| |
qPCR 16S (bacterial) and 18S (human) rDNA results |
| |
11 |
12 |
13 |
14 |
15 |
15a |
15b |
16a |
16b |
17a |
17b |
18 |
18a |
18b |
19 |
20 |
| 16S |
53% |
98% |
7% |
3% |
4% |
10% |
11% |
29% |
62% |
84% |
4% |
21% |
90% |
6% |
10% |
6% |
| 18S |
47% |
2% |
93% |
97% |
96% |
90% |
89% |
71% |
38% |
16% |
96% |
79% |
10% |
94% |
90% |
94% |
Table 1 demonstrates the percent 16S (bacterial) versus 18S (human) ribosomal DNA from each plaque sample. The samples obtained were long ribbons of atherosclerotic plaque obtained from the Silverhawk procedure. For several samples, the entire plaque was homogenized and evaluated. For other samples, the analysis was done at discreet locations (A and B) within the plaque. The findings were quite interesting. Bacterial DNA is not uniformly distributed throughout the plaque as would be expected from random contamination. For example, 16B, 17A, and 18A show overwhelming bacterial (16S) ribosomal DNA as compared to the human DNA found in that area while samples from a different location 16 A, 17 B, and 18 B showed just the opposite. The cycle threshold numbers for the 16S contribution to samples 16B, 17A, and 18A was quite low suggesting very high numbers of bacteria, far more than would be expected from contamination. In fact, sample 12 showed 98% bacterial DNA for the entire homogenized sample. Studies with scanning electron microscopy along with molecular studies suggest that biofilm infections are heterogeneous with the same bacterial species located throughout the infection, yet very condensed in certain portions of the sample and very rarified in other locations of the sample. This is the exact pattern identified for these 10 plaques. |
