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Quantitative real-time polymerase chain reaction (qRT-PCR) is a sensitive and widely used technique for quantifying gene expression levels, and its accuracy depends on the reference genes used for data normalization. To date, no reference gene has been reported in the nutritious and functional vegetable okra (Abelmoschus esculentus L.). Herein, 11 candidates of reference genes were selected and evaluated for their expression stability in okra in different tissues at different developmental stages by using three software algorithms (geNorm, NormFinder, BestKeeper) and a web-based tool (RefFinder). Among them, eukaryotic initiation factor 4 alpha (eIF4A) and protein phosphatase 2A (PP2A) showed the highest stability, while TUA5 had the lowest stability. The combined usage of these two most stable reference genes was sufficient to normalize gene expression in okra. Then, the above results were further validated by normalizing the expression of the cellulose synthase gene CesA4. This work provides appropriate reference genes for transcript normalization in okra, which will facilitate subsequent functional gene research on this vegetable crop. [ABSTRACT FROM AUTHOR]

Background: The long noncoding RNA HOTAIR (HOX transcript antisense intergenic RNA) has been reported to be a biomarker for various malignant tumors; however, its involvement in breast cancer is not fully understood. The aim of this study was to investigate the effects involved with long noncoding RNA HOTAIR and EZH2 (enhancer of zeste homologue 2) on the processes of proliferation, invasion, migration, and apoptosis of breast cancer cells.Materials and Methods: The expressions of HOTAIR and EZH2 in both normal human mammary epithelial cell (HBL-100) and breast cancer cell lines (MCF-7, MDA-MB-231, and SKBR-3) were detected by means of reverse transcription-quantitative polymerase chain reaction. The MCF-7 cells that exhibited the highest HOTAIR expressions were selected for further studies and divided into the control, negative control, and small interfering RNA-HOTAIR groups. The proliferation, invasion, migration, and apoptosis of breast cancer cells were evaluated by MTT assay, Scratch test, Transwell assay, and flow cytometry, respectively. The combination of HOTAIR with EZH2 and PTEN was predicted by bioinformation, with a dual-luciferase reporter gene assay providing further verification.Results: Initially, lower expressions of HOTAIR and EZH2 in the normal human mammary epithelial cells, while higher expressions in the breast cancer cells of MCF-7, MDA-MB-231, and SKBR-3 were detected. In addition, the downregulation of HOTAIR or silencing of EZH2 was revealed to repress the proliferation, invasion, and migration, while acting to promote the apoptosis of the breast cancer cells. Furthermore, HOTAIR could bind specifically to EZH2 and PTEN, highlighting the capability of HOTAIR to inhibit the expression of PTEN by recruiting EZH2 in breast cancer, while the TCGA database demonstrated the expressions of PTEN were lower in breast cancer cells.Conclusions: The study suggests the higher expressions of HOTAIR and EZH2 among three breast cancer cells. Furthermore, the downregulation of HOTAIR or silencing of EZH2 was noted to inhibit the proliferation, invasion, and migration of breast cancer cells, while promoting their apoptosis. [ABSTRACT FROM AUTHOR]

We have successfully developed an integrated microsystem that combines two plastic microchips for DNA extraction and PCR amplification with a glass capillary array electrophoresis chip together in a compact control and detection instrument for automated forensic short tandem repeat (STR) analysis. DNA extraction followed by an “in situ PCR” was conducted in a single reaction chamber of the microchip based on a filter paper-based extraction methodology. PCR products were then mixed with sizing standards by an injection electrode and injected into the electrophoresis chip for four-color confocal fluorescence detection. The entire STR analysis can be completed in about two hours without any human intervention. Since the 15-plex STR system has a more stringent requirement for PCR efficiency, we optimized the structure of the plastic DNA extraction and amplification chip, in which the reaction chamber was formed by sandwiching a hollow structure layer with two blank cover layers, to reduce the adsorption of PCR reagents to the surfaces. In addition, PCR additives, bovine serum albumin, poly(ethylene glycol), and more magnesium chloride were included into the on-chip multiplex STR system. The limit-of-detection study demonstrated that our microsystem was able to produce full 15-plex STR profiles from 3.75 ng standard K562 DNA. Buccal swab and whole blood samples were also successfully typed by our system, validating the feasibility of performing rapid DNA typing in a “sample-in-answer-out” manner for on-site forensic human identification. [ABSTRACT FROM AUTHOR]

A fully integrated and automated microsystem consisting of low-cost, disposable plastic chips for DNA extraction and PCR amplification combined with a reusable glass capillary array electrophoresis chip in a modular-based format was successfully developed for warfarin pharmacogenetic testing. DNA extraction was performed by adopting a filter paper-based method, followed by “in situ” PCR that was carried out directly in the same reaction chamber of the chip without elution. PCR products were then co-injected with sizing standards into separation channels for detection using a novel injection electrode. The entire process was automatically conducted on a custom-made compact control and detection instrument. The limit of detection of the microsystem for the singleplex amplification of amelogenin was determined to be 0.625 ng of standard K562 DNA and 0.3 μL of human whole blood. A two-color multiplex allele-specific PCR assay for detecting the warfarin-related single-nucleotide polymorphisms (SNPs) 6853 (–1639G＞A) and 6484 (1173C＞T) in the VKORC1 gene and the *3 SNP (1075A＞C) in the CYP2C9 gene was developed and used for validation studies. The fully automated genetic analysis was completed in two hours with a minimum requirement of 0.5 μL of input blood. Samples from patients with different genotypes were all accurately analyzed. In addition, both dried bloodstains and oral swabs were successfully processed by the microsystem with a simple modification to the DNA extraction and amplification chip. The successful development and operation of this microsystem establish the feasibility of rapid warfarin pharmacogenetic testing in routine clinical practice. [ABSTRACT FROM AUTHOR]

In forensic genetic analyses, mixtures of various biological materials are common samples. Micromanipulation, which is performed based on differences in cellular morphology, is an effective method for the isolation of cells from mixtures. In this study, mucosal cell was isolated from somatic cellular mixtures (blood and saliva) based on micromanipulation and a low volume- PCR ( LV- PCR) platform. One hundred and twenty-six parallel LV- PCR processes were performed using an Identifiler® kit, with 107 reactions yielding single-source DNA profiles. Among them, 54 full profiles (50%) and 37 partial profiles (13-15 loci) were obtained. Based on the above method, we obtained a single-source DNA profile from a cigarette butt contaminated by two victims' blood in a murder case. The generated genotype was used to query a DNA database, and a perfect match was found. [ABSTRACT FROM AUTHOR]

Abstract: Glycyrrhiza uralensis licorice has long been used worldwide as a food additive and herbal medicine. It possesses a remarkable healing action on gastrointestinal ulcers. The present study was carried out to assess the effect of licorice on intestinal crypt cell proliferation and to investigate the corresponding molecular mechanism. Considering the role of crypt stem cells in intestinal mucosa repair, a well-established cytostatic cellular model, polyamine-depleted IEC-6 cells, was utilized to evaluate the effect of aqueous licorice on the proliferation of intestinal crypt cells. The growth inhibition of IEC-6 cells caused by alpha-difluoromethylornithine could be significantly reversed by concomitant treatment with 40 μg/ml and 80 μg/ml licorice aqueous extract. In particular, the restoration of cell cycle progression was accompanied by a decrease in p21 mRNA level and cytoplasmic accumulation of the RNA-binding protein HuR, which was shown to be involved in the destabilization of p21 mRNA. Using a biotin pull-down assay and a luciferase assay, it was found that licorice-modulated p21 mRNA expression was achieved by HuR-targeted AU-rich and U-rich elements that resided in the 3′ untranslated region of p21 mRNA. These results demonstrate that licorice can exert its action on stimulating the growth of intestinal crypt cells by regulating p21 mRNA level at the posttranscriptional level by HuR. [Copyright &y& Elsevier]