ABSTRACT
Cucumber mosaic virus was detected from infected Basella rubra L. with the indirect enzyme-linked immunosorbent assay. Total RNA was extracted from infected leaves and the cDNAs of coat protein gene of CMV-Ba were obtained by RT-PCR. The amplified cDNA fragments were then cloned into pMD 18-T vector and sequenced,the result showed that the CP gene was 657 nucleotides in length. This sequence was aligned with the obtained CP gene and some CMV strains or isolates of subgroup Ⅰ and subgroup Ⅱ in GenBank using DNA MAN software. The results showed that CMV-Ba shared 90.9%~93.8% and 76.1%~76.9% identity with the known CP genes of subgroup Ⅰ and Ⅱ respectively in nucleotide level,on the other hand,amino acids deduced from CMV-Ba CP gene shared 92.7%~97.7% and 72.4%~78.1% identity with the known CP protein of subgroup Ⅰ and Ⅱ,respectively. This suggested that CMV-Ba CP gene belongs to CMV subgroupⅠ.
ABSTRACT
<p><b>OBJECTIVE</b>To describe the epidemiology of neural tube defects (NTDs) in high- and low-prevalence areas of China.</p><p><b>METHODS</b>Birth defects surveillance data, collected from 1992 through 1994 was analyzed. These data were collected as part of the Sino-American cooperative project on NTDs prevention. We classified NTDs as anencephaly, encephalocele, high-level and low-level spina bifida (SB) according to location of the lesion (high vs low) and whether the defect was isolated or occurred in association with other birth defects. Rates were compared in the high-prevalence (North) region and the low-prevalence (South) region, after adjusted for classification, urban and rural, season and sex, and calculated the adjusted rate of NTDs.</p><p><b>RESULTS</b>Among seven hundred and eighty-four NTDs cases in 326 874 recorded births (include in livebirth, stillbirth and fetal death with a gestational age of at least 20 weeks), the overall NTDs prevalence in the North was 5.57/1,000 births, and in the South was 0.88/1 000. There were also significant differences in the prevalence of anencephaly, encephalocele, high-level and low-level SB between North (0.97, 0.49, 2.75 and 1.11/1,000 birth) and South (0.36, 0.15, 0.21 and 0.14/1,000 birth) (P < 0.01), with adjusted prevalences in the North 3 - 7 times higher than those in the South. There were significant difference between urban (2.04) and rural areas (6.57/1,000 birth) in the North (P < 0.01), urban (0.52) and rural areas (0.95/1,000 birth) in the South (P < 0.05). Adjusted prevalence rates in the rural were 3 - 4 times higher than those of urban in the North and 1.6 - 1.9 times higher than in the South; The seasonal rate of high-level SB increased between September and November in the North (3.44/1,000 birth), while the seasonal rate of anencephaly decreased between September and November (0.18/1,000 birth) in the South. However there were no seasonal changes in other classified NTDs both in the South and North.</p><p><b>CONCLUSIONS</b>The birth prevalence of NTDs in the North of China was the highest in the world. There were significant differences between the North and the South, urban and rural. There was seasonal change in high-level SB in the North, which was in accordance to the phenotype of NTDs. It was suggested that there might exist etiological heterogeneity among anecephalus, low- and high-level SB.</p>
Subject(s)
Female , Humans , Male , China , Epidemiology , Incidence , Neural Tube Defects , Epidemiology , SeasonsABSTRACT
The viral RNA was extracted from purified cymbidium mosa ic virus (CyMV) isolated from Dendrobium orchid cultivated in Hainan island. The gene of the movement protein (MP) was amplified by means of reverse transcripti on-polymerase chain reaction (RT-PCR), and cloned into pGEM-T easy vector. Se quence analysis showed that the gene fragment contained 3 open reading frames (O RFs) which may be encoding 14 kD、12 kD and 10 kD peptides. The nucleotide seque nce of the cloned gene fragment shared 97.8% homology with the MP genes of CyMV isolated from orchids cultivated in Hawaii and Singapore.
ABSTRACT
Banana bunchy top virus (BBTV) is the pathogen of banana bunchy top disease (BBTD); it seriously disserves the banana production. This paper reviewed the separation and purification methods, classifying and taxonomy status of BBTV; the genome structure and function of each encode protein of the virus; and the present problems that should be further clarified.