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In this paper, a novel, to the best of our knowledge, polymer-based negative curvature ring-core fiber (NC-RCF) is proposed and investigated. The hollow-core NC-RCF is composed of TOPAS as background material. The inner and outer negative curvature structure layers are connected to the annular area, and the orbital angular momentum (OAM) modes can propagate in the annular core. In the frequency region of 1.0–1.5 THz, the designed NC-RCF can stably transmit 82 OAM modes. Investigation results indicate that the effective refractive index differences between the corresponding HE and EH modes are above 10 − 4 . The confinement losses of EH or HE modes are smaller than 10 − 8 d B / m , and the dispersion variations are lower than 0.31 ps/THz/cm. Effective mode areas are larger than 5.14 m m 2 . Additionally, the highest mode purity of all vector modes is 99.78%. In addition, modal birefringence, also known as the walk-off length, has also been discussed. All these operation performances indicate that the designed NC-RCF make contributions to the optical communication systems.

Aging is a progressive decline of physiological function in tissue and organ accompanying both accumulation of DNA damage and reduction of non-coding DNA. Peripheral non-coding DNA/heterochromatin has been proposed to protect the genome and centrally-located protein-coding sequences in soma and male germ cells against radiation and the invasion of exogenous nucleic acids. Therefore, this review summarizes the reduction of non-coding DNA/heterochromatin (including telomeric DNA and rDNA) and DNA damage accumulation during normal physiological aging and in various aging-related diseases. Based on analysis of data, it is found that DNA damage accumulation is roughly negatively correlated with the reduction of non-coding DNA and therefore speculated that DNA damage accumulation is likely due to the reduction of non-coding DNA protection in genome defense during aging. Therefore, it is proposed here that means to increase the total amount of non-coding DNA and/or heterochromatin prior to the onset of these diseases could potentially better protect the genome and protein-coding DNA, reduce the incidence of aging-related diseases, and thus lead to better health during aging.

A multifunctional design based on vanadium dioxide (VO2) metamaterial structure is proposed. Broadband absorption, linear-to-linear (LTL) polarization conversion, linear-to-circular (LTC) polarization conversion, and total reflection can be achieved based on the insulator-to-metal transition (IMT) of VO2. When the VO2 is in the metallic state, the multifunctional structure can be used as a broadband absorber. The results show that the absorption rate exceeds 90% in the frequency band of 2.17 - 4.94 THz, and the bandwidth ratio is 77.8%. When VO2 is in the insulator state, for the incident terahertz waves with a polarization angle of 45°, the structure works as a polarization converter. In this case, LTC polarization conversion can be obtained in the frequency band of 0.1 - 3.5 THz, and LTL polarization conversion also can be obtained in the frequency band of 3.5 - 6 THz, especially in the 3.755 - 4.856 THz band that the polarization conversion rate is over 90%. For the incident terahertz waves with a polarization angle of 0°, the metamaterial structure can be used as a total reflector. Additionally, impacts of geometrical parameters, incidence angle and polarization angle on the operating characteristics have also been investigated. The designed switchable multifunctional metasurfaces are promising for a wide range of applications in advanced terahertz research and smart applications.

A novel method to detect the defect location and corrosion degree of petroleum pipelines by microwave is proposed in this paper. Three hypotheses are set in the simulation experiment: (a) intact oil pipeline; (b) corrosive oil pipeline; (c) broken oil pipeline. Among them, the flawed oil pipelines are divided into different grades according to different defect depths in the experiment. The probe is scanned on the pipe, and then the waveform of the scattering parameter (S11) is simulated. When the curve fluctuates, it means that the pipeline at the fluctuating place is incomplete, and can classify defects according to the amplitude of fluctuations (degree of corrosion). From the experimental results, we can discover that microwave technology can be used to accurately locate and classify the defects of an oil pipeline.

In this paper we introduce, for the first time in the literature, an optimized multistage symmetric two-step method. This method is considered as optimized due to the following reasons: (1) it is of tenth-algebraic order scheme, (2) it has obliterated the phase-lag and its first, second, third and fourth derivatives, (3) it has improved stability characteristics, (4) it is a P-stable method. For the new proposed multistage symmetric two-step method we present a full theoretical investigation consisted of: (1) local truncation error and comparative error analysis, (2) stability analysis and (3) interval of periodicity analysis. The effectiveness of the new builded multistage symmetric two-step method is evaluated on the solution of systems of coupled differential equations of the Schrodinger type.

Haemophilus parasuis (H. parasuis) is the etiological agent of swine Glasser's disease, which leads to significant economic loss in swine industry over the world. Subunit vaccine based on outer membrane protein is one of the promising choices to protect pigs against H. parasuis infection despite low immunity efficiency. In this paper, outer membrane protein 16 (Omp16) of H. parasuis encapsulated by alginate-chitosan microspheres as antigen carriers was explored for the first time in a mouse model. Our results showed that the microspheres with Omp16 induced significant higher H. parasuis-specific antibodies, and higher titers of IL-2, IL-4, and IFN-γ than those by Omp16-FIA in treated mice (p

The tumor suppressor DLEC1 has been shown to promote cell proliferation when AP-2α2 is down-regulated in HCT116 stable clones, suggesting its pro-survival nature. However, the pro-survival function of DLEC1 has not been confirmed in other cells and its underlying mechanisms remain elusive. Therefore, we knocked down DLEC1 in a panel of cell lines and found that DLEC1 depletion caused various extents of cell death through intrinsic pathway. DLEC1 overexpression promoted cell survival and reduced cell death in cancer cells after 5-FU treatment, while DLEC1 down-regulation sensitized cancer cells to 5-FU. Further studies demonstrated that DLEC1 attenuated the increase in cleaved PARP, caspase-3 and caspase-7, the activity of caspase-9 and the diffusion of cytosolic cytochrome c from mitochondria. Our data also showed that BCL-XL was up-regulated by DLEC1 in stable clones after 5-FU treatment. Altogether, these results indicated that DLEC1 protects cells against cell death induced by 5-FU through the attenuation of active proteins in caspase cascade and the up-regulation of BCL-XL. Therefore, DLEC1 can be a pro-survival protein under certain circumstances and a potential therapeutic target for increasing sensitivity of cancer cells to 5-FU.

Extrachromosomal circular DNA (eccDNA) accumulates within the nucleus of eukaryotic cells during physiological aging and in age-related diseases (ARDs) and the accumulation could be caused by the declined exclusion of nuclear eccDNA in these states. This review focuses on the formation of eccDNA and the roles of some main factors, such as nuclear pore complexes (NPCs), nucleoplasmic reticulum (NR), and nuclear actin, in eccDNA exclusion. eccDNAs are mostly formed from non-coding DNA during DNA damage repair. They move to NPCs along nuclear actin and are excluded out of the nucleus through functional NPCs in young and healthy cells. However, it has been demonstrated that defective NPCs, abnormal NPC components and nuclear actin rods are increased in aged cells, various cancers and certain other ARDs such as cardiovascular diseases, premature aging, neurodegenerative diseases and myopathies. Therefore, mainly resulting from the increase of dysfunctional NPCs, the exclusion of nuclear eccDNAs may be reduced and eccDNAs thus accumulate within the nucleus in aging and the aforementioned ARDs. In addition, the protective function of non-coding DNA in tumorigenesis is further discussed.

In this paper, a modified version of the turtle-shell data hiding (TDH) scheme is proposed, aiming at improving the quality of stego-image. TDH scheme was first proposed by Chang et al. in 2014. In comparison to other schemes at that time, the scheme exhibited a superior visual quality in the premise of ensuring high embedding capacity (EC). However, in the TDH scheme proposed by Chang et al., the rules to seek for the search space of the hiding message suffers the drawbacks of omitting the better alternative pixel pair. The scheme proposed in this paper modifies the embedding rule by allowing the selection of a proper region than the search space proposed by Chang et al., so as to better hide data and minimise the image distortion. According to the experimental results with the same EC, the visual quality of the stego-image in the proposed method is 0.41 dB higher than that of stego-image in Chang et al.'s method.

—In this paper, a remote closed-loop agricultural monitoring system based on the Internet of things and artificial intelligence decision-making was presented. It introduces two innovations: 1. through the ZigBee wireless sensor networking module, the collected field environment information data is sent to the ARM main controller. This sensor data will be converted into complied with TCP/IP protocol data types in the main controller and send to the cloud server for storage and processing furtherly, thus can conveniently access the server to manage and know the growth status of flowers through multiple types of the smart terminal. A mixed ad-hoc network data perception system not only reduces the reliance on the electric wire but also improves system reliability and usage range. 2. smart compensated light technology used in this system can accelerate plant growth by using photosynthesis to match different red-blue light ratios that can achieve maximum growth points. The system in this paper realizes the remote monitoring and control and multi-mode management of flower plants.

Information hiding, also known as data hiding, is an emerging field that combines multiple theories and technologies. In recent years, Chang et al. and Liu et al. have proposed new data hiding schemes based on Sudoku, a turtle-shell, etc. These proposed schemes have their own advantages in terms of visual quality and embedded capacity. However, the reference matrices used in these schemes are not optimal. Based on the characteristics of these schemes, Jin et al. employed particle swarm optimisation to select the reference matrix and achieved approximately optimal results in reducing the distortion of the stego-image. However, the complexity is high. In this paper, a turtle-shell matrix optimisation scheme is proposed using a greedy algorithm. The experimental results show that our proposed greedy algorithm is better than the particle swarm optimisation scheme at finding a near-optimal matrix and achieving better stego-image quality, and it outperforms the particle swarm optimisation scheme in terms of computational amount and efficiency.

Peripheral and abundant noncoding DNA has been hypothesized to protect the genome and the central protein-coding sequences against DNA damage in somatic genome. In the cytosol, invading exogenous nucleic acids may first be deactivated by small RNAs encoded by noncoding DNA via mechanisms similar to the prokaryotic CRISPR-Cas system. In the nucleus, the radicals generated by radiation in the cytosol, radiation energy and invading exogenous nucleic acids are absorbed, blocked and/or reduced by peripheral heterochromatin, and damaged DNA in heterochromatin is removed and excluded from the nucleus to the cytoplasm through nuclear pore complexes. To further strengthen the hypothesis, this review summarizes the experimental evidence supporting the protective function of noncoding DNA in the genome of male germ cells. Based on these data, this review provides evidence supporting the protective role of noncoding DNA in the genome defense of sperm genome through similar mechanisms to those of the somatic genome.

Non-coding DNA comprises a very large proportion of the total genomic content in higher organisms, but its function remains largely unclear. Non-coding DNA sequences constitute the majority of peripheral heterochromatin, which has been hypothesized to be the genome's 'bodyguard' against DNA damage from chemicals and radiation for almost four decades. The bodyguard protective function of peripheral heterochromatin in genome defense has been strengthened by the results from numerous recent studies, which are summarized in this review. These data have suggested that cells and/or organisms with a higher level of heterochromatin and more non-coding DNA sequences, including longer telomeric DNA and rDNAs, exhibit a lower frequency of DNA damage, higher radioresistance and longer lifespan after IR exposure. In addition, the majority of heterochromatin is peripherally located in the three-dimensional structure of genome organization. Therefore, the peripheral heterochromatin with non-coding DNA could play a protective role in genome defense against DNA damage from ionizing radiation by both absorbing the radicals from water radiolysis in the cytosol and reducing the energy of IR. However, the bodyguard protection by heterochromatin has been challenged by the observation that DNA damage is less frequently detected in peripheral heterochromatin than in euchromatin, which is inconsistent with the expectation and simulation results. Previous studies have also shown that the DNA damage in peripheral heterochromatin is rarely repaired and moves more quickly, broadly and outwardly to approach the nuclear pore complex (NPC). Additionally, it has been shown that extrachromosomal circular DNAs (eccDNAs) are formed in the nucleus, highly detectable in the cytoplasm (particularly under stress conditions) and shuttle between the nucleus and the cytoplasm. Based on these studies, this review speculates that the sites of DNA damage in peripheral heterochromatin could occur more frequently and may be removed by repetitive elements in non-coding DNA through the formation of eccDNAs and expelled out of the nucleus to the cytoplasm via the NPC. Therefore, this review proposes that the genome and central protein-coding sequences are doubly protected by non-coding DNA in peripheral heterochromatin against DNA damage from radiation, which may be a novel protective role of non-coding DNA in genome defense.

Traditionally, the genome has been described as the ‘book of life’. However, the metaphor of a book may not reflect the dynamic nature of the structure and function of the genome. In the eukaryotic genome, the number of centrally located protein-coding sequences is relatively constant across species, but the amount of noncoding DNA increases considerably with the increase of organismal evolutional complexity. Therefore, it has been hypothesized that the abundant peripheral noncoding DNA protects the genome and the central protein-coding sequences in the eukaryotic genome. Upon comparison with the habitation, sociality and defense mechanisms of a social insect colony, it is found that the genome is similar to a social insect colony in various aspects. A social insect colony may thus be a better metaphor than a book to describe the spatial organization and physical functions of the genome. The potential implications of the metaphor are also discussed.

As cellular models for in vitro liver cancer and toxicity studies, HepG2 and Hep3B are the two most frequently used liver cancer cell lines. Because of their similarities they are often treated as the same in experimental studies. However, there are many differences that have been largely over-sighted or ignored between them. In this review, we summarize the differences between HepG2 and Hep3B cell lines that can be found in the literature based on PubMed search. We particularly focus on the differential gene expression, differential drug responses (chemosensitivity, cell cycle and growth inhibition, and gene induction), signaling pathways associated with these differences, as well as the factors in governing these differences between HepG2 and Hep3B cell lines. Based on our analyses of the available data, we suggest that neither HBx nor p53 may be the crucial factor to determine the differences between HepG2 and Hep3B cell lines although HBx regulates the expression of the majority of genes that are differentially expressed between HepG2 and Hep3B. Instead, the different maturation stages in cancer development of the original specimen between HepG2 and Hep3B may be responsible for the differences between them. This review provides insight into the molecular mechanisms underlying the differences between HepG2 and Hep3B and help investigators especially the beginners in the areas of liver cancer research and drug metabolism to fully understand, and thus better use and interpret the data from these two cell lines in their studies.

On the basis of field environmental investigation and monitoring, the environmental radioactivity background of Xinchang and Jijicao rock in Beishan preselected region has been preliminary investigated and studied, and the public dose from local natural background radiation is estimated which can provide basic data and information for environmental impact assessment and safety assessment of HLW(the high level radioactive waste) disposal repository in the future. From the result of investigation and study, the environmental radioactivity of Xinchang and Jijicao rock is generally within normal natural background. The effective dose to local resident from natural background radiation is 2.110 mSv/a by internal and external exposure.

Based on BIOMASS methodology, FEPs analysis and data preparation, the biosphere model for Beishan, China (BIOMOBEIC) for performance assessment on high level radioactive waste(HLW) disposal repository has been developed by utilizing AMBER which is an efficient compartment modeling tool in order to evaluate dose rate to individual due to long-term release of nuclides from the HLW repository. From the result of mathematical simulation, the biosphere dose conversion factors (BDCFs) are obtained which are critical factors for conversion of release rates from the geosphere to individual doses in biosphere assessment and performance assessment.

The low level of knowledge management about research and development is greatly restricting China’s auto companies research and development ability. To solve this problem, the paper analyzes the actual demand of car research activities and constructs the enterprise research and development knowledge system in which knowledge map tool is the core, aiming at improving enterprise knowledge management level and car research and development ability.

To investigate the Terahertz's application prospect, corn, wheat husk and reed were used to detect their Terahertz Time Domain Spectroscopy, and be compared with that of cellulose powder. The experimental results show that all of their absorption peaks exist at 1.75, 1.62, 1.1, and 0.7 THz. Absorption intensity of cellulose powder, corn, wheat husk and reed were compared in some frequencies points. It finds that corn, wheat husk and reed have higher absorption intensity than cellulose powder in early frequency domain. However, absorption intensity of cellulose powder is the strongest at 1.62 THz. Cellulose content in corn, wheat husk and reed were detected by using the method of chemical analysis. The peaks of absorption coefficient are related to their cellulose content at this frequency. It shows that plant cellulose occur lattice vibration in the frequency. Deformation, bending, flexing, and other changes appear to their functional keys. Quantum chemical calculation was carried out by using density functional theory to cellulose and the structure diagram of cellulose molecular formula was obtained. It also finds some absorption peaks exist at 0.7, 1.1, and 1.75 THz. Characterization of cellulose clusters mainly includes CH2, OH, CH, and so on. Glucose hydroxyl radical on the ring is active in the cellulose chain. Where hydroxyl related chemical reaction can occur, Hydroxyl can also be integrated into the intermolecular and intramolecular hydrogen bond. Terahertz wave can promote hydrogen bond vibration. This kind of vibration is weak in the intermolecular interaction. The vibration and rotating happen in dipole transition. The crystal lattice rotates and is absorptive in low frequency, and large molecular skeleton vibrates. All of them can show different intensity and position of the absorption peak in the terahertz band. Corn and cellulose were analyzed by infrared spectrum. The reverse and vibration mode of cellulose was discussed. The absorption peak is basically in line with its theoretical calculating result. It is feasible that Terahertz Time Domain Spectroscopy can detect cellulose, and it provides a new method for the detection and judgement of cellulose in plants.

Nonviral vectors present considerable advantages over viral counterparts in gene transfer. However, the poor expression efficiency of the transfected genes poses a challenge for their use in gene therapy, primarily due to the inability of these vectors to overcome various barriers, including the biological barriers. Here, we report that ZNF511-PRAP1 may be involved in the recognition and inactivation of transfected plasmids. ZNF511-PRAP1 is induced by transfection of plasmid DNA and suppresses the transcription of transfected plasmids. It binds directly to the p21 promoter in transfected plasmids but not the endogenous counterpart. Similarly, ZNF511-PRAP1 suppresses the expression of the green fluorescent protein reporter gene on transiently transfected plasmids but not an integrated red fluorescence reporter gene with the same cytomegalovirus (CMV) promoter. Therefore, ZNF511-PRAP1 is able to differentiate between exogenous/nonintegrated and endogenous/integrated DNA. The suppression by ZNF511-PRAP1 is independent of DNA methylation and can be abolished by trichostatin A (TSA) treatment and knockdown of HDAC2 and/or ZNF511-PRAP1. Furthermore, ZNF511-PRAP1 interacts directly with HDAC2. Our results revealed that transfected plasmids are recognized by ZNF511-PRAP1 and suppressed by a repressor complex comprising ZNF511-PRAP1 and HDAC2 and suggest that ZNF511-PRAP1 could play a role as a potential molecular barrier in nonviral transgene expression.

Background/Aims The chromosome locus 3p21.3 is a "hot-spot" for chromosomal aberrations and loss of heterozygosity in cancers. The 35 genes mapped to the AP20 subregion of this locus were screened for their expression to identify candidate tumor suppressor genes. DLEC1 was selected for further characterization in primary hepatocellular carcinomas and cell lines. Methods RT-PCR and methylation-specific PCR were performed to examine the expression and methylation. Stable clones with DLEC1 overexpression were established to analyze cell proliferation and cell cycle. Results DLEC1 was silenced and hypermethylated in 9 of 11 cell lines examined. Treatment with 5-aza-2′-deoxycytidine reversed the methylation and restored DLEC1 expression. The correlation between hypermethylation and expression was also demonstrated in 10 pairs of hepatocellular carcinoma and adjacent normal tissues ( t -test, p DLEC1 was detected in 70.6% of tumors, compared to 10.3% in normal tissues ( n =68, p χ 2 ). Of interest, DLEC1 methylation was associated with the AJCC staging of the tumors ( p =0.036, χ 2 ). DLEC1 over-expression in cell lines decreased colony formation, cell growth and cell size, and induced a G1 arrest in cell cycle. Conclusions Our data indicate that DLEC1 is a candidate tumor suppressor gene that plays an important role in the development and progression of hepatocellular carcinoma.

Background The molecular mechanisms of tumor suppressor gene DLEC1 are largely unknown. Objectives In this study, we established DLEC1 over-expression stable clones to study the cellular function of DLEC1 in the colorectal cancer cell line, HCT116. Materials and methods Stable clones with DLEC1 over-expression were first established by the transfection of DLEC1 expression construct pcDNA31DLEC1 in HCT116. On G418 selection, positive stable clones were screened for DLEC1 expression level by conventional reverse transcription-polymerase chain reaction (RT-PCR), and verified by real-time RT-PCR and Western blotting. Subsequently, these stable clones were subjected to colony formation and cell cycle analyses and identification of factors involved in G1 arrest. Lastly, three stable clones, DLEC1-7 (highest DLEC1 expression), DLEC1-3 (lowest expression) and pcDNA31 vector control, were employed to analyze cell proliferation and cell cycle after AP-2α2 knockdown by siRNAs. Results The DLEC1 over-expression was found to reduce the number of colonies in colony formation and to induce G1 arrest in seven clones, and apoptosis in one clone in the cell cycle analysis. Furthermore, regardless of the different cell cycle defects in all eight stable clones, the expression level of transcriptional factor AP-2α2 was found to be elevated. More interestingly, we found that when AP-2α2 was knocked down, DLEC1 over-expression neither suppressed cancer cell growth nor induced G1 arrest, yet, instead promoted cell growth and decreased cells in the G1 fraction. This promotion of cell proliferation and release of G1 cells also seemed to be proportional to DLEC1 expression levels in DLEC1 stable clones. Conclusions DLEC1 suppresses tumor cell growth the presence of AP-2α2 and stimulates cell proliferation in the down-regulation of AP-2α2 in DLEC1 over-expression stable clones of HTC116.

In this review, the protective function of the abundant non-coding DNA in the eukaryotic genome is discussed from the perspective of genome defense against exogenous nucleic acids. Peripheral non-coding DNA has been proposed to act as a bodyguard that protects the genome and the central protein-coding sequences from ionizing radiation-induced DNA damage. In the proposed mechanism of protection, the radicals generated by water radiolysis in the cytosol and IR energy are absorbed, blocked and/or reduced by peripheral heterochromatin; then, the DNA damage sites in the heterochromatin are removed and expelled from the nucleus to the cytoplasm through nuclear pore complexes, most likely through the formation of extrachromosomal circular DNA. To strengthen this hypothesis, this review summarizes the experimental evidence supporting the protective function of non-coding DNA against exogenous nucleic acids. Based on these data, I hypothesize herein about the presence of an additional line of defense formed by small RNAs in the cytosol in addition to their bodyguard protection mechanism in the nucleus. Therefore, exogenous nucleic acids may be initially inactivated in the cytosol by small RNAs generated from non-coding DNA via mechanisms similar to the prokaryotic CRISPR-Cas system. Exogenous nucleic acids may enter the nucleus, where some are absorbed and/or blocked by heterochromatin and others integrate into chromosomes. The integrated fragments and the sites of DNA damage are removed by repetitive non-coding DNA elements in the heterochromatin and excluded from the nucleus. Therefore, the normal eukaryotic genome and the central protein-coding sequences are triply protected by non-coding DNA against invasion by exogenous nucleic acids. This review provides evidence supporting the protective role of non-coding DNA in genome defense.

Loss of heterozygosity at 3p21 is common in various cancers including nasopharyngeal carcinoma (NPC). BLU is one of the candidate tumor suppressor genes (TSGs) in this region. Ectopic expression of BLU results in the inhibition of colony formation of cancer cells, suggesting that BLU is a tumor suppressor. We have identified a functional BLU promoter and found that it can be activated by environmental stresses such as heat shock, and is regulated by E2F. The promoter and first exon are located within a CpG island. BLU is highly expressed in testis and normal upper respiratory tract tissues including nasopharynx. However, in all seven NPC cell lines examined, BLU expression was downregulated and inversely correlated with promoter hypermethylation. Biallelic epigenetic inactivation of BLU was also observed in three cell lines. Hypermethylation was further detected in 19/29 (66%) of primary NPC tumors, but not in normal nasopharyngeal tissues. Treatment of NPC cell lines with 5-aza-2'-deoxycytidine activated BLU expression along with promoter demethylation. Although hypermethylation of RASSF1A, another TSG located immediately downstream of BLU, was detected in 20/27 (74%) of NPC tumors, no correlation between the hypermethylation of these two TSGs was observed (P=0.6334). In addition to methylation, homozygous deletion of BLU was found in 7/29 (24%) of tumors. Therefore, BLU is a stress-responsive gene, being disrupted in 83% (24/29) of NPC tumors by either epigenetic or genetic mechanisms. Our data are consistent with the interpretation that BLU is a TSG for NPC.

ICF syndrome (immunodeficiency, centromere instability and facial anomalies) is a recessive human genetic disorder resulting from mutations in the DNA methyltransferase 3B (DNMT3B) gene. Patients with this disease exhibit numerous chromosomal abnormalities, including anomalous decondensation, pairing, separation and breakage, primarily involving the pericentromeric regions of chromosomes 1 and 16. Global levels of DNA methylation in ICF cells are only slightly reduced; however, certain repetitive sequences and genes on the inactive X chromosome of female ICF patients are significantly hypomethylated. In the present report, we analyze the molecular defect of de novo methylation in ICF cells in greater detail by making use of a model Epstein-Barr virus (EBV)-based system and three members of the unique cellular cancer-testis (C-T) gene family. Results with the EBV-based system indicate that de novo methylation of newly introduced viral sequences is defective in ICF syndrome. Limited de novo methylation capacity is retained in ICF cells, indicating that the mutations in DNMT3B are not complete loss-of-function mutations or that other DNMTs cooperate with DNMT3B. Analysis of three C-T genes (two on the X chromosome and one autosomal) revealed that loss of methylation from cellular gene sequences is heterogeneous, with both autosomal and X chromosome-based genes demonstrating sensitivity to mutations in DNMT3B. Aberrant hypomethylation at a number of loci examined correlated with altered gene expression levels. Lastly, no consistent changes in the protein levels of the DNA methyltransferases were noted when normal and ICF cell lines were compared.

In this study, an object contour extraction using local structure information (LSI) captured by tri-directional spotlight (TDSL) filter is proposed. The proposed TDSL filter is designed by using three directional spotlight filters with overlapping areas in capturing local structure information around a discontinuity along object contour. The TDSL filter for object contour extraction is consisted of three steps. First, the TDSL filter is placed on an initial contour point to calculate the local structure information in determining and storing the edge candidates between any two pre-selected initial contour points. Next, edge points with weak evidence will be filtered out to obtain an object contour wideband. By performing a thinning approach on the object contour wideband image, a closed one-pixel-width object contour will be finally obtained. Experimental results of the proposed method for manmade and real medical images exhibit that the proposed TDSL filter can enhance the accuracy of contour detection and extraction much better than other existing methods for object contour extraction.

A retrospective study was conducted to investigate the clinical features and prognostic factors of 73 cases of severe hepatitis.To summarize clinical features of 73 cases of severe hepatitis, grouping by etiology and pathogenesis. A retrospective analysis was performed to evaluate the relationship between biochemical characteristics (liver function, renal function, electrolytes, PTA, etc) and complications (hepatic encephalopathy, upper gastrointestinal bleeding, hepatorenal syndrome, ascites, abdominal infections, etc) and prognosis.(1) HBV infection alone accounted for 65.75%. Alcoholic liver disease, drug-induced liver injury, hepatitis E, autoimmune hepatitis, overlapping causes and other factors were five cases (6.85%), six cases (8.22%), two cases (2.74%), two cases (2.74%), seven cases (9.59%) and three cases (4.11%) respectively. According to the incidence rate, severity and underlying liver condition, subacute hepatitis, cases based on chronic hepatitis and on cirrhosis were 12 cases (16.43%), 11 cases (15.07%), 50 cases (68.49%) respectively. Clinical manifestations with or without hepatic encephalopathy accounted for 58.90% or 41.10%. (2) The highest mortality of severe hepatitis was alcoholic liver disease and patients on the basis of overlapping factors (66.67%), followed by autoimmune liver disease (50%). The mortality of HBV-related hepatitis was 18.75%. Overall mortality of 73 cases of severe hepatitis was 28.77%, of which cirrhosis group was higher than non-cirrhotic group (40% vs 4.3%, P = 0.002). The difference was statistically significant. Patients without hepatic encephalopathy had lower mortality than with hepatic encephalopathy (3.33% vs 46.51%). The mortality of patients with hepatic encephalopathy Stage III and IV was 72.73%. (3) Independent samples t test filtered nine factors associated with death, namely cirrhosis, upper gastrointestinal bleeding, hepatic encephalopathy, hepatorenal syndrome, serum creatinine, total bilirubin (TBIL), direct bilirubin (DBIL), albumin (ALB) and serum sodium. The results of multivariate conditional logistic regression analysis indicated that hepatic encephalopathy, serum creatinine levels were risk factors for death, whereas ALB as a protective factor.Hepatic encephalopathy, serum creatinine levels were risk factors for severe hepatitis death, But ALB was protective factor. Nucleotide analogs using was the main reason why the mortality of hepatitis B was as low as 18.75%.

To explore the etiology of acute hepatitis hospitalized patients in Beijing Ditan Hospital from 2002 to 2011.We summed up the changes in the characteristics of the etiology of acute hepatitis of patients mentioned above, and preliminarily analyze the causes.From 2002 to 2011, 6235 patients with acute hepatitis were admitted to Ditan Hospital, aged between 12 and 78 years old, Of which 4309 were male and 1926 female. Acute viral hepatitis accounted for 70.44%-85.07%, while CMV, EBV, drug-induced liver injury accounted less than 5%, and acute hepatitis D and acute hepatitis C less than 1.10%. From year to year, the incidence and constitution of acute hepatitis changed significantly. The proportion of patients with acute hepatitis in total hospitalized patients was from 20. 38% to 2.05%. In 10 years, the percentage of acute hepatitis A decreased most obviously, about 99.11%, while 45.07% decline in incidence of acute hepatitis B and 62. 28% of acute hepatitis E. The constituent ratio of acute hepatitis also changed significantly. The proportion of acute hepatitis A declined from 31.31% in 2002, to less than 1% in 2011. The proportion of acute hepatitis B increased from 26.47% in 2002 to 45.88% in 2011, an increase of about 2 folds in 10 years. The proportion of acute hepatitis E increased from 26.73% in 2002 to 32.05% in 2010, a rise of 1.20 times in 10 years.The proportion of patients with acute hepatitis in total hospitalized patients decreased from 20. 38% in 2002 to 2. 05% in 2011 in Beijing Ditan Hospital. The constituent ratio of acute hepatitis changed, too.

To explore the effect of intensive treatment for refractory chronic hepatitis C, and to improve the sustained viral response (SVR) rate of treatment with interferon plus ribavirin by optimizing therapeutic dose and course.Patients who did not acquire response or partial response by standard therapy (PEG-IFN alpha subcutaneous injection weekly plus Ribavirin 10.5 mg/kg) every day were enrolled and retreated with intensive treatment of 10 MU interferon every other day or 360 microg pegylated interferon alpha-2a weekly according to patients' wishes, and ribavirin 15 mg/kg every day. Serum HCV RNA was detected at baseline,treatment week 4, 12 and every 12 weeks succedent and 24 weeks after treatment end. Course of treatment was 72 to 96 weeks according to viral response. SVR was the mark of therapeutic effect.18 patients completed whole range therapy and follow-up, in which 12 patients acquired SVR, 5 patients treatment failure and 1 relapse. 3 patients acquired rapid viral response (RVR), and they all got complete Early Viral Response (cEVR) and SVR. RVR Patients' viral loads were significantly lower than that of patients who did not acquire RVR (t = 4. 687, P0.001). In 15 patients who did not acquire RVR, 8 patients acquired cEVR, and 9 acquired SVR. SVR rate of patients who were administered PEG-IFN alpha-2a was 4/5, 11 patients who acquired cEVR all acquired SVR, while in 7 patients who did not acquire cEVR, only 1 patient acquired SVR.High percent patients, who did not acquire response or partial response by previous standard antiviral therapy, could gain SVR by intensive dose interferon plus Ribavirin. In intensive treatment procedure, adjusting and prolonging course according to viral response after HCV RNA turned negative were important measures to improve refractory Chronic Hepatitis C SVR rate.

To explore the retreatment of CHC patients with initial treatment failure and how to achieve SVR.54 patients who had experienced treatment failure were enrolled and retreated with standard treatment of pegylated interferon and ribavirin or intensive treatment, respectively. Their SVR rates were statistically compared, to decide two therapies' application.54 patients had been retreated, and total SVR rate was up to 75.92%, with 88.46% in relapsed patients and 64.29% in non-responders. After retreatment with pegylated interferon and ribavirin, SVR rate was 95.45% in patients with prior interferon monotherapy, and 64.71% in patients with prior interferon and ribavirin, and 60% in patients with prior pegylated interferon alpha-2a monotherapy. SVR rate of relapsed patients was significantly higher than that of non-responders.In CHC patients with treatment failure, SVR rate of retreatment with standard treatment or intensive treatment still can be up to 60%-90%. Retreatment with standard therapy can be applied to patients who had received interferon monotherapy or interferon plus ribavirin. Three types of patients who need intensive retreatment were as following: patients nonresponsive to interferon plus ribavirin or pegylated interferon alpha-2a monotherapy, and patients with treatment failure who had received prior standard treatment.

To study the clinical features, outcomes and treatments of viral hepatitis combined with aplastic anemia.25 cases diagnosed as viral hepatits combined with aplastic anemia in Beijing Ditan Hsopital between April 2004 and September 2009 were retrospectively analyzed. In this group of patients aplastic anemia was finally diagnosed by bone marrow aspiration. We collected clinical data of these patients, including a history of liver disease, drug allergies, hospital medication history, laboratory data, and then performed descriptive analysis.25 patients with viral hepatitis were diagnosed as complicated with aplastic anemia by histopathological data. Among these patients, 17 were male and 8 were women. Viral hepatitis included: chronic hepatitis B (12 cases), chronic hepatitis C (4 cases), acute hepatits E (1 case), hepatitis caused by CMV infection (1 case), and unclassified hepatitis (7 cases). Among these patients, 7 were diagnosed as severe hepatits. Considering previous history, only 3 patients had history of short term interferon therapy before hospitalization, and the remaining patients did not use drug that affects blood system. Treatments were as followings: using colony stimulating factor in 6 patients, gamma globulin in 9 patients, glucocorticoids in 3 patients, erythropoietin in 1 patient, only oral drug to raise erythrocytes in 2 patients, red blood cells transfusion in 6 patients, platelets transfusion in 2 patients. As for clinical outcomes, 20 patients acquired improved condition and were dicharged, 3 patients were discharged voluntarily and 2 patients died of severe hepatits combined with other complications.Main treatments of viral hepatitis combined with aplastic anemia were to treat primary hepatopathy and nucleoside analogue-based antiviral therapy, to provide symptomatic and supportive treatment for blood diseases. Blood diseases would recover simultaneously while liver disease was improved, and the prognosis was good.

To investigate the relation of serum HBsAg, HBeAg contents and HBV-DNA load changes in HBeAg-positive chronic hepatitis B during IFN-alpha treatment.After enrolled, the patients were treated with 3MU-5MU IFN subcutaneous injection every two days, and their serum was collected before treatment and every 3 months during the treatment course. The serum HBV-DNA load was determined by real-time fluorescence quantitative PCR method kit (lower detection limit 500 copies/ml, Piji company, Shenzhen city, China,) according to production instruction, and HBeAg and HBsAg contents were detected by ARCHITECH I 2000.chemiluminescent kit. The relation of serum HBV-DNA, HBeAg and HBsAg content was analyzed by SPSS statistic software.There were 228 patients enrolled into this group, male 162 cases, female 66 cases, aged 14-60 years, average 30.94 years old. After IFN treatment the HBV-DNA, HBeAg and HBsAg levels were all gradually decreased. But there was no relation of HBsAg content to HBV DNA and HBeAg content before and during treatment course(P0.05). However the serum HBeAg content was related to HBV-DNA content significantly (P0.05) and their changes was correspondence.Before and during treatment of interferon, HBeAg and HBV-DNA content changes are closely related, while there is no significant correlation between HBsAg and HBeAg and HBV-DNA content. During interferon therapy, HBsAg, HBeAg, HBV-DNA contents should be detected together.

HBsAg loss and seroconversion in patients with chronic hepatitis B leads to long-lasting good clinical outcomes. The aim of this paper was to investigate to improve the rate of HBsAg loss and seroconversion in chronic hepatitis B patients by prolonged treatment of PEG-IFNa-2a. 217 cases of HBeAg-positive or negative patients were collected from inpatient and outpatient in Beijing Ditan Hospital from May 2005 to October 2009 and subcutaneous injection of 135 ug or 180 ug PEGASYS were given once a week according to body weights. The drug doses were adjusted according to the neutrophilic granulocyte and platelet counts during treatment course. Quantitative HBV DNA test was conducted using a commercially available real-time fluorescence quantitative PCR kit. The serum HBsAg/anti-HBs and HBeAg/anti-HBe were quantitatively detected by Abbott i 2000 chemiluminescent kit before and during treatment every three months. Patients with HBsAg steadily decreased and reached serum HBsAg level below 200 IU/ml after 48 weeks of treatment would receive prolonged treatment. Patients with more than 12 weeks of treatment entered into analysis. Main efficacy of prolonged treatment was evaluated by the incidences of HBsAg loss and seroconversion.The treatment courses of the 217 patients ranged from 12.0 to 197.6 weeks with an average of 53.1+/-33.4 weeks, 118 cases took more than 48 weeks and another 89 cases less than 48 weeks. 13.4% (29/217) of patients achieved HBsAg loss or HBsAg seroconversion with treatment courses from 17.6 to 197.6 weeks (average 75.4+/-42.8 weeks). Among these 29 patients 24 (82.8%) received more than 48 weeks of treatment, but the treatment courses of HBV DNA reached undetectable level were 20.8+/-8.9 weeks. In this study, 9.5% (14/148) of HBeAg-positive patients achieved HBsAg loss or seroconversion, all of them treated more than 48 weeks, from 48 to 194 weeks, average 81.32+/-39.36 weeks. 21.7% (15/69) of HBeAg-negative patients achieved HBsAg loss or seroconversion, significantly higher than that of HBeAg-positive patients (9.5%) (x2 = 6.129, P = 0.013). The average treatment course for HBeAg-negative patients with HBsAg loss was 70.2+/-48.0 weeks, shorter than that of HBeAg-positive patients with HBsAg loss (81.3+/-39.4 weeks), but no significant difference (t = -0.522, P = 0.602) found between.Higher rate of HBsAg loss and seroconversion could be obtained by individual extended treatment courses in patients with rapid HBV DNA and HBsAg response to PEG-IFNa-2a treatment and the HBeAg-negative patients could got higher rate of HBsAg loss than HBeAg-positive patients.

To evaluate whether the rapid viral response (RVR) to combinational therapy with interferon and rabavirin can be used to predict the sustained viral response (SVR) in chronic hepatitis C patients.According to their clinical characteristics, all patients in this study were given pegylated or conventional interferon injection and different dose of ribavirin according to their weight. Patients were injected Pegasys (pegierferon alpha-2a) 180 microg or 135 microg once a week, or pegyintron 50-80 microg once a week, or conventional interferon 3-5 MU every two days, in combination with a dose of 600-1500 mg/d ribavirin. The serum HCV RNA load was determined at 0, 4, 12 week, and then every 12 weeks. After the viral response obtained, the patients were treated for another 24-72 weeks and followed up 24 weeks. The main parameter to evaluate the efficacy was SVR rate. The influence factors associated with rapid viral response were investigated.RVR was obtained at week 4 in 84.2% of the 120 patients. The HCV RNA baseline of RVR group was (5.883+/-1.246) lg copies/ml, which was significantly lower than that of the group without RVR [(6.502+/-0.693) lg copies/ml, t=2.15, P=0.034]. 97 patients with RVR who finished treatment and follow-up, 90.7% of these patients obtained SVR, but the SVR rate in patients (82.4%) without RVR was lower than that in patients with RVR (x2=0.371, P=0.543). In this study, RVR rate was not associated with HCV genotype and the dose of interferon used. In the naive patients, the RVR to pegylated interferon was 87.8%, which was significantly higher than that in retreat patients (x2=4.651, P=0.031).High RVR rate could be obtained in chronic hepatitis C patients treated combined with interferon and ribavirin. RVR rate is associated with the HCV RNA baseline load in both naive and retreat patients but not correlated to HCV genotype. RVR could predict the SVR.

Background/Aims hDAB2IP is a candidate tumor suppressor gene. We studied the expression of its two variants, hDAB2IPA and hDAB2IPB , in normal tissues, and the expression and methylation status of hDAB2IPA in hepatocellular carcinomas (HCC) and cell lines. Methods Conventional or real-time RT-PCR was performed in normal tissue samples, cell lines and HCC samples, and sequencing analysis and methylation-specific PCR in cell lines and HCC samples. Results hDAB2IPA was the predominant isoform, being expressed in the majority of tissues examined. The expression of hDAB2IPA was silenced or down-regulated but could be restored by 5-aza-2′-deoxycytidine treatment in liver cancer cell lines. The reactivation of hDAB2IPA was associated with promoter demethylation. The correlation between promoter methylation and hDAB2IPA expression was confirmed in eight pairs of matched HCC samples. Further, the methylation of the hDAB2IPA promoter in HCC was confirmed in an additional 53 pairs of patient samples. More than 80% of HCC samples showed hDAB2IPA promoter methylation, compared to 11.5% in the corresponding adjacent normal tissue ( p χ 2 ). Conclusions Our data suggest that hDAB2IPA is the dominant isoform expressed in normal tissues. Its expression is suppressed in HCC, consistent with its role as a tumor suppressor gene, mainly by promoter methylation.

3p21 is an important locus harbouring critical tumour suppressor genes (TSG), which are implicated in the pathogenesis of multiple tumours, including oesophageal carcinoma. RASSF1A is a 3p21.3 candidate TSG frequently inactivated by promoter methylation in multiple tumours. We investigated RASSF1A promoter methylation and gene expression in Chinese oesophageal squamous cell carcinoma (ESCC) to compare it to data from Japanese patients. Methylation-specific PCR (MSP) showed that RASSF1A was partially methylated in 3/7 (43%) cell lines; 22/64 (34%) primary tumours and 3/64 (5%) corresponding non-tumour samples; and was not methylated in 2 immortalized normal oesophageal epithelial cell lines and 6 normal oesophageal epithelium samples. Bisulfite genome sequencing confirmed the MSP results. Promoter hypermethylation correlated well with RASSF1A mRNA down-regulation. Treatment of cell lines with 5-aza-2'-deoxycytidine activated RASSF1A mRNA expression along with promoter demethylation. RASSF1A hypermethylation in the Chinese cohort was much lower than in a published report of Japanese ESCC patients (52%) and cell lines (74%). Our own analysis of Japanese ESCC cell lines for direct comparison also detected a high frequency of RASSF1A hypermethylation (8/10; 80%) and high levels of hypermethylation at each CpG site. No significant association between RASSF1A hypermethylation and histological differentiation (p=0.953), tumour staging (p=0.117), or survival (p=0.7571) was found in Chinese ESCC, unlike the results of Japanese patients. The incidence of oesophageal cancer shows marked variation by geographic area and ethnic group; it is almost three times higher in China than in Japan, indicating possible different pathogenetic mechanisms. Our results show that RASSF1A hypermethylation in ESCC has epidemiological/ethnic differences, and suggest that Chinese ESCC may result from different pathogenetic mechanisms.

In order to fully understand hepatitis c virus (HCV) genotype 3b, 1a, 2b and 6a infection in China, We built HCV 5'-noncoding region (5'-NCR) of different genotypes and subtypes.The classification HCV into variable genotypes (subtypes) was carried on by programs A, B and C A. Using a combination of three restriction endonuclease BHH' (BsrB I, Hae II, Hinf I) digestions at the same time. The distinct genotypes were classified into 5 groups: genotype 1 (1a, 1b), 6a, 2 (2a, 2b), genotype 3 (3a, 3b), genotype4 (4a). B. With regard to genotype 1, we could distinguish subtype 1a from 1b using BstU I digestion. C. Using restriction endonuclease Hae III, genotype 2a, 2b, 3b, 4a, 6a are differentiated respectively.(1) HCV genotype 1a, 1b, 2a, 2b, 3a, 3b, 4a, 6a are fully discriminated by comparison with the genotypes regular samples. (2) Of the 93 patients, HCV genotype distribution in China was 66.67% for 1b, 18.28% for 2a, 3.23% for 1b/2b, 3b, 2b respectively. 2.15% for 2a/2b, 1b/2a respectively. 1.08% for 1a.This research indicated that adoption of HCV 5'-NCR A B C restriction endonuclease digestions techniques, might be sensitive and efficient to detect HCV and discriminate HCV genotype (subtypes) 1a to 6a.