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31.
Ana Paula Junqueira-Kipnis Fábio Muniz de Oliveira Monalisa Martins Trentini Sangeeta Tiwari Bing Chen Danilo Pires Resende Bruna D. S. Silva Mei Chen Lydia Tesfa William R. Jacobs Jr André Kipnis 《PloS one》2013,8(11)
The development of a new vaccine as a substitute for Bacillus Calmette–Guerin or to improve its efficacy is one of the many World Health Organization goals to control tuberculosis. Mycobacterial vectors have been used successfully in the development of vaccines against tuberculosis. To enhance the potential utility of Mycobacterium smegmatis as a vaccine, it was transformed with a recombinant plasmid containing the partial sequences of the genes Ag85c, MPT51, and HspX (CMX) from M. tuberculosis. The newly generated recombinant strain mc2-CMX was tested in a murine model of infection. The recombinant vaccine induced specific IgG1 or IgG2a responses to CMX. CD4+ and CD8+ T cells from the lungs and spleen responded ex vivo to CMX, producing IFN-γ, IL17, TNF-α, and IL2. The vaccine thus induced a significant immune response in mice. Mice vaccinated with mc2-CMX and challenged with M. tuberculosis showed better protection than mice immunized with wild-type M. smegmatis or BCG. To increase the safety and immunogenicity of the CMX antigens, we used a recombinant strain of M. smegmatis, IKE (immune killing evasion), to express CMX. The recombinant vaccine IKE-CMX induced a better protective response than mc2-CMX. The data presented here suggest that the expression of CMX antigens improves the immune response and the protection induced in mice when M. smegmatis is used as vaccine against tuberculosis. 相似文献
32.
Physiologic loading of isolated heart muscle 总被引:2,自引:0,他引:2
D L Sulman O H Bing R G Mark S K Burns 《Biochemical and biophysical research communications》1974,56(4):947-951
33.
The effect of caffeine on nitrosoguanidine-induced mutagenesis ofSalmonella typhimurium & nd its P22 and L phages was studied. The detected mutations included phage “clear” mutations, reversions of phage “amber”
mutation, and prototrophic reversions of thehis
−
auxotroph ofSalmonella typhimurium. Neither therecA mutation of the host nor theerf mutation of the phage genome were found to affect the nitrosoguanidine-induced mutagenesis of the phage during vegetative
growth. Beginning with a concentration of 0.2 mg/ml, caffeine decreased the frequency of mutants by 30–60%, attaining a maximum
effect at 1.5 mg/ml and retaining this effect even at higher concentrations. A similar antimutagenic effeot was observed with
the mutagenesis of the host cells. The nitrosoguanidine-induced mutagenesis does not seem to be related to the function of
therecA cell gene or theerf phage gene. The mechanism of mutagenesis by nitrosoguanidine probably has two components, one of them caffeine sensitive,
the other caffeine-resistant. 相似文献
34.
I A Aksenova E M Ter-Sarkisian R D Soífer G Ia Florova L S Iustratova 《Antibiotiki》1984,29(3):179-182
The stability of tylosin, a macrolide antibiotic, in solutions with varying pH and temperature was determined quantitatively. It was shown that tylosin was the most stable at pH about 3.5 and 9.0, which corresponded to the salt and nondissociated forms of the substance. Outside these stability ranges significant inactivation of the antibiotic was observed. The inactivation markedly increased with an increase in the temperature level and the exposure period. Satisfactory correlation between the data on microbiological and spectrophotometric determinations of tylosin in solutions is indicative of the advisability of the use of spectrophotometry in production of tylosin. 相似文献
35.
36.
The annexins are a multifamily of calcium-regulated phospholipid-binding proteins. To investigate the roles of annexins in fiber development, four genes encoding putative annexin proteins were isolated... 相似文献
37.
Melissa Carrillo Suraj Pandey Juan Sanchez Moraima Noda Ishwor Poudyal Luis Aldama Tek Narsingh Malla Elin Claesson Weixiao Yuan Wahlgren Denisse Feliz Vukica Šrajer Michał Maj Leticia Castillon So Iwata Eriko Nango Rie Tanaka Tomoyuki Tanaka Luo Fangjia Marius Schmidt 《Structure (London, England : 1993)》2021,29(7):743-754.e4
38.
39.
40.
Suction volume and filtering efficiency of silver carp (Hypophthalmichthys molitrix Val.) and bighead carp (Aristichthys nobilis Rich.) 总被引:1,自引:0,他引:1
Shuanglin Dong Deshang Li Xuwen Bing Qingfeng Shi Fang Wang 《Journal of fish biology》1992,41(5):833-840
Experiments were conducted to measure the suction volume of silver carp and bighead carp of age 1 + with respiratory chamber, and to calculate the suction volume and the filtering efficiency with respect to changes in concentrations of food particles. Suction volume (B. ml/mouth) and filtering efficiency (E. %) were calculated using the following formula: C 1=C0(1-BE/v)n where C0 and C1 were the concentrations of specific food particles at the beginning and at the end of experiment, respectively, V was the volume (ml) of experimental water, and n was the total number of observation of suction made during the experimental period. The relationships between suction volume (ml/mouth) of age I+ silver carp (Bh) and bighead carp (Ba) and their standard lengths (L, cm) were: B h=0.561L-8.94, Ba= 0.627L-7.48 while those of the fingerlings were: B h= O.l70L-0.837, Ba= 0.157L-0.418. The suction volume of the fingerlings was mainly affected by fish size, the function of temperature between 15 and 25° C being negligible. However, temperature affected filtering rate (filtered volume per unit time) through its effect on filtering frequency. The filtering efficiency of the fishes for rotifers (Brachionus caliciflorus) was 100 per cent. The relationships between filtering efficiency and sizes of food particles smaller than or equal to that of a rotifer were: E h=25.1 ln e.s.d. -13.6, Ea=22.2 In e.s.d. -33.1 where Eh and Ea were filtering efficiency of silver carp and bighead carp, respectively, and e.s.d. was the equivalent spherical diameter (μm) of food particles. 相似文献