Plasma Mitochondrial DNA Concentrations after Trauma

Abstract

species is fragmented, cell-free DNA the size of nucleosomal DNA, mostly derived from cells undergoing apoptosis. As discussed earlier, the source of mutated k-ras DNA in the circulation could be apoptotic cells. Thus, mutated k-ras DNA should be enriched in the fragmented, nucleosomal DNA species relative to the large species found near the sample wells of the gel. Therefore, the DNA isolation method that favors isolation of fragmented DNA should produce a better ratio of k-ras-mutated DNA to wild-type DNA. As shown in Table 1, mutated k-ras was readily detected in the DNA isolated by the G/R method but was detected less frequently in DNA isolated by the Qiagen method from the specimen from the same patient, although more DNA was recovered by the Qiagen method. Another possible contributor to this discrepancy in assay results is the nature of the RE-PCR assay. This is a PCR-based assay, and with more wild-type genomic DNA in the assay, the sensitivity of detection of the mutated DNA is reduced because of interference with the PCR.This study clearly demonstrates that the method chosen for isolation of DNA can contribute significantly to the outcome of mutation detection (in this case, k-ras mutations). It has been suggested that malignant, benign, and even preneoplastic cells often proliferate at abnormal rates, accompanied by an increase in apoptotic cell death (9 -11 ), and that this small, fragmented DNA may accumulate in the circulation. These results further suggest that to enhance assay sensitivity for detection of somatic mutations or epigenetic modifications in circulating DNA for cancer detection, monitoring, or prognosis, a method that can preferentially isolate small DNA should be used.

Mitochondrial and Nuclear DNA in Patients with Severe Polytrauma

“…The diagnosis of nosocomial pneu monia was made based on occurrence of new focal infiltrative changes on the chest X ray in combination with two patterns of following: fever, purulent sputum and (or) leukocytosis, bacteria in aspirate from tracheobronchial tree or blood as determined by gen erally accepted standards [22].…”

Elevated Cell-Free Plasma DNA Level as an Independent Predictor of Mortality in Patients with Severe Traumatic Brain Injury

“…This target is the most studied for this purpose. 31,32,35,40,41,45 The b-globin Taqman system consisted of the amplification primers betaglobin-354F (5¢-GTG CAC CTG ACT CCT GAG GAG A-3¢), betaglobin-455R (5¢-CCT TGA TAC CAA CCT GCC CAG-3¢), and a dual-labeled fluorescent probe beta-globin-402T [5¢-(FAM) AAG GTG AAC GTG GAT GAA GTT GGT GG (TAMRA)-3¢]. 31 The expression of quantitative results as kilogenome-equivalents/L was described previously.…”

“…22,37,40,41,45 The precise mechanism by which DNA is released into the bloodstream remains uncertain, because both necrosis and apoptosis have been observed in this scenario. 46 Further, decreased efficiency of DNA clearance mechanisms after injury may play a role in the increase of cell-free DNA in trauma.…”

Plasma Nuclear DNA and Mitochondrial DNA as Prognostic Markers in Corrosive Injury Patients

“…Recent studies demonstrated that the plasma nuclear DNA concentrations were increased within 20 min of trauma and stroke attack [7, 8]. The concentrations of plasma nuclear DNA and mitochondrial DNA (mtDNA) were associated with the area of the damage tissue in trauma and stroke patients [8, 9]. This study examined the concentrations of the plasma nuclear DNA and mtDNA in corrosive injury patients to determine whether an association with the severity of the disease exists.…”