ABSTRACT
Objective To evaluate the effects of intravenous injection of different blood components containing Babesia microti on B. microti infection in mice. Methods Healthy mice were infected with B. microti, and then blood samples were collected from the mouse orbit to prepare whole blood, serum-free blood components and pure red blood cells containing B. microti. Twenty seven BALB/c mice were divided into three groups, including the whole blood group, the serum-free blood component group and the pure red blood cell group, of 9 mice in each group, and then, each group was divided into three subgroups, of 3 mice in each subgroup, which were injected with 100 μL of blood components containing B. microti at concentrations of 9.00, 0.90, 0.09 B. microti parasites/μL (900, 90, 9 B. microti parasites) via the tail vein, respectively. Blood samples were collected from the mouse tail tip every other day since one day post-injection to prepare thin blood smears. Following Giemsa staining of blood smears, B. microti infection was identified in red blood cells using microscopy. Results Following injection of 900 B. microti parasites, B. microti was identified in the peripheral blood in the whole blood group and the serum-free blood component group 3 days post-injection, and the density of B. microti parasites started to increase 15 days post-injection and peaked 21 days post-injection, with 2.21% and 1.76% rates of B. microti infection in red blood cells, respectively. Subsequently, the density of B. microti parasites declined, and the percentage of B. microti infection in red blood cells tended to be 0 31 days post-injection. During the study period, no B. microti was found in the peripheral blood in the pure red blood cell group. Following injection of 90 B. microti parasites, B. microti was identified in the peripheral blood in the whole blood group 3 days post-injection, and the density of B. microti parasites increased 15 days post-injection and peaked 21 days post-injection, with a 1.35% rate of B. microti infection in red blood cells, while the percentage of B. microti infection in red blood cells tended to be 0 31 days post-injection. During the study period, no B. microti was detected in the peripheral blood in the serum-free blood component group or the pure red blood cell group. Following injection of 9 B. microti parasites, no B. microti was detected in the peripheral blood in the whole blood group, the serum-free blood component group or the pure red blood cell group. Conclusion Blood components and dose of B. microti parasites may affect intravenous injection of B. microti injection in mice, and transfusion of blood components may case a risk of Babesia infection.
ABSTRACT
Objective To evaluate the effects of intravenous injection of different blood components containing Babesia microti on B. microti infection in mice. Methods Healthy mice were infected with B. microti, and then blood samples were collected from the mouse orbit to prepare whole blood, serum-free blood components and pure red blood cells containing B. microti. Twenty seven BALB/c mice were divided into three groups, including the whole blood group, the serum-free blood component group and the pure red blood cell group, of 9 mice in each group, and then, each group was divided into three subgroups, of 3 mice in each subgroup, which were injected with 100 μL of blood components containing B. microti at concentrations of 9.00, 0.90, 0.09 B. microti parasites/μL (900, 90, 9 B. microti parasites) via the tail vein, respectively. Blood samples were collected from the mouse tail tip every other day since one day post-injection to prepare thin blood smears. Following Giemsa staining of blood smears, B. microti infection was identified in red blood cells using microscopy. Results Following injection of 900 B. microti parasites, B. microti was identified in the peripheral blood in the whole blood group and the serum-free blood component group 3 days post-injection, and the density of B. microti parasites started to increase 15 days post-injection and peaked 21 days post-injection, with 2.21% and 1.76% rates of B. microti infection in red blood cells, respectively. Subsequently, the density of B. microti parasites declined, and the percentage of B. microti infection in red blood cells tended to be 0 31 days post-injection. During the study period, no B. microti was found in the peripheral blood in the pure red blood cell group. Following injection of 90 B. microti parasites, B. microti was identified in the peripheral blood in the whole blood group 3 days post-injection, and the density of B. microti parasites increased 15 days post-injection and peaked 21 days post-injection, with a 1.35% rate of B. microti infection in red blood cells, while the percentage of B. microti infection in red blood cells tended to be 0 31 days post-injection. During the study period, no B. microti was detected in the peripheral blood in the serum-free blood component group or the pure red blood cell group. Following injection of 9 B. microti parasites, no B. microti was detected in the peripheral blood in the whole blood group, the serum-free blood component group or the pure red blood cell group. Conclusion Blood components and dose of B. microti parasites may affect intravenous injection of B. microti injection in mice, and transfusion of blood components may case a risk of Babesia infection.
ABSTRACT
Objective To understand the changes in body weight,spleen weight and complete blood cells in BALB/c mice infected with Babesia microti.Methods For the infection group,six weeks old BALB/c mice were injected intraperitoneally with a dose of 100μL of B.microti infected blood(20％RBC infection rate,each mouse).For the determination of the progres-sion of B.microti infection up to 28 days of the infection,the microscopic visualization of thin blood smears of tail blood stained with Giemsa staining was performed in the infection group.The experiment was carried out at different intervals on days 0,7,14,21,and 28 after the infection,respectively.The mice were sacrificed,and spleens were collected and weighed,and the body weight of the mice was also determined.The blood cells of the mice were analyzed by using Mindray BC-5300 Vet animal automatic hematology analyzer.Results On the first day after the infection,B.microti was visualized in RBC of the infection group.The significantly highest infection rate(55％)appeared on the seventh day of the infection,and then steadily decreased;the mice attained the latent infection phase on the 28th day post-infection,when the parasite could not be visualized in the pe-ripheral blood.The mice in the infected group acquired a significantly lowest body weight on the 7th day of the infection,and then gradually returned to normal.The weight of the spleen was the significantly highest on the 14th day of the infection,and then consistently decreased.On the 28th day of infection,the spleen weight was still higher than that of the control group.There were no significant changes in the number of white blood cells(WBC),lymphocytes,and eosinophils in the infected mice;and altered levels were all within the normal mouse reference range.The number of red blood cells,hemoglobin,and platelet count in the infected mice were decreased to the lowest level when the B.microti infection rate achieved to the highest,and then gradu-ally returned to the normal levels.Conclusions B.microti infection can cause body weight loss,splenic weight gain,and re-duction in the number of erythrocytes and platelets in whole blood of the mice.Besides,the whole blood cell analyzer has a diag-nostic significance in the identification of babesiosis.
ABSTRACT
<p><b>OBJECTIVES</b>To develop a new method for amplifying and sequencing the full-length of HBV genome.</p><p><b>METHODS</b>A pair of primers located at the nick region of HBV molecule and a thermostable polymerase with high fidelity and sensitivity were used. After cloning the PCR products into a plasmid, the sequences of HBV genome were analyzed.</p><p><b>RESULTS</b>The full-length of HBV genome were acquired using this method. The sensitivity and fidelity of the new method were also analyzed. The least quantity of initial templates was 10(2) and the artificial mutation rate was 1.2 bp/kb.</p><p><b>CONCLUSION</b>This method can be used in amplification and sequence analysis of the full-length of HBV genome on a large scale.</p>