Browsing by Subject "DNA analysis"

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    EUS-guided Fine Needle Aspiration-based Clues to Mistaken or Uncertain Identity: Serous Pancreatic Cysts
    (Elsevier, 2023) Yip-Schneider, Michele T.; Muraru, Rodica; Kim, Rachel C.; Wu, Howard H.; Sherman, Stuart; Gutta, Aditya; Al-Haddad, Mohammad A.; Dewitt, John M.; Schmidt, C. Max; Surgery, School of Medicine
    Background/objectives: Pancreatic serous cystic neoplasms (SCN) present a diagnostic challenge given their increasing frequency of detection and benign nature yet relatively high rate of misdiagnosis. Here, imaging and analyses associated with EUS-guided fine-needle aspiration (EUS-FNA) are evaluated for their ability to provide a correct preoperative diagnosis of SCN. Methods: A surgical cohort with confirmed pathological diagnosis of SCN (n = 62) and a surveillance cohort with likely SCN (n = 31) were assessed for imaging (CT/MRI/EUS) and EUS-FNA-based analyses (cytology/DNA analysis for Von Hippel-Lindau [VHL] gene alterations/biomarkers). Results: In the surgical cohort, CT/MRI and EUS respectively predicted SCN in 4 of 58(7%) and 19 of 62(31%). Cyst fluid cytology and VHL alterations predicted SCN in 1 of 51(2%) and 5 of 21(24%), respectively. High specificity cyst fluid biomarkers (vascular endothelial growth factor [VEGF]/glucose/carcinoembryonic antigen [CEA]/amylase) correctly identified SCN in 25 of 27(93%). In the surveillance cohort, cyst fluid biomarkers predicted SCN in 12 of 12(100%) while VHL alterations identified SCN 3 of 10(30%). Conclusion: High specificity cyst fluid biomarkers provided the most sensitive means of diagnosing SCN preoperatively. To obtain a preoperative diagnosis of SCN at the highest level of certainty, a multidisciplinary approach should be taken to inform appropriate SCN management.
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    Molecular Genetic Methods for Forensic Entomology
    (CRC Press, 2019) Stevens, Jamie R.; Picard, Christine J.; Wells, Jeffrey D.
    A preservative solution containing formaldehyde should not be used if it can be avoided, as formalin can interact with deoxyribonucleic acid (DNA), making subsequent molecular analyses difficult. Some forensic entomologists recommend killing maggots by blanching in hot water; this technique does not appear to hinder any subsequent DNA analysis. Maggots found in the absence of a corpse may still have the victim’s tissue in their gut. Such specimens must be killed and preserved immediately, otherwise the evidence may be digested and lost. There is little doubt about the need for accurate specimen identification in forensic entomology. Intraspecific variation in DNA sequence is commonly observed, so an unknown specimen will often not exactly match the genotype of a reference specimen. Ribonucleic acid analysis can reveal the genes that were active within a tissue sample at the time it was processed.