False-positive reverse transcriptase polymerase chain reaction screening for SARS-CoV-2 in the setting of urgent head and neck surgery and otolaryngologic emergencies during the pandemic: Clinical implications.

Background: No reports describe falsepositive reverse transcriptase polymerase chain reaction (RT-PCR) for novel coronavirus in preoperative screening.

Methods: Preoperative patients had one or two nasopharyngeal swabs, depending on low or high risk of viral transmission. Positive tests were repeated.

Mortality increases for octogenarians undergoing esophagogastrectomy for esophageal cancer.

Background: As the general population ages, it becomes increasingly important to understand the potential contribution of chronologic age to mortality after esophagectomy. Because this risk is poorly defined, we sought to determine whether extreme age (>80 years) is an independent risk factor after esophagectomy.

Methods: We analyzed a prospectively maintained, single-institution database of 858 consecutive patients who underwent esophagectomy between January 1996 and May 2005.

Telomere length assessment in tissue sections by quantitative FISH: image analysis algorithms.

Background: Telomeres are tandem repeated DNA sequences at the ends of every chromosome, which cap, stabilize, and prevent chromosome fusions and instability. Telomere regulation is an important mechanism in cellular proliferation and senescence in normal diploid and neoplastic cells. Quantitative methods to assess telomere lengths are essential to understanding how telomere dynamics play a role in these processes.

Chromosomal instability in pancreatic ductal cells from patients with chronic pancreatitis and pancreatic adenocarcinoma.

Pancreatic adenocarcinoma is a disease with high mortality for which chronic pancreatitis confers a markedly increased risk. We hypothesize that chromosome instability and genomic damage occur in pre-neoplastic pancreatic ductal epithelium, and that this damage may be related to oxidative stress. We used dual-color fluorescence in situ hybridization with centromere probes and locus-specific arm probes for chromosome arms 11q, 17p, and 18q to identify genomic instability in cultures of normal-appearing human pancreatic ductal epithelium from normal organ donor controls compared to patients with chronic pancreatitis or pancreatic adenocarcinoma.

Chromosomal instability in ulcerative colitis is related to telomere shortening.

Ulcerative colitis, a chronic inflammatory disease of the colon, is associated with a high risk of colorectal carcinoma that is thought to develop through genomic instability. We considered that the rapid cell turnover and oxidative injury observed in ulcerative colitis might accelerate telomere shortening, thereby increasing the potential of chromosomal ends to fuse, resulting in cycles of chromatin bridge breakage and fusion and chromosomal instability associated with tumor cell progression. Here we have used quantitative fluorescence in situ hybridization to compare chromosomal aberrations and telomere shortening in non-dysplastic mucosa taken from individuals affected by ulcerative colitis, either with (UC progressors) or without (UC non-progressors) dysplasia or cancer.

Flow cytometric analysis of the cell cycle phase specificity of DNA damage induced by radiation, hydrogen peroxide and doxorubicin.

We have optimized a flow cytometric DNA alkaline unwinding assay to increase the sensitivity in detecting low levels of DNA damage (strand breaks and alkali-labile sites) and to permit the measurement of the extent of DNA damage within each cell cycle compartment. The lowest gamma radiation dose that induced detectable DNA damage in each cell cycle phase of HeLa and CEM cells was 10 cGy. The lowest H(2)O(2) concentration that induced detectable DNA damage in each cell cycle phase was 0.