Biomedical subjects

Junping Wang

Publications and source records attributed to Junping Wang.

12 recordsLinked to original sources

PubMed2006

A high-density consensus map of barley linking DArT markers to SSR, RFLP and STS loci and agricultural traits.

BACKGROUND: Molecular marker technologies are undergoing a transition from largely serial assays measuring DNA fragment sizes to hybridization-based technologies with high multiplexing levels. Diversity Arrays Technology (DArT) is a hybridization-based technology that is increasingly being adopted by barley researchers. There is a need to integrate the information generated by DArT with previous data produced with gel-based marker technologies. The goal of this study was to build a high-density consensus linkage map from the combined datasets of ten populations, most of which were simultaneously typed with DArT and Simple Sequence Repeat (SSR), Restriction Enzyme Fragment Polymorphism (RFLP) and/or Sequence Tagged Site (STS) markers. RESULTS: The consensus map, built using a combination of JoinMap 3.0 software and several purpose-built perl scripts, comprised 2,935 loci (2,085 DArT, 850 other loci) and spanned 1,161 cM. It contained a total of 1,629 'bins' (unique loci), with an average inter-bin distance of 0.7 +/- 1.0 cM (median = 0.3 cM). More than 98% of the map could be covered with a single DArT assay. The arrangement of loci was very similar to, and almost as optimal as, the arrangement of loci in component maps built for individual populations. The locus order of a synthetic map derived from merging the component maps without considering the segregation data was only slightly inferior. The distribution of loci along chromosomes indicated centromeric suppression of recombination in all chromosomes except 5H. DArT markers appeared to have a moderate tendency toward hypomethylated, gene-rich regions in distal chromosome areas. On the average, 14 +/- 9 DArT loci were identified within 5 cM on either side of SSR, RFLP or STS loci previously identified as linked to agricultural traits. CONCLUSION: Our barley consensus map provides a framework for transferring genetic information between different marker systems and for deploying DArT markers in molecular breeding schemes. The study also highlights the need for improved software for building consensus maps from high-density segregation data of multiple populations.

Chromosome Mapping↗

PubMed2006

Isolation and RNA1 nucleotide sequence determination of a new insect nodavirus from Pieris rapae larvae in Wuhan city, China.

A new insect nodavirus is isolated from Pieris rapae larvae in Wuhan city, China and tentatively designated Wuhan nodavirus (WhNV). We here report the physicochemical characterization of WhNV and determine the nucleotide sequences of its larger segment of genome, RNA1. The results show that WhNV particles are isometric, non-enveloped, with a diameter of about 29nm. The virus has a major capsid protein and a minor capsid protein with estimated molecular mass of 40 and 44kDa, respectively. WhNV RNA1 is determined to be 3149nt long, containing a 1014-amino-acid open reading frame (ORF) encoding protein A with a calculated molecular mass of 114,608Da. The protein A shows 39 and 27% identity to its homologues in Pariacoto virus (PaV) and Striped jack necrosis nervous virus (SJNNV), respectively, but shows only 24% or less identity to its homologues in other insect Nodaviruses such as Nodamura virus (NoV), Black beetle virus (BBV), Boolarra virus (BoV) and Flock house virus (FHV). Predicted domains for six RNA-dependent RNA polymerase motifs and putative ORFs (protein B) are confirmed by sequence analysis of WhNV RNA1.

Amino Acid Sequence↗

PubMed2006

Sequence analysis of coat protein gene of Wuhan nodavirus isolated from insect.

Wuhan nodavirus (WhNV) particles are isometric, non-enveloped, and about 29 nm in diameter. In the previous study, we determine its physiochemical characterization and the nucleotide sequence of the larger genomic segment, RNA1 and identify it a nodavirus. WhNV RNA1 is 3,149 nt in length, encoding protein A, catalytic subunit of RNA-dependent RNA polymerase (RdRp). In this report, we complete the sequence determination of the smaller genomic segment, RNA2 of WhNV. WhNV RNA2 is determined to be 1,562 nt long, containing a 430-amino-acid open reading frame (ORF) encoding the coat protein of WhNV with a calculated molecular mass of 47,856 Da. The homology of the coat protein of WhNV and the homologous proteins of other nodaviruses either alphanodaviruses or betanodaviruses is very low. WhNV coat protein shares the highest identity (24%) with that of Lates calcarifer encephalitis virus (LCEV), a betanodavirus, and shares less than 16% identical amino acids with each of the alphanodaviruses. Furthermore, the prediction of WhNV capsid structure by 3D-PSSM shows that the capsid structure of WhNV resembles that of tomato bushy stunt virus (TBSV), a tombusvirus, which contains two domains, rather than the expected single-domain capsid protein of insect nodaviruses. The phylogenetic analysis indicates that WhNV is the most distantly related of both the alphanodaviruses and betanodaviruses, which provides significant new data for understanding the evolution of the nodavirus family.

Amino Acid Sequence↗

PubMed2006

Tube-immunoassay for rapid detection of carbaryl residues in agricultural products.

An antibody-based rapid, quantitative, and qualitative tube enzyme-linked immunosorbent assay (tube-ELISA) was developed and used to determine carbaryl (1-naphthyl methylcarbamate) residues in agricultural products (apple, Chinese cabbage, rice, and barley). The tube-ELISA is a competitive immunoassay in which the antibody is coated in the polystyrene tube, with a dynamic range between 0.7 and 46.3 microg kg(-1). Carbaryl was extracted from each agricultural sample by hand-shaking with methanol and examined for application to on-site analysis. After the liquid extraction, the sample extracts diluted with buffer were analyzed by rapid tube-ELISA directly. The overall test time was around 15-30 min, including sample preparation and assay performance. The results obtained from tube-ELISA correlated well with high-performance liquid chromatography (R2 > 0.9). The study shows that tube-ELISA is useful as a quality control tool and can be used to quantitatively detect carbaryl as well.

Carbaryl↗

PubMed2006

An improved recombineering approach by adding RecA to lambda Red recombination.

Recombineering is the use of homologous recombination in Escherichia coli for DNA engineering. Of several approaches, use of the lambda phage Red operon is emerging as the most reliable and flexible. The Red operon includes three components: Redalpha, a 5' to 3' exonuclease, Redbeta, an annealing protein, and Redgamma, an inhibitor of the major E. coli exonuclease and recombination complex, RecBCD. Most E. coli cloning hosts are recA deficient to eliminate recombination and therefore enhance the stability of cloned DNAs. However, loss of RecA also impairs general cellular integrity. Here we report that transient RecA co-expression enhances the total number of successful recombinations in bacterial artificial chromosomes (BACs), mostly because the E. coli host is more able to survive the stresses of DNA transformation procedures. We combined this practical improvement with the advantages of a temperature-sensitive version of the low copy pSC101 plasmid to develop a protocol that is convenient and more efficient than any recombineering procedure, for use of either double- or single-stranded DNA, published to date.

Animals↗

PubMed2005

Development of two enzyme-linked immunosorbent assays for detection of endosulfan residues in agricultural products.

Two competitive immunoassays, a laboratory assay based on microwell plates and a field test based on the use of polystyrene tubes, have been developed for the detection of endosulfan in agricultural products. The limit of detection for the microwell plate format was 0.8 +/- 0.1 microg/kg, and the limit of detection for the tube format was 1.6 +/- 0.2 microg/kg. A simple, rapid, and efficient extraction method was employed, and 76-112% recoveries of spiked samples were obtained. Methanol extracts of some agricultural product samples such as grape, carrot, spinach, and tobacco could be analyzed directly by immunoassay after dilution in 0.5% fish skin gelatin-phosphate buffered saline. In contrast, extracts of green tea caused significant interference in the assay, and a number of simple cleanup methods were ineffective in removing interference. However, use of the coagulating reagent polyvinyl pyrrolidone removed the matrix effect effectively. For the validation of the enzyme-linked immunosorbent assay (ELISA) tests, samples were analyzed by ELISA and gas chromatography (GC) after solid phase extraction. The relationship between data obtained using the tube assay and microwell assay was good (the lowest r(2) value was 0.94), and also, the immunoassay assay data correlated well with data obtained from GC analysis (the lowest r(2) value was 0.93). The developed immunoassay methods are the suitable methods for the rapid quantitative and reliable determination of endosulfan residues in agricultural products.

Camellia sinensis↗

PubMed2005

Enzyme immunoassay for the determination of carbaryl residues in agricultural products.

Carbaryl is one of the most important N-methyl carbamate insecticides used all over the world. To determine carbaryl residues in agricultural products (apple, pear, Chinese cabbage, rice and barley), a competitive enzyme-linked immunosorbent assay (ELISA) method was employed, and a simple and efficient extraction method for the rapid detection of carbaryl in agricultural products was developed with recoveries greater than 90%. After liquid extraction, sample extracts diluted with buffer were analysed by ELISA directly. Matrix effects can be avoided when a 1:20 dilution of apple, pear, rice and barley samples and a 1:50 dilution of Chinese cabbage samples with 0.5% fish skin gelation in phosphate-buffered saline containing 5% methanol. Sample extracts were analysed by ELISA and HPLC, and results obtained by two methods correlated well; the correlation was greater than 0.9.

Brassica↗

PubMed2005

Polymeric micelles for delivery of poorly soluble drugs: preparation and anticancer activity in vitro of paclitaxel incorporated into mixed micelles based on poly(ethylene glycol)-lipid conjugate and positively charged lipids.

Paclitaxel-loaded mixed polymeric micelles consisting of poly(ethylene glycol)-distearoyl phosphoethanolamine conjugates (PEG-PE), solid triglycerides (ST), and cationic Lipofectin lipids (LL) have been prepared. Micelles with the optimized composition (PEG-PE/ST/LL/paclitaxel = 12/12/2/1 by weight) had an average micelle size of about 100 nm, and zeta-potential of about -6 mV. Micelles were stable and did not release paclitaxel when stored at 4 degree C in the darkness (just 2.9% of paclitaxel have been lost after 4 months with the particle size remaining unchanged). The release of paclitaxel from such micelles at room temperature was also insignificant. However, at 37 degree C, approx. 16% of paclitaxel was released from PEG-PE/ST/LL/paclitaxel micelles in 72 h, probably, because of phase transition in the ST-containing micelle core. In vitro anticancer effects of PEG-PE/ST/LL/paclitaxel and control micelles were evaluated using human mammary adenocarcinoma (BT-20) and human ovarian carcinoma (A2780) cell lines. Paclitaxel in PEG-PE/ST/LL micelles demonstrated the maximum anti-cancer activity. Cellular uptake of fluorescently-labeled paclitaxel-containing micelles by BT-20 cells was investigated using a fluorescence microscopy. It seems that PEG-PE/ST/LL micelles, unlike micelles without the LL component, could escape from endosomes and enter the cytoplasm of BT-20 cancer cells thus increasing the anticancer efficiency of the micellar paclitaxel.

Antineoplastic Agents↗

PubMed2005

Isolation and identification of a new tetravirus from Dendrolimus punctatus larvae collected from Yunnan Province, China.

In this study, Dendrolimus punctatus tetravirus (DpTV) has been identified as a new member of the genus Omegatetravirus of the family Tetraviridae that may be related serologically to Nudaurelia capensis omega virus (NomegaV). DpTV particles are isometric, with a diameter of about 40 nm and a buoyant density of 1.281 g cm(-3) in CsCl. The virus has two capsid proteins (of 62 500 and 6800 Da) and two single-stranded RNA molecules (RNA1 and RNA2), which are 5492 and 2490 nt long, respectively. RNA1 has a large open reading frame (ORF) encoding a polypeptide of 180 kDa; RNA2 contains two partially overlapping ORFs encoding polypeptides of 17 and 70 kDa. The 180 kDa protein, which contains consensus motifs of a putative methyltransferase, helicase and RNA-dependent RNA polymerase, shows significant similarity to those of other tetraviruses. The 17 kDa protein is a PEST (Pro/Glu/Ser/Thr) protein of unknown function. The 70 kDa protein is the coat protein precursor and is predicted to be cleaved at an Asn-Phe site located after residue 570. The 70 kDa protein shows 86 and 66 % identity to its homologues in NomegaV and Helicoverpa armigera stunt virus, respectively. Secondary-structure analysis revealed that the RNAs of DpTV have tRNA-like structures at their 3' termini.

Animals↗

PubMed2005

Nucleotide sequence and genomic organization of a newly isolated densovirus infecting Dendrolimus punctatus.

The nucleotide sequence of a novel icosahedral DNA virus infecting Dendrolimus punctatus has been determined. The genome is 5039 nt long and includes inverted terminal repeats of 200 nt containing 131 nt long J-shaped terminal hairpins. The 'plus' strand of the genome contains three large open reading frames (ORFs), the left and the mid-ORFs (within the left ORF) in the left-half encoding the non-structural proteins and the right ORF in the right-half encoding viral capsid proteins. NS1 protein contains conserved replication initiation and DNA-dependent ATPase/helicase domains. VP1 protein contains a conserved PGY and phospholipase A2 motifs and shows high identities with VPs of Casphalia extranea densovirus and Bombyx mori densovirus-1 belonging to the genus Iteravirus. Phylogenetic analysis also revealed that this virus is most closely related to Casphalia extranea densovirus and Bombyx mori densovirus-1. Consequently, this virus was considered as a new third member of the genus Iteravirus of the subfamily Densovirinae, and designated Dendrolimus punctatus densovirus.

Animals↗

PubMed2004

Preparation and in vitro synergistic anticancer effect of vitamin K3 and 1,8-diazabicyclo[5,4,0]undec-7-ene in poly(ethylene glycol)-diacyllipid micelles.

Polymeric micelles consisting of poly(ethylene glycol)-distearoyl phosphoethanolamine conjugates (PEG-DSPE) loaded with Vitamin K3 (VK3) to 0.2 mg of drug/mg of carrier and with 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) to 0.06 mg of drug/mg of carrier were prepared. These micelles were stable for as long as 6 months during storage at 4 degrees C and did not change their size or release the incorporated drugs. Co-encapsulation of VK3 and DBU into PEG-DSPE micelles resulted in synergistic anticancer effects against both murine and human cancer cells in vitro. The synergism may be explained by the fact that the presence of DBU promotes the escape of drug-loaded micelles from the endosomes of cancer cells directly into the cytoplasm as demonstrated by fluorescent microscopy.

Animals↗

PubMed2002

Antitumor effects and pharmacokinetics of aclacinomycin A carried by injectable emulsions composed of vitamin E, cholesterol, and PEG-lipid.

The aim of this study was to prepare injectable emulsions of aclacinomycin A (E-ACM) and evaluate its acute toxicity, antitumor effects, and pharmacokinetics. In E-ACM, the surfactants were polyethylene glycol-lipid and cholesterol, and the oil phase was a vitamin E solution of ACM. The particle size distribution and the zeta potential of E-ACM were measured by the laser light dynamic scattering method. The ACM-loading efficiency was measured by using Sephadex G50 column chromatography. The acute toxicity, antitumor effects, and pharmacokinetics of E-ACM were studied in C57BL/6 mice bearing mouse murine histiocytoma M5076 tumors. The average diameter, zeta potential, and ACM-loading efficiency of E-ACM were 123.0 +/- 1.2 nm, - 12.67 +/- 1.35 mv, and 96.3 +/- 0.3% (n = 3), respectively. When stored at 7 degrees C in the dark for 1 year, the average diameter and ACM-loading efficiency of E-ACM changed into 126.3 +/- 2.3 nm and 97.4 +/- 0.8%, respectively, whereas 6.5 +/- 0.2% ACM decomposition was observed (n = 3). The plasma areas under the biodistribution curves (AUC)(0.03-48h) of E-ACM was significantly greater than that of free ACM (F-ACM). The heart, lung, and kidney AUC(0.03-48h) of E-ACM were significantly smaller than those of F-ACM whereas the liver and spleen AUC(0.03-48h) of E-ACM were not significantly different from those of F-ACM. The tumor AUC(0.03-48h) of E-ACM was significantly greater than that of F-ACM. E-ACM had lower acute toxicity and greater potential antitumor effects than F-ACM in M5076 tumor-bearing C57BL/6 mice. E-ACM is a useful tumor-targeting drug delivery system.

Aclarubicin↗