ABSTRACT
Objective@#To establish a TaqMan-MGB probe-based real-time fluorescence RT-PCR assay for avian influenza H5N6 virus used in rapid diagnosis for suspected cases and surveillance for outer environment of live poultry markets.@*Methods@#Based on the conservative sequences of avian influenza H5N6 virus for HA and NA gene published on GenBank, specific primers and TaqMan-MGB probes were designed to develop and optimize for the dual real-time RT-PCR assay. Specificity, sensitivity, repeatability and comparison tests were carried out.@*Results@#This dual real-time RT-PCR detection can be completed within 80 minutes. There was no cross-reaction with other subtypes of influenza virus and common respiratory pathogens. The minimum detection limit could be up to 10 copies/reaction. The correlation coefficient of standard curve for the gene of H5 and N6 were 0.999 and 0.993, and the coefficients of variation for cycle threshold were range from 0.151%-0.549%and 0.213%-0.575%, respectively. The positive and negative coincidence rates of the validation test were 100%.@*Conclusions@#This TaqMan-MGB probe-based dual real-time RT-PCR for avian influenza H5N6 virus was rapid, specific and sensitive. It will have a good use in early emergency detection of suspected cases and continuous monitoring of external environment in live poultry trade market.
ABSTRACT
We analyzed genetic evolution characteristics of avian influenza A (H7N9) virus isolated in Zhaoqing,China,2014-2016.Nucleic acid were extracted and sequenced from 17 samples of H7N9 positive cases in Zhaoqing.Genetic characteristics of homology and important amino acid sites were analyzed by using BioEdit5.0 and MEGA6.0.The evolutionary trees were constructed by Neighbor-Joining and the referenced sequences were downloaded from GenBank,Eight nucleic acid fragments from 7 strains of H7N9 viruses were successfully generated.The highest homology was found in HA gene with A/chicken/Dongguan/695/2014(H7N9),and NA gene with A/chicken/Dongguan/1075/2014(H7N9).The internal genes were high homology with avian H7N9 and H9N2 virus from Dongguan and Shenzhen in Guangdong,China.The HA and NA genes were directly evolved in the Pearl River Delta evolution branch with the H7N9 sequences from the cities of Dongguan,Guangzhou and Shenzhen,while the sequences from the provinces of Anhui,Zhejiang,and Jiangsu were in the Yangtze River Delta evolution branch.There were 2 alkaline amino acids in cleavage site of HA,2 mutations (G186V and Q226L) in the crucial sites related with the receptor of HA protein,1 mutation (E627K) in PB2 protein,and 1 drug resistance mutation (S31N) in M2 protein.And no evidence of neuraminidase resistance in NA protein was found.In conclusion,the H7N9 virus for human infection in Zhaoqing may originate from avian H7N9 and H9N2 viruses,which circulated in the Pearl River Delta region of Guangdong from 2013 to 2014.The mutations of G186V,Q226L and E627 K might be related with high susceptibility to human beings.
ABSTRACT
Objective To envaluate the accuracy of Photoplethysmograph pulse wave in monitoring stress reaction to harmful stimulation. Methods Patients (n=75) were randomly assigned to three groups according to the dosages of fentanyl that were administrated ( 4, 5 and 6 g/kg were given to F4, F5, F6 group respectively (n=25) in each group. Heart rate (HR), Systemic blood pressure (SBP), Diastolic blood pressure (DBP), SpO2, the skin temperature of finger, perfusion index (PI), epi?nephrine(E) and Norepinephrine (NE) were recorded at following time points:just in operation room (T1), 2 min after induc?tion (T2), at intubation (T3),1 min (T4) and 5 min (T5) after intubation. And the PPGPW was printed and measured at the same time points. Results PPGA and PI were significantly increased while E and NE were significantly decreased in T2 and T5, compared with those baseline at T1 (P < 0.05). At T3, PPGA and PI were significantly decreased while NE markedly in?creased in group F4 and F5 compared to T1. At T3, E in group F4 were remarkably increased h while E in group F5 were of no obvious changed, compared with those at T1(P<0.05). PPGA and PI increased while E and NE decreased in group F6 at T2, T3 ,T4 and T5 compared with those at T1 (P<0.05). In summary, PI was negatively correlated with plasma E and NE while PP?GA was negatively correlated with plasma E and NE .Conclusion PPGA and PI are negatively associated with intensity of stress response. And they can reflect the stress reaction during the induction period of intravenous anesthesia accurately.