Nuclear and cytoplasmic bcl-2 expression in endometrial hyperplasia and adenocarcinoma

The bcl-2 proto-oncogene, which inhibits programmed cell death (apoptosis), has recently been found to be cyclically expressed in human endometrium. In order to investigate its role in endometrial hyperlasia and neoplasia, bcl-2 expression was studied in 25 cases of endometrial carcinoma and 20 cases of endometrial hyperplasia (eight simple, two complex, and ten atypical hyperplasias). Uniform intense cytoplasmic bcl-2 expression was found in all cases of non-atypical hyperplasia, and less strong positivity in eight out of ten cases of atypical hyperplasia. In well-differentiated carcinomas, nine out of ten showed weak to moderate bcl-2 expression, whereas six out of seven poorly differentiated carcinomas were bcl-2-negative. Moderately differentiated tumours were an intermediate group, with six out of eight being positive. Widespread localization of bcl-2 protein to the chromosomes of dividing cells was also demonstrated, regardless of cytoplasmic bcl-2 expression, with rare staining of interphase nuclei. Our findings suggest a role for bcl-2 in the natural history of endometrial neoplasia and studies are needed to determine its usefulness as a prognostic marker. The finding of bcl-2 localization to chromosomes has important implications for its mode and site of action.     

Differential expression of cdk inhibitors p16, p21cip1, p27kip1, and cyclin E in cervical cytological smears prepared by the ThinPrep method

Our objective was to correlate p16, p21cip1, p27kip1, and cyclin E protein expression with the degree of dysplasia on ThinPrep Papanicolaou (Pap) smears using a modified immunoperoxidase staining. Smears read as normal, atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), or high-grade SIL (HSIL) were identified and tested for high-risk human papillomavirus (HR-HPV). Additional smears were processed for immunoperoxidase for p16, p21cip1, p27kip1, and cyclin E. Thirty-four smears were satisfactory for study. The p16 was positive in all nine HSIL, in four of nine LSIL, and in one of seven ASC-US. The p27kip1 was positive in all nine HSIL, in eight of nine LSIL, and in one of seven ASC-US. The p21cip1 was positive in all nine HSIL, in one of nine LSIL, and in one of seven ASC-US. Cyclin E was positive in seven of nine HSIL and in one of nine LSIL and in none of the ASC-US smears. Normal smears were negative for all the antigens. There was poor correlation of protein expression and HR-HPV infection. We concluded that p16, p21cip1, p27kip1, and cyclin E can be demonstrated on Pap smears and they are expressed differentially in dysplastic cells, with highest expression in HSIL. The p21cip1 and cyclin E showed the greatest correlation with HSIL.     

Two novel mutations in the EPM2A gene in a Korean patient with Lafora's progressive myoclonus epilepsy

The progressive myoclonus epilepsy of the Lafora type (LD; MIM 254780) is a rare autosomal recessive disorder characterized by epilepsy, myoclonus, progressive neurological deterioration, and the presence of periodic acid-Schiff-positive polyglucosan inclusions (Lafora bodies). Mutations in the EPM2A gene have recently been found to cause LD and about 30 or more mutations have been reported thus far. LD is relatively common in countries of the Mediterranean Basin, the Middle East, India, and Pakistan. Although a few sporadic cases with the typical LD phenotype have also been reported in the Far East including Korea and Japan, a recent effort to find mutations in Japanese LD families was not successful. In the present study, we report two novel mutations in a Korean girl with LD; a 1-bp insertion mutation (c.223insC; G75fsX107) in exon 1 and a missense mutation (c.559A>G; T187A) in exon 3 of the EPM2A gene. To our knowledge, this is the first report of a genetically confirmed case of LD in Koreans and also in the Far East.     

Use of a multiplex PCR-based reverse line blot (mPCR/RLB) hybridisation assay for the rapid identification of bacterial pathogens.

The aim of this study was to develop a sensitive and reliable method for the molecular identification of pathogenic bacteria. A multiplex PCR-based reverse line blot (mPCR/RLB) hybridisation assay was developed and evaluated for the rapid identification of 24 systemic and respiratory bacterial pathogens in routine diagnosis. All species-specific probes designed for the RLB hybridised with amplified DNA only from the corresponding species. Sensitivity limits of the mPCR/RLB assay varied among the 24 target organisms from 0.05 pg to 0.5 ng of genomic DNA. The sensitivity of the assay was 2 x 10(2) CFU/mL for Streptococcus pneumoniae and 6 x 10(2) CFU/mL for Escherichia coli. The specificity of each probe was tested against 24 species. There were no cross-reactions among any of the 43 probes. The mPCR/RLB assay appeared to be a useful alternative tool for the molecular identification of common pathogens.     

Comparison of flow cytometry and retrospectively applied static cytometry on lymphoid tissue

Twenty cases of non-Hodgkin's malignant lymphoma were examined using both flow cytometry (FCM) and static cytometry (SCM) DNA analysis to detect aneuploidic cell populations. FCM was performed on fresh cell suspensions whilst SCM was performed retrospectively on formalin-fixed, paraffin-embedded samples of the same tissue. A total of 34 aneuploidic cell lines were detected by FCM compared to a total of 41 detected by SCM. Of the 20 cases 14 showed DNA indexes within 10% of each other for each method, indicating a reasonable degree of comparability between the two methods. Of the 6 cases which did not show comparable DNA indexes, 2 displayed similar cell lines for both methods, but the major abnormal cell populations were of different ploidy by SCM as compared to FCM. A qualitative comparison is thus possible between these two cases. The results suggest that retrospectively applied SCM ploidy analysis of lymphoid tissue is comparable to FCM on fresh tissue samples and can thus be used in retrospective studies of both prognostic and diagnostic significance.     

Mutagenic activity from nitrosation of oligoamines

To determine structural features necessary for the production of direct mutagenic activity from oligoamine-nitrate reaction mixtures, we systematically tested a group of aliphatic amine substrates for comutagenic action with nitrite. The ability to react with nitrite and form direct-acting mutagenic derivatives was common to a reasonably well defined class of aliphatic polyamines. In general, primary-secondary diamino compounds were mutagenic in the Ames Salmonella tester system when reacted with nitrite, whereas primary and secondary amines produced no direct mutagenic activity when tested separately. In combination with teritary amino groups, primary amines were inactive; one secondary-tertiary amine was tested, and this substrate produced mutagenic activity.