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Surface plasmon polaritons (SPPs) are propagating waves generated at the interface of a metal (metamaterial) and a dielectric. The intensity of SPPs often exponentially decays away from the surface, while their wavelengths can be tuned by the confinement effect. We present here a computational method based on quantum-mechanical theory to fully describe the interaction between confined SPPs and adsorbed molecules at the interface. Special attention has been paid to the roles of the confinement factor. Taking a prototype dye sensitized solar cell as an example, calculated results reveal that with the increase in the confinement factor in metal/dielectric interfaces, the breakdown of the conventional dipole approximation emerges, which allows efficient harvesting of SPPs with low excitation energies and, thus, increases the efficiency of the solar energy conversion by dye molecules. Furthermore, at the metamaterial/dielectric interface, SPPs with large confinement factors could directly excite the dye molecule from its ground singlet state to the triplet state, opening an entirely new channel with long-living carriers for the photovoltaic conversion. Our results not only provide a rigorous theory for the SPP–molecule interaction but also highlight the important role played by the momentum of the light in plasmon related studies. [ABSTRACT FROM AUTHOR]

Liver cancer is a common tumor of digestive system. Hepatocellular carcinoma (HCC) is a common type of liver cancer, which has a high degree of malignancy and ranks among the top causes of cancer-related death in the world. Metabolic reprogramming is considered to be an important marker of carcinogenesis. Glucose metabolism is one of the main ways for cells to produce energy. Glycolysis, as the basic reaction of glucose metabolism, plays an important role in cell metabolism. Therefore, the regulation of glycolysis is of great significance to the proliferation and evolution of tumors. More and more non-coding RNAs (ncRNA) have been proved to play an important role in the regulation of tumor glycolysis. This article reviews the role of ncRNA in the regulation of HCC glycolysis and its related mechanisms. At the same time, the prospect of targeted therapy for HCC based on the related mechanisms of glycolysis regulation is put forward.

Objective: To observe the change in the amount of sialic acids on hepatocellular carcinoma (HCC) cell membrane., Methods: Surgical specimens of HCC and liver cirrhosis tissues were obtained from 28 patients to prepare carcinoma cell and hepatocyte suspensions by collagenase digestion. For assay of α2, 3 and α2, 6-sialic acids, the cells were suspended in the staining buffer containing either fluorescein isothiocyanate-Maackia amurensis lectin (FITC-MAL) or fluorescein isothiocyanate-Sambucus nigra bark lectin (FITC-SNA) and incubated for 1 h, respectively. Flow cytometric analysis was carried out to measure the mean fluorescence intensity (MFI) on the cell surface., Results: In both FITC-MAL- and FITC-SNA-incubated HCC cells, the MFI on the cell surface was greater than that of the hepatocytes., Conclusion: Both of α2, 3 and α2, 6- sialic acids increases significantly on the hepatocyte membrane after the carcinomatous change.

Objective: To evaluate the therapeutic effect of in vitro induced autologous bone marrow-derived liver stem cell transplantation for posthepatitic cirrhosis., Methods: Between Jun 2008 and Mar 2009, 12 patients with posthepatitic cirrhosis and portal hypertensive underwent azygousportal disconnection and splenectomy in our department. The patients were then divided into two groups to receive autologous bone marrow-deprived liver stem cell infusion via the hepatic artery after in vitro induction for 7 days (n=6) or saline (n=6). The therapeutic effects of the operations on the liver functions and liver fibrosis index were evaluated., Results: All the patients recovered uneventfully and no side effect of the operation was found. After the operation, the patients receiving bone marrow-deprived liver stem cell infusion showed better hepatic function improvement than those receiving saline infusion (P<0.05)., Conclusion: Transplantation of in vitro induced autologous bone marrow-derived liver stem cell via the hepatic artery is safe and effective for treatment of posthepatitic cirrhosis.

Objective: To explore practical protocols for cloning bone marrow-derived hepatic stem cells in vitro., Methods: The cell fraction rich in CD117(+) cells and CD184(+) cells was separated from fresh bone marrow by density gradient centrifugation and cultured for 0, 7 and 14 days in high-glucose DMEM supplemented with or without 10% autologous serum or in serum-free high-glucose DMEM. All the media were supplemented with different concentrations of hepatocyte growth promoting factors (HGPF), thrombopoietin (TPO) and interleukin-3 (IL-3). The quantitative changes of CD117(+) cells and CD184(+) cells were measured by flow cytometry., Results: The optimal effect for cell cloning was achieved with high-glucose DMEM with 10% autologous serum group supplemented with 40 microg/ml HGPF, 50 ng/ml TPO, and 10 ng/ml IL-3. At day 7 of cell culture in this media, the quantity of CD117(+) cells and CD184(+) cells increased by 6.55 and 6.20 folds, and by 11.62 and 20.57 folds at day 14, respectively., Conclusion: It is practical for cloning bone marrow-derived hepatic stem cells in high-glucose DMEM with 10% autologous serum supplemented with 40 microg/ml HGPF, 50 ng/ml TPO, and 10 ng/ml IL-3.

Currently used plant transformation systems require selectable marker genes encoding antibiotic or herbicide resistance, along with the gene of interest, to select transformed cells from a large population of mostly untransformed cells. The continued presence of these selectable markers, especially in food crop, is of increasing public concern. The generation of selectable marker-free transgenic plant is one of the new projects in plant biotechnology research. Two techniques, segregation excision and recombination excision, for removal of selectable marker genes are described in this article. The advances in producing selectable marker-free transgenic plants are reviewed too.

The genome of wheat rosette stunt virus (WRSV), a plant rhabdovirus, is a single negative strand RNA. It encodes five viral structural proteins: the glycoprotein (G), the matrix protein (M), the nucleocapsid protein (N), the large protein (L) and the non?structural protein (NS), which was later proved to be a viral structural protein too and existed in a variety of phosphorylation forms in case of vascular stomatitis virus (VSV). In this paper we demonstrated that NS protein of WRSV, either bound with the viral nucleocapsid or expressed in bacteria could be in vitro phosphorylated in presence of viral nucleocapsid. We concluded that the NS protein of WRSV was a phosphorylated protein and it might exist in both phosphorylated and dephosphorylated forms in virions. Our results excluded the possibility that the NS protein could be autophosphorylated. The L protein, the major component of viral RNA dependent RNA polymerase is associated with the protein kinase for phosphorylation of NS protein.

Rice ragged stunt oryzavirus (RRSV) is a member of the genus oryzavirus within the family Reoviridae. Its genome consists of ten segments of dsRNA. The functions of all products encoded by these viral genome segments, except one encoded by S9, have not yet been elucidated. In the present study, the ORF of S 8 of RRSV-Philippines isolate was sequenced and expressed in E. coli. The 67 kD product of S8 could be self-cleaved into two fragments with molecular weights of 43 kD and 26 kD. Western blotting indicated that both 67 kD and 43 kD products were major structural proteins of the virus. It was also found that the 67 kD protein could self aggregate into aggregates with higher sedimentation rate in sucrose gradients during centrifugation. Moreover, the self-aggregation process could be accelerated by the complex of S6 product and genome dsRNAs of RRSV. These results suggest that the S8 products, 67 kD or 43 kD, may be the structural components of the viral inner-capsid.

The complete F gene of SF02 of goose paramyxovirus (GPV) has been cloned and analyzed. The sequence analysis demonstrated that the F gene of SF02 contains 1 662 nt and encodes 553 amino acids, and its cleavage activation site of F gene has the same deduced amino acid sequence, (112)R-R-Q-K-R-F(117), as the velogenic (highly pathogenic) strain of newcastle disease virus. The latter correlated with the virulence of the isolate in biological assays. The F gene of SF02 isolate with the domestic standard velogenic strain NDV, F48E9, shared 86.5% homology in nucleotide and 90.8% homology in amino acid sequences. The SF02 isolate is closer to some NDV strains prevalent in Taiwan and West-European countries in recent years. Based on the F gene sequence a multiplex RT-PCR method has been developed. It could be used for the discrimination of GPV from NDV.

In the present study we made out an animal model on rabbit whose trigeminus and facialis nerves were simultaneously or only the latter one was severed. The pathological changes in facial muscle atrophy under different nerve injuries were investigated. The degeneration of contractile proteins of upper lip muscle -- myosin and actin was observed. In addition, we also examined the ultrastructural changes in the muscle atrophy in the two above-mentioned nerve injury cases. We observed that the intact trigeminus nerve could delay and lighten the atrophy of facialis-denervated facial muscle and attenuate the degeneration of myosin and actin, as well as decrease the increment of collagen and maintain the ultrastructure of the thick and thin muscle filaments. These results may provide the possibility of improvement of clinical treatment for facial muscle palsy.

The cloning and sequence analysis of Chinese human cardiac myosin light chain 1 (CCMLC1) was previously reported. In this paper the cDNA of CCMLC1 was used as template and both of cDNAs of N and C terminal fragments of CCMLC1, each containing 98 amino acid residues, were obtained by PCR. Using the expressed products of both fragments, the binding experiments of two fragments to cardiacmyosin heavy chain of rat, human cardiac actin and to monoclonal antibody raised against CCMLC1, have been performed, respectively, by means of precipitation with GST-Sepharose beads. The results showed that all the heavy chain, actin and monoclonal antibody bound the N terminal fragment of CCMLC1 at different sites. Under experimental conditions, the binding of CCMLC1 with actin could affect the subsequent binding of CCMLC1 to heavy chain in topologically.

Since 1993 there has been outbreak of an acute lethal disease of the cultivated fleshy prawns (Penaeus chinesis, Osbeck) in China. After a short period of intensive studies we reported firstly the presence of a non-occluded baculovirus in the tissue of diseased prawns. The virus was also named as white spot syndrome baculovirus by some authors. Here, it is reported that, based on sequence analysis, an early and late transcription gene(1 197bp gene)of baculovirus was identified. Two hammerhead ribozymes RZ1 and RZ2 targeting the 54-56 bp and 314-316 bp of the 1 197 bp gene were designed, and in vitro cleavage experiments showed that under proper conditions the target gene could be completely cleaved by those ribozymes together or separately.

The nucleotide sequence of cDNA of ventricular myosin light chain 1 of Chinese patients was analyzed. Two remarkable differences in deduced amino acid sequence were found by comparison with amino acid sequence reported previously by Jackowski. The cDNA was expressed in E.coli and the expressed product was used for production of specific polyclonal and monoclonal antibodies. Using both of the poly- and monoclonal antibodies, as well as the expressed product, diagnosis kits for Acute Myocardial infarction was constructed (China patent application number 98 122066.5). Detailed studies on physiological function of cardiac myosin light chain 1 is under way in our lab.

A cDNA of rice ragged stunt oryzavirus(RRSV) coding for its protein PS9 was prepared and expressed in E.coli as a fusion protein then purified and cleaved by factor-Xa to a 38kD polypeptide. Using the IgG of the antiserum raised against the expressed fusion protein the gold immuno-labelling experiments provided a direct evidence that the 38kD polypeptide is one of the major proteins forming the virus spikes. Virus transmission experiments in brown planthopper fed with PS9 showed the inhibition of transmission of virus by the PS9 protein suggesting that the spike proteins of the virus may be essential for the virus infection.

According to a highly conserved 8 amino acid sequence of L proteins in Rhabdoviridae, a 24-mer degenerate oligonucleotide primer was designed to amplify the 5' terminus of the genomic RNA of wheat rosette stunt virus (WRSV), a plant rhabdovirus, by anchored PCR. The complete nucleotide sequence of the 5' trailer in WRSV genomic RNA was determined by deoxynucleotide sequencing of cloned cDNA derived from the anchored PCR products.

This short review article describes the recent progress in the research field of virus assembly. Two fundamental types of macromolecular interactions: the protein-protein and protein-nucleic acid are involved in the process of virus assembly. Virus assembly at least includes the following three major questions: 1. How the capsid subunits recognize and interact with each other? 2. What protein-protein and protein-nucleic acid interactions are involved in this process? 3. How is the specific selection of viral nucleic acid to be packaged into the virions? Virus assembly is an essential event in virus multiplication and maturation. Elucidation of virus assembly is not only important for better understanding of the viral maturation process, also will play the critical role in practical application, such as the development of vaccine against virus infection, the antiviral drug design and so on.

cDNA fragment located downstream of the WRSV NS protein gene was sequenced. Following an 80 nt untranslated region at the 5 'terminus, there is a 453 nt open reading frame(ORF) encoding a 17 kD protein, which was allowed to be expressed in E. coli using bacterial expression vector pGEX-3X and produced a 43 kD fusion protein. The result of Western blot showed that the fusion protein was able to react strongly with antibody raised against the purified WRSV particles. According to the similarities between the gene organizations of VSV and WRSV and between the molecular weights of deduced and expressed proteins, as well as the viral structural M protein, and to the result of Western blot, the 453 nt ORF was identified as WRSV M protein gene.

The cDNA fragment located downstream of the WRSV N protein gene was obtained from the cDNA library of WRSV by hybridization with a 24 nucleotides sequence fragment of the 3' end of mRNA of the N protein. The cDNA fragment was sequenced and on ORF encoding a 40 kD protein was found. The gene was expressed in E. coli DE3 and was identified by Western blot experiment as the NS gene of WRSV.