Clinical Value of CD24 Expression in Retinoblastoma

Background. The expression of CD24 has been detected in a wide variety of human malignancies. Downregulation of CD24 inhibits proliferation and induces apoptosis in tumor cells, whereas its upregulation increases tumor growth and metastasis. However, no data on CD24 protein levels in retinoblastoma are available, and the mechanism of CD24 involvement in retinoblastoma progress has not been elucidated. The aim of this study was to explore the expression profile of CD24 in the retinoblastoma tumor samples and to correlate with clinicopathological parameters. Methods. Immunohistochemistry was performed for CD24 on the archival paraffin sections of retinoblastoma and correlated with clinicopathological features. Western blotting was performed to confirm immunoreactivity results. Results. CD24 immunoreactivity was observed in 72.0% (36/50) of the retinoblastoma specimens. Among the 35 low-risk tumors, CD24 was expressed in 62.9% (22/35) tumors and among the 15 high-risk tumors, CD24 was expressed in 93.3% (14/15) tumors. High-risk tumors showed significantly increased expression of CD24 compared to tumors with low-risk (P < 0.05). Conclusions. This is the first correlation between CD24 expression and histopathology in human retinoblastoma. Our study showed increased expression of CD24 in high risk tumors compared to low risk tumors. Further functional studies are required to explore the role of CD24 in retinoblastoma

Cell type-specific characterization of nuclear DNA contents within complex tissues and organs

BACKGROUND: Eukaryotic organisms are defined by the presence of a nucleus, which encloses the chromosomal DNA, and is characterized by its DNA content (C-value). Complex eukaryotic organisms contain organs and tissues that comprise interspersions of different cell types, within which polysomaty, endoreduplication, and cell cycle arrest is frequently observed. Little is known about the distribution of C-values across different cell types within these organs and tissues. RESULTS: We have developed, and describe here, a method to precisely define the C-value status within any specific cell type within complex organs and tissues of plants. We illustrate the application of this method to Arabidopsis thaliana, specifically focusing on the different cell types found within the root. CONCLUSION: The method accurately and conveniently charts C-value within specific cell types, and provides novel insight into developmental processes. The method is, in principle, applicable to any transformable organism, including mammals, within which cell type specificity of regulation of endoreduplication, of polysomaty, and of cell cycle arrest is suspected

Wireless capsule endoscopy exploration for diseases of the small intestine in China

For small bowel diseases, it is difficult for the ordinary enteroscopy to reach due to its specific curvature and length. Capsule endoscopy (CE) is a unique tool to visualize the mucosa of the small intestine. The aim of this study was to evaluate the detection rate and diagnostic yield of CE in a large group of patients with suspected digestive diseases in China. One hundred and two consecutive patients (75 male, mean age 50 years, range 32-87 years) underwent CE in our Gastroenterology Units, for a total of 102 procedures. Referrals were obscure occult/ overt gastrointestinal bleeding group (19 patients) and suspected small bowel disease group (83). In our study, the whole detection rate was 92 % (94/102), with a definite diagnosis yield of 63 % of the patients in the obscure gastrointestinal bleeding and 39 % of the patients in the suspected small bowel diseases. None of the patients developed symptoms of signs of mechanical obstruction, although the capsule was retained in the stomach in 2/102 patients for their somatostatin taken. CE seems to be a very safe, painless and effective procedure with a high diagnostic yield. Accurate selection of indications and critical evaluation of the results are essential to explore these diseases

A mutation degree model for the identification of transcriptional regulatory elements

<p>Abstract</p> <p>Background</p> <p>Current approaches for identifying transcriptional regulatory elements are mainly via the combination of two properties, the evolutionary conservation and the overrepresentation of functional elements in the promoters of co-regulated genes. Despite the development of many motif detection algorithms, the discovery of conserved motifs in a wide range of phylogenetically related promoters is still a challenge, especially for the short motifs embedded in distantly related gene promoters or very closely related promoters, or in the situation that there are not enough orthologous genes available.</p> <p>Results</p> <p>A mutation degree model is proposed and a new word counting method is developed for the identification of transcriptional regulatory elements from a set of co-expressed genes. The new method comprises two parts: 1) identifying overrepresented oligo-nucleotides in promoters of co-expressed genes, 2) estimating the conservation of the oligo-nucleotides in promoters of phylogenetically related genes by the mutation degree model. Compared with the performance of other algorithms, our method shows the advantages of low false positive rate and higher specificity, especially the robustness to noisy data. Applying the method to co-expressed gene sets from Arabidopsis, most of known <it>cis</it>-elements were successfully detected. The tool and example are available at <url>http://mcube.nju.edu.cn/jwang/lab/soft/ocw/OCW.html</url>.</p> <p>Conclusions</p> <p>The mutation degree model proposed in this paper is adapted to phylogenetic data of different qualities, and to a wide range of evolutionary distances. The new word-counting method based on this model has the advantage of better performance in detecting short sequence of <it>cis</it>-elements from co-expressed genes of eukaryotes and is robust to less complete phylogenetic data.</p

Structure and function of pancreatic lipase-related protein 2 and its relationship with pathological states

Pancreatic lipase is critical for the digestion and absorption of dietary fats. The most abundant lipolytic enzymes secreted by the pancreas are pancreatic triglyceride lipase (PTL or PNLIP) and its family members, pancreatic lipase-related protein 1 (PNLIPRP1or PLRP1) and pancreatic lipase-related protein 2 (PNLIPRP2 or PLRP2). Unlike the family\u27s other members, PNLIPRP2 plays an elemental role in lipid digestion, especially for newborns. Therefore, if genetic factors cause gene mutation, or other factors lead to non-expression, it may have an effect on fat digestion and absorption, on the susceptibility to pancreas and intestinal pathogens. In this review, we will summarize what is known about the structure and function of PNLIPRP2 and the levels of PNLIPRP2 and associated various pathological states

Synthesis of a Novel Ce-bpdc for the Effective Removal of Fluoride from Aqueous Solution

Ce-1,1′-biphenyl-4,4′-dicarboxylic acid (Ce-bpdc), a novel type of metal organic framework, was synthesized and applied to remove excessive fluoride from water. The structure and morphology of Ce-bpdc were measured by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The effects, such as saturated adsorption capacity, HCO3-, and pH, were investigated. The optimal pH value for fluoride adsorption was the range from 5 to 6. The coexisting bicarbonate anions have a little influence on fluoride removal. The fluoride adsorption over the Ce-bpdc adsorbent could reach its equilibrium in about 20 min. The Ce-bpdc coordination complex exhibited high binding capacity for fluoride ions. The maximum adsorption capacity calculated from Langmuir model was high up to 45.5 mg/g at 298 K (pH = 7.0) and the removal efficiency was greater than 80%. In order to investigate the mechanism of fluoride removal, various adsorption isotherms such as Langmuir and Freundlich were fitted. The experimental data revealed that the Langmuir isotherm gave a more satisfactory fit for fluoride removal. Finally, the tested results of ground water samples from three places, Yuefang, Jiangji, and Sanyi which exhibited high removal efficiency, also demonstrate the potential utility of the Ce-bpdc as an effective adsorbent

Deep sequencing discovery of novel and conserved microRNAs in trifoliate orange (Citrus trifoliata)

<p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs) play a critical role in post-transcriptional gene regulation and have been shown to control many genes involved in various biological and metabolic processes. There have been extensive studies to discover miRNAs and analyze their functions in model plant species, such as <it>Arabidopsis </it>and rice. Deep sequencing technologies have facilitated identification of species-specific or lowly expressed as well as conserved or highly expressed miRNAs in plants.</p> <p>Results</p> <p>In this research, we used Solexa sequencing to discover new microRNAs in trifoliate orange (<it>Citrus trifoliata</it>) which is an important rootstock of citrus. A total of 13,106,753 reads representing 4,876,395 distinct sequences were obtained from a short RNA library generated from small RNA extracted from <it>C. trifoliata </it>flower and fruit tissues. Based on sequence similarity and hairpin structure prediction, we found that 156,639 reads representing 63 sequences from 42 highly conserved miRNA families, have perfect matches to known miRNAs. We also identified 10 novel miRNA candidates whose precursors were all potentially generated from citrus ESTs. In addition, five miRNA* sequences were also sequenced. These sequences had not been earlier described in other plant species and accumulation of the 10 novel miRNAs were confirmed by qRT-PCR analysis. Potential target genes were predicted for most conserved and novel miRNAs. Moreover, four target genes including one encoding IRX12 copper ion binding/oxidoreductase and three genes encoding NB-LRR disease resistance protein have been experimentally verified by detection of the miRNA-mediated mRNA cleavage in <it>C. trifoliata</it>.</p> <p>Conclusion</p> <p>Deep sequencing of short RNAs from <it>C. trifoliata </it>flowers and fruits identified 10 new potential miRNAs and 42 highly conserved miRNA families, indicating that specific miRNAs exist in <it>C. trifoliata</it>. These results show that regulatory miRNAs exist in agronomically important trifoliate orange and may play an important role in citrus growth, development, and response to disease.</p

The catalytic core of DEMETER guides active DNA demethylation in Arabidopsis.

The Arabidopsis DEMETER (DME) DNA glycosylase demethylates the maternal genome in the central cell prior to fertilization and is essential for seed viability. DME preferentially targets small transposons that flank coding genes, influencing their expression and initiating plant gene imprinting. DME also targets intergenic and heterochromatic regions, but how it is recruited to these differing chromatin landscapes is unknown. The C-terminal half of DME consists of 3 conserved regions required for catalysis in vitro. We show that this catalytic core guides active demethylation at endogenous targets, rescuing dme developmental and genomic hypermethylation phenotypes. However, without the N terminus, heterochromatin demethylation is significantly impeded, and abundant CG-methylated genic sequences are ectopically demethylated. Comparative analysis revealed that the conserved DME N-terminal domains are present only in flowering plants, whereas the domain architecture of DME-like proteins in nonvascular plants mainly resembles the catalytic core, suggesting that it might represent the ancestral form of the 5mC DNA glycosylase found in plant lineages. We propose a bipartite model for DME protein action and suggest that the DME N terminus was acquired late during land plant evolution to improve specificity and facilitate demethylation at heterochromatin targets