Validation of the AmpFlSTR Profiler Plus PCR amplification kit for use in forensic casework.

According to TWGDAM guideline 4.5 (1), prior to implementing a new DNA analysis procedure or an existing DNA analysis procedure developed by another laboratory, the forensic laboratory must first demonstrate reliability of the procedure in-house. Seven phases were designed to validate the use of the AmpFlSTR Profiler Plus PCR Amplification Kit, as well as the PE Applied Biosystems 310 Genetic Analyzer. This report summarizes the results obtained for each of the seven phases of the validation study which included the following evaluations: polymer, reproducibility, sensitivity, stutter, precision, mixtures and nonprobative casework.

A simple two-dye basic stain facilitating recognition of mitosis in plastic embedded tissue sections.

Semithin sections of buccal and palatal mucosa fixed in 2.5% glutaraldehyde followed by 1% osmium and embedded in Durcupan (an araldite-based resin) were stained with 2% malachite green in 50% ethanol at 80 C and poststained in 0.05% crystal violet in Sorensen's phosphate buffer (pH 6.4) at 45 C. Nuclear envelopes and chromatin stain vivid purple in contrast to the surrounding green cytoplasm and cell borders. Chromosomes of dividing cells stain bluish violet. Nucleoli, depending on their level in the epithelium, stain differing shades of greenish blue. The distinct and differential staining of each of these components facilitates recognition of mitoses in oral epithelium, where the small size and crowding of cells in the proliferative compartment renders more conventional stains for plastic sections inadequate.

Zinc concentration in normal and healing gingival tissues in beagle dogs.

Previous studies have shown that the administration of zinc (Zn) may enhance the healing of gingival and other wounds. This study was undertaken to determine if Zn concentration ([Zn]) is increased in healing gingival tissues and if oral supplementation of Zn would result in a local increase in [Zn] within these tissues. On Day 0, biopsies were obtained from the maxillary left buccal gingiva of each of 10 beagle dogs. Gingival biopsies were taken from the healing original biopsy sites on Day 14. On Day 15, oral supplementation of Zn gluconate (250 mg/day, equivalent to 32.5 mg of elemental Zn) was begun in seven dogs. Three dogs remained as unsupplemented controls. Two weeks later (Day 28), normal gingival biopsies were obtained from the right side of the maxilla and on Day 42 final biopsies were taken from the same healing sites. In addition, serum samples were obtained on Days 0, 14, 28 and 42. All samples were analyzed for Zn content using atomic absorption spectrophotometry. The [Zn] of healing tissues was significantly higher (P less than 0.0005) than normal tissues. This was also true when healing tissues were compared to normal tissues during the Zn supplementation phase (Day 28 vs. Day 42; P less than 0.005). Zn supplementation resulted in significant increases in Zn levels in normal (Day 0 vs. Day 28; P less than 0.05) and healing tissues (Day 14 vs. Day 42; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)