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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38546325

RESUMO

Expression quantitative trait loci (eQTLs) are used to inform the mechanisms of transcriptional regulation in eukaryotic cells. However, the specificity of genome-wide eQTL identification is limited by stringent control for false discoveries. Here, we described a method based on the non-homogeneous Poisson process to identify 125 489 regions with highly frequent, multiple eQTL associations, or 'eQTL-hotspots', from the public database of 59 human tissues or cell types. We stratified the eQTL-hotspots into two classes with their distinct sequence and epigenomic characteristics. Based on these classifications, we developed a machine-learning model, E-SpotFinder, for augmented discovery of tissue- or cell-type-specific eQTL-hotspots. We applied this model to 36 tissues or cell types. Using augmented eQTL-hotspots, we recovered 655 402 eSNPs and reconstructed a comprehensive regulatory network of 2 725 380 cis-interactions among eQTL-hotspots. We further identified 52 012 modules representing transcriptional programs with unique functional backgrounds. In summary, our study provided a framework of epigenome-augmented eQTL analysis and thereby constructed comprehensive genome-wide networks of cis-regulations across diverse human tissues or cell types.


Assuntos
Epigenoma , Epigenômica , Humanos , Bases de Dados Factuais , Células Eucarióticas , Aprendizado de Máquina
2.
BMC Genomics ; 25(1): 483, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38750461

RESUMO

BACKGROUND: Multiple enhancers co-regulating the same gene is prevalent and plays a crucial role during development and disease. However, how multiple enhancers coordinate the same gene expression across various cell types remains largely unexplored at genome scale. RESULTS: We develop a computational approach that enables the quantitative assessment of enhancer specificity and selectivity across diverse cell types, leveraging enhancer-promoter (E-P) interactions data. We observe two well-known gene regulation patterns controlled by enhancer clusters, which regulate the same gene either in a limited number of cell types (Specific pattern, Spe) or in the majority of cell types (Conserved pattern, Con), both of which are enriched for super-enhancers (SEs). We identify a previously overlooked pattern (Variable pattern, Var) that multiple enhancers link to the same gene, but rarely coexist in the same cell type. These three patterns control the genes associating with distinct biological function and exhibit unique epigenetic features. Specifically, we discover a subset of Var patterns contains Shared enhancers with stable enhancer-promoter interactions in the majority of cell types, which might contribute to maintaining gene expression by recruiting abundant CTCF. CONCLUSIONS: Together, our findings reveal three distinct E-P regulation patterns across different cell types, providing insights into deciphering the complexity of gene transcriptional regulation.


Assuntos
Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Humanos , Biologia Computacional/métodos
3.
Clin Lab ; 70(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38868868

RESUMO

BACKGROUND: Klinefelter syndrome is a common sex chromosome abnormality in males, characterized by an extra X chromosome compared to normal males. Glucose-6-phosphate dehydrogenase deficiency (G6PD) is an X-linked incomplete dominant defect disorder. In this study, we reported the unexpected detection of Klinefelter syndrome in a patient with G6PD. METHODS: G6PD enzyme activity was measured by immunoenzyme assay, and genetic analysis was performed using a fluorescent PCR melting curve method (PCR-melting curve). Sex chromosome number abnormalities were detected by multiplex ligation-dependent probe amplification (MLPA). The patient also underwent peripheral blood chromosome karyotype analysis. RESULTS: The patient's G6PD and 6PGD enzyme activities were 21.34 U/L and 22.85 U/L, respectively, and their ratio was below the reference range (0.93). The PCR-melting curve displayed a c.1388 heterozygous mutation in this boy, and the Sanger sequencing provided the same results. MLPA results suggested the presence of approxi-mately two copies of the X-chromosome in the boy. Finally, chromosome karyotype analysis confirmed that the boy had Klinefelter syndrome with a karyotype of 47, XXY. CONCLUSIONS: Klinefelter syndrome was accidentally detected during G6PD genetic analysis in a male. X-chromosomes can interfere with the results of G6PD genetic analysis and should be noted.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Glucosefosfato Desidrogenase , Síndrome de Klinefelter , Humanos , Síndrome de Klinefelter/genética , Síndrome de Klinefelter/diagnóstico , Síndrome de Klinefelter/complicações , Masculino , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Glucosefosfato Desidrogenase/genética , Cariotipagem , Mutação , Testes Genéticos/métodos , Cromossomos Humanos X/genética
4.
Clin Lab ; 70(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38965958

RESUMO

BACKGROUND: New hemoglobin (Hb) variants are constantly being updated as assays are developed and the testing population expands. Here, we report a novel Hb variant, named Hb Guigang. METHODS: Hemoglobin (Hb) analysis was analyzed by capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC). Glycated hemoglobin was performed by CE and HPLC. Routine genetic analysis was done with Gap-PCR and PCR-reverse dot-blot hybridization. The hemoglobin variant was identified by Sanger sequencing. RESULTS: CE of three cases showed the presence of Hb variants in Zone 5 and Zone 12, respectively. HPLC indicated an elevated P3 peak, suggesting the possible presence of the Hb variant. Hb A1c was measured by CE and HPLC, and the results were 6.7% and 4.76%, respectively. Sanger sequencing confirmed an AAG˃AAT mutation at codon 90 of the HBA1 gene. This mutation was reported for the first time, and we named it Hb Guigang based on the proband's place of residence. CONCLUSIONS: Hb Guigang with normal hematological parameters was separated and quantified by CE, whereas HPLC suggested that Hb Guigang co-eluted with the P3 peaks and could not be quantified.


Assuntos
Eletroforese Capilar , Hemoglobinas Glicadas , Hemoglobinas Anormais , alfa-Globinas , Humanos , Hemoglobinas Anormais/genética , alfa-Globinas/genética , Cromatografia Líquida de Alta Pressão , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Masculino , Feminino , Mutação , Análise Mutacional de DNA , Adulto
5.
Artigo em Inglês | MEDLINE | ID: mdl-38836725

RESUMO

Background: Peritoneal lesions present diagnostic challenges, necessitating precise imaging techniques. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) offers a promising approach for accurate diagnosis, aiding in optimal patient management and treatment planning. Objective: This study aims to assess the diagnostic efficacy of EUS-FNA in peritoneal lesions to offer insight in guiding optimal patient management. Methods: A prospective observational study was conducted, and a total of 58 patients who underwent EUS-FNA of the peritoneum at our hospital between October 2021 and November 2021 were included. The ultrasound diagnostic instrument facilitated puncture guidance, with 2-5 punctures performed in various parts of the selected peritoneal lesion areas. The analysis encompassed evaluating the sensitivity, specificity, positive predictive value, and negative predictive value of biopsy for diagnosing peritoneal-associated lesions, alongside assessing the number of punctures, puncture satisfaction, and incidence of postoperative complications. Results: The included patients undergoing EUS-FNA revealed that 41 (70.69%) had malignant lesions, while 17 (29.31%) presented with benign lesions. The diagnostic accuracy of EUS-FNA for peritoneal lesions was determined to be 94.83%, with a diagnostic sensitivity of 97.30% for malignant tumors, specificity of 90.48%, positive predictive value of 94.74%, and negative predictive value of 95%. Lesions exhibited a size range of 2.5cm × 2.9cm to 15.2cm × 9.8cm. Each patient underwent 2-5 punctures (3.3 ± 1.4), with a puncture satisfaction rate of 96.55%. The incidence of postoperative complications following EUS-FNA was found to be 3.45%. Conclusion: EUS-FNA exhibits substantial diagnostic utility for peritoneal-related lesions, marked by exceptional accuracy, sensitivity, specificity, and favorable safety. Its clinical adoption is warranted, promising improved patient care and management.

6.
Chaos ; 34(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856734

RESUMO

In this paper, a new stochastic epidemic model is established and the dynamical behavior of its solutions is studied for this model. A deterministic epidemic model (ordinary differential equation) is first proposed by considering the isolation mechanism, and the transmission probability function is determined by a Wells-Riley model method to analyze the transmission in the quarantine. For this deterministic model, the basic reproduction number R0 is computed and it is used to determine the existence of disease-free and positive equilibria. The linearized stability of the equilibria is also discussed by analyzing the distribution of eigenvalues of the linear system. Following that, a corresponding stochastic epidemic model is further established by introducing stochastic disturbance. Then, the extinction result of the model is derived also with the help of the basic reproduction number R0s. Furthermore, by applying the theory of Markov semigroups, it is proved that the densities of the distributions of the solutions can converge to an invariant density or sweeping under certain conditions. At last, some numerical simulations are provided and discussed to illustrate the practicability of the model and the obtained theoretical results.

8.
Dalton Trans ; 53(13): 5749-5769, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38441123

RESUMO

With the rapidly growing demand for clean energy and energy interconnection, there is an urgent need for rapid and high-capacity energy storage technologies to realize large-scale energy storage, transfer energy, and establish the energy internet. Supercapacitors, which have advantages such as high specific capacitance, fast charging and discharging rates, and long cycle lifetimes, are being widely used in electric vehicles, information technology, aerospace, and other fields. The performance of supercapacitors is crucially dependent on electrode materials. These can be categorized into electric double-layer capacitors and pseudocapacitors, primarily made from carbon and transition metal oxides, respectively. However, effectively monitoring the physicochemical properties of electrode materials during preparation and processing is challenging, which limits the improvement of supercapacitors' performance. Plasma materials preparation technology can effectively affect the materials preparation processing by energetic electrons, ions, free radicals, and multiple effects in plasma, which are easily manipulated by operation parameters. Therefore, plasma material preparation technology is considered a promising method to precisely monitor the physicochemical and electrochemical properties of energy storage materials and has been widely studied. This paper provides an overview of plasma materials preparation mechanisms, and details of the plasma technology application in the preparation of transition metal hybrids, carbon, and composite electrode materials, as well as a comparison with traditional methods. In conclusion, the advantages, challenges, and research directions of plasma materials preparation technology in the field of electrode materials preparation are summarized.

9.
Sci Rep ; 14(1): 393, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172276

RESUMO

Boron is an essential trace element with roles in growth, development, and physiological functions; however, its mechanism of action is still unclear. In this study, the regulatory roles of the PI3K/Akt signaling pathway on boron-induced changes in barrier function, proliferation, and apoptosis in rat intestinal epithelial cells were evaluated. Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein expression levels of PCNA were higher, while the proportions of cells in the G0/G1 and S phases, apoptosis rate, and caspase-3 mRNA and protein expression levels were lower in cells treated with 0.8 mmol/L boron than in control IEC-6 cells (P < 0.01 or P < 0.05). However, 40 mmol/L boron decreased ZO-1 and Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein levels of PCNA and increased the apoptosis rate and caspase-3 mRNA expression (P < 0.01 or P < 0.05). After specifically blocking PI3K and Akt signals (using LY294002 and MK-2206 2HCL), 0.8 mmol/L boron had no effects on Occludin, PCNA level, apoptosis rates, and caspase-3 levels (P < 0.05); however, the proliferation rate and PCNA levels decreased significantly (P < 0.01 or P < 0.05). The addition of 40 mmol/L boron did not affect ZO-1 and Occludin levels and did not affect the apoptosis rate or PCNA and caspase-3 levels. These results suggested that the PI3K/Akt signaling pathway mediates the effects of low-dose boron on IEC-6 cells.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Caspase 3/metabolismo , Boro/farmacologia , Boro/metabolismo , Ocludina/genética , Ocludina/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proliferação de Células , Transdução de Sinais , Células Epiteliais/metabolismo , Apoptose , RNA Mensageiro/metabolismo
10.
Comput Biol Med ; 171: 108113, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368754

RESUMO

BACKGROUND: The emergence of single-cell technology offers a unique opportunity to explore cellular similarity and heterogeneity between precancerous diseases and solid tumors. However, there is lacking a systematic study for identifying and characterizing similarities at single-cell resolution. METHODS: We developed SIMarker, a computational framework to detect cellular similarities between precancerous diseases and solid tumors based on gene expression at single-cell resolution. Taking hepatocellular carcinoma (HCC) as a case study, we quantified the cellular and molecular connections between HCC and cirrhosis. Core analysis modules of SIMarker is publicly available at https://github.com/xmuhuanglab/SIMarker ("SIM" means "similarity" and "Marker" means "biomarkers). RESULTS: We found PGA5+ hepatocytes in HCC showed cirrhosis-like characteristics, including similar transcriptional programs and gene regulatory networks. Consequently, the genes constituting the gene expression program of these cirrhosis-like subpopulations were designated as cirrhosis-like signatures (CLS). Strikingly, our utilization of CLS enabled the development of diagnosis and prognosis biomarkers based on within-sample relative expression orderings of gene pairs. These biomarkers achieved high precision and concordance compared with previous studies. CONCLUSIONS: Our work provides a systematic method to investigate the clinical translational significance of cellular similarities between HCC and cirrhosis, which opens avenues for identifying similar paradigms in other categories of cancers and diseases.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Lesões Pré-Cancerosas , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Transcriptoma , Cirrose Hepática/diagnóstico , Cirrose Hepática/genética , Biomarcadores , Biomarcadores Tumorais/genética
11.
Comput Biol Med ; 174: 108391, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38613887

RESUMO

BACKGROUND: Liquid chromatography-mass spectrometry (LC-MS)-based quantitative phosphoproteomics has been widely used to detect thousands of protein phosphorylation modifications simultaneously from the biological specimens. However, the complicated procedures for analyzing phosphoproteomics data has become a bottleneck to widening its application. METHODS: Here, we develop PhosMap, a versatile and scalable tool to accomplish phosphoproteomics data analysis. A standardized phosphorylation data format was created for data analyses, from data preprocessing to downstream bioinformatic analyses such as dimension reduction, differential phosphorylation analysis, kinase activity, survival analysis, and so on. For better usability, we distribute PhosMap as a Docker image for easy local deployment upon any of Windows, Linux, and Mac system. RESULTS: The source code is deposited at https://github.com/BADD-XMU/PhosMap. A free PhosMap webserver (https://huggingface.co/spaces/Bio-Add/PhosMap), with easy-to-follow fashion of dashboards, is curated for interactive data analysis. CONCLUSIONS: PhosMap fills the technical gap of large-scale phosphorylation research by empowering researchers to process their own phosphoproteomics data expediently and efficiently, and facilitates better data interpretation.


Assuntos
Biologia Computacional , Fosfoproteínas , Proteômica , Software , Proteômica/métodos , Fosfoproteínas/análise , Fosfoproteínas/metabolismo , Biologia Computacional/métodos , Humanos , Fosforilação , Espectrometria de Massas/métodos , Cromatografia Líquida/métodos
12.
Adv Sci (Weinh) ; 11(15): e2305938, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342621

RESUMO

Kesterite is an earth-abundant energy material with high predicted power conversion efficiency, making it a sustainable and promising option for photovoltaics. However, a large open circuit voltage Voc deficit due to non-radiative recombination at intrinsic defects remains a major hurdle, limiting device performance. Incorporating Ge into the kesterite structure emerges as an effective approach for enhancing performance by manipulating defects and morphology. Herein, how different amounts of Ge affect the kesterite growth pathways through the combination of advanced microscopy characterization techniques are systematically investigated. The results demonstrate the significance of incorporating Ge during the selenization process of the CZTSSe thin film. At high temperature, the Ge incorporation effectively delays the selenization process due to the formation of a ZnSe layer on top of the metal alloys through decomposition of the Cu-Zn alloy and formation of Cu-Sn alloy, subsequently forming of Cu-Sn-Se phase. Such an effect is compounded by more Ge incorporation that further postpones kesterite formation. Furthermore, introducing Ge mitigates detrimental "horizontal" grain boundaries by increasing the grain size on upper layer. The Ge incorporation strategy discussed in this study holds great promise for improving device performance and grain quality in CZTSSe and other polycrystalline chalcogenide solar cells.

13.
J Neurointerv Surg ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914461

RESUMO

BACKGROUND: Carotid web (CaW) is a risk factor for ischemic stroke, mainly in young patients with stroke of undetermined etiology. Its detection is challenging, especially among non-experienced physicians. METHODS: We included patients with CaW from six international trials and registries of patients with acute ischemic stroke. Identification and manual segmentations of CaW were performed by three trained radiologists. We designed a two-stage segmentation strategy based on a convolutional neural network (CNN). At the first stage, the two carotid arteries were segmented using a U-shaped CNN. At the second stage, the segmentation of the CaW was first confined to the vicinity of the carotid arteries. Then, the carotid bifurcation region was localized by the proposed carotid bifurcation localization algorithm followed by another U-shaped CNN. A volume threshold based on the derived CaW manual segmentation statistics was then used to determine whether or not CaW was present. RESULTS: We included 58 patients (median (IQR) age 59 (50-75) years, 60% women). The Dice similarity coefficient and 95th percentile Hausdorff distance between manually segmented CaW and the algorithm segmented CaW were 63.20±19.03% and 1.19±0.9 mm, respectively. Using a volume threshold of 5 mm3, binary classification detection metrics for CaW on a single artery were as follows: accuracy: 92.2% (95% CI 87.93% to 96.55%), precision: 94.83% (95% CI 88.68% to 100.00%), sensitivity: 90.16% (95% CI 82.16% to 96.97%), specificity: 94.55% (95% CI 88.0% to 100.0%), F1 measure: 0.9244 (95% CI 0.8679 to 0.9692), area under the curve: 0.9235 (95%CI 0.8726 to 0.9688). CONCLUSIONS: The proposed two-stage method enables reliable segmentation and detection of CaW from head and neck CT angiography.

14.
Cancer Cell ; 42(8): 1415-1433.e12, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39029466

RESUMO

The tumor microenvironment (TME) has a significant impact on tumor growth and immunotherapy efficacies. However, the precise cellular interactions and spatial organizations within the TME that drive these effects remain elusive. Using advanced multiplex imaging techniques, we have discovered that regulatory T cells (Tregs) accumulate around lymphatic vessels in the peripheral tumor stroma. This localized accumulation is facilitated by mature dendritic cells enriched in immunoregulatory molecules (mregDCs), which promote chemotaxis of Tregs, establishing a peri-lymphatic Treg-mregDC niche. Within this niche, mregDCs facilitate Treg activation, which in turn restrains the trafficking of tumor antigens to the draining mesenteric lymph nodes, thereby impeding the initiation of anti-tumor adaptive immune responses. Disrupting Treg recruitment to mregDCs inhibits tumor progression. Our study provides valuable insights into the organization of TME and how local crosstalk between lymphoid and myeloid cells suppresses anti-tumor immune responses.


Assuntos
Células Dendríticas , Linfócitos T Reguladores , Microambiente Tumoral , Linfócitos T Reguladores/imunologia , Animais , Microambiente Tumoral/imunologia , Camundongos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Vasos Linfáticos/imunologia , Vasos Linfáticos/metabolismo , Camundongos Endogâmicos C57BL , Linfonodos/imunologia , Linhagem Celular Tumoral , Neoplasias/imunologia , Neoplasias/metabolismo
15.
Front Psychol ; 14: 1286463, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268805

RESUMO

It has become an emerging idea for fitness apps to be gamified to intrinsically and extrinsically motivate user's usage intention or behavior. For the long-term success of gamified fitness apps, understanding what and how various motivations affect continued use is critical. A combination of qualitative and quantitative methodologies was used to explore two research questions concerning gamified fitness applications. Specifically, the research questions focused on understanding the impacts of intrinsic and extrinsic motivations on continued usage. Additionally, the study aimed to investigate whether extrinsic motivations enhance or diminish the influence of intrinsic motivations. Results from qualitative study identified three intrinsic motivations (self-development, self-control and hedonic motivation) and two extrinsic motivations (social recognition and financial reward) in gamified fitness apps. Results from quantitative study indicated that intrinsic motivations (formed by self-development, self-control and hedonic motivation), financial reward and social recognition could significantly improve intention for continued use; and further, both financial reward and social recognition could crowd-in intrinsic motivations. This research offers insights into the phenomenon of motivation crowding effects on the intention to continue using gamified fitness apps.

17.
Nat Comput Sci ; 3(7): 582-583, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38177743
18.
Artigo em Inglês | IMSEAR | ID: sea-33175

RESUMO

The genotype of Orientia tsutsugamushi DNA from mites in the Xisa archipelago of China were identified. A natural focus of tsutsugamushi disease in the archipelago was found. The DNA sequence that codes for the 56 kDa protein of O. tsutsugamushi was amplified by nested polymerase chain reaction (N-PCR). The purified positive products were cloned into a pGEM-T vector and sequenced. The DNA sequence was compared with various sequences on the internet for sequence homology. A 507 bp DNA fragment encoding the 56 kDa protein was amplified from the samples. The sequence homology was 85% (Karp strain), 68% (Gilliam strain), 65% (Kato strain), and 67% (Yonchon strain). Orientia tsutsugamushi is carried by the mites of the Xisa archipelago; the main genotype is the Karp strain.


Assuntos
Animais , Técnicas de Tipagem Bacteriana/métodos , China , DNA Bacteriano/análise , Genótipo , Humanos , Ácaros/microbiologia , Orientia tsutsugamushi/classificação , Polimorfismo de Fragmento de Restrição , Valores de Referência
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