Localized in situ amplification (LISA): a novel approach to in situ PCR.

Amplification of specific gene target sequences has become a routine molecular procedure in a variety of laboratories. When coupled with either a direct or indirect method of detecting amplified product, in situ amplification offers an extremely powerful investigative tool. We describe a protocol for a localized in situ amplification (LISA) reaction that includes tissue-culture cloning rings and allows for the amplification of gene target sequences in specific regions of paraffin-embedded tissue sections. Digoxigenin-11-dUTP was added to the amplification reaction and thus incorporated into the amplified products, providing a mechanism by which direct nonisotopic detection could be performed. To demonstrate the approach, LISA was performed on known positive Pneumocystis carinii rat lung tissues, with primers specific for the P. carinii rRNA gene sequence.

Hypersegmentation of neutrophils in the cerebrospinal fluid: report of a case with hematologic correlation and review of the literature.

Hypersegmented neutrophils can occasionally be seen in the cerebrospinal fluid (CSF) of patients with acute pyogenic meningitis, and rarely as an artifact of cytocentrifugation. We report a case of florid neutrophil hypersegmentation in cytocentrifuged CSF specimens from a patient presenting with anemia and mental status changes. Megaloblastic anemia was excluded by a thorough hematologic evaluation, and the patient was later found to have an epidural abscess. The striking hypersegmentation is attributed to the combined effects of meningeal infection and cytocentrifugation, and a review of the available limited literature on cytomorphologic alterations in CSF cells, specifically neutrophils, is presented.

Prognostic factors in the recurrence of stage I and II squamous cell cancer of the oral cavity.

Stage I and II squamous cell cancers of the oral cavity have a high recurrence rate given their size and relative amenability to surgical resection. It has been suggested that one way to decrease this recurrence rate is to augment the surgical resection of these tumors with either elective neck dissection or radiation therapy. However, this would expose a significant number of patients to the unnecessary morbidity associated with either of these modalities. In an attempt to identify those patients most at risk for recurrence, we retrospectively determined the clinical and histologic factors that were associated with recurrence in 49 patients with stage I and II oral cavity cancer. Multiple regression analysis revealed that when various interactions between variables were controlled for, only the presence of a positive surgical margin or a tumor depth greater than 5 mm was significantly associated with recurrence. Each individually increased the likelihood of recurrence almost threefold.