Multiphysics analysis of heat pipe cooled microreactor core with adjusted heat sink temperature for thermal stress reduction using OpenFOAM coupled with neutronics and heat pipe code

Heat-pipe-cooled microreactors (HPRs) have advantages such as a compact design, easy transportation, and improved system reliability and stability. The core of an HPR consists of fuel rods and heat pipes in a monolith, which is a solid block structure containing many holes for the fuel rods and heat pipes. When designing the core of an HPR, high thermal stress and reactivity feedback owing to thermal expansion are important considerations. Therefore, a high-fidelity multiphysics analysis tool is required for accurately analyzing an HPR core. When performing a multiphysics analysis, it is necessary to couple the heat pipe thermal analysis code, thermal-structural analysis code, and neutronics code. To develop a multiphysics analysis tool, OpenFOAM, an open source Computational Fluid Dynamics (CFD) tool, and ANLHTP, a heat pipe thermal analysis code, were coupled. In this process, the structural analysis solver of OpenFOAM was verified, and its limitations were improved. To confirm the proper working of the code, the mini-core problem was analyzed using the OpenFOAM-ANLHTP coupled code. Next, to consider the reactivity feedback, coupling with PRAGMA, a GPU-based continuous-energy-Monte Carlo neutronics code was performed, and the multiphysics analysis capability of the OpenFOAM-ANLHTP-PRAGMA coupled code was confirmed through an analysis of the MegaPower reactor core. To reduce the temperature distribution within the monolith, the temperature distribution of the heat pipe sink was adjusted, and the reduced thermal stress of an HPR core was observed

CRISPR RNAs trigger innate immune responses in human cells

Here, we report that CRISPR guide RNAs (gRNAs) with a 5'-triphosphate group (5'-ppp gRNAs) produced via in vitro transcription trigger RNA-sensing innate immune responses in human and murine cells, leading to cytotoxicity. 5'-ppp gRNAs in the cytosol are recognized by DDX58, which in turn activates type I interferon responses, causing up to similar to 80% cell death. We show that the triphosphate group can be removed by a phosphatase in vitro and that the resulting St-hydroxyl gRNAs in complex with Cas9 or Cpfl avoid innate immune responses and can achieve targeted mutagenesis at a frequency of 95% in primary human CD4(+) T cells. These results are in line with previous findings that chemically synthesized sgRNAs with a 5'-hydroxyl group are much more efficient than in vitro-transcribed (IVT) sgRNAs in human and other mammalian cells. The phosphatase treatment of IVT sgRNAs is a cost-effective method for making highly active sgRNAs, avoiding innate immune responses in human cells.

Antitumorigenic effect of atmospheric-pressure dielectric barrier discharge on human colorectal cancer cells via regulation of Sp1 transcription factor

Human colorectal cancer cell lines (HT29 and HCT116) were exposed to dielectric barrier discharge (DBD) plasma at atmospheric pressure to investigate the anticancer capacity of the plasma. The dose- and time-dependent effects of DBDP on cell viability, regulation of transcription factor Sp1, cell-cycle analysis, and colony formation were investigated by means of MTS assay, DAPI staining, propidium iodide staining, annexin V-FITC staining, Western blot analysis, RT-PCR analysis, fluorescence microscopy, and anchorage-independent cell transformation assay. By increasing the duration of plasma dose times, significant reductions in the levels of both Sp1 protein and Sp1 mRNA were observed in both cell lines. Also, expression of negative regulators related to the cell cycle (such as p53, p21, and p27) was increased and of the positive regulator cyclin D1 was decreased, indicating that the plasma treatment led to apoptosis and cell-cycle arrest. In addition, the sizes and quantities of colony formation were significantly suppressed even though two cancer promoters, such as TPA and epidermal growth factor, accompanied the plasma treatment. Thus, plasma treatment inhibited cell viability and colony formation by suppressing Sp1, which induced apoptosis and cell-cycle arrest in these two human colorectal cancer cell lines.1

Molecular genetic study of novel biomarkers for early diagnosis of oral squamous cell carcinoma

Objectives: Early detection and treatment of an oral squamous cell carcinoma (OSCC) is critical because of its rapid growth, frequent lymph-node metastasis, and poor prognosis. However, no clinically-valuable methods of early diagnosis exist, and genetic analysis of OSCCs has yielded no biomarkers. Study D esign: We investigated the expression of genes associated with inflammation in OSCCs via a quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis of microarray data. Tumor and normal tissues from five patients with an OSCC were used for microarray analysis. Differentially-expressed genes, identified using permutation, local pooled error (LPE), t-tests, and significance analysis of microarrays (SAM), were selected as candidate genetic markers. Results: Two groups corresponding to tissue identity were evident, implying that their differentially-expressed genes represented biological differences between tissues. Fifteen genes were identified using the Student’s paired t-test ( p< 0.05) and the SAM, with a false discovery rate of less than 0.02. Based on gene expression, these 15 genes can be used to classify an OSCC. A genetic analysis of functional networks and ontologies, validated by using a qRT-PCR analysis of the tissue samples, identified four genes, ADAM15, CDC7, IL12RB2 and TNFRSF8, that demonstrated excellent concordance with the microarray data. Conclusions: Our study demonstrated that four genes (ADAM15, CDC7, IL12RB2 and TNFRSF8) had potential as novel biomarkers for the diagnosis and the treatment of an OSCC

Fluoroscopically Guided Balloon Dilation for Benign Anastomotic Stricture in the Upper Gastrointestinal Tract

A benign anastomotic stricture is a common complication of upper gastrointestinal (UGI) surgery and is difficult to manage conservatively. Fluoroscopically guided balloon dilation has a number of advantages and is a safe and effective procedure for the treatment of various benign anastomotic strictures in the UGI tract

In vivo genome editing with a small Cas9 orthologue derived from Campylobacter jejuni

Several CRISPR-Cas9 orthologues have been used for genome editing. Here, we present the smallest Cas9 orthologue characterized to date, derived from Campylobacter jejuni (CjCas9), for efficient genome editing in vivo. After determining protospacer-adjacent motif (PAM) sequences and optimizing single-guide RNA (sgRNA) length, we package the CjCas9 gene, its sgRNA sequence, and a marker gene in an all-in-one adeno-associated virus (AAV) vector and produce the resulting virus at a high titer. CjCas9 is highly specific, cleaving only a limited number of sites in the human or mouse genome. CjCas9, delivered via AAV, induces targeted mutations at high frequencies in mouse muscle cells or retinal pigment epithelium (RPE) cells. Furthermore, CjCas9 targeted to the Vegfa or Hif1a gene in RPE cells reduces the size of laser-induced choroidal neovascularization, suggesting that in vivo genome editing with CjCas9 is a new option for the treatment of age-related macular degeneration.

Tolerability and Outcomes of First-Line Pemetrexed-Cisplatin Followed by Gefitinib Maintenance Therapy Versus Gefitinib Monotherapy in Korean Patients with Advanced Nonsquamous Non-small Cell Lung Cancer: A Post Hoc Descriptive Subgroup Analysis of a Randomized, Phase 3 Trial

Purpose We recently reported on a randomized, open-label, phase 3 trial comparing pemetrexedcisplatin chemotherapy followed by gefitinib maintenance therapy (PC/G) with gefitinib monotherapy in patients with non-small cell lung cancer (NSCLC). Here, we report on a post hoc subgroup analysis of that study assessing the demographics and disposition of the Korean patient subgroup, and comparing the tolerability of PC/G and gefitinib monotherapy and the tumor response with respect to epidermal growth factor receptor (EGFR) status. Materials and Methods Patients, who were 18 years, chemonalve, Korean, light ex-smokers/never-smokers with advanced NSCLC, were randomly assigned (1:1) to PC/G or gefitinib monotherapy. Treatment-emergent adverse events (TEAEs) were graded, and tumor response was measured as change in lesion sum from baseline at best response. The study was registered with ClinicalTrials.gov, NCT01017874. Results Overall, 111 Korean patients were treated (PC/G, 51; gefitinib, 60). Between-arm characteristics were balanced and similar to those of the overall population. Treatment discontinuations due to adverse events were low (PC/G: 1, 2.0%; gefitinib: 7, 11.7%). Overall, 92 patients (82.9%) reported >= 1 TEAE (PC/G, 44; gefitinib, 48); few patients (PC/G, 16; gefitinib, 7) reported severe TEAEs; the most frequent was neutropenia (PC/G arm) and elevated alanine aminotransferase (gefitinib arm). The lesion sum was decreased by PC/G treatment in most patients, regardless of EGFR mutation status, while gefitinib monotherapy reduced the lesion sum in EGFR-positive patients but had no effect in EGFR-negative patients. Conclusion Our results confirm that both PC/G and gefitinib were well tolerated in Korean patients, regardless of EGFR status; however, patients with EGFR wild-type NSCLC may not benefit from gefitinib monotherapy.

Osimertinib in Patients with T790M-Positive Advanced Non-small Cell Lung Cancer: Korean Subgroup Analysis from Phase II Studies

Purpose Osimertinib is a third-generation, irreversible, oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that potently and selectively inhibits both EGFR sensitizing mutation and EGFR T790M and has demonstrated efficacy in non-small cell lung cancer (NSCLC) central nervous system (CNS) metastases. We present results of a subgroup analysis of Korean patients from the pooled data of two global phase II trials: AURA extension (NCT01802632) and AURA2 (NCT02094261). Materials and Methods Enrolled patients had EGFR T790M-positive NSCLC and disease progression during or after EGFR-TKI therapy. Patients received osimertinib 80 mg orally once daily until disease progression. The primary endpoint was objective response rate (ORR). Results In total, 66 Korean patients received osimertinib treatment with a median treatment duration of 19 months. In the evaluable-for-response population (n=62), ORR was 74% (95% confidence interval [CI], 61.5 to 84.5) and median duration of response was 9.8 months (95% CI, 7.1 to 16.8). In the full analysis set (n=66), median progression-free survival was 10.9 months (95% CI, 8.3 to 15.0; data cutoff November 1, 2016), and median overall survival was 29.2 months (95% CI, 24.8 to 35.7; data cutoff May 1, 2018). Eight patients with CNS metastases were evaluable for response, none of whom showed CNS progression. The most common adverse events were rash (53%), cough (33%), paronychia, diarrhea, and decreased appetite (each 32%). Conclusion Efficacy and safety profiles of osimertinib in this subgroup are consistent with the global phase II pooled population, which supports osimertinib as a recommended treatment for Korean patients with T790M positive NSCLC.