CircPVT1 promotes migration and invasion by regulating miR-490-5p/HAVCR2 axis in osteosarcoma cells

Circular RNAs (circRNAs) play an important role in the progression of osteosarcoma. However, the precise function of circPVT1 in osteosarcoma remains elusive. This study aims to explore the molecular mechanism underlying the involvement of circPVT1 in osteosarcoma cells. We quantified circPVT1 expression using qRT-PCR in both control and osteosarcoma cell lines. To investigate the roles of circPVT1, miR-490-5p and HAVCR2 in vitro, we separately conducted overexpression and inhibition experiments for circPVT1, miR-490-5p and HAVCR2 in HOS and U2OS cells. Cell migration was assessed through wound healing and transwell migration assays, and invasion was measured via the Matrigel invasion assay. To elucidate the regulatory mechanism of circPVT1 in osteosarcoma, a comprehensive approach was employed, including fluorescence in situ hybridization, qRT-PCR, Western blot, bioinformatics, dual-luciferase reporter assay and rescue assay. CircPVT1 expression in osteosarcoma cell lines surpassed that in control cells. The depletion of circPVT1 resulted in a notable reduction in the in vitro migration and invasion of osteosarcoma cells. Mechanism experiments revealed that circPVT1 functioned as a miR-490-5p sequester, and directly targeted HAVCR2. Overexpression of miR-490-5p led to a significant attenuation of migration and invasion of osteosarcoma cells, whereas HAVCR2 overexpression had the opposite effect, promoting these abilities. Additionally, circPVT1 upregulated HAVCR2 expression via sequestering miR-490-5p, thereby orchestrating the migration and invasion in osteosarcoma cells. CircPVT1 orchestrates osteosarcoma migration and invasion by regulating the miR-490-5p/HAVCR2 axis, underscoring its potential as a promising therapeutic target for osteosarcoma

Optimal algorithms for selecting top-k combinations of attributes : theory and applications

Traditional top-k algorithms, e.g., TA and NRA, have been successfully applied in many areas such as information retrieval, data mining and databases. They are designed to discover k objects, e.g., top-k restaurants, with highest overall scores aggregated from different attributes, e.g., price and location. However, new emerging applications like query recommendation require providing the best combinations of attributes, instead of objects. The straightforward extension based on the existing top-k algorithms is prohibitively expensive to answer top-k combinations because they need to enumerate all the possible combinations, which is exponential to the number of attributes. In this article, we formalize a novel type of top-k query, called top-k, m, which aims to find top-k combinations of attributes based on the overall scores of the top-m objects within each combination, where m is the number of objects forming a combination. We propose a family of efficient top-k, m algorithms with different data access methods, i.e., sorted accesses and random accesses and different query certainties, i.e., exact query processing and approximate query processing. Theoretically, we prove that our algorithms are instance optimal and analyze the bound of the depth of accesses. We further develop optimizations for efficient query evaluation to reduce the computational and the memory costs and the number of accesses. We provide a case study on the real applications of top-k, m queries for an online biomedical search engine. Finally, we perform comprehensive experiments to demonstrate the scalability and efficiency of top-k, m algorithms on multiple real-life datasets.Peer reviewe

Identification of circRNA biomarkers in osteosarcoma: An updated systematic review and meta-analysis

Circular RNAs (circRNAs) play a crucial role in cancer development and progression. This study aimed to identify potential circRNA biomarkers for osteosarcoma. Articles published from January 2010 to September 2023 were searched across eight databases to compare circRNA expression profiles in osteosarcoma and control samples (human, animal and cell lines). Meta-analysis was conducted under a random effects model. Subgroup analysis of circRNAs in different samples and tissues was performed. Diagnostic value was evaluated using receiver operator characteristic curves. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis explored functions of circRNA host genes. A circRNA-miRNA-mRNA axis depicted the regulatory mechanism in osteosarcoma. Among 1356 circRNAs with differential expression were identified across 226 original studies, only 74 were reported in at least three published sub-studies. Meta-analysis identified 58 dysregulated circRNAs (52 upregulated and 6 downregulated). Eleven circRNAs consistently showed dysregulation in tissues and cell lines, with hsa_circ_0005721 showing potential as a circulating biomarker in osteosarcoma. Sensitivity analysis demonstrated 97 % consistency. The overall area under the curve was 0.87 (95 % CI, 0.83–0.89). GO and KEGG enrichment analyses revealed host gene involvement in cancer. The circRNA-miRNA-mRNA axis revealed the regulatory axis and interactions within osteosarcoma specifically. This study demonstrates circRNAs as potential diagnostic biomarkers for osteosarcoma. Consistently reported dysregulated circRNAs are potential biomarkers in osteosarcoma pathogenesis, with hsa_circ_0005721 as a potential circulating biomarker for diagnosis and treatment

Synergy of Database Techniques and Machine Learning Models for String Similarity Search and Join

Peer reviewe

Ginsenoside Rh1 Improves the Effect of Dexamethasone on Autoantibodies Production and Lymphoproliferation in MRL/lpr Mice

Ginsenoside Rh1 is able to upregulate glucocorticoid receptor (GR) level, suggesting Rh1 may improve glucocorticoid efficacy in hormone-dependent diseases. Therefore, we investigated whether Rh1 could enhance the effect of dexamethasone (Dex) in the treatment of MRL/lpr mice. MRL/lpr mice were treated with vehicle, Dex, Rh1, or Dex + Rh1 for 4 weeks. Dex significantly reduced the proteinuria and anti-dsDNA and anti-ANA autoantibodies. The levels of proteinuria and anti-dsDNA and anti-ANA autoantibodies were further decreased in Dex + Rh1 group. Dex, Rh1, or Dex + Rh1 did not alter the proportion of CD4+ splenic lymphocytes, whereas the proportion of CD8+ splenic lymphocytes was significantly increased in Dex and Dex + Rh1 groups. Dex + Rh1 significantly decreased the ratio of CD4+/CD8+ splenic lymphocytes compared with control. Con A-induced CD4+ splenic lymphocytes proliferation was increased in Dex-treated mice and was inhibited in Dex + Rh1-treated mice. Th1 cytokine IFN-γ mRNA was suppressed and Th2 cytokine IL-4 mRNA was increased by Dex. The effect of Dex on IFN-γ and IL-4 mRNA was enhanced by Rh1. In conclusion, our data suggest that Rh1 may enhance the effect of Dex in the treatment of MRL/lpr mice through regulating CD4+ T cells activation and Th1/Th2 balance

Boosting the Quality of Approximate String Matching by Synonyms

A string similarity measure quantifies the similarity between two text strings for approximate string matching or comparison. For example, the strings ``\textsf{Sam}'' and ``\textsf{Samuel}'' can be considered to be similar. Most existing work that computes the similarity of two strings only considers syntactic similarities, e.g., number of common words or \qgrams. While this is indeed an indicator of similarity, there are many important cases where syntactically different strings can represent the same real-world object. For example, ``\textsf{Bill}'' is a short form of ``\textsf{William}''; and ``\textsf{Database Management Systems}'' can be abbreviated as ``\textsf{DBMS}''. Given a collection of predefined synonyms, the purpose of this article is to explore such existing knowledge to effectively evaluate the similarity between two strings and efficiently perform similarity searches and joins, thereby boosting the quality of approximate string matching. In particular, we first present an expansion-based framework to measure string similarities efficiently while considering synonyms. We then study efficient algorithms for similarity searches and joins by proposing two novel indexes, called SI-tree and QP-tree, which combine signature filtering and length filtering strategies. In order to improve the efficiency of our algorithms, we develop an estimator to estimate the size of candidates to enable an online selection of signature filters. This estimator provides strong low-error, high-confidence guarantees while requiring only logarithmic space and time costs, thus making our method attractive both in theory and in practice. Finally, the experimental results from a comprehensive study of the algorithms with three real datasets verify the effectiveness and efficiency of our approaches.Peer reviewe

Etiological surveillance of viral diarrhea from 2017 to 2019 in Zhangzhou city, Fujian province, China

BackgroundViral diarrhea is one of the major causes of morbidity and mortality in children. This study aimed to conduct etiological surveillance of viral diarrhea in Zhangzhou city, Fujian province, China, from 2017 to 2019 to identify the prevalence, distribution, and characteristics of viral pathogens causing gastrointestinal infections in the region.MethodsStool samples were collected from patients with acute diarrhea in Zhangzhou city, Fujian province, China, from 2017 to 2019. Rotavirus, norovirus, astrovirus, and adenovirus were detected using fluorescence immunochromatography assay.ResultsOf the total 5,627 samples that were collected, at least one of the viruses (rotavirus, norovirus, astrovirus and adenovirus) was found to be positive in 1,422 samples. Rotavirus, norovirus, astrovirus, and adenovirus, were detected in 53.73, 16.68, 15.52, and 14.97%, respectively. Mixed infections were determined in 17.65% of the positive samples. The predominant mixed infections observed were a combination of norovirus and astrovirus, followed by rotavirus and norovirus, and rotavirus and astrovirus. The highest positive rate was observed in the 12–23-month group for rotavirus and adenovirus, while a significantly higher positive rate was observed for norovirus and astrovirus in the 6–11-month group.ConclusionThese findings from this etiological surveillance highlight the significant burden of viral diarrhea in Zhangzhou city, with rotavirus being the predominant pathogen. The identification of common mixed infections provides insights into the complex nature of viral diarrhea transmission. Target interventions and public health strategies should be implemented, particularly during the winter and spring seasons, to prevent and control the spread of viral pathogens causing gastrointestinal infections in this region