OBJECTIVE To evaluate a hypervariable octameric oligonucleotide fingerprints (HOOF-Prints) assay for identification of and discrimination between wild-type and vaccine strains of Brucella melitensis.
SAMPLEBrucella melitensis vaccine strain M5 and wild-type strain M43.
PROCEDURES 8 pairs of primers (alterable, octameric nucleotides) were designed on the basis of a biological analysis of 8 flanking sequences in the DNA of B melitensis. The HOOF-Prints technique was used to identify wild-type and vaccine strains of B melitensis. Phylogenetic analysis of short, polymorphic fragments of DNA from B melitensis strains M5 and M43 was performed.
RESULTS Variable-number tandem repeat DNA segments of B melitensis vaccine strain M5 and wild-type strain M43 were successfully amplified by means of PCR assay. All target gene fragments ranged in size from 100 to 300 bp. Separate phylogenetic analysis of each Brucella strain revealed considerable differences between the vaccine and wild-type strains.
CONCLUSIONS AND CLINICAL RELEVANCE The results of this study suggested the HOOF-Prints assay may be useful for discriminating vaccine strains of B melitensis from wild-type strains. This ability could allow discrimination between animals that are seropositive because of vaccination against B melitensis and those that are seropositive because of B melitensis infection and could decrease the likelihood of importing Brucella-infected animals.
Histone deacetylases (HDACs) are the key regulators involved in the process of embryo development and tumor progression and are often dysregulated in numerous disordered cells, including tumor cells and somatic cell nuclear transfer (SCNT) embryos. Psammaplin A (PsA), a natural small-molecular therapeutic agent, is a potent histone deacetylase inhibitor (HDACi) that alters the regulation of histone.
Approximately 2,400 bovine parthenogenetic (PA) embryos.
To investigate the effect of PsA on bovine preimplanted embryos, we analyzed the preimplantation development of PA embryos treated with PsA in this study.
The blastocyst formation rate of bovine PA embryos decreased sharply with an increase in concentration and duration. Furthermore, the expression of the pluripotency-related gene Nanog was decreased, and the inhibitory effects on histone deacetylases 1 (HDAC1) and DNA methylation transferase 1 (DNMT1) were observed in bovine PA embryos. The acetylation level of histone H3 lysine 9 (H3K9) was enhanced by a PsA treatment of 10 μM for 6 h, while the DNA methylation appeared unchanged. Interestingly, we also found that PsA treatment enhanced the intracellular reactive oxygen species (ROS) generation and decreased the intracellular mitochondrial membrane potential (MMP)- and superoxide dismutase 1 (SOD1)-induced oxidative stress. Our findings improve the understanding of HDAC in embryo development and provide a theoretical basis and reproduction toxicity evaluation for the application of PsA.
These results indicate that PsA inhibits the development of bovine preimplantation PA embryos, supplying data for the PsA clinical application concentration to avoid reproductive toxicity. In addition, the reproduction toxic effect of PsA may be modulated through increased oxidative stress on the bovine PA embryo, suggesting that PsA in combination with antioxidants, for example, melatonin, might be an effective clinical application strategy.
Orthohantaviruses (genus Orthohantavirus, family Hantaviridae of order Bunyavirales) are rodent-borne viruses causing 2 human diseases: hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), which are mainly prevalent in Eurasia and the Americas, respectively. We initiated this study to investigate and analyze the Orthohantaviruses infection in rodent reservoirs and humans in the Hubei Province of China from 1984 to 2010.
The study included 10,314 mouse and 43,753 human serum samples.
In this study, we analyzed the incidence of Orthohantavirus infection in humans and observed changes in rodent reservoirs in Hubei Province.
The results indicated that although the incidence of HFRS declined from the 1990s, the human inapparent infection did not decrease dramatically. Although elements of the disease ecology have changed over the study period, Apodemus agrarius and Rattus norvegicus remain the major species and a constituent ratio of Rattus norvegicus increased. Rodent population density fluctuated between 16.65% and 2.14%, and decreased quinquennially, showing an obvious downward trend in recent years. The average orthohantaviruses-carrying rate was 6.36%, of which the lowest rate was 2.92% from 2006 to 2010. The analysis of rodent species composition showed that Rattus norvegicus and Apodemus agrarius were the dominant species over time (68.6% [1984 to 1987] and 90.4% [2000 to 2011]), while the composition and variety of other species decreased. The density of rodents was closely related to the incidence of HFRS (r = 0.910, P = .032).
Our long-term investigation demonstrated that the occurrence of HFRS is closely related to rodent demographic patterns. Therefore, rodent monitoring and rodent control measures for prevention against HFRS in Hubei are warranted.