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Plants' response to pathogens is highly complex and involves changes at different levels, such as activation or repression of a vast array of genes. Recently, many studies have demonstrated that many RNAs, especially small RNAs (sRNAs), are involved in genetic expression and reprogramming affecting plant–pathogen interactions. The sRNAs, including short interfering RNAs and microRNAs, are noncoding RNA with 18–30 nucleotides, and are recognized as key genetic and epigenetic regulators. In this review, we summarize the new findings about defence‐related sRNAs in the response to pathogens and our current understanding of their effects on plant–pathogen interactions. The main content of this review article includes the roles of sRNAs in plant–pathogen interactions, cross‐kingdom sRNA trafficking between host and pathogen, and the application of RNA‐based fungicides for plant disease control. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effect of zoledronic acid (ZA) on human umbilical vein endothelial cells (HUVECs) attached to different surfaces. Materials and Methods: A total of three groups were evaluated in this study: sandblasting and acid etching (SLA) + HUVECs; mechanically polished (MP) + HUVECs; and plastic cell culture plates + HUVECs. Scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, surface roughness and water contact angle were tested for titanium surface characterisation. ZA was added at different concentrations (0, 1, 10, 50 and 100 μM). Cell adhesion, proliferation, viability, apoptosis and gene expression were evaluated. Results: Mechanically polished and SLA surfaces showed negative effects on cell adhesion and proliferation and promoted cell apoptosis with 100 μM ZA (p <.05). The highest expression of intercellular adhesion molecule‐1 (ICAM‐1) and angiopoietin‐1 was found on SLA surfaces (p <.01). The lowest expression of platelet‐endothelial cell adhesion molecule‐1 and ICAM‐1 was found on MP surfaces (p <.05). A significant decrease in von Willebrand factor was detected on MP and SLA surfaces (p <.001). Conclusions: Zoledronic acid has an anti‐angiogenic effect on HUVECs attached to titanium implants, while the SLA surface might stimulate HUVECs to express angiogenic and adhesive factor genes despite ZA treatment. [ABSTRACT FROM AUTHOR]

Background: OCT4, SOX2, and NANOG are major transcription factors related to stem cell self-renewal and differentiation. The aim of this study was to examine the association of OCT4, SOX2, and NANOG expression levels with the development and prognosis of patients with oral squamous cell carcinoma (OSCC). Materials and Methods: Expression levels of OCT4, SOX2, and NANOG were evaluated by immunohistochemistry with tissue microarray slides of 436 OSCC, 362 corresponding tumor-adjacent normal (CTAN) tissues, and 71 normal uvula epithelium tissues. The clinicopathologic and follow-up data of the OSCC patients were recorded. Results: OCT4 expression was significantly higher in normal and CTAN tissues than in tumor tissue (both P < 0.001). SOX2 expression in CTAN tissue was significantly higher than that in normal (P = 0.021) and tumor tissues (P < 0.001). However, NANOG expression was significantly higher in CTAN (P = 0.014) and tumor tissues (P = 0.009) than in normal tissue. Higher OCT4 and SOX2 expressions were associated with earlier AJCC stage (P = 0.002 and P < 0.001), small tumor size (P = 0.017 and P = 0.001), and the absence of lymph node metastasis (P = 0.015 and P = 0.025). Higher levels of SOX2 expression were associated with better disease-specific survival (P = 0.002) even after adjustment for clinicopathologic factors. Discussion: OCT4 and SOX2 are biomarkers of tumorigenesis and early stage OSCC. SOX2 is an independent prognostic factor for OSCC. [ABSTRACT FROM AUTHOR]

The expression of the chemorepellent Sema3a is inversely related to sympathetic innervation. We investigated whether overexpression of Sema3a in the myocardial infarction ( MI) border zone could attenuate sympathetic hyper-innervation and decrease the vulnerability to malignant ventricular tachyarrhythmia ( VT) in rats. Survived MI rats were randomized to phosphate buffered saline ( PBS, n = 12); mock lentivirus ( MLV, n = 13) and lentivirus-mediated overexpression of Sema3a ( SLV, n = 13) groups. Sham-operated rats served as control group ( CON, n = 20). Cardiac function and electrophysiological study ( PES) were performed at 1 week later. Blood and tissue samples were collected for histological analysis, epinephrine ( EPI), growth-associated factor 43 ( GAP43) and tyrosine hydroxylase ( TH) measurements. QTc intervals were significantly shorter in SLV group than in PBS and MLV groups (168.6 ± 7.8 vs. 178.1 ± 9.5 and 180.9 ± 8.2 ms, all P < 0.01). Inducibility of VT by PES was significantly lower in the SLV group [30.8% (4/13)] than in PBS [66.7% (8/12)] and MLV [61.5% (8/13)] groups ( P < 0.05). mRNA and protein expressions of Sema3a were significantly higher and the protein expression of GAP43 and TH was significantly lower at 7 days after transduction in SLV group compared with PBS, MLV and CON groups. Myocardial EPI in the border zone was also significantly lower in SLV group than in PBS and MLV group (8.73 ± 1.30 vs. 11.94 ± 1.71 and 12.24 ± 1.54 μg/g protein, P < 0.001). Overexpression of Sema3a in MI border zone could reduce the inducibility of ventricular arrhythmias by reducing sympathetic hyper-reinnervation after infarction. [ABSTRACT FROM AUTHOR]

The impact of angiotensin II receptor blockers (ARBs) on electrical remodelling after myocardial infarction (MI) remains unclear. The purpose of the present study was to evaluate the effect of valsartan on incidence of ventricular arrhythmia induced by programmed electrical stimulation (PES) and potential link to changes of myocardial connexins (Cx) 43 expression and distribution in MI rats. Fifty-nine rats were randomly divided into three groups: Sham ( n = 20), MI ( n = 20) and MI + Val (20 mg/kg/day per gavage, n = 19). After eight weeks, the incidence of PES-induced ventricular tachycardia (VT) and fibrillation (VF) was compared among groups. mRNA and protein expressions of Cx43, angiotensin II type 1 receptor (AT1R) in the LV border zone (BZ) and non-infarct zone (NIZ) were determined by real-time PCR and Western blot, respectively. Connexins 43 protein and collagen distribution were examined by immunohistochemistry in BZ and NIZ sections from MI hearts. Valsartan effectively improved the cardiac function, reduced the prolonged QTc (163.7 ± 3.7 msec. versus 177.8 ± 4.5 msec., P < 0.05) after MI and the incidence of VT or VF evoked by PES (21.1% versus 55%, P < 0.05). Angiotensin II type 1 receptor expression was significantly increased in BZ and NIZ sections after MI, which was down-regulated by valsartan. The mRNA and protein expressions of Cx43 in BZ were significantly reduced after MI and up-regulated by valsartan. Increased collagen deposition and reduced Cx43 expression in BZ after MI could be partly attenuated by Valsartan. Valsartan reduced the incidence of PES-induced ventricular arrhythmia, this effect was possibly through modulating the myocardial AT1R and Cx43 expression. [ABSTRACT FROM AUTHOR]

Despite increasing interest in the molecular mechanisms of floral diversity, few studies have investigated the developmental and genetic bases of petaloid bracts. This study examined morphological patterns of bract initiation and expression patterns of B-class MADS-box genes in bracts of several Cornus species. We suggest that petaloid bracts in this genus may not share a single evolutionary origin., Developmental pathways of bracts and spatiotemporal expression of B-class genes in bracts and flowers were examined for four closely related dogwood species., Divergent morphological progressions and gene expression patterns were found in the two sister lineages with petaloid bracts, represented by Cornus florida and Cornus canadensis. Phylogeny-based analysis identified developmental and gene expression changes that are correlated with the evolution of petaloid bracts in C. florida and C. canadensis., Our data support the existence of independent evolutionary origins of petaloid bracts in C. canadensis and C. florida. Additionally, we suggest that functional transference within B-class gene families may have contributed to the origin of bract petaloidy in C. florida. However, the underlying mechanisms of petaloid bract development likely differ between C. florida and C. canadensis. In the future this hypothesis can be tested by functional analyses of Cornus B-class genes. [ABSTRACT FROM AUTHOR]