Nucleus pulposus cells degeneration model: a necessary way to study intervertebral disc degeneration.

The availability of an appropriate and reliable research model is helpful for researchers to understand the occurrence and development of diseases. Historically, animal models have been beneficial in the study of intervertebral disc degenerative diseases, but intervertebral disc degeneration (IDD) is a precise and complex process that needs to appear and occur in a specific tissue microenvironment, and animal degeneration models cannot fully simulate these parameters. These challenges must be overcome, especially when animal models cannot fully generalise the complex pathology of humans. In the past few years, the research on the cell disease model has made important progress, and the construction of the nucleus pulposus cell (NPC) degeneration model has become an indispensable step in studying the occurrence and development of IDD. Here, several different methods of constructing NPC degeneration models and indicators for testing the effect of modelling are introduced. The practical applications of cell models constructed by different methods are enumerated to screen and evaluate effective methods of establishing degenerative cell models and explore the mechanism of IDD.

[Mixed reality technology in fibula flap preparation clinical teaching application].

Objective: To explore the effect of the application of mixed reality (MR) technology in clinical teaching of fibular flap preparation. Methods: Twenty residents from the Department of Oral and Maxillofacial Surgery in School of Stomatology, the Fourth Military Medical University in 2018 and 2019 participated in the present study. They were randomly divided into two groups according to the method of random drawing. The teaching content of the two groups was fibular flap preparation. The MR group was taught by using the new teaching mode which was mainly based on MR, while the conventional teaching group was educated by conventional teaching method. At the end of the training, the theoretical knowledge and operational skills of the residents were statistically analyzed to evaluate the learning effect. Questionnaire survey was also conducted. Each item in the questionnaire was scored between 0 and 5, representing poor to excellent. Results: The theoretical scores of MR group (91.4±4.4) were higher than that of the conventional teaching group (83.3±3.2) (P<0.01). The durations of preoperative marking and simulated osteotomy in MR group [(5.7±1.2) and (20.9±2.28) min, respectively] were shorter than those in the conventional teaching group [(7.2±1.7) and (26.1±3.6) min, respectively] (P<0.05). The results of the questionnaire showed that MR group had a significant improvement in the scores of classroom atmosphere, satisfaction, three-dimensional construction, theoretical knowledge and problem-solving ability (P<0.01). However, there was no statistically significant difference in scores of learning concentration between the two groups (P>0.05). Conclusions: The application of MR technology achieved a better teaching effect, which could help residents to deeply understand the methods of fibular flap preparation, and showed a broad application prospect.

Integrated transcriptomics and metabolites at different growth stages reveals the regulation mechanism of bolting and flowering of Angelica sinensis.

The root of Angelica sinensis is one of the most widely used traditional Chinese medicines. In commercial planting, early bolting and flowering (EBF) of ca. 40% of 2-year-old plants reduces root yield and quality. Although changes in physiology in bolted plants have been investigated, the mechanism activating EBF has not been identified. Here, transcriptomics profiles at four different growth stages (S1 to S4) were performed, gene expression was validated by qRT-PCR and the accumulation of endogenous hormones quantified by HPLC. A total of 60,282 unigenes were generated, with 2,282, 1,359 and 2,246 differentially expressed genes (DEGs) observed at S2 versus S1, S3 versus S2 and S4 versus S3, respectively; 558 genes that co-exist in at least three stages from S1 to S4 were obtained. Functional annotation classified 38 DEGs linked to flowering pathways: photoperiodism, hormone signalling, carbohydrate metabolism and floral development. The levels of gene expression, hormones (GA1 , GA4 and IAA) and soluble sugars were consistent with the EBF. It can be concluded that the EBF of A. sinensis is controlled by multiple genes. This integrated analysis of transcriptomics, together with targeted hormones and soluble sugars, provides new insights into the regulation of EBF of A. sinensis.

Effect of UV-B radiation on growth, flavonoid and podophyllotoxin accumulation, and related gene expression in Sinopodophyllum hexandrum.

Sinopodophyllum hexandrum is an alpine medicinal plant that produces the anticancer compound podophyllotoxin (PPT). Although a positive relationship between PPT content and altitude has been proved and low temperature enhances plant growth and PPT accumulation has also been revealed, the role of UV radiation in regulating growth and PPT accumulation is still unclear In this study, morphophysiological traits, metabolites content and related genes expression were investigated by exposing S. hexandrum seedlings to treatment with UV-B radiation. The results showed that the contents of soluble sugars and flavonoids, and the expression levels of genes involved in glycometabolism (XET and ß-1,3-glucanase) and flavonoid biosynthesis (PAL,C4H,4CL,CHS1 and DTX41) were enhanced in response to UV-B compared to CK. Moreover, genes involved in stress tolerance (MYB, WRKY,APX3 and EX2) were also upregulated in response to UV-B radiation. Although the whole plant biomass exhibited slightly increased values that depended largely on root development, the contents of chlorophyll and PPT and the expression levels of genes involved in photosynthesis (matK, ndhF,rbcL and ycf5) and PPT biosynthesis (C3H,CCoAMT,CCR,CAD, DPO, PLR,SDH, CPY719A23,OMT3,CYP71CU1,OMT1and 2-ODD) were significantly decreased in response to UV-B compared to CK. It can be concluded that UV-B radiation promotes soluble sugars and flavonoids accumulation, but inhibits PPT biosynthesis in S. hexandrum.

Targeting EZH2 by microRNA-449a inhibits osteosarcoma cell proliferation, invasion and migration via regulation of PI3K/AKT signaling pathway and epithelial-mesenchymal transition.

OBJECTIVE: Osteosarcoma (OS) is one common bone malignant tumor prevailing in young adults and children. It is increasingly recognized microRNA 449a (miR 449a) as an anti-tumor factor in various tumours. However, little is known about the biological significance of miR 449a in OS. The intent of our study was to seek the prognostic values of miR-449a in OS. PATIENTS AND METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to examine the level of miR-449a expression in 48 pairs of OS tissues and para-cancerous specimens, and the relationship between miR-449a level and clinical features of OS patient prognosis was analyzed. Moreover, we measured the miR-449a expression levels in OS cells. Transwell assay was further performed to investigate whether miR-449a influenced MG63 cell migration and invasion, which was important for malignant metastases. RESULTS: Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrated a notable decrease of miR-449a expressions in OS. The declined miR-449a expression was relevant with the poor prognosis and malignant clinicopathologic characteristics of OS patients. Thereafter, the functional assay was performed to determine the role of miR-449a in OS progression. Results of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assays and transwell assays indicated that miR-449a overexpression significantly repressed OS cell proliferation, invasion, and migration. Furthermore, luciferase reporter assay showed that enhancer of zeste homolog 2 (EZH2) was a downstream target of miR-449a in OS cells. Additionally, Western blot analysis demonstrated that miR-449a exerted anti-OS functions via the regulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway and epithelial-mesenchymal transition. We also indicated that miR-449a restoration could inhibit in vivo tumor growth. CONCLUSIONS: These results manifested that miR-449a may thus be used as a therapeutic target in OS treatments.

The role of cathepsin K in oral and maxillofacial disorders.

Cathepsin K (CTSK) was thought to be a collagenase, specifically expressed by osteoclasts, and played an important role in bone resorption. However, more and more research found that CTSK was expressed in more extensive cells, tissues, and organs. It may not only participate in regulating human physiological activity, but also be closely related to a variety of disease. In this review, we highlight the relationship between CTSK and oral and maxillofacial disorders on the following three aspects: oral and maxillofacial abnormities in patients with pycnodysostosis caused by CTSK mutations, oral and maxillofacial abnormities in Ctsk(-/-) mice, and the role of CTSK in oral and maxillofacial diseases, including periodontitis, peri-implantitis, tooth movement, oral and maxillofacial tumor, root resorption, and periapical disease.

Sequence and phylogenetic analyses of the M and N genes of porcine epidemic diarrhea virus (PEDV) strains in Anhui Province, China.

To assess the homology and phylogenetic relationship between porcine epidemic diarrhea virus (PEDV) Anhui strains and other PEDV strains, molecular homology and phylogenetic analyses of Anhui PEDV field strains were compared with those of reference strains. The results revealed that the M and N genes of PEDV were 681 and 1326 bp long, respectively. The nucleotide sequences of the N genes of Anhui PEDV strains were 95.9-99.9% homologous with each other, and the deduced amino acid sequences were 92.5-99.8% homologous. Compared with the PEDV reference strains, the Anhui PEDV field strains had 94.1-99.5% nucleotide sequence homology in the N gene and 91.2-97.5% amino acid mutation homology in the N protein. The nucleotide sequences of the M genes of Anhui PEDV were 98.3-100% homologous, and the deduced amino acid sequences were 96.5-99.6% homologous. Compared with the PEDV reference strains, the Anhui PEDV field strains had 96.9-100% nucleotide sequence homology in the M gene and 96.5-99.6% amino acid homology in the M protein. The Anhui strains were genetically similar to USA strains (USA/Iowa/16465/2013 and USA/Indiana/17846/2013) but different from European (CV777;Br1/7), Korean (Chinju99), and Japanese (83p-5) strains.

Comparative transcriptome analysis of Nile tilapia (Oreochromis niloticus) in response to alkalinity stress.

To identify genes of potential importance to alkalinity tolerance, RNA sequencing (RNA-Seq) was performed to survey gill transcriptome profiles from freshwater (FW) and alkaline water (AW) exposed Nile tilapia (Oreochromis niloticus). A total of 22,724,036 (AW)/16,461,040 (FW) single-end reads were generated in which 20,304,348 (AW)/14,681,290 (FW) reads (90.0/89.72%) were aligned to the reference genome. Differential expression analysis revealed 302 up-regulated and 193 down-regulated genes between AW- and FW-exposed fish. These differentially expressed genes were enriched in several Gene Ontology (GO) terms related to "stress response", "heme binding", and "carbonate dehydratase activity". Meanwhile, significant KEGG pathways were enriched in energy metabolism, including nitrogen and sulfur metabolism. These results demonstrate the response of Nile tilapia exposed to alkaline-water and might provide valuable information to further understand the molecular mechanisms of adaptation of fish to alkaline environments.

Delivery of AIB1 siRNA by Ca2+/PEI/heparin composite nanoparticles effectively inhibits the growth of human breast cancer.

Here, a novel carrier fabricated by the interaction of negatively charged heparin and positively charged PEI and Ca2+ was investigated to deliver AIB1 siRNA into breast cancer cells both in vitro and in vivo. Ca2+/PEI/heparin nanoparticles were prepared by simply mixing heparin, PEI and CaCl2 aqueous solution. Heparin in the Ca2+/PEI/heparin nanoparticles (40.9% heparin, w/w) decreased the cytotoxicity of PEI. According to the MTT assay, Ca2+/PEI/heparin NPs are superior to commercial Lipofectamine 2000 considering the safety. The Ca2+/PEI/heparin NPs are able to deliver siAIB1 into breast cancer cells as effectively as Lipofectamine 2000 both in vitro and in vivo. The in vivo experiment also indicated that the NF-κB/BCL-2 signal pathway might be the downstream signal pathway of AIB1 in regulating breast cancer proliferation and progression.

EIF5A2 predicts outcome in localised invasive bladder cancer and promotes bladder cancer cell aggressiveness in vitro and in vivo.

BACKGROUND: EIF5A2, eukaryotic translation initiation factor 5A2, is associated with several human cancers. In this study, we investigated the role of EIF5A2 in the metastatic potential of localised invasive bladder cancer (BC) and its underlying molecular mechanisms were explored. METHODS: The expression pattern of EIF5A2 in localised invasive BC was determined by immunohistochemistry. In addition, the function of EIF5A2 in BC and its underlying mechanisms were elucidated with a series of in vitro and in vivo assays. RESULTS: Overexpression of EIF5A2 was an independent predictor for poor metastasis-free survival of localised invasive BC patients treated with radical cystectomy. Knockdown of EIF5A2 inhibited BC cell migratory and invasive capacities in vitro and metastatic potential in vivo and reversed epithelial-mesenchymal transition (EMT), whereas overexpression of EIF5A2 promoted BC cells motility and invasiveness in vitro and metastatic potential in vivo and induced EMT. In addition, we found that EIF5A2 might activate TGF-ß1 expression to induce EMT and drive aggressiveness in BC cells. EIF5A2 stabilized STAT3 and stimulated nuclear localisation of STAT3, which resulted in increasing enrichment of STAT3 onto TGF-ß1 promoter to enhance the transcription of TGF-ß1. CONCLUSIONS: EIF5A2 overexpression predicts tumour metastatic potential in patients with localised invasive BC treated with radical cystectomy. Furthermore, EIF5A2 elevated TGF-ß1 expression through STAT3 to induce EMT and promotes aggressiveness in BC.

First Report of Bacterial Soft Rot of Konnyaku Caused by Dickeya dadantii in China.

Konnyaku (Amorphophallus rivieri Durieu) is grown in some rural areas of China as an important cash crop. In 2011, there was a serious outbreak of Konnyaku soft rot in Xuanwei District of Yunnan Province of China. The disease was characterized by partial or complete tuber rot. At its anaphase, the soft rot may move up the stem, causing the caudex to decay and the whole plant to collapse. If the stem is strong or big enough, the soft rot may develop on one side of the stem, leaving the other side healthy for several days. In this case, the stem does not collapse, and etiolation may be observed on the rotten tissue. In serious cases, up to 80% of the plants were infected. The disease is even more serious if Konnyaku is grown continuously in the same field for more than one year. At its worst, the disease can wipe out the whole crop. In 2012 and 2013, we isolated 46 strains of bacteria from 60 Konnyaku tuber samples with soft rot symptoms from Xuanwei District. All strains grew on CVP medium, and produced iridescent, cross-hatched translucent colonies in deep, cuplike depressions or pits. All strains were facultatively anaerobic, gram-negative, straight rod-shaped cells with peritrichous flagella. All strains were catalase-positive, but oxidase-negative. They were able to ferment glucose, reduce nitrate, produce ß-galactosidase and H2S, and they utilized L-arabinose, D-galactose, D-glucose, glycerol, D-mannose, D-ribose, and sucrose, but did not produce urease, or acid from adonitol. Pectobacterium carotovorum subsp. carotovorum (syn. Erwina carotovora subsp. carotovora) has been commonly accepted as the causal agent of Konnyaku soft rot in Japan and China (1,3). Our studies also confirmed that P. carotovorum subsp. carotovorum caused Konnyaku soft rot, but the colony morphology and physiological and biochemical characteristics of these bacteria differed greatly from those of P. carotovorum subsp. carotovorum and other pectolytic Pectobacterium species. They grew at 37°C, caused potato soft rot, produced acid from melibiose, citrate, raffinose, and lactose, but did not produce acid from sorbitol and arabitol. The strain also utilized malonate but not keto-methyl glucoside as the sole carbon source. All strains were positive for phosphatase. Forty-one of 46 strains were sensitive to erythromycin. Thirty-seven of 46 strains produced indole. All tests were conducted with P. carotovorum subsp. carotovorum standard strain C2 isolated from Chinese cabbage as a positive control. Healthy Konnyaku tubers were inoculated with suspensions of the strains with a concentration of 108 CFU/ml in sterile water to confirm pathogenicity. After ~48 h, tuber rot symptoms were observed on all inoculated Konnyaku tubers. In comparison, there were no symptoms on tubers inoculated with sterile water. The bacterium was re-isolated from the infected Konnyaku tubers and identified as Dickeya dadantii, in accordance with Koch's postulates. All strains were confirmed by using the species-specific primers ERWFOR/CHRREV (2), which amplified a 450-bp DNA fragment by PCR assay. To our knowledge, this is the first report of Konnyaku soft rot caused by D. dadantii in China. References: (1) N. Hayashi. Gunma J. Agric. Res. A (Genera1) 5:25, 1988. (2) E. J. Smid et al. Plant Pathol. 44:1058, 1995. (3) J. Y. Tang et al. J. Yunnan Agric. Univ. 16:185, 2001.

AIB1 predicts bladder cancer outcome and promotes bladder cancer cell proliferation through AKT and E2F1.

BACKGROUND: We previously demonstrated that AIB1 overexpression is an independent molecular marker for shortened survival of bladder cancer (BC) patients. In this study, we characterised the role and molecular mechanisms of AIB1 in BC tumorigenicity. METHODS: AIB1 expression was measured by immunohistochemistry in non-muscle-invasive BC tissue and adjacent normal bladder tissue. In addition, the tumorigenicity of AIB1 was assessed with in vitro and in vivo functional assays. RESULTS: Overexpression of AIB1 was observed in tissues from 46 out of 146 patients with non-muscle-invasive BC and was an independent predictor for poor progression-free survival. Lentivirus-mediated AIB1 knockdown inhibited cell proliferation both in vitro and in vivo, whereas AIB1 overexpression promoted cell proliferation in vitro. The growth-inhibitory effect induced by AIB1 knockdown was mediated by G1 arrest, which was caused by reduced expression of key cell-cycle regulatory proteins through the AKT pathway and E2F1. CONCLUSION: Our results suggest that AIB1 promotes BC cell proliferation through the AKT pathway and E2F1. Furthermore, AIB1 overexpression predicts tumour progression in patients with non-muscle-invasive BC.

First Report of Corynespora Leaf Spot on Patchouli Caused by Corynespora cassiicola in China.

Patchouli (Pogostemon cablin (Blanco) Benth.) is mainly cultivated in Southeast Asia as a medicinal shrub and a source of patchouli oil used in perfumery. In 2008, a leaf spot disease was observed on patchouli plants grown on most farms (some farms had 99% incidence) in Wanning, the predominant cultivation location in the Hainan Province of China. The disease usually began at the tip of leaves, the main veins, or small veinlets. Severely irregular-shaped dark brown leaf spots expanded over 5 to 10 days, eventually causing infected leaves to abscise. The time from initial leaf lesions to abscission usually took 1 month. The disease was usually most severe in April and May, causing significant economic losses along with quality losses to patchouli oil extracted from leaves. To isolate the causal pathogen, diseased leaves were collected in August 2008 from a farm of the Hainan Branch Institute of Medicinal Plant Development in Wanning, surface sterilized in 75% ethanol for 1 min, transferred to potato dextrose agar (PDA), and incubated at 28°C for 14 days. Single-spore cultures of three isolates were obtained and identified as Corynespora cassiicola (Berk. & Curt.) Wei. on the basis of morphological and physiological features (1). Genomic DNA was extracted from all the cultures. The internal transcribed spacer (ITS) region of the rDNA was amplified using primers ITS1 (5'-TCCGATGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3'). Amplicons were 546 bp (GenBank Accession No. HM145960) and had 99% nucleotide identity with the corresponding sequence (GenBank Accession No. GU138988) of C. cassiicola isolated from cassava (Manihot esculenta Crantz). To satisfy Koch's postulates, 50-day-old potted plants in a tent were sprayed until runoff with a spore suspension (1 × 106 spores/ml) prepared from 10-day-old cultures. Using this spray method, one isolate was inoculated separately onto nine leaves of three potted plants. The potted plants were covered with plastic bags to maintain high humidity for 48 h and then placed outside under natural environmental conditions (temperature 20 to 28°C). Another nine leaves of three potted plants, sprayed only with sterile water, served as noninoculated control plants. Leaf spot symptoms similar to those on diseased field plants appeared after 7 days on all inoculated plants. C. cassiicola was reisolated from all inoculated test plants. No symptoms were observed on the control plants. To our knowledge, this is the first report of C. cassiicola causing a leaf spot disease on patchouli in China. Other previous reports of this disease were from Cuba (2). This pathogen has also been reported previously to be economically important on a number of other hosts. On patchouli plants, more attention should be given to prevention and control measures to help manage this disease. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute: Kew, Surrey, England, 1971. (2) I. Sandoval et al. Cienc. Tec. Agric., Prot. Plant. 10:21, 1987.

First Report of Alternaria Leaf Blight on Bupleurum chinense Caused by Alternaria alternata in China.

Bupleurum chinense DC. (family Umbelliferae) is an important medicinal herb in traditional Chinese medicine and is cultivated as an economically important plant in China (2). From 2006 to 2009, severe foliar disease was observed on B. chinense in Haidian, Changping, and Shunyi districts, Beijing, China. Approximately 75 to 85% of fields were affected with disease incidence ranging from 65 to 90%. Distribution of the disease in affected B. chinense fields was generally associated with high soil moisture, often corresponding to poor drainage. Initial symptoms first appeared on older leaves as irregularly shaped, minute, dark brown-to-black spots, with yellow borders on the edge of the affected leaflet blade. As the disease progressed, the lesions expanded, causing the leaflets to turn brown, shrivel, and die. Isolations performed on potato dextrose agar (PDA) initially resulted in white colonies. After 7 days of incubation at 25°C, the colonies turned gray or brown. Conidia varied in size from 10 × 6 to 40 × 12 µm, appeared brown to dark brown or olive-brown, were short beaked and borne in long chains, oval and bean-shaped with one to six transverse septa and zero to three longitudinal septa. Sequences of the rDNA from the internal transcribed spacer regions 1 and 2 and the 5.8S gene were amplified using primers ITS1 and ITS4, were obtained from three isolates, and comparisons with GenBank showed 100% similarity with A. alternata (Genbank Accession No. AB470912.1). For pathogenicity tests, three isolates were grown on PDA for 14 days. Inoculations were performed on detached, surface-sterilized, and healthy B. chinense leaflets following the method of Belisario (1). A 5-µl drop of conidial suspension containing 1 × 105 CFU/ml was placed on each leaflet and 12 leaves per isolate were used. Leaves were incubated in a growth chamber (80 to 90% relative humidity; 50 to 60 klx/m2 light intensity with a 12-h photoperiod). After 5 days, leaf spots similar to the original symptoms developed on all inoculated leaves and A. alternata was consistently reisolated from symptomatic leaf tissues on PDA. Control leaflets inoculated with sterile water remained asymptomatic. The experiment was performed three times. To our knowledge, this is the first report of A. alternata on B. chinense from China. References: (1) A. Belisario et al. Plant Dis. 83:696, 1999. (2) C. Sui et al. Plant Dis. 93:844, 2009.

Spin-dependent current modulation in organic spintronics.

We investigate the spin-dependent current modulation in a model organic semiconductor sandwiched by two ferromagnetic electrodes. When the conductance band of the system is activated by an applied bias voltage, the majority-spin electrons are successively blocked within the organic semiconductor and form nonequilibrium polarons. This majority-spin blockage will modulate the minority-spin current due to the effective spin-spin coupling mediated by the electron-phonon interaction. This study suggests that the spin-blockage induced current modulation is a rather robust phenomenon in organic spintronics.

First Report of Broad bean wilt virus 2 Infecting Bupleurum chinense in China.

Samples of the medicinal plant, Bupleurum chinense DC., were collected in October 2007 from the garden of the Institute of Medicinal Plant Development in Beijing. Partial fragments of the genomic RNA1 and RNA2 of Broad bean wilt virus 2 (BBWV-2) were obtained from the root cDNA library of these plants. Sequence analyses showed the 1,896-nt RNA1 fragment (GenBank No. FJ485684) encoding a portion of the RNA-dependent RNA polymerase (RdRp) and the 2,017-nt RNA2 fragment (No. FJ485685) encoding 612 amino acids of the complete large (LCP) and small coat protein (SCP), respectively. The amino acid identities of LCP and SCP were 90.8 to 96.7% compared with sequences of other BBWV-2 isolates deposited in the GenBank with the highest homology to Japanese IP (No. AB018698) and the lowest to Japanese 1-2 (No. AB018701). This strongly suggests that the B. chinense plants utilized for cDNA library construction were infected by what appears to be an isolate of BBWV-2. Seeds from the same batch were sown again in the same garden in May 2008. In August 2008, approximately 30% of these plants showed mosaic, distortion, and stunting. Reverse transcription (RT)-PCR amplicons were obtained from eight symptomatic plants using a pair of conserved primers for specific detection of viruses within the Fabavirus genus (2). A symptomless plant tested negative by RT-PCR. The same single 391-bp amplicon of RNA1 (No. FJ485686) obtained from five of those eight symptomatic plants were cloned and sequenced. Sequence comparison with the corresponding sequences of other BBWV-2 isolates showed that the sequenced isolate was most closely related to B935-a Chinese faba bean isolate (No. AF149425). Crude sap of one diseased B. chinense plant was used for mechanical inoculation to Chenopodium amaranticolor Coste & Reyn. Chlorotic local lesions were observed on inoculated leaves 5 days after inoculation, and subsequently, systemic mottle and malformed symptoms appeared on the upper leaves. Twelve plants were inoculated and all plants showed symptoms of virus infection. RT-PCR tests of inoculated indicator plants showing local lesions confirmed the presence of BBWV-2. To date, Clover yellow vein virus and Lettuce mosaic virus have been isolated from the genus Bupleurum (B. griffithii hort. and B. falcatum L. sensu lato) in Japan and Israel, respectively (1,3). Furthermore, to our knowledge, no genomic sequence of BBWV-2 naturally infecting plants in the family Umbelliferae/Apiaceae has been reported. Therefore, this is the first report of BBWV-2 on B. chinense (Umbelliferae/Apiaceae), which was designated as a BC isolate of BBWV-2. In China, BBWV-2 was reported to be infecting and causing heavy losses to many plant species mostly belonging to the family Leguminosae (4). B. chinense is a commonly used bulk medicinal plant mainly cultivated in Hebei, Sichuan, Gansu, and Shanxi provinces in China for decoction pieces and extracts of its dried roots, which are also exported to Japan, Korea, and Southeast Asia. These results demonstrate the need for further assessment of BBWV-2 incidence and the losses it may cause. References: (1) J. Cohen et al. Phytoparasitica 30:88, 2002. (2) R. M. Ferrer et al. J. Virol. Methods 144:156, 2007. (3) H. Yamamoto. Jpn. J. Phytopathol. 69:420, 2003. (4) X. P. Zhou et al. Acta Phytopathol. Sin. 26:347, 1996.

Pathways of polaron and bipolaron transport in DNA double strands.

We investigate the pathways of polaron and bipolaron transports in DNA double strands with an extended Su-Schrieffer-Heeger model involving the effects of solvent polarization. We find that the long-range transport of polaron/bipolaron under high electric field at low temperature is the field-facilitated sequential tunneling through spatial-disordered potential barriers via multiple intrastrand and interstrand pathways. Although the interstrand pathways may be very active and effective in some DNA sequences, the intrastrand ones always dominate the charge transfer when the excess charge moves close to the final acceptor.