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Creators/Authors contains: "Reyna, Nathan S"

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  1. MicroRNAs are small noncoding nucleotides that serve as intracellular and extracellular signaling molecules. A previous collaboration found miR-127/3p circulation in the blood of breast cancer patients correlated with improved patient recovery and prognosis. While this study exclusively focused on breast cancer patients, data mining of the TCGA databases indicated that miR-127/3p may be positively associated with outcomes in other cancer types. In our study, A549 lung adenocarcinoma cells were transfected with miR-127/3p using Cell Block protocols produced by the Cell Biology Education Consortium (CBEC). After transfection, cell migration (scratch/wound healing) assays were used to determine the role miR-127/3p plays in the tumor microenvironment. To mimic and test this environment, transfected cells were incubated in normal oxygen (normoxic) and low oxygen (hypoxic) environments. We found that miR-127/3p inhibited cell migration in both normal oxygen and hypoxic environments. These results help elucidate the role miR-127/3p plays in the prevention of metastasis and further highlight its potential as a positive biomarker. 
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  2. Infection with hepatitis B virus (HBV) is a main risk factor for hepatocellular carcinoma (HCC). Extracellular vesicles, such as exosomes, play an important role in tumor development and metastasis, including regulation of HBV-related HCC. In this study, we have characterized exosome microRNA and proteins released in vitro from hepatitis B virus (HBV)-related HCC cell lines SNU-423 and SNU-182 and immortalized normal hepatocyte cell lines (THLE2 and THLE3) using microRNA sequencing and mass spectrometry. Bioinformatics, including functional enrichment and network analysis, combined with survival analysis using data related to HCC in The Cancer Genome Atlas (TCGA) database, were applied to examine the prognostic significance of the results. More than 40 microRNAs and 200 proteins were significantly dysregulated (p < 0.05) in the exosomes released from HCC cells in comparison with the normal liver cells. The functional analysis of the differentially expressed exosomal miRNAs (i.e., mir-483, mir-133a, mir-34a, mir-155, mir-183, mir-182), their predicted targets, and exosomal differentially expressed proteins (i.e., POSTN, STAM, EXOC8, SNX9, COL1A2, IDH1, FN1) showed correlation with pathways associated with HBV, virus activity and invasion, exosome formation and adhesion, and exogenous protein binding. The results from this study may help in our understanding of the role of HBV infection in the development of HCC and in the development of new targets for treatment or non-invasive predictive biomarkers of HCC. 
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  3. Fu, Elain (Ed.)
    Biomedicine today is experiencing a shift towards decentralized data collection, which promises enhanced reproducibility and collaboration across diverse laboratory environments. This inter-laboratory study evaluates the performance of biocytometry, a method utilizing engineered bioparticles for enumerating cells based on their surface antigen patterns. In centralized and aggregated inter-lab studies, biocytometry demonstrated significant statistical power in discriminating numbers of target cells at varying concentrations as low as 1 cell per 100,000 background cells. User skill levels varied from expert to beginner capturing a range of proficiencies. Measurement was performed in a decentralized environment without any instrument cross-calibration or advanced user training outside of a basic instruction manual. The results affirm biocytometry to be a viable solution for immunophenotyping applications demanding sensitivity as well as scalability and reproducibility and paves the way for decentralized analysis of rare cells in heterogeneous samples. 
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    Free, publicly-accessible full text available December 9, 2025
  4. ABSTRACT During the COVID-19 pandemic, biology educators were forced to think of ways to communicate with their students, engaging them in science and with the scientific community. For educators using course-based undergraduate research experiences (CUREs), the challenge to have students perform real science, analyze their work, and present their results to a larger scientific audience was difficult as the world moved online. Many instructors were able to adapt CUREs utilizing online data analysis and virtual meeting software for class discussions and synchronous learning. However, interaction with the larger scientific community, an integral component of making science relevant for students and allowing them to network with other young scientists and experts in their fields, was still missing. Even before COVID-19, a subset of students would travel to regional or national meetings to present their work, but most did not have these opportunities. With over 300 million active users, Twitter provided a unique platform for students to present their work to a large and varied audience. The Cell Biology Education Consortium hosted an innovative scientific poster session entirely on Twitter to engage undergraduate researchers with one another and with the much broader community. The format for posting on this popular social media platform challenged students to simplify their science and make their points using only a few words and slides. Nineteen institutions and over one hundred students participated in this event. Even though these practices emerged as a necessity during the COVID-19 pandemic, the Twitter presentation strategy shared in this paper can be used widely. 
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  5. Background: Neoadjuvant chemotherapy (NACT) is an increasingly used approach for treatment of breast cancer. The pathological complete response (pCR) is considered a good predictor of disease-specific survival. This study investigated whether circulating exosomal microRNAs could predict pCR in breast cancer patients treated with NACT. Method: Plasma samples of 20 breast cancer patients treated with NACT were collected prior to and after the first cycle. RNA sequencing was used to determine microRNA profiling. The Cancer Genome Atlas (TCGA) was used to explore the expression patterns and survivability of the candidate miRNAs, and their potential targets based on the expression levels and copy number variation (CNV) data. Results: Three miRNAs before that NACT (miR-30b, miR-328 and miR-423) predicted pCR in all of the analyzed samples. Upregulation of miR-127 correlated with pCR in triple-negative breast cancer (TNBC). After the first NACT dose, pCR was predicted by exo-miR-141, while miR-34a, exo-miR182, and exo-miR-183 predicted non-pCR. A significant correlation between the candidate miRNAs and the overall survival, subtype, and metastasis in breast cancer, suggesting their potential role as predictive biomarkers of pCR. Conclusions: If the miRNAs identified in this study are validated in a large cohort of patients, they might serve as predictive non-invasive liquid biopsy biomarkers for monitoring pCR to NACT in breast cancer. 
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  6. Abstract Biomedicine today is experiencing a shift towards decentralized data collection, which promises enhanced reproducibility and collaboration across diverse laboratory environments. This inter-laboratory study evaluates the performance of biocytometry, a method utilizing engineered bioparticles for enumerating cells based on their surface antigen patterns. In a decentralized framework, spanning 78 assays conducted by 30 users across 12 distinct laboratories, biocytometry consistently demonstrated significant statistical power in discriminating numbers of target cells at varying concentrations as low as 1 cell per 100,000 background cells. User skill levels varied from expert to beginner capturing a range of proficiencies. Measurement was performed in a decentralized environment without any instrument cross-calibration or advanced user training outside of a basic instruction manual. The results affirm biocytometry to be a viable solution for immunophenotyping applications demanding sensitivity as well as scalability and reproducibility and paves the way for decentralized analysis of rare cells in heterogeneous samples. 
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  7. Roux, Simon (Ed.)
    ABSTRACT Chop, DelRio, and GrandSlam are phage with a Siphoviridae morphotype isolated from soil in Arkansas using the host Gordonia terrae 3612. All three are temperate, and their genomes share at least 96% nucleotide identity. These phage are assigned to cluster DI based on gene content similarity to other sequenced actinobacteriophage. 
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  8. null (Ed.)
    ABSTRACT Course-based undergraduate research experiences (CUREs) provide a way for students to gain research experience in a classroom setting. Few examples of cell culture CUREs or online CUREs exist in the literature. The Cell Biology Education Consortium (CBEC) provides a network and resources for instructors working to incorporate cell-culture based research into the classroom. In this article, we provide examples from six instructors from the CBEC network on how they structure their cell-culture CUREs and how they transitioned the labs to online in the spring semester of 2020. We intend for these examples to provide instructors with ideas for strategies to set up cell culture CUREs, how to change that design mid-term, and for creating online CUREs in the future. 
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  9. Ulasov, Ilya (Ed.)