8 model revealed Cronbach's alpha values of 0.840 for reappraisal and 0.745 for suppression, and corresponding composite reliability (CR) values of 0.846 and 0.747, respectively. Test-retest reliability, assessed using the intraclass correlation coefficient (ICC) (95% CI) within a one-week interval, ranged from 0.537 to 0.679. The correlation coefficient between the two factors was 0.084, significantly below 0.85, which suggested a low correlation between the two factors. The results of the invariance analysis across gender demonstrated that the values of ΔCFI and ΔTLI were both below 0.01. It was supported the gender invariance of the ERQ-8 among university students. CONCLUSION: The eight-item ERQ demonstrated validity and reliability in evaluating emotion regulation strategies, and measurement invariance was observed across gender among university students. The ERQ-8 may prove to be a practical and cost-effective tool, particularly in time-constrained situations.
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Regulação Emocional , Humanos , Masculino , Feminino , Psicometria/métodos , Reprodutibilidade dos Testes , Universidades , Inquéritos e Questionários , EstudantesRESUMO
This study investigated a nanostructured lipid carrier (NLC)-gel system containing luteolin (LUT), a potential drug delivery system for the treatment of psoriasis. LUT-NLC was prepared by solvent emulsification ultrasonication method. The particle size was 199.9 ± 2.6 nm, with the encapsulation efficiency of 99.81% and drug loading of 4.06%. X-ray diffractometry (XRD), Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) were used to characterize the LUT-NLC. The NLC was dispersed in Carbomer 940 to form the NLC based gel. The rheological characteristics of LUT-NLC-gel showed an excellent shear-thinning behavior (non-Newtonian properties) and coincided with the Herschel-Bulkley model. LUT-NLC-gel (78.89 µg/cm2) exhibited better permeation properties and released over 36 hours than LUT gel (32.17 µg/cm2). The dye-labeled LUT-NLC presented intense fluorescence in the epidermis and dermis by the visualization of fluorescence and confocal microscopy, and it could accumulate in the hair follicles. The effect of LUT-NLC-gel on imiquimod-induced psoriasis mice was evaluated by psoriasis area severity index scoring, spleen index assay, histopathology, and inflammatory cytokines. These results confirmed that LUT-NLC-gel with high dose (80 mg/kg/day) remarkably reduced the level of inflammatory and proliferation factors such as TNF-α, IL-6, IL-17, and IL-23 in both skin lesions and blood. LUT-NLC-gel improved the macroscopic features. Therefore, the LUT-NLC-gel had great potential as an effective delivery system for skin diseases.
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Nanoestruturas , Psoríase , Camundongos , Animais , Luteolina/uso terapêutico , Portadores de Fármacos/química , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Nanoestruturas/química , Lipídeos/química , Tamanho da PartículaRESUMO
The magnetic CuFe2O4/MnO2 heterojunctions were prepared by hydrothermal method, and the effect of different reaction temperature on the physicochemical properties and catalytic activity was investigated. The CuFe2O4/MnO2 heterojunctions prepared at 100 °C can effectively activate peroxymonosulfate (PMS) at multiple application scenarios for degradation and mineralization of tetracycline, o-nitrophenol and ceftriaxone sodium under indoor light, visible light and dark condition. Additionally, the CuFe2O4/MnO2-PMS system showed high catalytic activity and anti-interference ability for degradation of pharmaceutical pollutants in natural water bodies and industrial wastewater. The TC removal efficiency in Qianhu Lake water, Ganjiang River water and tap water was about 88%, 92% and 89%, respectively. The CuFe2O4/MnO2-PMS system is also effective for actual pharmaceutical wastewater treatment with 77.9% of COD removal efficiency. Interestingly, the reactive species of CuFe2O4/MnO2-PMS system under visible light are different from those in dark condition, and the different catalytic mechanisms at multiple application scenarios were proposed. This work provides new insights into mechanism exploration of heterojunction catalyst for PMS activation.
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Compostos de Manganês , Óxidos , Peróxidos , Água , Preparações FarmacêuticasRESUMO
Obesity has become an ongoing global crisis, since it increases the risks of cardiovascular disease, type 2 diabetes, fatty liver, cognitive decline, and some cancers. Adipose tissue is closely associated with the disorder of lipid metabolism. Several efforts have been made toward the modulation of lipid accumulation, but have been hindered by poor efficiency of cellular uptake, low safety, and uncertain effective dosage. Herein, we design an Fe3O4microsphere-doped composite hydrogel (Fe3O4microspheres @chitosan/ß-glycerophosphate/collagen), termed as Fe3O4@Gel, as the magnetocaloric agent for magnetic hyperthermia therapy (MHT), aiming to promote lipolysis in white adipocytes. The experimental results show that the obtained Fe3O4@Gel displays a series of advantages, such as fast sol-gel transition, high biocompatibility, and excellent magneto-thermal performance. MHT, which is realized by Fe3O4@Gel subjected to an alternating magnetic field, leads to reduced lipid accumulation, lower triglyceride content, and increased mitochondrial activity in white adipocytes. This work shows that Fe3O4@Gel-mediated MHT can effectively promote lipolysis in white adipocytesin vitro, which provides a potential approach to treat obesity and associated metabolic disorders.
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Diabetes Mellitus Tipo 2 , Hipertermia Induzida , Humanos , Lipólise , Adipócitos Brancos , Microesferas , Hidrogéis , Obesidade , Lipídeos , Hipertermia Induzida/métodos , Fenômenos MagnéticosRESUMO
For space-based gravitational wave detection, a laser interferometric measurement system composed of a three-spacecraft formation offers the most rewarding bandwidth of astrophysical sources. There are no oscillators available that are stable enough so that each spacecraft could use its own reference frequency. The conversion between reference frequencies and their distribution between all spacecrafts for the synchronization of the different metrology systems is the job of the inter-spacecraft frequency setting strategy, which is important for continuously acquiring scientific data and suppressing measurement noise. We propose a hierarchical optimization algorithm to solve the frequency setting strategy. The optimization objectives are minimum total readout displacement noise and maximum beat-note frequency feasible range. Multiple feasible parameter combinations were obtained for the Taiji program. These optimized parameters include lower and upper bounds of the beat note, sampling frequency, pilot tone signal frequency, ultrastable clock frequencies, and modulation depth. Among the 20 Pareto optimal solutions, the minimum total readout displacement noise was 4.12 pm/Hz, and the maximum feasible beat-note frequency range was 23 MHz. By adjusting the upper bound of beat-note frequency and laser power transmitted by the telescope, we explored the effects of these parameters on the minimum total readout displacement noise and optimal local laser power in greater depth. Our results may serve as a reference for the optimal design of laser interferometry system instrument parameters and may ultimately improve the detection performance and continuous detection time of the Taiji program.
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In the context of simulating precision laser interferometers, we use several examples to compare two wavefront decomposition methods-the Mode Expansion Method (MEM) and the Gaussian Beam Decomposition (GBD) method-for their precision and applicability. To assess the performance of these methods, we define different types of errors and study their properties. We specify how the two methods can be fairly compared and based on that, compare the quality of the MEM and GBD through several examples. Here, we test cases for which analytic results are available, i.e., non-clipped circular and general astigmatic Gaussian beams, as well as clipped circular Gaussian beams, in the near, far, and extremely far fields of millions of kilometers occurring in space-gravitational wave detectors. Additionally, we compare the methods for aberrated wavefronts and their interaction with optical components by testing reflections from differently curved mirrors. We find that both methods can generally be used for decomposing non-Gaussian beams. However, which method is more accurate depends on the optical system and simulation settings. In the given examples, the MEM more accurately describes non-clipped Gaussian beams, whereas for clipped Gaussian beams and the interaction with surfaces, the GBD is more precise.
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In this paper, we propose a novel time-division multiplexed (TDM) array for a large-scale interferometric fiber-optic hydrophone system, in which we introduce a power-optimized reference probe and effectively reduce the additional white noise while correcting for light source frequency noise. Laser frequency noise usually introduces appreciable phase noise during demodulation of interferometric fiber-optic hydrophones. In the previous means, one would introduce an additional probe isolated from the environment in sensor array, and use it as a reference to calibrate the demodulation results of the other actual sensors. However, while correcting, the reference probe also introduces a large white noise. In our array, the echo of the reference probe is higher than the other sensors, thus solving this problem. The novel array design is applied to our previously proposed fiber-optic hydrophone based on a linear frequency modulated (LFM) light source. Experiments show that the deterioration of phase noise floor caused by additional white noise is improved from at least 3â dB originally to within 1â dB. This paper analyzes the factors that need to be concerned for the successful implementation of correction algorithms in hydrophone systems based on LFM sources. Particular focus is given to the impact of the power optimization of reference probe on the white noise and the corrected phase noise. Our proposal allows a significant relaxation of the demanding linewidth requirement for interferometric hydrophone. It is shown that laser with linewidth of 338.06â MHz can replace that with 1.417 kHz in our new system, while achieves the same demodulation noise floor.
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Although there are several treatments available for gastric cancer (GC), the prognosis of the disease is still poor due to many factors, such as late diagnosis and tumor heterogeneity. To identify potential therapeutic targets, bioinformatics techniques and clinical sample validation were employed and prostate transmembrane protein androgen induced 1 (PMEPA1) was selected for further study. In the present study, we found that elevated PMEPA1 expression correlates with a worse prognosis and weaker anti-tumor immunity in GC patients. Moreover, our study showed that PMEPA1 not only influences cell proliferation, clone formation, invasion, and migration in vitro, but also plays an important role in GC progression in vivo. Mechanically, PMEPA1 exerts its oncogenic effects through activating the Wnt/ß-catenin signaling pathway. Therefore, PMEPA1 is a potential target for treating GC effectively.
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Neoplasias Gástricas , Masculino , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Proteínas de Membrana/genética , Via de Sinalização Wnt , Proliferação de Células/genética , Regulação Neoplásica da Expressão GênicaRESUMO
For space-based gravitational wave (GW) detection, the continuity of detection data acquisition is crucial to the inversion of wave sources and the realization of scientific goals. To control the inter-spacecraft beat-note frequency in an appropriate range for continuous gravitational wave detection and to reduce the upper bound of the beat-note frequency for improving the detection capability, a two-stage optimization algorithm is proposed to solve the offset frequency setting strategy in the Taiji program. The optimization objectives are the maximum offset frequency duration and minimum upper bound of the beat-note frequency. Considering all feasible phase-locked schemes, Doppler frequency shift, and the bandwidth of the phasemeter, a series of offset frequency setting strategies satisfying the conditions was obtained. The solution results show that the upper bound can be reduced to 16 MHz and, in this case, the offset frequency changes nine times with a minimum and maximum offset frequency duration of 90 days and 713 days, respectively. If the Doppler frequency shift is constrained, the minimum upper bound can be reduced to 14 MHz. When the minimum duration is increased, the minimum upper bound is increased. These results show that, by varying the offset frequency a limited number of times, the data continuity requirements of the Taiji program can be satisfied, and the phasemeter development difficulty and detection capability can be balanced, and may provide a reference for the phasemeter design, the setting of phase-locking schemes, and inter-spacecraft offset frequency in the Taiji program.
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Squamous papillomas (SPs) of the head and neck are usually benign lesions associated with human papilloma virus (HPV) infection. However, the reported HPV detection rates vary widely, especially with respect to anatomical distribution. The etiology of SPs in the head and neck remains unclear; analyzing HPV genotypes of SPs based on anatomical sites could assist in clarifying the pathogenesis of SPs in the head and neck. Therefore, the aim of this study was to review the prevalence, subtypes, and anatomical distribution of HPV in head and neck SPs at a hospital in China; we also investigated whether p16, a marker of HPV infection in oropharyngeal carcinoma, could serve as a surrogate marker for HPV in head and neck SPs. The presence of HPV DNA of 23 types (5 low-risk HPV and 18 high-risk HPV types) was detected via real-time PCR. p16 immunohistochemistry was performed using SP sections. Age, sex, anatomical location, and HPV subtype were recorded for each case. In total, 105 SPs were identified, including 47 in the larynx, 42 in the pharynx, 6 in the external auditory canal (EAC), 5 in the oral cavity, and 5 in the nasal cavity. HPV was found in 57 (54.3%) cases, with the highest positivity rate in the larynx (46/47; 97.9%). Only 5/42 (11.9%) patients showed HPV positivity in the pharynx. HPV incidence was highly dependent on the anatomical site. SPs in the larynx and EAC were more likely to carry HPV than those in other anatomical sites. High-risk HPV infections were rarely associated with SPs in the head and neck region. The sensitivity and specificity of p16 immunohistochemistry for HPV infection were 88% and 96%, respectively. There may be an association between p16 and HPV infection in head and neck SPs, but further studies are needed to validate this assertion.