Publications by authors named "De-fang Dai"
Background: Heterologous booster immunisation with orally administered aerosolised Ad5-nCoV vaccine (AAd5) has been shown to be safe and highly immunogenic in adults. Here, we aimed to assess the safety and immunogenicity of heterologous booster immunisation with orally administered AAd5 in children and adolescents aged 6-17 years who had received two doses of inactivated vaccine (BBIBP-CorV or CoronaVac).
Methods: We did a randomised, open-label, parallel-controlled, non-inferiority study to assess the safety and immunogenicity of heterologous booster immunisation with AAd5 (0·1 mL) or intramuscular Ad5-nCoV vaccine (IMAd5; 0·3 mL) and homologous booster immunisation with inactivated vaccine (BBIBP-CorV or CoronaVac; 0·5 mL) in children (aged 6-12 years) and adolescents (aged 13-17 years) who had received two doses of inactivated vaccine at least 3 months earlier in Hunan, China.
[Molecular epidemiology investigation of rabies virus nucleoprotein genes in China].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
April 2010
Objective: To study the relationship between the distribution of rabies virus and genetic variation, the genetic characterization and variation of rabies virus strains in China were analyzed.
Methods: The downstream 720 nucleotides of Nucleoprotein (N) gene coding region of the rabies specimens from different areas and host animals were sequenced, and then homology and phylogenesis were analyzed.
Results: Nucleotide similarities of 34 N gene sequences were 87.
[Viral surveillance on rabies in Hunan province, in 2006].
Zhonghua Liu Xing Bing Xue Za Zhi
October 2008
Objective: To understand the source and distribution of rabies virus (RV) in Hunan province with viral surveillance in order to provide scientific measures for prevention and control on rabies.
Methods: Brain samples from healthy-looking domestic dogs were collected in the agricultural markets at the districts of high, middle, and low incidence rates and detected by direct Immunofluorescence assay (DFA). Positive samples would be further detected by RT-PCR and the surveillance samples were detected by RT-PCR.
[Characterization of rabies virus phosphoprotein in high prevalence provinces of China].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
June 2008
Article Synopsis
- The study focused on analyzing genetic variations of the rabies virus phosphoprotein in China, particularly in high-incidence areas like Guangxi, Guizhou, and Hunan.
- The nucleotide and amino acid sequences of the P gene were sequenced, showing a high similarity ranging from 82.1% to 100% for nucleotides and 87.5% to 100% for amino acids, indicating that minor variations don't significantly affect the protein’s biological functions.
- All examined rabies viruses are classified under genotype 1, suggesting they have a shared evolutionary history, with some isolates from Hunan possibly related to those found in Thailand.
[Survey and anslysis of infection rate of dog rabies in the regions with high incidence of human rabies].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
June 2008
Objective: To investigate the situation of dog rabies and analyze it's relationship with human rabies.
Methods: In Guizhou, Guangxi and Hunan provinces which suffered from rabies most heavily, one or two cities were selected respectively from regions with high-, middle-, low-incidence rate of human rabies as investigation spots where Dogs' brain specimens were collected and detected with both direct immunofluorescence assay (IFA) and RT-PCR.
Results: A total of 2887 specimens were collected and 66 of these were positive for IFA and RT-PCR.
[Virological surveillance on hemorrhagic fever with renal syndrome in Hunan province in 2006].
Zhonghua Liu Xing Bing Xue Za Zhi
December 2007
Objective: To understand the rate of viral carrying status among rodents as well as genotypes and distribution of Hantaviruses (HV) isolated in Hunan province.
Methods: With DFA, the HV antigen in lung tissues of rodents was detected. The total viral RNA was extracted from the lung tissues of the HV infected rats and amplified with reverse transcrition-polymerase chain reaction (RT-PCR), using the HV genotype specific primers.
Article Synopsis
- A study isolated 57 rubella virus strains from throat swabs of patients during outbreaks in 10 provinces of China between 2003 and 2007, focusing on their genetic characteristics.
- Phylogenetic analysis revealed that 55 of these strains belonged to the 1E genotype, while 2 strains were of the 2B genotype, indicating that 1E was the dominant strain during this time period.
- Most mutations identified were silent, showing high conservation in amino acid sequences, with a single notable amino acid change in a couple of strains, highlighting differences from earlier rubella viruses circulating from 1979 to 2002.
[Surveillance of hemorrhagic fever with renal syndrome from 2002 to 2005 in Hunan province].
Zhonghua Liu Xing Bing Xue Za Zhi
May 2007
[An epidemiologle investigation of hantaviruses carried by rodent hosts in Hunan province].
Zhonghua Liu Xing Bing Xue Za Zhi
January 2007
Objective: To explore the hantavirus infection and their genotype in rodents in Hunan.
Methods: Hantavirus antigens in the rat lungs from Hunan province were detected by immunofluorescence assay. Partial S and M segment in antigen-positive samples were amplified by RT-PCR, and then sequenced.