Search PubMed⌕ Search

Biomedical subjects

X P Zhou

Publications and source records attributed to X P Zhou.

At least 19 recordsLinked to original sources

Siegesbeckia yellow vein virus is a distinct begomovirus associated with a satellite DNA molecule.

Leaf samples of Siegesbeckia glabrescens showing yellow vein, enation, and stunting symptoms were collected in Guangdong province, China. A specific 500-bp product was consistently detected in total DNA extracts, amplified with universal primers specific for members of the genus Begomovirus. Comparison of partial DNA sequences revealed that these virus isolates were identical, and therefore isolates GD13, GD24 and GD27 were selected for further sequence analysis. The complete nucleotide sequences of GD13, GD24 and GD27 were all found to be 2768 nucleotides (nts) long, with two open reading frames (ORFs) in the virion-sense strand and four ORFs in the complementary-sense strand, typical of the Old World begomoviruses. Sequence identities among the three isolates ranged from 99.7 to 99.8%. When compared with other reported sequences of begomoviruses, GD13 was most closely related to papaya leaf curl China virus (AJ876548), with a sequence identity of 76.8%. In addition, all isolates were found to be associated with DNAbeta molecules. The complete DNAbeta sequences of isolates GD13, GD24 and GD27 were determined. Sequence analysis showed that they had highest sequence identity with DNAbeta of Eupatorium yellow vein virus (AJ438938) (44.0, 43.9 and 45.6% identity). GD13, GD24 and GD27 are considered to be isolates of a distinct begomovirus species for which the name Siegesbeckia yellow vein virus (SgYVV) is proposed.

Asteraceae↗

p53 gene (Gendicine) and embolisation overcame recurrent hepatocellular carcinoma.

Transcatheter arterial chemoembolisation (TACE) has become the standard treatment for unresectable hepatocellular carcinoma (HCC). However, this method is often unsuccessful. The p53 gene, which is present as a mutant form in many human tumours, is known to have broad spectrum antitumour effects when expressed normally. In this study, we report a 23 year old patient with recurrent HCC who was treated with the p53 gene (Gendicine) combining TACE, which resulted in a good clinical prognosis.

Adult↗

Molecular characterization of a new begomovirus infecting Senecio scandens in China.

Three begomovirus isolates, G46, G83 and G84 from Senecio scandens showing yellow mosaic symptoms were collected from Guangxi Province, P.R. China. The isolates were detected by PCR using universal primers for begomoviruses. Comparison of partial DNA-A sequences (approximately 500 bp) of the isolates revealed their 98.7-99.1% identity. The isolate G46, chosen for complete DNA-A sequencing, consisted of 2746 nt and had a typical genomic organization of begomoviruses. The G46 DNA-A had the highest sequence identity (72.4%) with that of Ageratum leaf curl virus among begomoviruses. The molecular data suggest that the isolate G46 is a new begomovirus (species), for which the name Senecio yellow mosaic virus (Senecio yellow mosaic virus) is proposed.

Asteraceae↗

Molecular characterization of tomato-infecting begomoviruses in Yunnan, China.

The importance of diseases of tomato caused by begomoviruses is increasing worldwide. Here, we report that several begomoviruses are associated with tomato leaf curl disease in Yunnan province, China. 14 tomato samples showing leaf curl symptoms were collected in three districts in Yunnan, and they fell into four groups according to their reaction with a panel of 16 monoclonal antibodies in TAS-ELISA. Comparison of partial DNA-A sequences amplified with degenerate primers confirmed the existence of several types of begomoviruses. The complete DNA-A sequences of 4 isolates (Y25, Y41, Y72, Y161), corresponding to the four groups, were determined. Sequence comparisons and phylogenetic analysis revealed that they corresponded to four previously identified begomoviruses. Groups I, II and IV are most closely related to Tomato yellow leaf curl China virus (TYLCCNV), Tobacco curly shoot virus (TbCSV) and Tobacco leaf curl Yunnan virus (TbLCYNV), respectively, while Group III shows close relationships with Tomato yellow leaf curl Thailand virus (TYLCTHV). In addition, all isolates in Groups I and III were found to be associated with DNAbeta molecules, while satellite DNA was not found in virus isolates in Groups II and IV. The complete DNAbeta sequences of three isolates from Group III (Y72, Y77, Y79) were determined. Sequence analysis showed that Y72beta, Y77beta and Y79beta seem to be different from other characterised DNAbeta, sharing the highest nucleotide sequence identity with DNAbeta of TbCSV.

Antigens, Viral↗

Molecular characterization of squash leaf curl Yunnan virus, a new begomovirus and evidence for recombination.

Virus isolate Y23V, obtained from squash showing leaf curl symptoms in Yunnan, China, was readily differentiated from four studied Chinese begomovirus isolates in reactions with a set of monoclonal antibodies raised against begomoviruses. The complete nucleotide sequence (2714 nts) of the DNA-A-like molecule of Y23V was determined. The DNA-A of Y23V is most closely related to that of tomato yellow leaf curl Thailand virus-[1] (TYLCTHV-[1]) (84% sequence identity). However, the AC1 and AC4 gene of Y23V DNA-A resembled to Pepper leaf curl virus from Bangladesh (PepLCBDV). The DNA-A of Y23V has three distinct regions: the region from 74-2071 nts is 95% identical to TYLCTHV-[1] excluding a 27 nt deletion; the following 386 nts are 91% identical to PepLCBDV and the rest of the DNA-A is not closely related to any reported begomovirus. Y23V, therefore, is considered to have arisen by recombination. The 84% sequence identity of Y23V with TYLCTHV-[1] allows Y23V to be considered as a distinct begomovirus species, for which the name squash leaf curl Yunnan virus (SLCYNV) is proposed.

China↗

In vivo accumulation of Broad bean wilt virus 2 VP37 protein and its ability to bind single-stranded nucleic acid.

The VP37 protein encoded by the RNA2 of Broad bean wilt virus 2 (BBWV2) was overexpressed in Escherichia coli. The protein was purified and a polyclonal antibody specific for the protein was produced. Time course studies by Western blot assays in BBWV2-infected Chenopodium quinoa leaves showed that the VP37 protein was present in cells of the inoculated leaves by 12 h post inoculation and in cells of systemically-infected leaves by 2 days post inoculation. The protein was able to accumulate to a high level in infected leaves at the late infection stage. Gel retardation and UV cross-linking assays demonstrated that the VP37 protein bound preferentially single-stranded (ss) RNA and DNA in a non-sequence-specific manner. The VP37 protein-RNA complex was stable in solutions containing less than 400 mM NaCl, but became fully dissociated in the solutions containing 800 mM NaCl. Sequence analysis of the VP37 protein and its ability to bind ssRNA and ssDNA suggest that the protein may play a role similar to the movement proteins reported for other plant viruses.

Blotting, Western↗

Maize dwarf mosaic disease in different regions of China is caused by Sugarcane mosaic virus.

Sugarcane mosaic virus (SCMV) was detected in all 62 maize samples collected from eight maize-growing provinces in China showing dwarf mosaic symptoms by immunocapture reverse-transcription polymerase chain reaction (RT-PCR). Maize dwarf mosaic virus (MDMV), Sorghum mosaic virus (SrMV) and Johnsongrass mosaic virus (JGMV), however, were not detected in any of the samples by RT-PCR. Eleven cDNA fragments of approximately 0.8 kilobases covering most of the coat protein (CP) gene of SCMV were sequenced and sequence analysis indicates that these eleven isolates share 98.1 to 100 % identity at the amino acid level. Sequence comparison and phylogenetic analysis of the CP genes from the eleven Chinese isolates as well as 21 SCMV subgroup virus isolates indicate that the eleven Chinese virus isolates were closely related to SCMV with 97.0 to 98.1 % sequence identity at the amino acid level, while relatively lower sequence identity was found with MDWV, SrMV or JGMV. The results indicate that the Chinese isolates are members of the SCMV species, and thus, SCMV can be considered as the most common and important potyvirus infecting maize in China.

Amino Acid Sequence↗