Role Of BSR1526 And BSR1955 In Virulence Of Brucella And The Prevention And Control Of Brucellosis

Brucellosis as a zoonotic infectious disease,Widespread in the world,serious harm to human health and animal husbandry development.People were infected mainly by contact with sick livestock and their products closely.Usually by cuts,abrasions,oral mucosa,nasal,conjunctival,genital tract,even skin without damage.With the development of animal husbandry and the rapid increase in the number of new cases of animal brucellosis,The risk of human brucellosis is increasing.Brucellosis is a worldwide public health problem which Caused widespread concern in the international and domestic.Because of the study on pathogenic mechanism of Brucella is not enough.The measures of prevention and control brucellosis Can not meet the actual needs of the current epidemic prevention.Brucella is meant to be a intracellular bacteria model for the study of intracellular bacterial infection.Previous studies have shown,The most important virulence characteristics of Brucella are its intracellular survival.Intracellular survival adaptability can Help us to understand the pathogenic mechanism of Brucella.Brucella can cause the natural host of the reticuloendothelial system persistent infection,The Mainly measures control end prevent brucellosis were Census and elimination.In this study,two of these sRNAs in Brucella had been chosen to investigated virulence characteristics and adaptation to the environment in bacteria.Present situation of brucellosis prevention and control had been investigated,and the clinical effect of Monitoring and Clean had been evaluated too.1.The role of non coding sRNA BSR1526 in intracellular survival and virulence of BrucellaSingle strand sequencing based on RNA in 16M Predict a new sRNA BSR1526.BSR1526 transcription was verified by Northern blot and RT-PCR.BSR1526 was verified by Northern blot and its transcription under stress conditions was verified by RT-PCR.BSR1526 got a high levels of transcription under acidic conditions than any other conditions.The mutant strains of BSR1526 were constructed by fusion PCR,and verificated there was no transcription in Deletion strain by RT-PCR.BSR1526 was inserted into the plasmid pBBR1-MCS4,which transformed into Brucella melitensis 16M to generate the overexpression strain 16M-BSR1955.Deletion or overexpression of BSR1526 affected the growth of Brucella in vitro and the intracellular survival ability.The 16M-?BSR1526 showed reduced survival under heat shock,oxidative stress and acidic conditions,and significant reduction in mice spleen at the 14d,indicating that BSR1526 influenced the virulence of Brucella.In summary,small noncoding RNA BSR1526 affects intracellular survival ability and the virulence of Brucella.2.The role of non coding sRNA BSR1955 in intracellular survival and virulence of BrucellaThe mutant strains of BSR1955 were constructed by fusion PCR.Verificated there was no transcription in Deletion strain by RT-PCR.BSR1955 was inserted into the plasmid pBBR1-MCS4,which transformed into Brucella melitensis 16M to generate the overexpression strain 16M-BSR1955.Results mutant BSR1955 can slowdown Brucella growth.Indicating that BSR1955 is involved in Brucella regulation of growth rate.The virulence related phenotypes of the mutant and overexpression strains was analyzed.16M-?BSR1955 showed increased survival under high salt and osmotic stress,and significant increase in mice at 28 and 45d,indicating that BSR1955 influenced the virulence of Brucella.Conclusion Small noncoding RNA BSR1955 affects intracellular survival ability of Brucella melitensis 16M.The ability adapting to high salt or osmotic stress and virulence in mice of mutant BSR1955 strain was increased.3.Investigation on current situation of brucellosis prevention and control in the north of SichuanInvestigation on the construction of veterinary epidemic prevention team shows Professionals veterinarian were deficient in grass-roots units,Educational structure in good,but low education relatively large in Some counties,75.54%grass-roots veterinary staff are veterinary related professional graduates,Most grass-roots veterinary staff are primary or mid-level in professional ranks and titles.Only 1.05%of grass-roots veterinary staff obtain the Veterinary Certificate.According to the age structure of,30.36%of the workers are over the age of 50,Reserve talent reserve is relatively insufficient.The quantity of Village Animal epidemic prevention coordinator can not meet the requirements,56.90%Village Animal epidemic prevention coordinator are the age of 50-60,8.24%Village Animal epidemic prevention coordinator are over the age of 60,Aging becomes the serious problem of the Village Animal epidemic prevention coordinator staff.Veterinary staff in the city have been test about professional knowledge,Results shows 19.75%veterinarian in town and 40.12%Village Animal epidemic prevention coordinator can not Pass the test.According to the monitoring statistics in recent years,city level lab take the Brucellosis monitoring chiefly before 2013.The city began a large area of Brucellosis monitoring work from 2014,In the fourth quarter of 2015,the total numbers of Brucellosis monitoring samples is too low that only about 1.77%of the total sheep population.Governments did not put enough attention to brucellosis prevention and control,and about brucellosis propaganda.Live livestock which allocated very frequent,haven't pay enough attention to the health and epidemic prevention in the process of transportation,brucellosis quarantine work is difficult to carry out,supervision can not keep up with the pace of development of the industry.The top-level design is not enough,and the disposition of positive sheep in brucellosis rarely,professional and technical personnel in veterinary laboratories,can not meet the needs of the brucellosis monitoring.4.Purification pilot and effect analysis of brucellosis in the north of SichuanComprehensive monitoring and purification measures of brucellosis purification had been set based on the overall situation of the city,and pilot in a country.purification.Serological monitoring of brucellosis shows,a large number of sheep have been infected with Brucella.1181 serum samples have been detected that 55 serum samples were brucellosis antibody positive,the total positive rate was 4.66%.The number of brucellosis antibody positive gradually reduce during the purification process.In the first phase of monitoring,positive samples were 463 and the total positive rate of brucellosis was 34.48%,significantly higher than in the 4.66%census monitoring.The positive rate gradually decreased,that the second phase was 9.53%,the third phase was 2.78%,the fourth phase was 1.75%after harmless treatment.The final stage was 0.78%.The number of brucellosis antibody positive sheep decreased significantly.These measures have Obvious effect in brucellosis purification.After the above measures were taken,the total positive rate of brucellosis was 0.91%significantly lower than the average rate 4.12%which tested in August 2016.