An IHS-Based Pan-Sharpening Method for Spectral Fidelity Improvement Using Ripplet Transform and Compressed Sensing

Pan-sharpening aims at integrating spectral information from a multi-spectral (MS) image and spatial information from a panchromatic (PAN) image in a fused image with both high spectral and spatial resolutions. Numerous pan-sharpening methods are based on intensity-hue-saturation (IHS) transform, which may cause evident spectral distortion. To address this problem, an IHS-based pan-sharpening method using ripplet transform and compressed sensing is proposed. Firstly, the IHS transform is applied to the MS image to separate intensity components. Secondly, discrete ripplet transform (DRT) is implemented on the intensity component and the PAN image to obtain multi-scale sub-images. High-frequency sub-images are fused by a local variance algorithm and, for low-frequency sub-images, compressed sensing is introduced for the reconstruction of the intensity component so as to integrate the local information from both the intensity component and the PAN image. The specific fusion rule is defined by local difference. Finally, the inverse ripplet transform and inverse IHS transform are coupled to generate the pan-sharpened image. The proposed method is compared with five state-of-the-art pan-sharpening methods and also the Gram-Schmidt (GS) method through visual and quantitative analysis of WorldView-2, Pleiades and Triplesat datasets. The experimental results reveal that the proposed method achieves relatively higher spatial resolution and more desirable spectral fidelity.

[A retrospective analysis of clinical characteristics and outcomes of heart failure patients with different left ventricular ejection fractions]

Objective: To compare the clinical characteristics, and outcomes of patients with heart failure with different left ventricular ejection fractions (LVEF). Methods: A total of 1 182 hospitalized patients with heart failure (HF) were enrolled and retrospectively studied in the present study. The patients were stratified by LVEF as reduced (HFrEF, LVEF<40%, n=313), mid-range (HFmrEF, 40% ≤LVEF <50%, n=287) and preserved (HFpEF, LVEF≥50%, n=582) ejection fraction groups. Among the 1 182 cases, 941 of them (81.3%, 84.9%, and 84.0% inHFrEF, HFmrEF and HFpEF groups, respectively) were followed up for an median duration of 27.3 months. Results: (1) Among the study patients, 26.5% were in HFrEF, 24.3% in HFmrEF, and 49.2% in HFpEF groups. (2) Ischemic heart disease with HFmrEF was more frequent than that in patients with HFrEF. The average age, percentage of female subjects, systolic blood pressure, uric acid, N terminal B-type natriuretic peptide precursor (NT-proBNP), hemoglobin, and the incidence of hypertensive heart disease, anemia, atrial fibrillation in patients with HFmrEF were higher than those in patients with HFrEF, but lower than those in patients with HFpEF (all P<0.01). (3) The all-cause cumulative mortality was 10.8% at 1 year, 20.6% at 2 years and 35.9% at 5 years. No difference was observed in the all-cause cumulative mortality at 1 year, 2 years, 5 years among the three groups (all P>0.05). Conclusions: The HFmrEF patients, as a new and distinct group, were with many intermediate characteristics compared with HFrEF and HFpEF subjects. However, the all-cause mortality was not significantly different among HF patients with different LVEF.

Piccolo mediates EGFR signaling and acts as a prognostic biomarker in esophageal squamous cell carcinoma

The presynaptic cytomatrix protein Piccolo, encoded by PCLO, is frequently mutated and amplified in esophageal squamous cell carcinoma (ESCC), but its exact roles in ESCC remain unclear. Here we report that Piccolo expression correlates significantly with clinical stage, patient survival and tumor embolus. Functional studies demonstrate that PCLO knockdown remarkably attenuates ESCC malignancy in vitro and in vivo, and ectopic EGFR expression partially compensates for Piccolo loss. PCLO knockdown promotes ubiquitination and degradation of EGFR, which is associated with the negative regulatory effect of Piccolo on E3 ligase Siah1. An anti-Piccolo monoclonal antibody inhibited tumor proliferation in a mouse model of ESCC. These results demonstrate that Piccolo contributes to tumor aggressiveness in ESCC, likely by stabilizing EGFR and promoting EGFR-dependent signaling. Our results further suggest that Piccolo may represent a novel prognostic biomarker and therapeutic target for patients with ESCC.

Upregulation of long noncoding RNA ZEB1-AS1 promotes tumor metastasis and predicts poor prognosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide. Despite progress in diagnostics and treatment of HCC, its prognosis remains poor. Emerging studies showed that long noncoding RNAs (lncRNAs) have crucial regulatory roles in cancer biology. In the current study, differentially expressed lncRNAs between HCC and paired non-tumor tissues were identified using microarrays. The effects of a specific differentially expressed lncRNA (termed ZEB1-AS1) on tumor progression were investigated in vitro and in vivo. We found that ZEB1-AS1 is frequently upregulated in HCC samples, especially in metastatic tumor tissues. DNA methylation analysis shows a tumor-specific ZEB1-AS1 promoter hypomethylation. Aberrant methylation is tightly correlated with overexpression of ZEB1-AS1 in HCC. Patients with ZEB1-AS1 hypomethylation or with high ZEB1-AS1 expression have poor recurrence-free survival. Functionally, ZEB1-AS1 promotes tumor growth and metastasis, acts as an oncogene in HCC. The ZEB1-AS1 gene is located in physical contiguity with ZEB1 and positively regulates the ZEB1 expression. ZEB1 inhibition partially abrogates ZEB1-AS1-induced epithelial to mesenchymal transition (EMT) and cancer metastasis. Our results provide novel insights into the function of lncRNA-driven hepatocarcinogenesis, highlight the important role of ZEB1-AS1 and ZEB1 in HCC progression, and indicate that ZEB1-AS1 may be served as a valuable prognostic biomarker for HCC.

Platelet-activating factor receptor-mediated PI3K/AKT activation contributes to the malignant development of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies worldwide and occurs at a relatively high frequency in China, yet the mechanisms underlying its devastating outcome remain unclear. Here we report that platelet-activating factor receptor (PAFR), a type of G-protein-coupled receptor, was upregulated in ESCC tumors and cell lines, compared with controls; PAFR levels were positively correlated with ESCC clinical stages and survival time. Overexpression of PAFR promoted the malignant development of ESCC in vitro and in vivo, whereas depletion of PAFR suppressed these effects. Interestingly, PAFR was observed to activate PI3K/AKT (phosphatidylinositol 3-kinase/AKT) through the upregulation of FAK kinase activity. AKT-triggered nuclear factor-κB transcriptionally activated PAFR expression. This mutual positive regulation between PAFR and AKT was required for the aggressiveness of ESCC cells both in vitro and in vivo. Furthermore, treating mice bearing ESCC tumors with cholesterol-conjugated PAFR small interfering RNA effectively inhibited tumor progression and the expression of AKT-mediated oncogenic proteins. Taken together, we made the first demonstration that dysregulation of PAFR and the positive regulatory loop between PAFR and pAKT contribute to malignant progression of ESCC.

A case-control study indicates that the TRIB1 gene is associated with pancreatic cancer

Pancreatic cancer is a malignant neoplasm originating from transformed cells arising in tissues that form the pancreas. To investigate whether the tribbles homolog 1 (Drosophila) gene (TRIB1) is associated with pancreatic cancer in the Chinese Han population, we conducted this case-control study and genotyped 3 single nucleotide polymorphisms (rs2980879, rs2980874, and rs2235108) of the TRIB1 gene in 182 patients and 359 normal controls of Chinese Han origin and analyzed their association. The results showed that the rs2980879 polymorphism was associated with pancreatic cancer [allele: P = 0.023434, genotype: P = 0.03005; odds ratio (OR) and 95% confidence interval (CI) = 0.727788 (0.552664-0.958404)], whereas the rs2980874 polymorphism had no association with pancreatic cancer [allele: P = 0.749885, genotype: P = 0.699533; OR and 95%CI = 1.041981 (0.809196-1.341734)], and the rs2235108 polymorphism was not associated with the disease [allele: P = 0.629475, genotype: P = 0.547534, OR and 95%CI = 1.128290 (0.690829-1.842770)]. Haplotype analyses and linkage disequilibrium tests were also conducted, and the results showed that these 3 loci are not in the same block. In conclusion, our study indicated that the TRIB1 gene is associated with pancreatic cancer. More studies with larger samples are needed in order to support this finding.