ABSTRACT
To investigate the biological characteristics of mycobacteriophage Leo and its bactericidal effect on Mycobacterium tuberculosis for cocktail therapy ,we observed mycobacteriophage plaques after amplifying phage by double‐layer agar plate method .The morphological characteristics were observed by electron microscopy .Mycobacteriophage Leo DNA was extracted and then digested by restriction enzyme to identify the nucleic acid type .Leo was amplified in different multiplicity of infection (MOI) to find the optimal MOI and the minimum MOI .One step growth experiment was carried out to find the latent period and burst size of Leo .The frequency of Mycobacterium smegmatis mutation treated with mycobacteriophage Leo was inspected by the endpoint titration test .The effect of temperature and alcohol on Leo survival was surveyed .The ability of Leo to crack host bacteria at different pH values was examined .The effect of Leo on Mycobacterium tuberculosis was determined by bacteri‐cidal assay .Results showed that the Leo plaque was round and transparent with a diameter of 1 .5 nm .Leo has an isometric head (70 ± 3 .0 nm in diameter) and a flexible tail (211 ± 31 .7 nm in length) .Its genome could be digested by restriction en‐zyme of Hind Ⅲ and Bgl Ⅰ .The optimal MOI and the minimum MOI of Leo were 0 .000 01 and 0 .000 1 ,respectively .The mutation frequency was 10-7 .The latent period was 150 min ,and the burst size was 74 .Leo could not only crack host bacteria in solid medium at pH 7 .4 but also at pH 5 .0 .After 72 hours ,the amount of Mycobacterium tuberculosis in Leo group was less than that in control group (P<0 .05) .In conclusion ,Leo has a bactericidal effect on Mycobacterium tuberculosis and could be a candidate of phage cocktails .
ABSTRACT
BACKGROUND:Many present scholars do a large number of researches on anatomical structure in the thoracic costotransverse binding region so as to seek a safe pathway of screw entrance besides posterior thoracic approach outside pedicle, but their conclusions are controversial. OBJECTIVE: To measure the anatomical and radiological structures of costotransverse groove and to explore the safe pathway of screw implantationvia posterior thoracic vertebra outside pedicle of vertebral arch. METHODS:Eight embalmed adult cadaveric thoracic spines were harvested with the medial 5.0-6.0 cm of rib. Intercostal soft issue and parietal pleura were left intact. Al nonstructural soft issue was removed. Specimens were scanned with CT, and three-dimensional reconstruction was performed. The angles of the costotransverse groove were obtained. Anatomical analysis was performed in specimens. The distance from the superior limit of the rib superiorly to the superior limit of adjacent transverse process and the distance from the inferior limit of the rib inferiorly to the inferior limit of adjacent transverse process were measured. RESULTS AND CONCLUSION:There exists a costotransverse groove between rib and transverse process. Both distance from the superior limit of the rib superiorly to the superior limit of adjacent transverse process and the distance from the inferior limit of the rib inferiorly to the inferior limit of adjacent transverse process of T6-10 were significantly larger than other levels (P < 0.05). The costotransverse groove was most obvious at T6-10 segments. Results verified that adult costotransverse groove directed to vertebra, and provided a new idea for the pathway of screw implantationvia posterior thoracic vertebra outside pedicle.
ABSTRACT
Objective To investigate the clinical effects of bridge type bone plate series designed by ourselves. Methods A sort of bridge type bone plate series were designed according to mechanics and structure of bridges. They were used in the internal fixation of 12 shinbone fractures and 41 fractures of middle and lower parts of thighbone. The treatment results were followed up and statistics was done to evaluate fracture healing at 8, 12, 16, 20, and 24 weeks respectively. Results Of the 53 fractures, 48 achieved clinical union and 27 solid union within 12 weeks, 51 reached clinical union and 47 solid union within 16 weeks, 53 reached clinical union and 52 solid union within 20 weeks, and all reached solid union within 24 weeks. Conclusion The self designed bridge type bone plate series are a nice internal fixation device for clinical treatment of fractures.