A limitation of our study is that we did not investigate whether the strains of B. microti isolated from the two cats were human-infecting strains and genetic characterizations of previous samples of B. microti have indicated that both zoonotic and presumed nonzoonotic strains can cocirculate in the same species of rodents [ 23].
In the four-point bending beam, the PCSSs in compressive zone and tensile zone can be used to presume the strain variation by considering the gauge factor obtained from the free PCSS.
The mean number of days needed to form a pellicle was lower in the persistent strains than in the presumed non-persistent strains, both when including all the defined strains (2.4 vs 3.5, Students' t test, p < 0.05), and when testing the serovar Agona and serovar Montevideo strains only (2.4 vs 3.6, Students' t test, p < 0.05).
We got different response in the lungs and in the eye even though it is presumed that the strain of mycobacterium tubercle bacilli causing infection in the lungs would also be the causative bacilli in the left eye.
A magnified part of the same film is shown in Figure 3c', where the arrow (x) indicates the film-degrading hyphae, which we presumed to be strain B47-9, along with other hyphae that did not degrade the film, designated by arrow (y), which were believed to be soil-derived microorganisms.
We do not know for certain if they require prophylactic treatment to prevent infection or treatment of LTBI with a presumed drug-resistant strain, or if the risks of potential side-effects and use of complicated drug regimens outweigh the benefits.
Also in this comparison, the persistent strains displayed a higher OD595 than the presumed non-persistent strains (mean OD595 1.01 vs 0.69, Students' t test, p = 0.05).
Also in this comparison, the persistent strains were better biofilm producers than the presumed non-persistent strains, indicating that the observed correlation between persistence and biofilm production is not due to a confounding effect of serovar.
The persistent strains had higher OD595 (mean 1.01) than the presumed non-persistent strains (mean 0.44) (Students' t test, p < 0.05).
Based on these criteria, the study included seven persistent strains (four serovar Agona, three serovar Montevideo) and 14 presumed non-persistent strains (two serovar Agona, three serovar Montevideo, three serovar Senftenberg, six serovar Typhimurium).
This hypothesis is further supported by the results showing that the persistent strains clearly were better biofilm producers in both test systems than the presumed non-persistent strains.
